The way we produce SBALs to the device (first update q->nr_buf_used,
then update the SLSB) should ensure that we never see some of the
SLSB states when scanning the queue for progress.
So make some noise if we do, this implies a bug in our SBAL tracking.
Also tweak the WARN msg to provide more information.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This removes the last remaining accesses to ->qdio_data from internal
code. Just pass the qdio_irq struct where needed instead.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
If we're unlucky with timing, we could be running task_work after
having dropped the memory context in the sq thread. Since dropping
the context requires a runnable task state, we cannot reliably drop
it as part of our check-for-work loop in io_sq_thread(). Instead,
abstract out the mm acquire for the sq thread into a helper, and call
it from the async task work handler.
Cc: stable@vger.kernel.org # v5.7
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In io_complete_rw_iopoll(), stores to io_kiocb's result and iopoll
completed are two independent store operations, to ensure that once
iopoll_completed is ture and then req->result must been perceived by
the cpu executing io_do_iopoll(), proper memory barrier should be used.
And in io_do_iopoll(), we check whether req->result is EAGAIN, if it is,
we'll need to issue this io request using io-wq again. In order to just
issue a single smp_rmb() on the completion side, move the re-submit work
to io_iopoll_complete().
Cc: stable@vger.kernel.org
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
[axboe: don't set ->iopoll_completed for -EAGAIN retry]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In IOPOLL mode, for EAGAIN error, we'll try to submit io request
again using io-wq, so don't fail rest of links if this io request
has links.
Cc: stable@vger.kernel.org
Signed-off-by: Xiaoguang Wang <xiaoguang.wang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- fixes for the SEV atomic pool (Geert Uytterhoeven and David Rientjes)
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Merge tag 'dma-mapping-5.8-3' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
"Fixes for the SEV atomic pool (Geert Uytterhoeven and David Rientjes)"
* tag 'dma-mapping-5.8-3' of git://git.infradead.org/users/hch/dma-mapping:
dma-pool: decouple DMA_REMAP from DMA_COHERENT_POOL
dma-pool: fix too large DMA pools on medium memory size systems
To pick the changes from:
b383a73f2b ("fs/ext4: Introduce DAX inode flag")
And silence this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/fs.h' differs from latest version at 'include/uapi/linux/fs.h'
diff -u tools/include/uapi/linux/fs.h include/uapi/linux/fs.h
It causes various beautifiers for things like fspick, fsmount, etc (see
below) to get rebuilt, but this specific change doesn't make 'perf
trace' be capable of decoding anything new, as we still don't decode
what comes from ioctls, just its cmds.
Details about the update:
$ cp include/uapi/linux/fs.h tools/include/uapi/linux/fs.h
$ git diff
diff --git a/tools/include/uapi/linux/fs.h b/tools/include/uapi/linux/fs.h
index 379a612f8f1d..f44eb0a04afd 100644
--- a/tools/include/uapi/linux/fs.h
+++ b/tools/include/uapi/linux/fs.h
@@ -262,6 +262,7 @@ struct fsxattr {
#define FS_EA_INODE_FL 0x00200000 /* Inode used for large EA */
#define FS_EOFBLOCKS_FL 0x00400000 /* Reserved for ext4 */
#define FS_NOCOW_FL 0x00800000 /* Do not cow file */
+#define FS_DAX_FL 0x02000000 /* Inode is DAX */
#define FS_INLINE_DATA_FL 0x10000000 /* Reserved for ext4 */
#define FS_PROJINHERIT_FL 0x20000000 /* Create with parents projid */
#define FS_CASEFOLD_FL 0x40000000 /* Folder is case insensitive */
$ m
make: Entering directory '/home/acme/git/perf/tools/perf'
