- Tracepoints should not give warning on OOM failures
- Use special field for function pointer in trace event
- Fix igrab issues in uprobes
- Fixes to the new histogram triggers
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Merge tag 'trace-v4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Various fixes in tracing:
- Tracepoints should not give warning on OOM failures
- Use special field for function pointer in trace event
- Fix igrab issues in uprobes
- Fixes to the new histogram triggers"
* tag 'trace-v4.17-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracepoint: Do not warn on ENOMEM
tracing: Add field modifier parsing hist error for hist triggers
tracing: Add field parsing hist error for hist triggers
tracing: Restore proper field flag printing when displaying triggers
tracing: initcall: Ordered comparison of function pointers
tracing: Remove igrab() iput() call from uprobes.c
tracing: Fix bad use of igrab in trace_uprobe.c
Currently, the bpf_current_task_under_cgroup helper has a check where if
the BPF program is running in_interrupt(), it will return -EINVAL. This
prevents the helper to be used in many useful scenarios, particularly
BPF programs attached to Perf Events.
This commit removes the check. Tested a few NMI (Perf Event) and some
softirq context, the helper returns the correct result.
Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull timer fixes from Thomas Gleixner:
"Two fixes from the timer departement:
- Fix a long standing issue in the NOHZ tick code which causes RB
tree corruption, delayed timers and other malfunctions. The cause
for this is code which modifies the expiry time of an enqueued
hrtimer.
- Revert the CLOCK_MONOTONIC/CLOCK_BOOTTIME unification due to
regression reports. Seems userspace _is_ relying on the documented
behaviour despite our hope that it wont"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME
tick/sched: Do not mess with an enqueued hrtimer
Currently, stackmap and bpf_get_stackid helper are provided
for bpf program to get the stack trace. This approach has
a limitation though. If two stack traces have the same hash,
only one will get stored in the stackmap table,
so some stack traces are missing from user perspective.
This patch implements a new helper, bpf_get_stack, will
send stack traces directly to bpf program. The bpf program
is able to see all stack traces, and then can do in-kernel
processing or send stack traces to user space through
shared map or bpf_perf_event_output.
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
If the user specifies an invalid field modifier for a hist trigger,
the current code correctly flags that as an error, but doesn't tell
the user what happened.
Fix this by invoking hist_err() with an appropriate message when
invalid modifiers are specified.
Before:
# echo 'hist:keys=pid:ts0=common_timestamp.junkusecs' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist
After:
# echo 'hist:keys=pid:ts0=common_timestamp.junkusecs' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist
ERROR: Invalid field modifier: junkusecs
Last command: keys=pid:ts0=common_timestamp.junkusecs
Link: http://lkml.kernel.org/r/b043c59fa79acd06a5f14a1d44dee9e5a3cd1248.1524790601.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If the user specifies a nonexistent field for a hist trigger, the
current code correctly flags that as an error, but doesn't tell the
user what happened.
Fix this by invoking hist_err() with an appropriate message when
nonexistent fields are specified.
Before:
# echo 'hist:keys=pid:ts0=common_timestamp.usecs' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist
After:
# echo 'hist:keys=pid:ts0=common_timestamp.usecs' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist
ERROR: Couldn't find field: pid
Last command: keys=pid:ts0=common_timestamp.usecs
Link: http://lkml.kernel.org/r/fdc8746969d16906120f162b99dd71c741e0b62c.1524790601.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The flag-printing code used when displaying hist triggers somehow got
dropped during refactoring of the inter-event patchset. This restores
it.
Below are a couple examples - in the first case, .usecs wasn't being
displayed properly for common_timestamps and the second illustrates
the same for other flags such as .execname.
Before:
# echo 'hist:key=common_pid.execname:val=count:sort=count' > /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
# cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
hist:keys=common_pid:vals=hitcount,count:sort=count:size=2048 [active]
# echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
# cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
hist:keys=pid:vals=hitcount:ts0=common_timestamp:sort=hitcount:size=2048:clock=global if comm=="cyclictest" [active]
After:
# echo 'hist:key=common_pid.execname:val=count:sort=count' > /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
# cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger
hist:keys=common_pid.execname:vals=hitcount,count:sort=count:size=2048 [active]
# echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
# cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
hist:keys=pid:vals=hitcount:ts0=common_timestamp.usecs:sort=hitcount:size=2048:clock=global if comm=="cyclictest" [active]
Link: http://lkml.kernel.org/r/492bab42ff21806600af98a8ea901af10efbee0c.1524790601.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Add workqueue forward declaration (for new work, but a nice clean up)
- seftest fixes for the new histogram code
- Print output fix for hwlat tracer
- Fix missing system call events - due to change in x86 syscall naming
- Fix kprobe address being used by perf being hashed
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Merge tag 'trace-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Add workqueue forward declaration (for new work, but a nice clean up)
- seftest fixes for the new histogram code
- Print output fix for hwlat tracer
- Fix missing system call events - due to change in x86 syscall naming
- Fix kprobe address being used by perf being hashed
* tag 'trace-v4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix missing tab for hwlat_detector print format
selftests: ftrace: Add a testcase for multiple actions on trigger
selftests: ftrace: Fix trigger extended error testcase
kprobes: Fix random address output of blacklist file
tracing: Fix kernel crash while using empty filter with perf
tracing/x86: Update syscall trace events to handle new prefixed syscall func names
tracing: Add missing forward declaration
As Miklos reported and suggested:
This pattern repeats two times in trace_uprobe.c and in
kernel/events/core.c as well:
ret = kern_path(filename, LOOKUP_FOLLOW, &path);
if (ret)
goto fail_address_parse;
inode = igrab(d_inode(path.dentry));
path_put(&path);
And it's wrong. You can only hold a reference to the inode if you
have an active ref to the superblock as well (which is normally
through path.mnt) or holding s_umount.
This way unmounting the containing filesystem while the tracepoint is
active will give you the "VFS: Busy inodes after unmount..." message
and a crash when the inode is finally put.
Solution: store path instead of inode.
This patch fixes two instances in trace_uprobe.c. struct path is added to
struct trace_uprobe to keep the inode and containing mount point
referenced.
Link: http://lkml.kernel.org/r/20180423172135.4050588-1-songliubraving@fb.com
Fixes: f3f096cfed ("tracing: Provide trace events interface for uprobes")
Fixes: 33ea4b2427 ("perf/core: Implement the 'perf_uprobe' PMU")
Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Howard McLauchlan <hmclauchlan@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Reported-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Revert commits
92af4dcb4e ("tracing: Unify the "boot" and "mono" tracing clocks")
127bfa5f43 ("hrtimer: Unify MONOTONIC and BOOTTIME clock behavior")
7250a4047a ("posix-timers: Unify MONOTONIC and BOOTTIME clock behavior")
d6c7270e91 ("timekeeping: Remove boot time specific code")
f2d6fdbfd2 ("Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior")
d6ed449afd ("timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock")
72199320d4 ("timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock")
As stated in the pull request for the unification of CLOCK_MONOTONIC and
CLOCK_BOOTTIME, it was clear that we might have to revert the change.
As reported by several folks systemd and other applications rely on the
documented behaviour of CLOCK_MONOTONIC on Linux and break with the above
changes. After resume daemons time out and other timeout related issues are
observed. Rafael compiled this list:
* systemd kills daemons on resume, after >WatchdogSec seconds
of suspending (Genki Sky). [Verified that that's because systemd uses
CLOCK_MONOTONIC and expects it to not include the suspend time.]
* systemd-journald misbehaves after resume:
systemd-journald[7266]: File /var/log/journal/016627c3c4784cd4812d4b7e96a34226/system.journal
corrupted or uncleanly shut down, renaming and replacing.
(Mike Galbraith).
* NetworkManager reports "networking disabled" and networking is broken
after resume 50% of the time (Pavel). [May be because of systemd.]
* MATE desktop dims the display and starts the screensaver right after
system resume (Pavel).
* Full system hang during resume (me). [May be due to systemd or NM or both.]
That happens on debian and open suse systems.
It's sad, that these problems were neither catched in -next nor by those
folks who expressed interest in this change.
Reported-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Reported-by: Genki Sky <sky@genki.is>,
Reported-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kevin Easton <kevin@guarana.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
It's been missing for a while but no one is touching that up. Fix it.
Link: http://lkml.kernel.org/r/20180315060639.9578-1-peterx@redhat.com
CC: Ingo Molnar <mingo@kernel.org>
Cc:stable@vger.kernel.org
Fixes: 7b2c862501 ("tracing: Add NMI tracing in hwlat detector")
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Kernel is crashing when user tries to record 'ftrace:function' event
with empty filter:
# perf record -e ftrace:function --filter="" ls
# dmesg
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
Oops: 0000 [#1] SMP PTI
...
RIP: 0010:ftrace_profile_set_filter+0x14b/0x2d0
RSP: 0018:ffffa4a7c0da7d20 EFLAGS: 00010246
RAX: ffffa4a7c0da7d64 RBX: 0000000000000000 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000000092 RDI: ffff8c48ffc968f0
...
Call Trace:
_perf_ioctl+0x54a/0x6b0
? rcu_all_qs+0x5/0x30
...
After patch:
# perf record -e ftrace:function --filter="" ls
failed to set filter "" on event ftrace:function with 22 (Invalid argument)
Also, if user tries to echo "" > filter, it used to throw an error.
This behavior got changed by commit 80765597bc ("tracing: Rewrite
filter logic to be simpler and faster"). This patch restores the
behavior as a side effect:
Before patch:
# echo "" > filter
#
After patch:
# echo "" > filter
bash: echo: write error: Invalid argument
#
Link: http://lkml.kernel.org/r/20180420150758.19787-1-ravi.bangoria@linux.ibm.com
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull networking fixes from David Miller:
1) Fix rtnl deadlock in ipvs, from Julian Anastasov.
2) s390 qeth fixes from Julian Wiedmann (control IO completion stalls,
bad MAC address update sequence, request side races on command IO
timeouts).
3) Handle seq_file overflow properly in l2tp, from Guillaume Nault.
4) Fix VLAN priority mappings in cpsw driver, from Ivan Khoronzhuk.
5) Packet scheduler ife action fixes (malformed TLV lengths, etc.) from
Alexander Aring.
6) Fix out of bounds access in tcp md5 option parser, from Jann Horn.
7) Missing netlink attribute policies in rtm_ipv6_policy table, from
Eric Dumazet.
8) Missing socket address length checks in l2tp and pppoe connect, from
Guillaume Nault.
9) Fix netconsole over team and bonding, from Xin Long.
10) Fix race with AF_PACKET socket state bitfields, from Willem de
Bruijn.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (51 commits)
ice: Fix insufficient memory issue in ice_aq_manage_mac_read
sfc: ARFS filter IDs
net: ethtool: Add missing kernel doc for FEC parameters
packet: fix bitfield update race
ice: Do not check INTEVENT bit for OICR interrupts
ice: Fix incorrect comment for action type
ice: Fix initialization for num_nodes_added
igb: Fix the transmission mode of queue 0 for Qav mode
ixgbevf: ensure xdp_ring resources are free'd on error exit
team: fix netconsole setup over team
amd-xgbe: Only use the SFP supported transceiver signals
amd-xgbe: Improve KR auto-negotiation and training
amd-xgbe: Add pre/post auto-negotiation phy hooks
pppoe: check sockaddr length in pppoe_connect()
l2tp: check sockaddr length in pppol2tp_connect()
net: phy: marvell: clear wol event before setting it
ipv6: add RTA_TABLE and RTA_PREFSRC to rtm_ipv6_policy
bonding: do not set slave_dev npinfo before slave_enable_netpoll in bond_enslave
tcp: don't read out-of-bounds opsize
ibmvnic: Clean actual number of RX or TX pools
...
Daniel Borkmann says:
====================
pull-request: bpf 2018-04-21
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix a deadlock between mm->mmap_sem and bpf_event_mutex when
one task is detaching a BPF prog via perf_event_detach_bpf_prog()
and another one dumping through bpf_prog_array_copy_info(). For
the latter we move the copy_to_user() out of the bpf_event_mutex
lock to fix it, from Yonghong.
2) Fix test_sock and test_sock_addr.sh failures. The former was
hitting rlimit issues and the latter required ping to specify
the address family, from Yonghong.
3) Remove a dead check in sockmap's sock_map_alloc(), from Jann.