BUILD: Doing 'make -j8' parallel build
INSTALL GTK UI
CC /tmp/build/perf/builtin-trace.o
DESCEND plugins
CC /tmp/build/perf/trace/beauty/fsmount.o
CC /tmp/build/perf/trace/beauty/fspick.o
CC /tmp/build/perf/trace/beauty/mount_flags.o
CC /tmp/build/perf/trace/beauty/move_mount.o
CC /tmp/build/perf/trace/beauty/renameat.o
CC /tmp/build/perf/trace/beauty/sync_file_range.o
INSTALL trace_plugins
LD /tmp/build/perf/trace/beauty/perf-in.o
LD /tmp/build/perf/perf-in.o
LINK /tmp/build/perf/perf
<SNIP>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To pick up the changes in:
7e5b3c267d ("x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation")
Addressing these tools/perf build warnings:
Warning: Kernel ABI header at 'tools/arch/x86/include/asm/msr-index.h' differs from latest version at 'arch/x86/include/asm/msr-index.h'
diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h
Warning: Kernel ABI header at 'tools/arch/x86/include/asm/cpufeatures.h' differs from latest version at 'arch/x86/include/asm/cpufeatures.h'
diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h
With this one will be able to use these new AMD MSRs in filters, by
name, e.g.:
# perf trace -e msr:* --filter "msr==IA32_MCU_OPT_CTRL"
^C#
Using -v we can see how it sets up the tracepoint filters, converting
from the string in the filter to the numeric value:
# perf trace -v -e msr:* --filter "msr==IA32_MCU_OPT_CTRL"
Using CPUID GenuineIntel-6-8E-A
0x123
New filter for msr:read_msr: (msr==0x123) && (common_pid != 335 && common_pid != 30344)
0x123
New filter for msr:write_msr: (msr==0x123) && (common_pid != 335 && common_pid != 30344)
0x123
New filter for msr:rdpmc: (msr==0x123) && (common_pid != 335 && common_pid != 30344)
mmap size 528384B
^C#
The updating process shows how this affects tooling in more detail:
$ diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h
--- tools/arch/x86/include/asm/msr-index.h 2020-06-03 10:36:09.959910238 -0300
+++ arch/x86/include/asm/msr-index.h 2020-06-17 10:04:20.235052901 -0300
@@ -128,6 +128,10 @@
#define TSX_CTRL_RTM_DISABLE BIT(0) /* Disable RTM feature */
#define TSX_CTRL_CPUID_CLEAR BIT(1) /* Disable TSX enumeration */
+/* SRBDS support */
+#define MSR_IA32_MCU_OPT_CTRL 0x00000123
+#define RNGDS_MITG_DIS BIT(0)
+
#define MSR_IA32_SYSENTER_CS 0x00000174
#define MSR_IA32_SYSENTER_ESP 0x00000175
#define MSR_IA32_SYSENTER_EIP 0x00000176
$ set -o vi
$ tools/perf/trace/beauty/tracepoints/x86_msr.sh > before
$ cp arch/x86/include/asm/msr-index.h tools/arch/x86/include/asm/msr-index.h
$ tools/perf/trace/beauty/tracepoints/x86_msr.sh > after
$ diff -u before after
--- before 2020-06-17 10:05:49.653114752 -0300
+++ after 2020-06-17 10:06:01.777258731 -0300
@@ -51,6 +51,7 @@
[0x0000011e] = "IA32_BBL_CR_CTL3",
[0x00000120] = "IDT_MCR_CTRL",
[0x00000122] = "IA32_TSX_CTRL",
+ [0x00000123] = "IA32_MCU_OPT_CTRL",
[0x00000140] = "MISC_FEATURES_ENABLES",
[0x00000174] = "IA32_SYSENTER_CS",
[0x00000175] = "IA32_SYSENTER_ESP",
$
The related change to cpu-features.h affects this:
CC /tmp/build/perf/bench/mem-memcpy-x86-64-asm.o
CC /tmp/build/perf/bench/mem-memset-x86-64-asm.o
This shouldn't be affecting that 'perf bench' entry:
$ find tools/perf/ -type f | xargs grep SRBDS
$
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Gross <mgross@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To get some newer headers that got out of sync with the copies in tools/
so that we can try to have the tools/perf/ build clean for v5.8 with
fewer pull requests.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixes segmentation fault when trying to interpret zstd-compressed data
with perf script:
```
$ perf record -z ls
...
[ perf record: Captured and wrote 0,010 MB perf.data, compressed (original 0,001 MB, ratio is 2,190) ]
$ memcheck perf script
...