4) Add generated files to BPF kselftests gitignore that were previously
missed, from Anders.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This warning message is not very helpful, as the return value should
already show information about the error. Also, this message will
spam dmesg if the user space does testing in a loop, like:
for x in {0..5}
do
echo p:xx xx+$x >> /sys/kernel/debug/tracing/kprobe_events
done
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Song Liu <songliubraving@fb.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20180413185513.3626052-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull more perf updates from Thomas Gleixner:
"A rather large set of perf updates:
Kernel:
- Fix various initialization issues
- Prevent creating [ku]probes for not CAP_SYS_ADMIN users
Tooling:
- Show only failing syscalls with 'perf trace --failure' (Arnaldo
Carvalho de Melo)
e.g: See what 'openat' syscalls are failing:
# perf trace --failure -e openat
762.323 ( 0.007 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video2) = -1 ENOENT No such file or directory
<SNIP N /dev/videoN open attempts... sigh, where is that improvised camera lid?!? >
790.228 ( 0.008 ms): VideoCapture/4566 openat(dfd: CWD, filename: /dev/video63) = -1 ENOENT No such file or directory
^C#
- Show information about the event (freq, nr_samples, total
period/nr_events) in the annotate --tui and --stdio2 'perf
annotate' output, similar to the first line in the 'perf report
--tui', but just for the samples for a the annotated symbol
(Arnaldo Carvalho de Melo)
- Introduce 'perf version --build-options' to show what features were
linked, aliased as well as a shorter 'perf -vv' (Jin Yao)
- Add a "dso_size" sort order (Kim Phillips)
- Remove redundant ')' in the tracepoint output in 'perf trace'
(Changbin Du)
- Synchronize x86's cpufeatures.h, no effect on toolss (Arnaldo
Carvalho de Melo)
- Show group details on the title line in the annotate browser and
'perf annotate --stdio2' output, so that the per-event columns can
have headers (Arnaldo Carvalho de Melo)
- Fixup vertical line separating metrics from instructions and
cleaning unused lines at the bottom, both in the annotate TUI
browser (Arnaldo Carvalho de Melo)
- Remove duplicated 'samples' in lost samples warning in
'perf report' (Arnaldo Carvalho de Melo)
- Synchronize i915_drm.h, silencing the perf build process,
automagically adding support for the new DRM_I915_QUERY ioctl
(Arnaldo Carvalho de Melo)
- Make auxtrace_queues__add_buffer() allocate struct buffer, from a
patchkit already applied (Adrian Hunter)
- Fix the --stdio2/TUI annotate output to include group details, be
it for a recorded '{a,b,f}' explicit event group or when forcing
group display using 'perf report --group' for a set of events not
recorded as a group (Arnaldo Carvalho de Melo)
- Fix display artifacts in the ui browser (base class for the
annotate and main report/top TUI browser) related to the extra
title lines work (Arnaldo Carvalho de Melo)
- perf auxtrace refactorings, leftovers from a previously partially
processed patchset (Adrian Hunter)
- Fix the builtin clang build (Sandipan Das, Arnaldo Carvalho de
Melo)
- Synchronize i915_drm.h, silencing a perf build warning and in the
process automagically adding support for a new ioctl command
(Arnaldo Carvalho de Melo)
- Fix a strncpy issue in uprobe tracing"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
perf/core: Need CAP_SYS_ADMIN to create k/uprobe with perf_event_open()
tracing/uprobe_event: Fix strncpy corner case
perf/core: Fix perf_uprobe_init()
perf/core: Fix perf_kprobe_init()
perf/core: Fix use-after-free in uprobe_perf_close()
perf tests clang: Fix function name for clang IR test
perf clang: Add support for recent clang versions
perf tools: Fix perf builds with clang support
perf tools: No need to include namespaces.h in util.h
perf hists browser: Remove leftover from row returned from refresh
perf hists browser: Show extra_title_lines in the 'D' debug hotkey
perf auxtrace: Make auxtrace_queues__add_buffer() do CPU filtering
tools headers uapi: Synchronize i915_drm.h
perf report: Remove duplicated 'samples' in lost samples warning
perf ui browser: Fixup cleaning unused lines at the bottom
perf annotate browser: Fixup vertical line separating metrics from instructions
perf annotate: Show group details on the title line
perf auxtrace: Make auxtrace_queues__add_buffer() allocate struct buffer
perf/x86/intel: Move regs->flags EXACT bit init
perf trace: Remove redundant ')'
...
- Replace open coded "ARRAY_SIZE()" with macro
- Updates to uprobes
- Bug fix for perf event filter on error path
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Merge tag 'trace-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"A few clean ups and bug fixes:
- replace open coded "ARRAY_SIZE()" with macro
- updates to uprobes
- bug fix for perf event filter on error path"
* tag 'trace-v4.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Enforce passing in filter=NULL to create_filter()
trace_uprobe: Simplify probes_seq_show()
trace_uprobe: Use %lx to display offset
tracing/uprobe: Add support for overlayfs
tracing: Use ARRAY_SIZE() macro instead of open coding it
There's some inconsistency with what to set the output parameter filterp
when passing to create_filter(..., struct event_filter **filterp).
Whatever filterp points to, should be NULL when calling this function. The
create_filter() calls create_filter_start() with a pointer to a local
"filter" variable that is set to NULL. The create_filter_start() has a
WARN_ON() if the passed in pointer isn't pointing to a value set to NULL.
Ideally, create_filter() should pass the filterp variable it received to
create_filter_start() and not hide it as with a local variable, this allowed
create_filter() to fail, and not update the passed in filter, and the caller
of create_filter() then tried to free filter, which was never initialized to
anything, causing memory corruption.
Link: http://lkml.kernel.org/r/00000000000032a0c30569916870@google.com
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Reported-by: syzbot+dadcc936587643d7f568@syzkaller.appspotmail.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Simplify probes_seq_show() function. No change in output
before and after patch.
Link: http://lkml.kernel.org/r/20180315082756.9050-2-ravi.bangoria@linux.vnet.ibm.com
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tu->offset is unsigned long, not a pointer, thus %lx should
be used to print it, not the %px.
Link: http://lkml.kernel.org/r/20180315082756.9050-1-ravi.bangoria@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 0e4d819d08 ("trace_uprobe: Display correct offset in uprobe_events")
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
uprobes cannot successfully attach to binaries located in a directory
mounted with overlayfs.
To verify, create directories for mounting overlayfs
(upper,lower,work,merge), move some binary into merge/ and use readelf
to obtain some known instruction of the binary. I used /bin/true and the
entry instruction(0x13b0):
$ mount -t overlay overlay -o lowerdir=lower,upperdir=upper,workdir=work merge
$ cd /sys/kernel/debug/tracing
$ echo 'p:true_entry PATH_TO_MERGE/merge/true:0x13b0' > uprobe_events
$ echo 1 > events/uprobes/true_entry/enable
This returns 'bash: echo: write error: Input/output error' and dmesg
tells us 'event trace: Could not enable event true_entry'
This change makes create_trace_uprobe() look for the real inode of a
dentry. In the case of normal filesystems, this simplifies to just
returning the inode. In the case of overlayfs(and similar fs) we will
obtain the underlying dentry and corresponding inode, upon which uprobes
can successfully register.
Running the example above with the patch applied, we can see that the
uprobe is enabled and will output to trace as expected.
Link: http://lkml.kernel.org/r/20180410231030.2720-1-hmclauchlan@fb.com
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
It is useless to re-invent the ARRAY_SIZE macro so let's use it instead
of DATA_CNT.
Found with Coccinelle with the following semantic patch:
@r depends on (org || report)@
type T;
T[] E;
position p;
@@
(
(sizeof(E)@p /sizeof(*E))
|
(sizeof(E)@p /sizeof(E[...]))
|
(sizeof(E)@p /sizeof(T))
)
Link: http://lkml.kernel.org/r/20171016012250.26453-1-jeremy.lefaure@lse.epita.fr
Signed-off-by: Jérémy Lefaure <jeremy.lefaure@lse.epita.fr>
[ Removed useless include of kernel.h ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
syzbot reported a possible deadlock in perf_event_detach_bpf_prog.
The error details:
======================================================
WARNING: possible circular locking dependency detected
4.16.0-rc7+ #3 Not tainted
------------------------------------------------------
syz-executor7/24531 is trying to acquire lock:
(bpf_event_mutex){+.+.}, at: [<000000008a849b07>] perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854
but task is already holding lock:
(&mm->mmap_sem){++++}, at: [<0000000038768f87>] vm_mmap_pgoff+0x198/0x280 mm/util.c:353
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (&mm->mmap_sem){++++}:
__might_fault+0x13a/0x1d0 mm/memory.c:4571
_copy_to_user+0x2c/0xc0 lib/usercopy.c:25
copy_to_user include/linux/uaccess.h:155 [inline]
bpf_prog_array_copy_info+0xf2/0x1c0 kernel/bpf/core.c:1694
perf_event_query_prog_array+0x1c7/0x2c0 kernel/trace/bpf_trace.c:891
_perf_ioctl kernel/events/core.c:4750 [inline]
perf_ioctl+0x3e1/0x1480 kernel/events/core.c:4770
vfs_ioctl fs/ioctl.c:46 [inline]
do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
SYSC_ioctl fs/ioctl.c:701 [inline]
SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x42/0xb7
-> #0 (bpf_event_mutex){+.+.}:
lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920
__mutex_lock_common kernel/locking/mutex.c:756 [inline]
__mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
perf_event_detach_bpf_prog+0x92/0x3d0 kernel/trace/bpf_trace.c:854
perf_event_free_bpf_prog kernel/events/core.c:8147 [inline]
_free_event+0xbdb/0x10f0 kernel/events/core.c:4116
put_event+0x24/0x30 kernel/events/core.c:4204
perf_mmap_close+0x60d/0x1010 kernel/events/core.c:5172
remove_vma+0xb4/0x1b0 mm/mmap.c:172
remove_vma_list mm/mmap.c:2490 [inline]
do_munmap+0x82a/0xdf0 mm/mmap.c:2731
mmap_region+0x59e/0x15a0 mm/mmap.c:1646
do_mmap+0x6c0/0xe00 mm/mmap.c:1483
do_mmap_pgoff include/linux/mm.h:2223 [inline]
vm_mmap_pgoff+0x1de/0x280 mm/util.c:355
SYSC_mmap_pgoff mm/mmap.c:1533 [inline]
SyS_mmap_pgoff+0x462/0x5f0 mm/mmap.c:1491
SYSC_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:91
do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x42/0xb7
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(&mm->mmap_sem);
lock(bpf_event_mutex);
lock(&mm->mmap_sem);
lock(bpf_event_mutex);
*** DEADLOCK ***
======================================================
The bug is introduced by Commit f371b304f1 ("bpf/tracing: allow
user space to query prog array on the same tp") where copy_to_user,
which requires mm->mmap_sem, is called inside bpf_event_mutex lock.
At the same time, during perf_event file descriptor close,
mm->mmap_sem is held first and then subsequent
perf_event_detach_bpf_prog needs bpf_event_mutex lock.
Such a senario caused a deadlock.
As suggested by Daniel, moving copy_to_user out of the
bpf_event_mutex lock should fix the problem.
Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Reported-by: syzbot+dc5ca0e4c9bfafaf2bae@syzkaller.appspotmail.com
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
- Tom Zanussi's extended histogram work
This adds the synthetic events to have histograms from multiple event data
Adds triggers "onmatch" and "onmax" to call the synthetic events
Several updates to the histogram code from this
- Allow way to nest ring buffer calls in the same context
- Allow absolute time stamps in ring buffer
- Rewrite of filter code parsing based on Al Viro's suggestions
- Setting of trace_clock to global if TSC is unstable (on boot)
- Better OOM handling when allocating large ring buffers
- Added initcall tracepoints (consolidated initcall_debug code with them)
And other various fixes and clean ups
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Merge tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"New features:
- Tom Zanussi's extended histogram work.
This adds the synthetic events to have histograms from multiple
event data Adds triggers "onmatch" and "onmax" to call the
synthetic events Several updates to the histogram code from this
- Allow way to nest ring buffer calls in the same context
- Allow absolute time stamps in ring buffer
- Rewrite of filter code parsing based on Al Viro's suggestions
- Setting of trace_clock to global if TSC is unstable (on boot)
- Better OOM handling when allocating large ring buffers
- Added initcall tracepoints (consolidated initcall_debug code with
them)
And other various fixes and clean ups"
* tag 'trace-v4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (68 commits)
init: Have initcall_debug still work without CONFIG_TRACEPOINTS
init, tracing: Have printk come through the trace events for initcall_debug
init, tracing: instrument security and console initcall trace events
init, tracing: Add initcall trace events
tracing: Add rcu dereference annotation for test func that touches filter->prog
tracing: Add rcu dereference annotation for filter->prog
tracing: Fixup logic inversion on setting trace_global_clock defaults
tracing: Hide global trace clock from lockdep
ring-buffer: Add set/clear_current_oom_origin() during allocations
ring-buffer: Check if memory is available before allocation
lockdep: Add print_irqtrace_events() to __warn
vsprintf: Do not preprocess non-dereferenced pointers for bprintf (%px and %pK)
tracing: Uninitialized variable in create_tracing_map_fields()
tracing: Make sure variable string fields are NULL-terminated
tracing: Add action comparisons when testing matching hist triggers
tracing: Don't add flag strings when displaying variable references
tracing: Fix display of hist trigger expressions containing timestamps
ftrace: Drop a VLA in module_exists()
tracing: Mention trace_clock=global when warning about unstable clocks
tracing: Default to using trace_global_clock if sched_clock is unstable
...
Fix string fetch function to terminate with NUL.
It is OK to drop the rest of string.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: security@kernel.org
Cc: 范龙飞 <long7573@126.com>
Fixes: 5baaa59ef0 ("tracing/probes: Implement 'memory' fetch method for uprobes")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Similarly to the uprobe PMU fix in perf_kprobe_init(), fix error
handling in perf_uprobe_init() as well.
Reported-by: 范龙飞 <long7573@126.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: e12f03d703 ("perf/core: Implement the 'perf_kprobe' PMU")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A boot up test function update_pred_fn() dereferences filter->prog without
the proper rcu annotation.
To do this, we must also take the event_mutex first. Normally, this isn't
needed because this test function can not race with other use cases that
touch the event filters (it is disabled if any events are enabled).
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
ftrace_function_set_filter() referenences filter->prog without annotation
and sparse complains about it. It needs a rcu_dereference_protected()
wrapper.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In commit 932066a15335 ("tracing: Default to using trace_global_clock if
sched_clock is unstable"), the logic for deciding to override the
default clock if unstable was reversed from the earlier posting. I was
trying to reduce the width of the message by using an early return
rather than a if-block, but reverted back to using the if-block and
accidentally left the predicate inverted.
Link: http://lkml.kernel.org/r/20180404212450.26646-1-chris@chris-wilson.co.uk
Fixes: 932066a15335 ("tracing: Default to using trace_global_clock if sched_clock is unstable")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Function tracing can trace in NMIs and such. If the TSC is determined
to be unstable, the tracing clock will switch to the global clock on
boot up, unless "trace_clock" is specified on the kernel command line.
The global clock disables interrupts to access sched_clock_cpu(), and in
doing so can be done within lockdep internals (because of function
tracing and NMIs). This can trigger false lockdep splats.