==67911== Invalid read of size 4
==67911== at 0x5568188: ZSTD_decompressStream (in /usr/lib/libzstd.so.1.4.5)
==67911== by 0x6E726B: zstd_decompress_stream (zstd.c:100)
==67911== by 0x65729C: perf_session__process_compressed_event (session.c:72)
==67911== by 0x6598E8: perf_session__process_user_event (session.c:1583)
==67911== by 0x65BA59: reader__process_events (session.c:2177)
==67911== by 0x65BA59: __perf_session__process_events (session.c:2234)
==67911== by 0x65BA59: perf_session__process_events (session.c:2267)
==67911== by 0x5A7397: __cmd_script (builtin-script.c:2447)
==67911== by 0x5A7397: cmd_script (builtin-script.c:3840)
==67911== by 0x5FE9D2: run_builtin (perf.c:312)
==67911== by 0x711627: handle_internal_command (perf.c:364)
==67911== by 0x711627: run_argv (perf.c:408)
==67911== by 0x711627: main (perf.c:538)
==67911== Address 0x71d8 is not stack'd, malloc'd or (recently) free'd
```
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Acked-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
LPU-Reference: 20200612230333.72140-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Mostly for historical reasons, q->blk_trace is assigned through xchg()
and cmpxchg() atomic operations. Although this is correct, sparse
complains about this because it violates rcu annotations since commit
c780e86dd4 ("blktrace: Protect q->blk_trace with RCU") which started
to use rcu for accessing q->blk_trace. Furthermore there's no real need
for atomic operations anymore since all changes to q->blk_trace happen
under q->blk_trace_mutex and since it also makes more sense to check if
q->blk_trace is set with the mutex held earlier.
So let's just replace xchg() with rcu_replace_pointer() and cmpxchg()
with explicit check and rcu_assign_pointer(). This makes the code more
efficient and sparse happy.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
We use one blktrace per request_queue, that means one per the entire
disk. So we cannot run one blktrace on say /dev/vda and then /dev/vda1,
or just two calls on /dev/vda.
We check for concurrent setup only at the very end of the blktrace setup though.
If we try to run two concurrent blktraces on the same block device the
second one will fail, and the first one seems to go on. However when
one tries to kill the first one one will see things like this:
The kernel will show these:
```
debugfs: File 'dropped' in directory 'nvme1n1' already present!
debugfs: File 'msg' in directory 'nvme1n1' already present!
debugfs: File 'trace0' in directory 'nvme1n1' already present!
``
And userspace just sees this error message for the second call:
```
blktrace /dev/nvme1n1
BLKTRACESETUP(2) /dev/nvme1n1 failed: 5/Input/output error
```
The first userspace process #1 will also claim that the files
were taken underneath their nose as well. The files are taken
away form the first process given that when the second blktrace
fails, it will follow up with a BLKTRACESTOP and BLKTRACETEARDOWN.
This means that even if go-happy process #1 is waiting for blktrace
data, we *have* been asked to take teardown the blktrace.
This can easily be reproduced with break-blktrace [0] run_0005.sh test.
Just break out early if we know we're already going to fail, this will
prevent trying to create the files all over again, which we know still
exist.
[0] https://github.com/mcgrof/break-blktrace
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently the macro that inserts entries into the SPU syscall table
doesn't actually use the "nr" (syscall number) parameter.
This does work, but it relies on the exact right number of syscall
entries being emitted in order for the syscal numbers to line up with
the array entries. If for example we had two entries with the same
syscall number we wouldn't get an error, it would just cause all
subsequent syscalls to be off by one in the spu_syscall_table.
So instead change the macro to assign to the specific entry of the
array, meaning any numbering overlap will be caught by the compiler.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200616135617.2937252-1-mpe@ellerman.id.au
The pte_update() implementation for PPC_8xx unfolds page table from the PGD
level to access a PMD entry. Since 8xx has only 2-level page table this can
be simplified with pmd_off() shortcut.