The trace_clock_global() is special, best not to trace the irq logic
within it.
Link: http://lkml.kernel.org/r/20180404145015.77bde42d@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As si_mem_available() can say there is enough memory even though the memory
available is not useable by the ring buffer, it is best to not kill innocent
applications because the ring buffer is taking up all the memory while it is
trying to allocate a great deal of memory.
If the allocator is user space (because kernel threads can also increase the
size of the kernel ring buffer on boot up), then after si_mem_available()
says there is enough memory, set the OOM killer to kill the current task if
an OOM triggers during the allocation.
Link: http://lkml.kernel.org/r/20180404062340.GD6312@dhcp22.suse.cz
Suggested-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The ring buffer is made up of a link list of pages. When making the ring
buffer bigger, it will allocate all the pages it needs before adding to the
ring buffer, and if it fails, it frees them and returns an error. This makes
increasing the ring buffer size an all or nothing action. When this was
first created, the pages were allocated with "NORETRY". This was to not
cause any Out-Of-Memory (OOM) actions from allocating the ring buffer. But
NORETRY was too strict, as the ring buffer would fail to expand even when
there's memory available, but was taken up in the page cache.
Commit 848618857d ("tracing/ring_buffer: Try harder to allocate") changed
the allocating from NORETRY to RETRY_MAYFAIL. The RETRY_MAYFAIL would
allocate from the page cache, but if there was no memory available, it would
simple fail the allocation and not trigger an OOM.
This worked fine, but had one problem. As the ring buffer would allocate one
page at a time, it could take up all memory in the system before it failed
to allocate and free that memory. If the allocation is happening and the
ring buffer allocates all memory and then tries to take more than available,
its allocation will not trigger an OOM, but if there's any allocation that
happens someplace else, that could trigger an OOM, even though once the ring
buffer's allocation fails, it would free up all the previous memory it tried
to allocate, and allow other memory allocations to succeed.
Commit d02bd27bd3 ("mm/page_alloc.c: calculate 'available' memory in a
separate function") separated out si_mem_availble() as a separate function
that could be used to see how much memory is available in the system. Using
this function to make sure that the ring buffer could be allocated before it
tries to allocate pages we can avoid allocating all memory in the system and
making it vulnerable to OOMs if other allocations are taking place.
Link: http://lkml.kernel.org/r/1522320104-6573-1-git-send-email-zhaoyang.huang@spreadtrum.com
CC: stable@vger.kernel.org
Cc: linux-mm@kvack.org
Fixes: 848618857d ("tracing/ring_buffer: Try harder to allocate")
Requires: d02bd27bd3 ("mm/page_alloc.c: calculate 'available' memory in a separate function")
Reported-by: Zhaoyang Huang <huangzhaoyang@gmail.com>
Tested-by: Joel Fernandes <joelaf@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Smatch complains that idx can be used uninitialized when we check if
(idx < 0). It has to be the first iteration through the loop and the
HIST_FIELD_FL_STACKTRACE bit has to be clear and the HIST_FIELD_FL_VAR
bit has to be set to reach the bug.
Link: http://lkml.kernel.org/r/20180328114815.GC29050@mwanda
Fixes: 30350d65ac ("tracing: Add variable support to hist triggers")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The strncpy() currently being used for variable string fields can
result in a lack of termination if the string length is equal to the
field size. Use the safer strscpy() instead, which will guarantee
termination.
Link: http://lkml.kernel.org/r/fb97c1e518fb358c12a4057d7445ba2c46956cd7.1522256721.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Actions also need to be considered when checking for matching triggers
- triggers differing only by action should be allowed, but currently
aren't because the matching check ignores the action and erroneously
returns -EEXIST.
Add and call an actions_match() function to address that.
Here's an example using onmatch() actions. The first -EEXIST shouldn't
occur because the onmatch() is different in the second wakeup_latency()
param. The second -EEXIST shouldn't occur because it's a different
action (in this case, it doesn't have an action, so shouldn't be seen
as being the same and therefore rejected).
In the after case, both are correctly accepted (and trying to add one of
them again returns -EEXIST as it should).
before:
# echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events
# echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
# echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
# echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
# echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: File exists
# echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
-su: echo: write error: File exists
after:
# echo 'wakeup_latency u64 lat; pid_t pid' >> /sys/kernel/debug/tracing/synthetic_events
# echo 'hist:keys=pid:ts0=common_timestamp.usecs if comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
# echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
# echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,next_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
# echo 'hist:keys=next_pid:onmatch(sched.sched_wakeup).wakeup_latency(sched.sched_switch.$wakeup_lat,prev_pid) if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
# echo 'hist:keys=next_pid if next_comm=="cyclictest"' >> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
Link: http://lkml.kernel.org/r/a7fd668b87ec10736c8f016ac4279c8480d50c2b.1522256721.git.tom.zanussi@linux.intel.com
Tested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Variable references should never have flags appended when displayed -
prevent that from happening.
Before:
# cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:...
After:
hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0:...
Link: http://lkml.kernel.org/r/913318a5610ef6b24af2522575f671fa6ee19b6b.1522256721.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When displaying hist triggers, variable references that have the
timestamp field flag set are erroneously displayed as common_timestamp
rather than the variable reference. Additionally, timestamp
expressions are displayed in the same way. Fix this by forcing the
timestamp flag handling to follow variable reference and expression
handling.
Before:
# cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs:...
After:
# cat /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
hist:keys=next_pid:vals=hitcount:wakeup_lat=common_timestamp.usecs-$ts0.usecs:...
Link: http://lkml.kernel.org/r/92746b06be67499c2a6217bd55395b350ad18fad.1522256721.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Mention the alternative of adding trace_clock=global to the kernel
command line when we detect that we've used an unstable clock across a
suspend/resume cycle.
Link: http://lkml.kernel.org/r/20180330150132.16903-2-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Across suspend, we may see a very large drift in timestamps if the sched
clock is unstable, prompting the global trace's ringbuffer code to warn
and suggest switching to the global clock. Preempt this request by
detecting when the sched clock is unstable (determined during
late_initcall) and automatically switching the default clock over to
trace_global_clock.
This should prevent requiring user interaction to resolve warnings such
as:
Delta way too big! 18446743856563626466 ts=18446744054496180323 write stamp = 197932553857
If you just came from a suspend/resume,
please switch to the trace global clock:
echo global > /sys/kernel/debug/tracing/trace_clock
Link: http://lkml.kernel.org/r/20180330150132.16903-1-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull trivial tree updates from Jiri Kosina.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial:
kfifo: fix inaccurate comment
tools/thermal: tmon: fix for segfault
net: Spelling s/stucture/structure/
edd: don't spam log if no EDD information is present
Documentation: Fix early-microcode.txt references after file rename
tracing: Block comments should align the * on each line
treewide: Fix typos in printk
GenWQE: Fix a typo in two comments
treewide: Align function definition open/close braces
Pull time(r) updates from Thomas Gleixner:
"A small set of updates for timers and timekeeping:
- The most interesting change is the consolidation of clock MONOTONIC
and clock BOOTTIME.
Clock MONOTONIC behaves now exactly like clock BOOTTIME and does
not longer ignore the time spent in suspend. A new clock
MONOTONIC_ACTIVE is provived which behaves like clock MONOTONIC in
kernels before this change. This allows applications to
programmatically check for the clock MONOTONIC behaviour.
As discussed in the review thread, this has the potential of
breaking user space and we might have to revert this. Knock on wood
that we can avoid that exercise.
- Updates to the NTP mechanism to improve accuracy
- A new kernel internal data structure to aid the ongoing Y2038 work.
- Cleanups and simplifications of the clocksource code.
- Make the alarmtimer code play nicely with debugobjects"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
alarmtimer: Init nanosleep alarm timer on stack
y2038: Introduce struct __kernel_old_timeval
tracing: Unify the "boot" and "mono" tracing clocks
hrtimer: Unify MONOTONIC and BOOTTIME clock behavior
posix-timers: Unify MONOTONIC and BOOTTIME clock behavior
timekeeping: Remove boot time specific code
Input: Evdev - unify MONOTONIC and BOOTTIME clock behavior
timekeeping: Make the MONOTONIC clock behave like the BOOTTIME clock
timekeeping: Add the new CLOCK_MONOTONIC_ACTIVE clock
timekeeping/ntp: Determine the multiplier directly from NTP tick length
timekeeping/ntp: Don't align NTP frequency adjustments to ticks
clocksource: Use ATTRIBUTE_GROUPS
clocksource: Use DEVICE_ATTR_RW/RO/WO to define device attributes
clocksource: Don't walk the clocksource list for empty override
Pull networking updates from David Miller:
1) Support offloading wireless authentication to userspace via
NL80211_CMD_EXTERNAL_AUTH, from Srinivas Dasari.
2) A lot of work on network namespace setup/teardown from Kirill Tkhai.
Setup and cleanup of namespaces now all run asynchronously and thus
performance is significantly increased.
3) Add rx/tx timestamping support to mv88e6xxx driver, from Brandon
Streiff.
4) Support zerocopy on RDS sockets, from Sowmini Varadhan.
5) Use denser instruction encoding in x86 eBPF JIT, from Daniel
Borkmann.
6) Support hw offload of vlan filtering in mvpp2 dreiver, from Maxime
Chevallier.
7) Support grafting of child qdiscs in mlxsw driver, from Nogah
Frankel.
8) Add packet forwarding tests to selftests, from Ido Schimmel.
9) Deal with sub-optimal GSO packets better in BBR congestion control,
from Eric Dumazet.
10) Support 5-tuple hashing in ipv6 multipath routing, from David Ahern.
11) Add path MTU tests to selftests, from Stefano Brivio.
12) Various bits of IPSEC offloading support for mlx5, from Aviad
Yehezkel, Yossi Kuperman, and Saeed Mahameed.
13) Support RSS spreading on ntuple filters in SFC driver, from Edward
Cree.
14) Lots of sockmap work from John Fastabend. Applications can use eBPF
to filter sendmsg and sendpage operations.
15) In-kernel receive TLS support, from Dave Watson.
16) Add XDP support to ixgbevf, this is significant because it should
allow optimized XDP usage in various cloud environments. From Tony
Nguyen.
17) Add new Intel E800 series "ice" ethernet driver, from Anirudh
Venkataramanan et al.
18) IP fragmentation match offload support in nfp driver, from Pieter
Jansen van Vuuren.
19) Support XDP redirect in i40e driver, from Björn Töpel.
20) Add BPF_RAW_TRACEPOINT program type for accessing the arguments of
tracepoints in their raw form, from Alexei Starovoitov.
21) Lots of striding RQ improvements to mlx5 driver with many
performance improvements, from Tariq Toukan.
22) Use rhashtable for inet frag reassembly, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1678 commits)
net: mvneta: improve suspend/resume
net: mvneta: split rxq/txq init and txq deinit into SW and HW parts
ipv6: frags: fix /proc/sys/net/ipv6/ip6frag_low_thresh
net: bgmac: Fix endian access in bgmac_dma_tx_ring_free()
net: bgmac: Correctly annotate register space
route: check sysctl_fib_multipath_use_neigh earlier than hash
fix typo in command value in drivers/net/phy/mdio-bitbang.
sky2: Increase D3 delay to sky2 stops working after suspend
net/mlx5e: Set EQE based as default TX interrupt moderation mode
ibmvnic: Disable irqs before exiting reset from closed state
net: sched: do not emit messages while holding spinlock
vlan: also check phy_driver ts_info for vlan's real device
Bluetooth: Mark expected switch fall-throughs
Bluetooth: Set HCI_QUIRK_SIMULTANEOUS_DISCOVERY for BTUSB_QCA_ROME
Bluetooth: btrsi: remove unused including <linux/version.h>
Bluetooth: hci_bcm: Remove DMI quirk for the MINIX Z83-4
sh_eth: kill useless check in __sh_eth_get_regs()
sh_eth: add sh_eth_cpu_data::no_xdfar flag
ipv6: factorize sk_wmem_alloc updates done by __ip6_append_data()
ipv4: factorize sk_wmem_alloc updates done by __ip_append_data()
...
Minor conflicts in drivers/net/ethernet/mellanox/mlx5/core/en_rep.c,
we had some overlapping changes:
1) In 'net' MLX5E_PARAMS_LOG_{SQ,RQ}_SIZE -->
MLX5E_REP_PARAMS_LOG_{SQ,RQ}_SIZE
2) In 'net-next' params->log_rq_size is renamed to be
params->log_rq_mtu_frames.
3) In 'net-next' params->hard_mtu is added.
Signed-off-by: David S. Miller <davem@davemloft.net>
== The problem ==
There are use-cases when a program of some type can be attached to
multiple attach points and those attach points must have different
permissions to access context or to call helpers.
E.g. context structure may have fields for both IPv4 and IPv6 but it
doesn't make sense to read from / write to IPv6 field when attach point
is somewhere in IPv4 stack.
Same applies to BPF-helpers: it may make sense to call some helper from
some attach point, but not from other for same prog type.
== The solution ==
Introduce `expected_attach_type` field in in `struct bpf_attr` for
`BPF_PROG_LOAD` command. If scenario described in "The problem" section
is the case for some prog type, the field will be checked twice:
1) At load time prog type is checked to see if attach type for it must
be known to validate program permissions correctly. Prog will be
rejected with EINVAL if it's the case and `expected_attach_type` is
not specified or has invalid value.
2) At attach time `attach_type` is compared with `expected_attach_type`,
if prog type requires to have one, and, if they differ, attach will
be rejected with EINVAL.
The `expected_attach_type` is now available as part of `struct bpf_prog`
in both `bpf_verifier_ops->is_valid_access()` and
`bpf_verifier_ops->get_func_proto()` () and can be used to check context
accesses and calls to helpers correspondingly.
Initially the idea was discussed by Alexei Starovoitov <ast@fb.com> and
Daniel Borkmann <daniel@iogearbox.net> here:
https://marc.info/?l=linux-netdev&m=152107378717201&w=2
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Introduce BPF_PROG_TYPE_RAW_TRACEPOINT bpf program type to access
kernel internal arguments of the tracepoints in their raw form.
>From bpf program point of view the access to the arguments look like:
struct bpf_raw_tracepoint_args {
__u64 args[0];
};
int bpf_prog(struct bpf_raw_tracepoint_args *ctx)
{
// program can read args[N] where N depends on tracepoint
// and statically verified at program load+attach time
}
kprobe+bpf infrastructure allows programs access function arguments.
This feature allows programs access raw tracepoint arguments.
Similar to proposed 'dynamic ftrace events' there are no abi guarantees
to what the tracepoints arguments are and what their meaning is.
The program needs to type cast args properly and use bpf_probe_read()
helper to access struct fields when argument is a pointer.
For every tracepoint __bpf_trace_##call function is prepared.
In assembler it looks like:
(gdb) disassemble __bpf_trace_xdp_exception
Dump of assembler code for function __bpf_trace_xdp_exception:
0xffffffff81132080 <+0>: mov %ecx,%ecx
0xffffffff81132082 <+2>: jmpq 0xffffffff811231f0 <bpf_trace_run3>
where
TRACE_EVENT(xdp_exception,
TP_PROTO(const struct net_device *dev,
const struct bpf_prog *xdp, u32 act),
The above assembler snippet is casting 32-bit 'act' field into 'u64'
to pass into bpf_trace_run3(), while 'dev' and 'xdp' args are passed as-is.
All of ~500 of __bpf_trace_*() functions are only 5-10 byte long
and in total this approach adds 7k bytes to .text.
This approach gives the lowest possible overhead
while calling trace_xdp_exception() from kernel C code and
transitioning into bpf land.
Since tracepoint+bpf are used at speeds of 1M+ events per second
this is valuable optimization.
The new BPF_RAW_TRACEPOINT_OPEN sys_bpf command is introduced
that returns anon_inode FD of 'bpf-raw-tracepoint' object.
The user space looks like:
// load bpf prog with BPF_PROG_TYPE_RAW_TRACEPOINT type
prog_fd = bpf_prog_load(...);
// receive anon_inode fd for given bpf_raw_tracepoint with prog attached
raw_tp_fd = bpf_raw_tracepoint_open("xdp_exception", prog_fd);
Ctrl-C of tracing daemon or cmdline tool that uses this feature
will automatically detach bpf program, unload it and
unregister tracepoint probe.
On the kernel side the __bpf_raw_tp_map section of pointers to
tracepoint definition and to __bpf_trace_*() probe function is used
to find a tracepoint with "xdp_exception" name and
corresponding __bpf_trace_xdp_exception() probe function
which are passed to tracepoint_probe_register() to connect probe
with tracepoint.
Addition of bpf_raw_tracepoint doesn't interfere with ftrace and perf
tracepoint mechanisms. perf_event_open() can be used in parallel
on the same tracepoint.
Multiple bpf_raw_tracepoint_open("xdp_exception", prog_fd) are permitted.
Each with its own bpf program. The kernel will execute
all tracepoint probes and all attached bpf programs.
In the future bpf_raw_tracepoints can be extended with
query/introspection logic.
__bpf_raw_tp_map section logic was contributed by Steven Rostedt
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Some functions definitions have either the initial open brace and/or
the closing brace outside of column 1.
Move those braces to column 1.
This allows various function analyzers like gnu complexity to work
properly for these modified functions.
Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Nicolin Chen <nicoleotsuka@gmail.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
take both a + and - sign to get to befor and after the symbol address.
But in actuality, the code does not support the minus. This fixes
that issue, and adds a few more selftests to kprobe events.
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Merge tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull kprobe fixes from Steven Rostedt:
"The documentation for kprobe events says that symbol offets can take
both a + and - sign to get to befor and after the symbol address.
But in actuality, the code does not support the minus. This fixes that
issue, and adds a few more selftests to kprobe events"
* tag 'trace-v4.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests: ftrace: Add a testcase for probepoint
selftests: ftrace: Add a testcase for string type with kprobe_event
selftests: ftrace: Add probe event argument syntax testcase
tracing: probeevent: Fix to support minus offset from symbol
In Documentation/trace/kprobetrace.txt, it says
@SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)
However, the parser doesn't parse minus offset correctly, since
commit 2fba0c8867 ("tracing/kprobes: Fix probe offset to be
unsigned") drops minus ("-") offset support for kprobe probe
address usage.
This fixes the traceprobe_split_symbol_offset() to parse minus
offset again with checking the offset range, and add a minus
offset check in kprobe probe address usage.
Link: http://lkml.kernel.org/r/152129028983.31874.13419301530285775521.stgit@devbox
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <tom.zanussi@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Fixes: 2fba0c8867 ("tracing/kprobes: Fix probe offset to be unsigned")
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fun set of conflict resolutions here...
For the mac80211 stuff, these were fortunately just parallel
adds. Trivially resolved.
In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.
In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.
The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.
The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:
====================
Due to bug fixes found by the syzkaller bot and taken into the for-rc
branch after development for the 4.17 merge window had already started
being taken into the for-next branch, there were fairly non-trivial
merge issues that would need to be resolved between the for-rc branch
and the for-next branch. This merge resolves those conflicts and
provides a unified base upon which ongoing development for 4.17 can
be based.
Conflicts:
drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
(IB/mlx5: Fix cleanup order on unload) added to for-rc and
commit b5ca15ad7e (IB/mlx5: Add proper representors support)
add as part of the devel cycle both needed to modify the
init/de-init functions used by mlx5. To support the new
representors, the new functions added by the cleanup patch
needed to be made non-static, and the init/de-init list
added by the representors patch needed to be modified to
match the init/de-init list changes made by the cleanup
patch.
Updates:
drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
prototypes added by representors patch to reflect new function
names as changed by cleanup patch
drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
stage list to match new order from cleanup patch
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We forgot to set the error code on this path so we return ERR_PTR(0)
which is NULL. It results in a NULL dereference in the caller.
Link: http://lkml.kernel.org/r/20180323113735.GC28518@mwanda
Fixes: 100719dcef ("tracing: Add simple expression support to hist triggers")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit 4bebdc7a85 ("bpf: add helper bpf_perf_prog_read_value")
added helper bpf_perf_prog_read_value so that perf_event type program
can read event counter and enabled/running time.
This commit, however, introduced a bug which allows this helper
for tracepoint type programs. This is incorrect as bpf_perf_prog_read_value
needs to access perf_event through its bpf_perf_event_data_kern type context,
which is not available for tracepoint type program.
This patch fixed the issue by separating bpf_func_proto between tracepoint
and perf_event type programs and removed bpf_perf_prog_read_value
from tracepoint func prototype.
Fixes: 4bebdc7a85 ("bpf: add helper bpf_perf_prog_read_value")
Reported-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Al Viro reviewed the filter logic of ftrace trace events and found it to be
very troubling. It creates a binary tree based on the logic operators and
walks it during tracing. He sent myself and Tom Zanussi a long explanation
(and formal proof) of how to do the string parsing better and end up with a
program array that can be simply iterated to come up with the correct
results.
I took his ideas and his pseudo code and rewrote the filter logic based on
them. In doing so, I was able to remove a lot of code, and have a much more
condensed filter logic in the process. I wrote a very long comment
describing the methadology that Al proposed in my own words. For more info
on how this works, read the comment above predicate_parse().
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The pred_funcs_##type arrays consist of five functions that are assigned
based on the ops. The array must be in the same order of the ops each
function represents. The PRED_FUNC_START macro denotes the op enum that
starts the op that maps to the pred_funcs_##type arrays. This is all very
subtle and prone to bugs if the code is changed.
Add comments describing how PRED_FUNC_START and pred_funcs_##type array is
used, and also a PRED_FUNC_MAX that is the maximum number of functions in
the arrays.
Clean up select_comparison_fn() that assigns the predicates to the
pred_funcs_##type array function as well as add protection in case an op is
passed in that does not map correctly to the array.
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Instead of having a separate enum that is the index into another array, like
a string array, make a single macro that combines them into a single list,
and then the two can not get out of sync. This makes it easier to add and
remove items.
The macro trick is:
#define DOGS \
C( JACK, "Jack Russell") \
C( ITALIAN, "Italian Greyhound") \
C( GERMAN, "German Shepherd")
#undef C
#define C(a, b) a
enum { DOGS };
#undef C
#define C(a, b) b
static char dogs[] = { DOGS };
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Unify the "boot" and "mono" tracing clocks and document the new behaviour.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kevin Easton <kevin@guarana.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20180301165150.489635255@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The replace_filter_string() frees the current string and then copies a given
string. But in the two locations that it was used, the allocation happened
right after the filter was allocated (nothing to replace). There's no need
for this to be a helper function. Embedding the allocation in the two places
where it was called will make changing the code in the future easier.
Also make the variable consistent (always use "filter_string" as the name,
as it was used in one instance as "filter_str")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
replace_system_preds() creates a filter list to free even when it doesn't
really need to have it. Only save filters that require synchronize_sched()
in the filter list to free. This will allow the code to be updated a bit
easier in the future.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The __alloc_filter() function does nothing more that allocate the filter.
There's no reason to have it as a helper function.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The filter code does open code string appending to produce an error message.
Instead it can be simplified by using trace_seq function helpers.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
There's no reason to BUG if there's a bug in the filtering code. Simply do a
warning and return.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Synthetic events can be done within the recording of other events. Notify
the ring buffer via ring_buffer_nest_start() and ring_buffer_nest_end() that
this is intended and not to block it due to its recursion protection.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The ring-buffer code has recusion protection in case tracing ends up tracing
itself, the ring-buffer will detect that it was called at the same context
(normal, softirq, interrupt or NMI), and not continue to record the event.
With the histogram synthetic events, they are called while tracing another
event at the same context. The recusion protection triggers because it
detects tracing at the same context and stops it.
Add ring_buffer_nest_start() and ring_buffer_nest_end() that will notify the
ring buffer that a trace is about to happen within another trace and that it
is intended, and not to trigger the recursion blocking.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The default clock if timestamps are used in a histogram is "global".
If timestamps aren't used, the clock is irrelevant.
Use the "clock=" param only if you want to override the default
"global" clock for a histogram with timestamps.
Link: http://lkml.kernel.org/r/427bed1389c5d22aa40c3e0683e30cc3d151e260.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Allow tracing code outside of trace.c to access tracing_set_clock().
Some applications may require a particular clock in order to function
properly, such as latency calculations.
Also, add an accessor returning the current clock string.
Link: http://lkml.kernel.org/r/6d1c53e9ee2163f54e1849f5376573f54f0e6009.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
With the addition of variables and actions, it's become necessary to
provide more detailed error information to users about syntax errors.
Add a 'last error' facility accessible via the erroring event's 'hist'
file. Reading the hist file after an error will display more detailed
information about what went wrong, if information is available. This
extended error information will be available until the next hist
trigger command for that event.
# echo xxx > /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
echo: write error: Invalid argument
# cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist
ERROR: Couldn't yyy: zzz
Last command: xxx
Also add specific error messages for variable and action errors.
Link: http://lkml.kernel.org/r/64e9c422fc8aeafcc2f7a3b4328c0cffe7969129.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add support for alias=$somevar where alias can be used as
onmatch.xxx($alias).
Aliases are a way of creating a new name for an existing variable, for
flexibly in making naming more clear in certain cases. For example in
the below the user perhaps feels that using $new_lat in the synthetic
event invocation is opaque or doesn't fit well stylistically with
previous triggers, so creates an alias of $new_lat named $latency and
uses that in the call instead:
# echo 'hist:keys=next_pid:new_lat=common_timestamp.usecs' >
/sys/kernel/debug/tracing/events/sched/sched_switch/trigger
# echo 'hist:keys=pid:latency=$new_lat:
onmatch(sched.sched_switch).wake2($latency,pid)' >
/sys/kernel/debug/tracing/events/synthetic/wake1/trigger
Link: http://lkml.kernel.org/r/ef20a65d921af3a873a6f1e8c71407c926d5586f.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The existing code only allows for one space before and after the 'if'
specifying the filter for a hist trigger. Add code to make that more
permissive as far as whitespace goes. Specifically, we want to allow
spaces in the trigger itself now that we have additional syntax
(onmatch/onmax) where spaces are more natural e.g. spaces after commas
in param lists.
Link: http://lkml.kernel.org/r/1053090c3c308d4f431accdeb59dff4b511d4554.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add an 'onmax(var).save(field,...)' hist trigger action which is
invoked whenever an event exceeds the current maximum.
The end result is that the trace event fields or variables specified
as the onmax.save() params will be saved if 'var' exceeds the current
maximum for that hist trigger entry. This allows context from the
event that exhibited the new maximum to be saved for later reference.
When the histogram is displayed, additional fields displaying the
saved values will be printed.