Replace explicit unfolding with pmd_off() and drop defines of pgd_index()
and pgd_offset() that are no longer needed.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200615092229.23142-1-rppt@kernel.org
Unfortunately, most versions of clang that support BTI are capable of
miscompiling the kernel when converting a switch statement into a jump
table. As an example, attempting to spawn a KVM guest results in a panic:
[ 56.253312] Kernel panic - not syncing: bad mode
[ 56.253834] CPU: 0 PID: 279 Comm: lkvm Not tainted 5.8.0-rc1 #2
[ 56.254225] Hardware name: QEMU QEMU Virtual Machine, BIOS 0.0.0 02/06/2015
[ 56.254712] Call trace:
[ 56.254952] dump_backtrace+0x0/0x1d4
[ 56.255305] show_stack+0x1c/0x28
[ 56.255647] dump_stack+0xc4/0x128
[ 56.255905] panic+0x16c/0x35c
[ 56.256146] bad_el0_sync+0x0/0x58
[ 56.256403] el1_sync_handler+0xb4/0xe0
[ 56.256674] el1_sync+0x7c/0x100
[ 56.256928] kvm_vm_ioctl_check_extension_generic+0x74/0x98
[ 56.257286] __arm64_sys_ioctl+0x94/0xcc
[ 56.257569] el0_svc_common+0x9c/0x150
[ 56.257836] do_el0_svc+0x84/0x90
[ 56.258083] el0_sync_handler+0xf8/0x298
[ 56.258361] el0_sync+0x158/0x180
This is because the switch in kvm_vm_ioctl_check_extension_generic()
is executed as an indirect branch to tail-call through a jump table:
ffff800010032dc8: 3869694c ldrb w12, [x10, x9]
ffff800010032dcc: 8b0c096b add x11, x11, x12, lsl #2
ffff800010032dd0: d61f0160 br x11
However, where the target case uses the stack, the landing pad is elided
due to the presence of a paciasp instruction:
ffff800010032e14: d503233f paciasp
ffff800010032e18: a9bf7bfd stp x29, x30, [sp, #-16]!
ffff800010032e1c: 910003fd mov x29, sp
ffff800010032e20: aa0803e0 mov x0, x8
ffff800010032e24: 940017c0 bl ffff800010038d24 <kvm_vm_ioctl_check_extension>
ffff800010032e28: 93407c00 sxtw x0, w0
ffff800010032e2c: a8c17bfd ldp x29, x30, [sp], #16
ffff800010032e30: d50323bf autiasp
ffff800010032e34: d65f03c0 ret
Unfortunately, this results in a fatal exception because paciasp is
compatible only with branch-and-link (call) instructions and not simple
indirect branches.
A fix is being merged into Clang 10.0.1 so that a 'bti j' instruction is
emitted as an explicit landing pad in this situation. Make in-kernel
BTI depend on that compiler version when building with clang.
Cc: Tom Stellard <tstellar@redhat.com>
Cc: Daniel Kiss <daniel.kiss@arm.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20200615105524.GA2694@willie-the-truck
Link: https://lore.kernel.org/r/20200616183630.2445-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
Compared to its predecessors, the PX30 VOP has a different register layout
for enabling per-pixel alpha. Instead of src_alpha_ctl and dst_alpha_ctl,
there is a single alpha control register. This register takes some fields
from src_alpha_ctl, but with a different layout.
Add support for the required fields to the PX30 VOP window descriptions,
which makes per-pixel-alpha formats behave correctly.
Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20200416140526.262533-1-paul.kocialkowski@bootlin.com
Add flex_array_size() helper for the calculation of the size, in bytes,
of a flexible array member contained within an enclosing structure.
Example of usage:
struct something {
size_t count;
struct foo items[];
};
struct something *instance;
instance = kmalloc(struct_size(instance, items, count), GFP_KERNEL);
instance->count = count;
memcpy(instance->items, src, flex_array_size(instance, items, instance->count));
The helper returns SIZE_MAX on overflow instead of wrapping around.
Additionally replaces parameter "n" with "count" in struct_size() helper
for greater clarity and unification.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200609012233.GA3371@embeddedor
Signed-off-by: Kees Cook <keescook@chromium.org>
cc-option and as-option are almost the same; both pass the flag to
$(CC). The main difference is the cc-option stops before the assemble
stage (-S option) whereas as-option stops after (-c option).
I chose -S because it is slightly faster, but $(cc-option,-gz=zlib)
returns a wrong result (https://lkml.org/lkml/2020/6/9/1529).
It has been fixed by commit 7b16994437 ("Makefile: Improve compressed
debug info support detection"), but the assembler should always be
invoked for more reliable compiler option tests.
However, you cannot simply replace -S with -c because the following
code in lib/Kconfig.debug would break:
depends on $(cc-option,-gsplit-dwarf)
The combination of -c and -gsplit-dwarf does not accept /dev/null as
output.
$ cat /dev/null | gcc -gsplit-dwarf -S -x c - -o /dev/null
$ echo $?
0
$ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o /dev/null
objcopy: Warning: '/dev/null' is not an ordinary file
$ echo $?
1
$ cat /dev/null | gcc -gsplit-dwarf -c -x c - -o tmp.o
$ echo $?
0
There is another flag that creates an separate file based on the
object file path:
$