As an example the below defines a couple of hist triggers, one for
sched_wakeup and another for sched_switch, keyed on pid. Whenever a
sched_wakeup occurs, the timestamp is saved in the entry corresponding
to the current pid, and when the scheduler switches back to that pid,
the timestamp difference is calculated. If the resulting latency
exceeds the current maximum latency, the specified save() values are
saved:
# echo 'hist:keys=pid:ts0=common_timestamp.usecs \
if comm=="cyclictest"' >> \
/sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger
# echo 'hist:keys=next_pid:\
wakeup_lat=common_timestamp.usecs-$ts0:\
onmax($wakeup_lat).save(next_comm,prev_pid,prev_prio,prev_comm) \
if next_comm=="cyclictest"' >> \
/sys/kernel/debug/tracing/events/sched/sched_switch/trigger
When the histogram is displayed, the max value and the saved values
corresponding to the max are displayed following the rest of the
fields:
# cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist
{ next_pid: 3728 } hitcount: 199 \
max: 123 next_comm: cyclictest prev_pid: 0 \
prev_prio: 120 prev_comm: swapper/3
{ next_pid: 3730 } hitcount: 1321 \
max: 15 next_comm: cyclictest prev_pid: 0 \
prev_prio: 120 prev_comm: swapper/1
{ next_pid: 3729 } hitcount: 1973\
max: 25 next_comm: cyclictest prev_pid: 0 \
prev_prio: 120 prev_comm: swapper/0
Totals:
Hits: 3493
Entries: 3
Dropped: 0
Link: http://lkml.kernel.org/r/006907f71b1e839bb059337ec3c496f84fcb71de.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add an 'onmatch(matching.event).<synthetic_event_name>(param list)'
hist trigger action which is invoked with the set of variables or
event fields named in the 'param list'. The result is the generation
of a synthetic event that consists of the values contained in those
variables and/or fields at the time the invoking event was hit.
As an example the below defines a simple synthetic event using a
variable defined on the sched_wakeup_new event, and shows the event
definition with unresolved fields, since the sched_wakeup_new event
with the testpid variable hasn't been defined yet:
# echo 'wakeup_new_test pid_t pid; int prio' >> \
/sys/kernel/debug/tracing/synthetic_events
# cat /sys/kernel/debug/tracing/synthetic_events
wakeup_new_test pid_t pid; int prio
The following hist trigger both defines a testpid variable and
specifies an onmatch() trace action that uses that variable along with
a non-variable field to generate a wakeup_new_test synthetic event
whenever a sched_wakeup_new event occurs, which because of the 'if
comm == "cyclictest"' filter only happens when the executable is
cyclictest:
# echo 'hist:testpid=pid:keys=$testpid:\
onmatch(sched.sched_wakeup_new).wakeup_new_test($testpid, prio) \
if comm=="cyclictest"' >> \
/sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger
Creating and displaying a histogram based on those events is now just
a matter of using the fields and new synthetic event in the
tracing/events/synthetic directory, as usual:
# echo 'hist:keys=pid,prio:sort=pid,prio' >> \
/sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/trigger
Link: http://lkml.kernel.org/r/8c2a574bcb7530c876629c901ecd23911b14afe8.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Rajvi Jingar <rajvi.jingar@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Users should be able to directly specify event fields in hist trigger
'actions' rather than being forced to explicitly create a variable for
that purpose.
Add support allowing fields to be used directly in actions, which
essentially does just that - creates 'invisible' variables for each
bare field specified in an action. If a bare field refers to a field
on another (matching) event, it even creates a special histogram for
the purpose (since variables can't be defined on an existing histogram
after histogram creation).
Here's a simple example that demonstrates both. Basically the
onmatch() action creates a list of variables corresponding to the
parameters of the synthetic event to be generated, and then uses those
values to generate the event. So for the wakeup_latency synthetic
event 'call' below the first param, $wakeup_lat, is a variable defined
explicitly on sched_switch, where 'next_pid' is just a normal field on
sched_switch, and prio is a normal field on sched_waking.
Since the mechanism works on variables, those two normal fields just
have 'invisible' variables created internally for them. In the case of
'prio', which is on another event, we actually need to create an
additional hist trigger and define the invisible variable on that, since
once a hist trigger is defined, variables can't be added to it later.
echo 'wakeup_latency u64 lat; pid_t pid; int prio' >>
/sys/kernel/debug/tracing/synthetic_events
echo 'hist:keys=pid:ts0=common_timestamp.usecs >>
/sys/kernel/debug/tracing/events/sched/sched_waking/trigger
echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:
onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,next_pid,prio)
>> /sys/kernel/debug/tracing/events/sched/sched_switch/trigger
Link: http://lkml.kernel.org/r/8e8dcdac1ea180ed7a3689e1caeeccede9dc42b3.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Synthetic events are user-defined events generated from hist trigger
variables saved from one or more other events.
To define a synthetic event, the user writes a simple specification
consisting of the name of the new event along with one or more
variables and their type(s), to the tracing/synthetic_events file.
For instance, the following creates a new event named 'wakeup_latency'
with 3 fields: lat, pid, and prio:
# echo 'wakeup_latency u64 lat; pid_t pid; int prio' >> \
/sys/kernel/debug/tracing/synthetic_events
Reading the tracing/synthetic_events file lists all the
currently-defined synthetic events, in this case the event we defined
above:
# cat /sys/kernel/debug/tracing/synthetic_events
wakeup_latency u64 lat; pid_t pid; int prio
At this point, the synthetic event is ready to use, and a histogram
can be defined using it:
# echo 'hist:keys=pid,prio,lat.log2:sort=pid,lat' >> \
/sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger
The new event is created under the tracing/events/synthetic/ directory
and looks and behaves just like any other event:
# ls /sys/kernel/debug/tracing/events/synthetic/wakeup_latency
enable filter format hist id trigger
Although a histogram can be defined for it, nothing will happen until
an action tracing that event via the trace_synth() function occurs.
The trace_synth() function is very similar to all the other trace_*
invocations spread throughout the kernel, except in this case the
trace_ function and its corresponding tracepoint isn't statically
generated but defined by the user at run-time.
How this can be automatically hooked up via a hist trigger 'action' is
discussed in a subsequent patch.
Link: http://lkml.kernel.org/r/c68df2284b7d172669daf9be29db62ad49bbc559.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[fix noderef.cocci warnings, sizeof pointer for kcalloc of event->fields]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a hook for executing extra actions whenever a histogram entry is
added or updated.
The default 'action' when a hist entry is added to a histogram is to
update the set of values associated with it. Some applications may
want to perform additional actions at that point, such as generate
another event, or compare and save a maximum.
Add a simple framework for doing that; specific actions will be
implemented on top of it in later patches.
Link: http://lkml.kernel.org/r/9482ba6a3eaf5ca6e60954314beacd0e25c05b24.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add the necessary infrastructure to allow the variables defined on one
event to be referenced in another. This allows variables set by a
previous event to be referenced and used in expressions combining the
variable values saved by that previous event and the event fields of
the current event. For example, here's how a latency can be
calculated and saved into yet another variable named 'wakeup_lat':
# echo 'hist:keys=pid,prio:ts0=common_timestamp ...
# echo 'hist:keys=next_pid:wakeup_lat=common_timestamp-$ts0 ...
In the first event, the event's timetamp is saved into the variable
ts0. In the next line, ts0 is subtracted from the second event's
timestamp to produce the latency.
Further users of variable references will be described in subsequent
patches, such as for instance how the 'wakeup_lat' variable above can
be displayed in a latency histogram.
Link: http://lkml.kernel.org/r/b1d3e6975374e34d501ff417c20189c3f9b2c7b8.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Some accessor functions, such as for variable references, require
access to a corrsponding tracing_map_elt.
Add a tracing_map_elt param to the function signature and update the
accessor functions accordingly.
Link: http://lkml.kernel.org/r/e0f292b068e9e4948da1d5af21b5ae0efa9b5717.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Up until now, hist triggers only needed per-element support for saving
'comm' data, which was saved directly as a private data pointer.
In anticipation of the need to save other data besides 'comm', add a
new hist_elt_data struct for the purpose, and switch the current
'comm'-related code over to that.
Link: http://lkml.kernel.org/r/4502c338c965ddf5fc19fb1ec4764391e001ed4b.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add support for simple addition, subtraction, and unary expressions
(-(expr) and expr, where expr = b-a, a+b, a+b+c) to hist triggers, in
order to support a minimal set of useful inter-event calculations.
These operations are needed for calculating latencies between events
(timestamp1-timestamp0) and for combined latencies (latencies over 3
or more events).
In the process, factor out some common code from key and value
parsing.
Link: http://lkml.kernel.org/r/9a9308ead4fe32a433d9c7e95921fb798394f6b2.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
[kbuild test robot fix, add static to parse_atom()]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
[ Replaced '//' comments with normal /* */ comments ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Named triggers must also have the same set of variables in order to be
considered compatible - update the trigger match test to account for
that.
The reason for this requirement is that named triggers with variables
are meant to allow one or more events to set the same variable.
Link: http://lkml.kernel.org/r/a17eae6328a99917f9d5c66129c9fcd355279ee9.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add support for saving the value of a current event's event field by
assigning it to a variable that can be read by a subsequent event.
The basic syntax for saving a variable is to simply prefix a unique
variable name not corresponding to any keyword along with an '=' sign
to any event field.
Both keys and values can be saved and retrieved in this way:
# echo 'hist:keys=next_pid:vals=$ts0:ts0=common_timestamp ...
# echo 'hist:timer_pid=common_pid:key=$timer_pid ...'
If a variable isn't a key variable or prefixed with 'vals=', the
associated event field will be saved in a variable but won't be summed
as a value:
# echo 'hist:keys=next_pid:ts1=common_timestamp:...
Multiple variables can be assigned at the same time:
# echo 'hist:keys=pid:vals=$ts0,$b,field2:ts0=common_timestamp,b=field1 ...
Multiple (or single) variables can also be assigned at the same time
using separate assignments:
# echo 'hist:keys=pid:vals=$ts0:ts0=common_timestamp:b=field1:c=field2 ...
Variables set as above can be used by being referenced from another
event, as described in a subsequent patch.
Link: http://lkml.kernel.org/r/fc93c4944d9719dbcb1d0067be627d44e98e2adc.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Appending .usecs onto a common_timestamp field will cause the
timestamp value to be in microseconds instead of the default
nanoseconds. A typical latency histogram using usecs would look like
this:
# echo 'hist:keys=pid,prio:ts0=common_timestamp.usecs ...
# echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0 ...
This also adds an external trace_clock_in_ns() to trace.c for the
timestamp conversion.
Link: http://lkml.kernel.org/r/4e813705a170b3e13e97dc3135047362fb1a39f3.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In order to allow information to be passed between trace events, add
support for per-element variables to tracing_map. This provides a
means for histograms to associate a value or values with an entry when
it's saved or updated, and retrieved by a subsequent event occurrences.
Variables can be set using tracing_map_set_var() and read using
tracing_map_read_var(). tracing_map_var_set() returns true or false
depending on whether or not the variable has been set or not, which is
important for event-matching applications.
tracing_map_read_var_once() reads the variable and resets it to the
'unset' state, implementing read-once variables, which are also
important for event-matching uses.
Link: http://lkml.kernel.org/r/7fa001108252556f0c6dd9d63145eabfe3370d1a.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add support for a timestamp event field. This is actually a 'pseudo-'
event field in that it behaves like it's part of the event record, but
is really part of the corresponding ring buffer event.
To make use of the timestamp field, users can specify
"common_timestamp" as a field name for any histogram. Note that this
doesn't make much sense on its own either as either a key or value,
but needs to be supported even so, since follow-on patches will add
support for making use of this field in time deltas. The
common_timestamp 'field' is not a bona fide event field - so you won't
find it in the event description - but rather it's a synthetic field
that can be used like a real field.
Note that the use of this field requires the ring buffer be put into
'absolute timestamp' mode, which saves the complete timestamp for each
event rather than an offset. This mode will be enabled if and only if
a histogram makes use of the "common_timestamp" field.
Link: http://lkml.kernel.org/r/97afbd646ed146e26271f3458b4b33e16d7817c2.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
[kasan use-after-free fix]
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a new option flag indicating whether or not the ring buffer is in
'absolute timestamp' mode.
Currently this is only set/unset by hist triggers that make use of a
common_timestamp. As such, there's no reason to make this writeable
for users - its purpose is only to allow users to determine
unequivocally whether or not the ring buffer is in that mode (although
absolute timestamps can coexist with the normal delta timestamps, when
the ring buffer is in absolute mode, timestamps written while absolute
mode is in effect take up more space in the buffer, and are not as
efficient).
Link: http://lkml.kernel.org/r/e8aa7b1cde1cf15014e66545d06ac6ef2ebba456.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
RINGBUF_TYPE_TIME_STAMP is defined but not used, and from what I can
gather was reserved for something like an absolute timestamp feature
for the ring buffer, if not a complete replacement of the current
time_delta scheme.
This code redefines RINGBUF_TYPE_TIME_STAMP to implement absolute time
stamps. Another way to look at it is that it essentially forces
extended time_deltas for all events.
The motivation for doing this is to enable time_deltas that aren't
dependent on previous events in the ring buffer, making it feasible to
use the ring_buffer_event timetamps in a more random-access way, for
purposes other than serial event printing.
To set/reset this mode, use tracing_set_timestamp_abs() from the
previous interface patch.
Link: http://lkml.kernel.org/r/477b362dba1ce7fab9889a1a8e885a62c472f041.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Define a new function, tracing_set_time_stamp_abs(), which can be used
to enable or disable the use of absolute timestamps rather than time
deltas for a trace array.
Only the interface is added here; a subsequent patch will add the
underlying implementation.
Link: http://lkml.kernel.org/r/ce96119de44c7fe0ee44786d15254e9b493040d3.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Baohong Liu <baohong.liu@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
We now have the logic to detect and remove duplicates in the
tracing_map hash table. The code which merges duplicates in the
histogram is redundant now. So, modify this code just to detect
duplicates. The duplication detection code is still kept to ensure
that any rare race condition which might cause duplicates does not go
unnoticed.
Link: http://lkml.kernel.org/r/55215cf59e2674391bdaf772fdafc4c393352b03.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
A duplicate in the tracing_map hash table is when 2 different entries
have the same key and, as a result, the key_hash. This is possible due
to a race condition in the algorithm. This race condition is inherent to
the algorithm and not a bug. This was fine because, until now, we were
only interested in the sum of all the values related to a particular
key (the duplicates are dealt with in tracing_map_sort_entries()). But,
with the inclusion of variables[1], we are interested in individual
values. So, it will not be clear what value to choose when
there are duplicates. So, the duplicates need to be removed.
The duplicates can occur in the code in the following scenarios:
- A thread is in the process of adding a new element. It has
successfully executed cmpxchg() and inserted the key. But, it is still
not done acquiring the trace_map_elt struct, populating it and storing
the pointer to the struct in the value field of tracing_map hash table.
If another thread comes in at this time and wants to add an element with
the same key, it will not see the current element and add a new one.
- There are multiple threads trying to execute cmpxchg at the same time,
one of the threads will succeed and the others will fail. The ones which
fail will go ahead increment 'idx' and add a new element there creating
a duplicate.
This patch detects and avoids the first condition by asking the thread
which detects the duplicate to loop one more time. There is also a
possibility of infinite loop if the thread which is trying to insert
goes to sleep indefinitely and the one which is trying to insert a new
element detects a duplicate. Which is why, the thread loops for
map_size iterations before returning NULL.
The second scenario is avoided by preventing the threads which failed
cmpxchg() from incrementing idx. This way, they will loop
around and check if the thread which succeeded in executing cmpxchg()
had the same key.
[1] http://lkml.kernel.org/r/cover.1498510759.git.tom.zanussi@linux.intel.com
Link: http://lkml.kernel.org/r/e178e89ec399240331d383bd5913d649713110f4.1516069914.git.tom.zanussi@linux.intel.com
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit adds new field "addr" to bpf_perf_event_data which could be
read and used by bpf programs attached to perf events. The value of the
field is copied from bpf_perf_event_data_kern.addr and contains the
address value recorded by specifying sample_type with PERF_SAMPLE_ADDR
when calling perf_event_open.
Signed-off-by: Teng Qin <qinteng@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
syzkaller tried to perform a prog query in perf_event_query_prog_array()
where struct perf_event_query_bpf had an ids_len of 1,073,741,353 and
thus causing a warning due to failed kcalloc() allocation out of the
bpf_prog_array_copy_to_user() helper. Given we cannot attach more than
64 programs to a perf event, there's no point in allowing huge ids_len.
Therefore, allow a buffer that would fix the maximum number of ids and
also add a __GFP_NOWARN to the temporary ids buffer.
Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Fixes: 0911287ce3 ("bpf: fix bpf_prog_array_copy_to_user() issues")
Reported-by: syzbot+cab5816b0edbabf598b3@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:
for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done
with de-mangling cleanups yet to come.
NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.
The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
as well as the removing of function probes.
This fixes the code with Al's suggestions. I also added a few selftests
to test the broken cases such that they wont happen again.
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Merge tag 'trace-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Al Viro discovered some breakage with the parsing of the
set_ftrace_filter as well as the removing of function probes.
This fixes the code with Al's suggestions. I also added a few
selftests to test the broken cases such that they wont happen
again"
* tag 'trace-v4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests/ftrace: Add more tests for removing of function probes
selftests/ftrace: Add some missing glob checks
selftests/ftrace: Have reset_ftrace_filter handle multiple instances
selftests/ftrace: Have reset_ftrace_filter handle modules
tracing: Fix parsing of globs with a wildcard at the beginning
ftrace: Remove incorrect setting of glob search field
Al Viro reported:
For substring - sure, but what about something like "*a*b" and "a*b"?
AFAICS, filter_parse_regex() ends up with identical results in both
cases - MATCH_GLOB and *search = "a*b". And no way for the caller
to tell one from another.
Testing this with the following:
# cd /sys/kernel/tracing
# echo '*raw*lock' > set_ftrace_filter
bash: echo: write error: Invalid argument
With this patch:
# echo '*raw*lock' > set_ftrace_filter
# cat set_ftrace_filter
_raw_read_trylock
_raw_write_trylock
_raw_read_unlock
_raw_spin_unlock
_raw_write_unlock
_raw_spin_trylock
_raw_spin_lock
_raw_write_lock
_raw_read_lock
Al recommended not setting the search buffer to skip the first '*' unless we
know we are not using MATCH_GLOB. This implements his suggested logic.
Link: http://lkml.kernel.org/r/20180127170748.GF13338@ZenIV.linux.org.uk
Cc: stable@vger.kernel.org
Fixes: 60f1d5e3ba ("ftrace: Support full glob matching")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Suggsted-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
__unregister_ftrace_function_probe() will incorrectly parse the glob filter
because it resets the search variable that was setup by filter_parse_regex().
Al Viro reported this:
After that call of filter_parse_regex() we could have func_g.search not
equal to glob only if glob started with '!' or '*'. In the former case
we would've buggered off with -EINVAL (not = 1). In the latter we
would've set func_g.search equal to glob + 1, calculated the length of
that thing in func_g.len and proceeded to reset func_g.search back to
glob.
Suppose the glob is e.g. *foo*. We end up with
func_g.type = MATCH_MIDDLE_ONLY;
func_g.len = 3;
func_g.search = "*foo";
Feeding that to ftrace_match_record() will not do anything sane - we
will be looking for names containing "*foo" (->len is ignored for that
one).
Link: http://lkml.kernel.org/r/20180127031706.GE13338@ZenIV.linux.org.uk
Cc: stable@vger.kernel.org
Fixes: 3ba0092971 ("ftrace: Introduce ftrace_glob structure")
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This patch adds perf_uprobe support with similar pattern as previous
patch (for kprobe).
Two functions, create_local_trace_uprobe() and
destroy_local_trace_uprobe(), are created so a uprobe can be created
and attached to the file descriptor created by perf_event_open().
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <davem@davemloft.net>
Cc: <kernel-team@fb.com>
Cc: <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206224518.3598254-7-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A new PMU type, perf_kprobe is added. Based on attr from perf_event_open(),
perf_kprobe creates a kprobe (or kretprobe) for the perf_event. This
kprobe is private to this perf_event, and thus not added to global
lists, and not available in tracefs.
Two functions, create_local_trace_kprobe() and
destroy_local_trace_kprobe() are added to created and destroy these
local trace_kprobe.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Yonghong Song <yhs@fb.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Cc: <daniel@iogearbox.net>
Cc: <davem@davemloft.net>
Cc: <kernel-team@fb.com>
Cc: <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171206224518.3598254-6-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There's not much changes for the tracing system this release.
Mostly small clean ups and fixes.
The biggest change is to how bprintf works. bprintf is used by
trace_printk() to just save the format and args of a printf call,
and the formatting is done when the trace buffer is read. This is
done to keep the formatting out of the fast path (this was recommended
by you). The issue is when arguments are de-referenced.
If a pointer is saved, and the format has something like "%*pbl",
when the buffer is read, it will de-reference the argument then.
The problem is if the data no longer exists. This can cause the
kernel to oops.
The fix for this was to make these de-reference pointes do
the formatting at the time it is called (the fast path), as
this guarantees that the data exists (and doesn't change later)
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Merge tag 'trace-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"There's not much changes for the tracing system this release. Mostly
small clean ups and fixes.
The biggest change is to how bprintf works. bprintf is used by
trace_printk() to just save the format and args of a printf call, and
the formatting is done when the trace buffer is read. This is done to
keep the formatting out of the fast path (this was recommended by
you). The issue is when arguments are de-referenced.
If a pointer is saved, and the format has something like "%*pbl", when
the buffer is read, it will de-reference the argument then. The
problem is if the data no longer exists. This can cause the kernel to
oops.
The fix for this was to make these de-reference pointes do the
formatting at the time it is called (the fast path), as this
guarantees that the data exists (and doesn't change later)"
* tag 'trace-v4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
vsprintf: Do not have bprintf dereference pointers
ftrace: Mark function tracer test functions noinline/noclone
trace_uprobe: Display correct offset in uprobe_events
tracing: Make sure the parsed string always terminates with '\0'
tracing: Clear parser->idx if only spaces are read
tracing: Detect the string nul character when parsing user input string
Pull networking updates from David Miller:
1) Significantly shrink the core networking routing structures. Result
of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf
2) Add netdevsim driver for testing various offloads, from Jakub
Kicinski.
3) Support cross-chip FDB operations in DSA, from Vivien Didelot.
4) Add a 2nd listener hash table for TCP, similar to what was done for
UDP. From Martin KaFai Lau.
5) Add eBPF based queue selection to tun, from Jason Wang.
6) Lockless qdisc support, from John Fastabend.
7) SCTP stream interleave support, from Xin Long.
8) Smoother TCP receive autotuning, from Eric Dumazet.
9) Lots of erspan tunneling enhancements, from William Tu.
10) Add true function call support to BPF, from Alexei Starovoitov.
11) Add explicit support for GRO HW offloading, from Michael Chan.
12) Support extack generation in more netlink subsystems. From Alexander
Aring, Quentin Monnet, and Jakub Kicinski.
13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From
Russell King.
14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso.
15) Many improvements and simplifications to the NFP driver bpf JIT,
from Jakub Kicinski.
16) Support for ipv6 non-equal cost multipath routing, from Ido
Schimmel.
17) Add resource abstration to devlink, from Arkadi Sharshevsky.
18) Packet scheduler classifier shared filter block support, from Jiri
Pirko.
19) Avoid locking in act_csum, from Davide Caratti.
20) devinet_ioctl() simplifications from Al viro.
21) More TCP bpf improvements from Lawrence Brakmo.
22) Add support for onlink ipv6 route flag, similar to ipv4, from David
Ahern.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits)
tls: Add support for encryption using async offload accelerator
ip6mr: fix stale iterator
net/sched: kconfig: Remove blank help texts
openvswitch: meter: Use 64-bit arithmetic instead of 32-bit
tcp_nv: fix potential integer overflow in tcpnv_acked
r8169: fix RTL8168EP take too long to complete driver initialization.
qmi_wwan: Add support for Quectel EP06
rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK
ipmr: Fix ptrdiff_t print formatting
ibmvnic: Wait for device response when changing MAC
qlcnic: fix deadlock bug
tcp: release sk_frag.page in tcp_disconnect
ipv4: Get the address of interface correctly.
net_sched: gen_estimator: fix lockdep splat
net: macb: Handle HRESP error
net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring
ipv6: addrconf: break critical section in addrconf_verify_rtnl()
ipv6: change route cache aging logic
i40e/i40evf: Update DESC_NEEDED value to reflect larger value
bnxt_en: cleanup DIM work on device shutdown
...
Pull poll annotations from Al Viro:
"This introduces a __bitwise type for POLL### bitmap, and propagates
the annotations through the tree. Most of that stuff is as simple as
'make ->poll() instances return __poll_t and do the same to local
variables used to hold the future return value'.
Some of the obvious brainos found in process are fixed (e.g. POLLIN
misspelled as POLL_IN). At that point the amount of sparse warnings is
low and most of them are for genuine bugs - e.g. ->poll() instance
deciding to return -EINVAL instead of a bitmap. I hadn't touched those
in this series - it's large enough as it is.
Another problem it has caught was eventpoll() ABI mess; select.c and
eventpoll.c assumed that corresponding POLL### and EPOLL### were
equal. That's true for some, but not all of them - EPOLL### are
arch-independent, but POLL### are not.
The last commit in this series separates userland POLL### values from
the (now arch-independent) kernel-side ones, converting between them
in the few places where they are copied to/from userland. AFAICS, this
is the least disruptive fix preserving poll(2) ABI and making epoll()
work on all architectures.
As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
it will trigger only on what would've triggered EPOLLWRBAND on other
architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
at all on sparc. With this patch they should work consistently on all
architectures"
* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
make kernel-side POLL... arch-independent
eventpoll: no need to mask the result of epi_item_poll() again
eventpoll: constify struct epoll_event pointers
debugging printk in sg_poll() uses %x to print POLL... bitmap
annotate poll(2) guts
9p: untangle ->poll() mess
->si_band gets POLL... bitmap stored into a user-visible long field
ring_buffer_poll_wait() return value used as return value of ->poll()
the rest of drivers/*: annotate ->poll() instances
media: annotate ->poll() instances
fs: annotate ->poll() instances
ipc, kernel, mm: annotate ->poll() instances
net: annotate ->poll() instances
apparmor: annotate ->poll() instances
tomoyo: annotate ->poll() instances
sound: annotate ->poll() instances
acpi: annotate ->poll() instances
crypto: annotate ->poll() instances
block: annotate ->poll() instances
x86: annotate ->poll() instances
...
Pull RCU updates from Ingo Molnar:
"The main RCU changes in this cycle were:
- Updates to use cond_resched() instead of cond_resched_rcu_qs()
where feasible (currently everywhere except in kernel/rcu and in
kernel/torture.c). Also a couple of fixes to avoid sending IPIs to
offline CPUs.
- Updates to simplify RCU's dyntick-idle handling.
- Updates to remove almost all uses of smp_read_barrier_depends() and
read_barrier_depends().
- Torture-test updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
torture: Save a line in stutter_wait(): while -> for
torture: Eliminate torture_runnable and perf_runnable
torture: Make stutter less vulnerable to compilers and races
locking/locktorture: Fix num reader/writer corner cases
locking/locktorture: Fix rwsem reader_delay
torture: Place all torture-test modules in one MAINTAINERS group
rcutorture/kvm-build.sh: Skip build directory check
rcutorture: Simplify functions.sh include path
rcutorture: Simplify logging
rcutorture/kvm-recheck-*: Improve result directory readability check
rcutorture/kvm.sh: Support execution from any directory
rcutorture/kvm.sh: Use consistent help text for --qemu-args
rcutorture/kvm.sh: Remove unused variable, `alldone`
rcutorture: Remove unused script, config2frag.sh
rcutorture/configinit: Fix build directory error message
rcutorture: Preempt RCU-preempt readers more vigorously
torture: Reduce #ifdefs for preempt_schedule()
rcu: Remove have_rcu_nocb_mask from tree_plugin.h
rcu: Add comment giving debug strategy for double call_rcu()
tracing, rcu: Hide trace event rcu_nocb_wake when not used
...
The ftrace function tracer self tests calls some functions to verify
the get traced. This relies on them not being inlined. Previously
this was ensured by putting them into another file, but with LTO
the compiler can inline across files, which makes the tests fail.
Mark these functions as noinline and noclone.
Link: http://lkml.kernel.org/r/20171221233732.31896-1-andi@firstfloor.org
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Recently, how the pointers being printed with %p has been changed
by commit ad67b74d24 ("printk: hash addresses printed with %p").
This is causing a regression while showing offset in the
uprobe_events file. Instead of %p, use %px to display offset.
Before patch:
# perf probe -vv -x /tmp/a.out main
Opening /sys/kernel/debug/tracing//uprobe_events write=1
Writing event: p:probe_a/main /tmp/a.out:0x58c
# cat /sys/kernel/debug/tracing/uprobe_events
p:probe_a/main /tmp/a.out:0x0000000049a0f352
After patch:
# cat /sys/kernel/debug/tracing/uprobe_events
p:probe_a/main /tmp/a.out:0x000000000000058c
Link: http://lkml.kernel.org/r/20180106054246.15375-1-ravi.bangoria@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Fixes: ad67b74d24 ("printk: hash addresses printed with %p")
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Always mark the parsed string with a terminated nul '\0' character. This removes
the need for the users to have to append the '\0' before using the parsed string.
Link: http://lkml.kernel.org/r/1516093350-12045-4-git-send-email-changbin.du@intel.com
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If only spaces were read while parsing the next string, then parser->idx should be
cleared in order to make trace_parser_loaded() return false.
Link: http://lkml.kernel.org/r/1516093350-12045-3-git-send-email-changbin.du@intel.com
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
User space can pass in a C nul character '\0' along with its input. The
function trace_get_user() will try to process it as a normal character,
and that will fail to parse.
open("/sys/kernel/debug/tracing//set_ftrace_pid", O_WRONLY|O_TRUNC) = 3
write(3, " \0", 2) = -1 EINVAL (Invalid argument)
while parse can handle spaces, so below works.
$ echo "" > set_ftrace_pid
$ echo " " > set_ftrace_pid
$ echo -n " " > set_ftrace_pid
Have the parser stop on '\0' and cease any further parsing. Only process
the characters up to the nul '\0' character and do not process it.
Link: http://lkml.kernel.org/r/1516093350-12045-2-git-send-email-changbin.du@intel.com
Acked-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
With the addition of ORC unwinder and FRAME POINTER unwinder, the stack
trace skipping requirements have changed.
I went through the tracing stack trace dumps with ORC and with frame
pointers and recalculated the proper values.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The function tracer can create a dynamically allocated trampoline that is
called by the function mcount or fentry hook that is used to call the
function callback that is registered. The problem is that the orc undwinder
will bail if it encounters one of these trampolines. This breaks the stack
trace of function callbacks, which include the stack tracer and setting the
stack trace for individual functions.
Since these dynamic trampolines are basically copies of the static ftrace
trampolines defined in ftrace_*.S, we do not need to create new orc entries
for the dynamic trampolines. Finding the return address on the stack will be
identical as the functions that were copied to create the dynamic
trampolines. When encountering a ftrace dynamic trampoline, we can just use
the orc entry of the ftrace static function that was copied for that
trampoline.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2018-01-19
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) bpf array map HW offload, from Jakub.
2) support for bpf_get_next_key() for LPM map, from Yonghong.
3) test_verifier now runs loaded programs, from Alexei.
4) xdp cpumap monitoring, from Jesper.
5) variety of tests, cleanups and small x64 JIT optimization, from Daniel.
6) user space can now retrieve HW JITed program, from Jiong.
Note there is a minor conflict between Russell's arm32 JIT fixes
and removal of bpf_jit_enable variable by Daniel which should
be resolved by keeping Russell's comment and removing that variable.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The BPF verifier conflict was some minor contextual issue.
The TUN conflict was less trivial. Cong Wang fixed a memory leak of
tfile->tx_array in 'net'. This is an skb_array. But meanwhile in
net-next tun changed tfile->tx_arry into tfile->tx_ring which is a
ptr_ring.
Signed-off-by: David S. Miller <davem@davemloft.net>
Since enums do not get converted by the TRACE_EVENT macro into their values,
the event format displaces the enum name and not the value. This breaks
tools like perf and trace-cmd that need to interpret the raw binary data. To
solve this, an enum map was created to convert these enums into their actual
numbers on boot up. This is done by TRACE_EVENTS() adding a
TRACE_DEFINE_ENUM() macro.
Some enums were not being converted. This was caused by an optization that
had a bug in it.
All calls get checked against this enum map to see if it should be converted
or not, and it compares the call's system to the system that the enum map
was created under. If they match, then they call is processed.
To cut down on the number of iterations needed to find the maps with a
matching system, since calls and maps are grouped by system, when a match is
made, the index into the map array is saved, so that the next call, if it
belongs to the same system as the previous call, could start right at that
array index and not have to scan all the previous arrays.
The problem was, the saved index was used as the variable to know if this is
a call in a new system or not. If the index was zero, it was assumed that
the call is in a new system and would keep incrementing the saved index
until it found a matching system. The issue arises when the first matching
system was at index zero. The next map, if it belonged to the same system,
would then think it was the first match and increment the index to one. If
the next call belong to the same system, it would begin its search of the
maps off by one, and miss the first enum that should be converted. This left
a single enum not converted properly.
Also add a comment to describe exactly what that index was for. It took me a
bit too long to figure out what I was thinking when debugging this issue.
Link: http://lkml.kernel.org/r/717BE572-2070-4C1E-9902-9F2E0FEDA4F8@oracle.com
Cc: stable@vger.kernel.org
Fixes: 0c564a538a ("tracing: Add TRACE_DEFINE_ENUM() macro to map enums to their values")
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Teste-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In bringing back the context checks, the code checks first if its normal
(non-interrupt) context, and then for NMI then IRQ then softirq. The final
check is redundant. Since the if branch is only hit if the context is one of
NMI, IRQ, or SOFTIRQ, if it's not NMI or IRQ there's no reason to check if
it is SOFTIRQ. The current code returns the same result even if its not a
SOFTIRQ. Which is confusing.
pc & SOFTIRQ_OFFSET ? 2 : RB_CTX_SOFTIRQ
Is redundant as RB_CTX_SOFTIRQ *is* 2!
Fixes: a0e3a18f4b ("ring-buffer: Bring back context level recursive checks")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently, for bpf_trace_printk helper, fake ip address 0x1
is used with comments saying that fake ip will not be printed.
This is indeed true for 4.12 and earlier version, but for
4.13 and later version, the ip address will be printed if
it cannot be resolved with kallsym. Running samples/bpf/tracex5
program and you will have the following in the debugfs
trace_pipe output:
...
<...>-1819 [003] .... 443.497877: 0x00000001: mmap
<...>-1819 [003] .... 443.498289: 0x00000001: syscall=102 (one of get/set uid/pid/gid)
...
The kernel commit changed this behavior is:
commit feaf1283d1
Author: Steven Rostedt (VMware) <rostedt@goodmis.org>
Date: Thu Jun 22 17:04:55 2017 -0400
tracing: Show address when function names are not found
...
This patch changed the comment and also altered the fake ip
address to 0x0 as users may think 0x1 has some special meaning
while it doesn't. The new output:
...
<...>-1799 [002] .... 25.953576: 0: mmap
<...>-1799 [002] .... 25.953865: 0: read(fd=0, buf=00000000053936b5, size=512)
...
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
I regularly get 50 MB - 60 MB files during kernel randconfig builds.
These large files mostly contain (many repeats of; e.g., 124,594):
In file included from ../include/linux/string.h:6:0,
from ../include/linux/uuid.h:20,
from ../include/linux/mod_devicetable.h:13,
from ../scripts/mod/devicetable-offsets.c:3:
../include/linux/compiler.h:64:4: warning: '______f' is static but declared in inline function 'strcpy' which is not static [enabled by default]
______f = { \
^
../include/linux/compiler.h:56:23: note: in expansion of macro '__trace_if'
^
../include/linux/string.h:425:2: note: in expansion of macro 'if'
if (p_size == (size_t)-1 && q_size == (size_t)-1)
^
This only happens when CONFIG_FORTIFY_SOURCE=y and
CONFIG_PROFILE_ALL_BRANCHES=y, so prevent PROFILE_ALL_BRANCHES if
FORTIFY_SOURCE=y.
Link: http://lkml.kernel.org/r/9199446b-a141-c0c3-9678-a3f9107f2750@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit 1a149d7d3f ("ring-buffer: Rewrite trace_recursive_(un)lock() to be
simpler") replaced the context level recursion checks with a simple counter.
This would prevent the ring buffer code from recursively calling itself more
than the max number of contexts that exist (Normal, softirq, irq, nmi). But
this change caused a lockup in a specific case, which was during suspend and
resume using a global clock. Adding a stack dump to see where this occurred,
the issue was in the trace global clock itself:
trace_buffer_lock_reserve+0x1c/0x50
__trace_graph_entry+0x2d/0x90
trace_graph_entry+0xe8/0x200
prepare_ftrace_return+0x69/0xc0
ftrace_graph_caller+0x78/0xa8
queued_spin_lock_slowpath+0x5/0x1d0
trace_clock_global+0xb0/0xc0
ring_buffer_lock_reserve+0xf9/0x390
The function graph tracer traced queued_spin_lock_slowpath that was called
by trace_clock_global. This pointed out that the trace_clock_global() is not
reentrant, as it takes a spin lock. It depended on the ring buffer recursive
lock from letting that happen.
By removing the context detection and adding just a max number of allowable
recursions, it allowed the trace_clock_global() to be entered again and try
to retake the spinlock it already held, causing a deadlock.
Fixes: 1a149d7d3f ("ring-buffer: Rewrite trace_recursive_(un)lock() to be simpler")
Reported-by: David Weinehall <david.weinehall@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since error-injection framework is not limited to be used
by kprobes, nor bpf. Other kernel subsystems can use it
freely for checking safeness of error-injection, e.g.
livepatch, ftrace etc.
So this separate error-injection framework from kprobes.
Some differences has been made:
- "kprobe" word is removed from any APIs/structures.
- BPF_ALLOW_ERROR_INJECTION() is renamed to
ALLOW_ERROR_INJECTION() since it is not limited for BPF too.
- CONFIG_FUNCTION_ERROR_INJECTION is the config item of this
feature. It is automatically enabled if the arch supports
error injection feature for kprobe or ftrace etc.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Compare instruction pointer with original one on the
stack instead using per-cpu bpf_kprobe_override flag.
This patch also consolidates reset_current_kprobe() and
preempt_enable_no_resched() blocks. Those can be done
in one place.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Check whether error injectable event is on function entry or not.
Currently it checks the event is ftrace-based kprobes or not,
but that is wrong. It should check if the event is on the entry
of target function. Since error injection will override a function
to just return with modified return value, that operation must
be done before the target function starts making stackframe.
As a side effect, bpf error injection is no need to depend on
function-tracer. It can work with sw-breakpoint based kprobe
events too.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull RCU updates from Paul E. McKenney:
- Updates to use cond_resched() instead of cond_resched_rcu_qs()
where feasible (currently everywhere except in kernel/rcu and
in kernel/torture.c). Also a couple of fixes to avoid sending
IPIs to offline CPUs.
- Updates to simplify RCU's dyntick-idle handling.
- Updates to remove almost all uses of smp_read_barrier_depends()
and read_barrier_depends().
- Miscellaneous fixes.
- Torture-test updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
net/ipv6/ip6_gre.c is a case of parallel adds.
include/trace/events/tcp.h is a little bit more tricky. The removal
of in-trace-macro ifdefs in 'net' paralleled with moving
show_tcp_state_name and friends over to include/trace/events/sock.h
in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Jing Xia and Chunyan Zhang reported that on failing to allocate part of the
tracing buffer, memory is freed, but the pointers that point to them are not
initialized back to NULL, and later paths may try to free the freed memory
again. Jing and Chunyan fixed one of the locations that does this, but
missed a spot.
Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com
Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Reported-by: Jing Xia <jing.xia@spreadtrum.com>
Reported-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Double free of the ring buffer happens when it fails to alloc new
ring buffer instance for max_buffer if TRACER_MAX_TRACE is configured.
The root cause is that the pointer is not set to NULL after the buffer
is freed in allocate_trace_buffers(), and the freeing of the ring
buffer is invoked again later if the pointer is not equal to Null,
as:
instance_mkdir()
|-allocate_trace_buffers()
|-allocate_trace_buffer(tr, &tr->trace_buffer...)
|-allocate_trace_buffer(tr, &tr->max_buffer...)
// allocate fail(-ENOMEM),first free
// and the buffer pointer is not set to null
|-ring_buffer_free(tr->trace_buffer.buffer)
// out_free_tr
|-free_trace_buffers()
|-free_trace_buffer(&tr->trace_buffer);
//if trace_buffer is not null, free again
|-ring_buffer_free(buf->buffer)
|-rb_free_cpu_buffer(buffer->buffers[cpu])
// ring_buffer_per_cpu is null, and
// crash in ring_buffer_per_cpu->pages
Link: http://lkml.kernel.org/r/20171226071253.8968-1-chunyan.zhang@spreadtrum.com
Cc: stable@vger.kernel.org
Fixes: 737223fbca ("tracing: Consolidate buffer allocation code")
Signed-off-by: Jing Xia <jing.xia@spreadtrum.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@spreadtrum.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
To free the reader page that is allocated with ring_buffer_alloc_read_page(),
ring_buffer_free_read_page() must be called. For faster performance, this
page can be reused by the ring buffer to avoid having to free and allocate
new pages.
The issue arises when the page is used with a splice pipe into the
networking code. The networking code may up the page counter for the page,
and keep it active while sending it is queued to go to the network. The
incrementing of the page ref does not prevent it from being reused in the
ring buffer, and this can cause the page that is being sent out to the
network to be modified before it is sent by reading new data.
Add a check to the page ref counter, and only reuse the page if it is not
being used anywhere else.
Cc: stable@vger.kernel.org
Fixes: 73a757e631 ("ring-buffer: Return reader page back into existing ring buffer")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The ring_buffer_read_page() takes care of zeroing out any extra data in the
page that it returns. There's no need to zero it out again from the
consumer. It was removed from one consumer of this function, but
read_buffers_splice_read() did not remove it, and worse, it contained a
nasty bug because of it.
Cc: stable@vger.kernel.org
Fixes: 2711ca237a ("ring-buffer: Move zeroing out excess in page to ring buffer code")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Two info bits were added to the "commit" part of the ring buffer data page
when returned to be consumed. This was to inform the user space readers that
events have been missed, and that the count may be stored at the end of the
page.
What wasn't handled, was the splice code that actually called a function to
return the length of the data in order to zero out the rest of the page
before sending it up to user space. These data bits were returned with the
length making the value negative, and that negative value was not checked.
It was compared to PAGE_SIZE, and only used if the size was less than
PAGE_SIZE. Luckily PAGE_SIZE is unsigned long which made the compare an
unsigned compare, meaning the negative size value did not end up causing a
large portion of memory to be randomly zeroed out.
Cc: stable@vger.kernel.org
Fixes: 66a8cb95ed ("ring-buffer: Add place holder recording of dropped events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2017-12-18
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Allow arbitrary function calls from one BPF function to another BPF function.
As of today when writing BPF programs, __always_inline had to be used in
the BPF C programs for all functions, unnecessarily causing LLVM to inflate
code size. Handle this more naturally with support for BPF to BPF calls
such that this __always_inline restriction can be overcome. As a result,
it allows for better optimized code and finally enables to introduce core
BPF libraries in the future that can be reused out of different projects.
x86 and arm64 JIT support was added as well, from Alexei.
2) Add infrastructure for tagging functions as error injectable and allow for
BPF to return arbitrary error values when BPF is attached via kprobes on
those. This way of injecting errors generically eases testing and debugging
without having to recompile or restart the kernel. Tags for opting-in for
this facility are added with BPF_ALLOW_ERROR_INJECTION(), from Josef.
3) For BPF offload via nfp JIT, add support for bpf_xdp_adjust_head() helper
call for XDP programs. First part of this work adds handling of BPF
capabilities included in the firmware, and the later patches add support
to the nfp verifier part and JIT as well as some small optimizations,
from Jakub.
4) The bpftool now also gets support for basic cgroup BPF operations such
as attaching, detaching and listing current BPF programs. As a requirement
for the attach part, bpftool can now also load object files through
'bpftool prog load'. This reuses libbpf which we have in the kernel tree
as well. bpftool-cgroup man page is added along with it, from Roman.
5) Back then commit e87c6bc385 ("bpf: permit multiple bpf attachments for
a single perf event") added support for attaching multiple BPF programs
to a single perf event. Given they are configured through perf's ioctl()
interface, the interface has been extended with a PERF_EVENT_IOC_QUERY_BPF
command in this work in order to return an array of one or multiple BPF
prog ids that are currently attached, from Yonghong.
6) Various minor fixes and cleanups to the bpftool's Makefile as well
as a new 'uninstall' and 'doc-uninstall' target for removing bpftool
itself or prior installed documentation related to it, from Quentin.
7) Add CONFIG_CGROUP_BPF=y to the BPF kernel selftest config file which is
required for the test_dev_cgroup test case to run, from Naresh.
8) Fix reporting of XDP prog_flags for nfp driver, from Jakub.
9) Fix libbpf's exit code from the Makefile when libelf was not found in
the system, also from Jakub.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Things got moved around between the original bpf_override_return patches
and the final version, and now the ftrace kprobe dispatcher assumes if
you modified the ip that you also enabled preemption. Make a comment of
this and enable preemption, this fixes the lockdep splat that happened
when using this feature.
Fixes: 9802d86585 ("bpf: add a bpf_override_function helper")
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Pull networking fixes from David Miller:
1) Clamp timeouts to INT_MAX in conntrack, from Jay Elliot.
2) Fix broken UAPI for BPF_PROG_TYPE_PERF_EVENT, from Hendrik
Brueckner.
3) Fix locking in ieee80211_sta_tear_down_BA_sessions, from Johannes
Berg.
4) Add missing barriers to ptr_ring, from Michael S. Tsirkin.
5) Don't advertise gigabit in sh_eth when not available, from Thomas
Petazzoni.
6) Check network namespace when delivering to netlink taps, from Kevin
Cernekee.
7) Kill a race in raw_sendmsg(), from Mohamed Ghannam.
8) Use correct address in TCP md5 lookups when replying to an incoming
segment, from Christoph Paasch.
9) Add schedule points to BPF map alloc/free, from Eric Dumazet.
10) Don't allow silly mtu values to be used in ipv4/ipv6 multicast, also
from Eric Dumazet.
11) Fix SKB leak in tipc, from Jon Maloy.
12) Disable MAC learning on OVS ports of mlxsw, from Yuval Mintz.
13) SKB leak fix in skB_complete_tx_timestamp(), from Willem de Bruijn.
14) Add some new qmi_wwan device IDs, from Daniele Palmas.
15) Fix static key imbalance in ingress qdisc, from Jiri Pirko.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (76 commits)
net: qcom/emac: Reduce timeout for mdio read/write
net: sched: fix static key imbalance in case of ingress/clsact_init error
net: sched: fix clsact init error path
ip_gre: fix wrong return value of erspan_rcv
net: usb: qmi_wwan: add Telit ME910 PID 0x1101 support
pkt_sched: Remove TC_RED_OFFLOADED from uapi
net: sched: Move to new offload indication in RED
net: sched: Add TCA_HW_OFFLOAD
net: aquantia: Increment driver version
net: aquantia: Fix typo in ethtool statistics names
net: aquantia: Update hw counters on hw init
net: aquantia: Improve link state and statistics check interval callback
net: aquantia: Fill in multicast counter in ndev stats from hardware
net: aquantia: Fill ndev stat couters from hardware
net: aquantia: Extend stat counters to 64bit values
net: aquantia: Fix hardware DMA stream overload on large MRRS
net: aquantia: Fix actual speed capabilities reporting
sock: free skb in skb_complete_tx_timestamp on error
s390/qeth: update takeover IPs after configuration change
s390/qeth: lock IP table while applying takeover changes
...
- Comment fixes
- Build fix
- Better memory alloction (don't use NR_CPUS)
- Configuration fix
- Build warning fix
- Enhanced callback parameter (to simplify users of trace hooks)
- Give up on stack tracing when RCU isn't watching (it's a lost cause)
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Merge tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Various fix-ups:
- comment fixes
- build fix
- better memory alloction (don't use NR_CPUS)
- configuration fix
- build warning fix
- enhanced callback parameter (to simplify users of trace hooks)
- give up on stack tracing when RCU isn't watching (it's a lost
cause)"
* tag 'trace-v4.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Have stack trace not record if RCU is not watching
tracing: Pass export pointer as argument to ->write()
ring-buffer: Remove unused function __rb_data_page_index()
tracing: make PREEMPTIRQ_EVENTS depend on TRACING
tracing: Allocate mask_str buffer dynamically
tracing: always define trace_{irq,preempt}_{enable_disable}
tracing: Fix code comments in trace.c
The stack tracer records a stack dump whenever it sees a stack usage that is
more than what it ever saw before. This can happen at any function that is
being traced. If it happens when the CPU is going idle (or other strange
locations), RCU may not be watching, and in this case, the recording of the
stack trace will trigger a warning. There's been lots of efforts to make
hacks to allow stack tracing to proceed even if RCU is not watching, but
this only causes more issues to appear. Simply do not trace a stack if RCU
is not watching. It probably isn't a bad stack anyway.
Acked-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit f371b304f1 ("bpf/tracing: allow user space to
query prog array on the same tp") introduced a perf
ioctl command to query prog array attached to the
same perf tracepoint. The commit introduced a
compilation error under certain config conditions, e.g.,
(1). CONFIG_BPF_SYSCALL is not defined, or
(2). CONFIG_TRACING is defined but neither CONFIG_UPROBE_EVENTS
nor CONFIG_KPROBE_EVENTS is defined.
Error message:
kernel/events/core.o: In function `perf_ioctl':
core.c:(.text+0x98c4): undefined reference to `bpf_event_query_prog_array'
This patch fixed this error by guarding the real definition under
CONFIG_BPF_EVENTS and provided static inline dummy function
if CONFIG_BPF_EVENTS was not defined.
It renamed the function from bpf_event_query_prog_array to
perf_event_query_prog_array and moved the definition from linux/bpf.h
to linux/trace_events.h so the definition is in proximity to
other prog_array related functions.
Fixes: f371b304f1 ("bpf/tracing: allow user space to query prog array on the same tp")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
When tracing and networking programs are both attached in the
system and both use event-output helpers that eventually call
into perf_event_output(), then we could end up in a situation
where the tracing attached program runs in user context while
a cls_bpf program is triggered on that same CPU out of softirq
context.
Since both rely on the same per-cpu perf_sample_data, we could
potentially corrupt it. This can only ever happen in a combination
of the two types; all tracing programs use a bpf_prog_active
counter to bail out in case a program is already running on
that CPU out of a different context. XDP and cls_bpf programs
by themselves don't have this issue as they run in the same
context only. Therefore, split both perf_sample_data so they
cannot be accessed from each other.
Fixes: 20b9d7ac48 ("bpf: avoid excessive stack usage for perf_sample_data")
Reported-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Song Liu <songliubraving@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Error injection is sloppy and very ad-hoc. BPF could fill this niche
perfectly with it's kprobe functionality. We could make sure errors are
only triggered in specific call chains that we care about with very
specific situations. Accomplish this with the bpf_override_funciton
helper. This will modify the probe'd callers return value to the
specified value and set the PC to an override function that simply
returns, bypassing the originally probed function. This gives us a nice
clean way to implement systematic error injection for all of our code
paths.
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Commit e87c6bc385 ("bpf: permit multiple bpf attachments
for a single perf event") added support to attach multiple
bpf programs to a single perf event.
Although this provides flexibility, users may want to know
what other bpf programs attached to the same tp interface.
Besides getting visibility for the underlying bpf system,
such information may also help consolidate multiple bpf programs,
understand potential performance issues due to a large array,
and debug (e.g., one bpf program which overwrites return code
may impact subsequent program results).
Commit 2541517c32 ("tracing, perf: Implement BPF programs
attached to kprobes") utilized the existing perf ioctl
interface and added the command PERF_EVENT_IOC_SET_BPF
to attach a bpf program to a tracepoint. This patch adds a new
ioctl command, given a perf event fd, to query the bpf program
array attached to the same perf tracepoint event.
The new uapi ioctl command:
PERF_EVENT_IOC_QUERY_BPF
The new uapi/linux/perf_event.h structure:
struct perf_event_query_bpf {
__u32 ids_len;
__u32 prog_cnt;
__u32 ids[0];
};
User space provides buffer "ids" for kernel to copy to.
When returning from the kernel, the number of available
programs in the array is set in "prog_cnt".
The usage:
struct perf_event_query_bpf *query =
malloc(sizeof(*query) + sizeof(u32) * ids_len);
query.ids_len = ids_len;
err = ioctl(pmu_efd, PERF_EVENT_IOC_QUERY_BPF, query);
if (err == 0) {
/* query.prog_cnt is the number of available progs,
* number of progs in ids: (ids_len == 0) ? 0 : query.prog_cnt
*/
} else if (errno == ENOSPC) {
/* query.ids_len number of progs copied,
* query.prog_cnt is the number of available progs
*/
} else {
/* other errors */
}
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Pull networking fixes from David Miller:
1) Various TCP control block fixes, including one that crashes with
SELinux, from David Ahern and Eric Dumazet.
2) Fix ACK generation in rxrpc, from David Howells.
3) ipvlan doesn't set the mark properly in the ipv4 route lookup key,
from Gao Feng.
4) SIT configuration doesn't take on the frag_off ipv4 field
configuration properly, fix from Hangbin Liu.
5) TSO can fail after device down/up on stmmac, fix from Lars Persson.
6) Various bpftool fixes (mostly in JSON handling) from Quentin Monnet.
7) Various SKB leak fixes in vhost/tun/tap (mostly observed as
performance problems). From Wei Xu.
8) mvpps's TX descriptors were not zero initialized, from Yan Markman.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (57 commits)
tcp: use IPCB instead of TCP_SKB_CB in inet_exact_dif_match()
tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()
rxrpc: Fix the MAINTAINERS record
rxrpc: Use correct netns source in rxrpc_release_sock()
liquidio: fix incorrect indentation of assignment statement
stmmac: reset last TSO segment size after device open
ipvlan: Add the skb->mark as flow4's member to lookup route
s390/qeth: build max size GSO skbs on L2 devices
s390/qeth: fix GSO throughput regression
s390/qeth: fix thinko in IPv4 multicast address tracking
tap: free skb if flags error
tun: free skb in early errors
vhost: fix skb leak in handle_rx()
bnxt_en: Fix a variable scoping in bnxt_hwrm_do_send_msg()
bnxt_en: fix dst/src fid for vxlan encap/decap actions
bnxt_en: wildcard smac while creating tunnel decap filter
bnxt_en: Need to unconditionally shut down RoCE in bnxt_shutdown
phylink: ensure we take the link down when phylink_stop() is called
sfp: warn about modules requiring address change sequence
sfp: improve RX_LOS handling
...
Now that cond_resched() also provides RCU quiescent states when
needed, it can be used in place of cond_resched_rcu_qs(). This
commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
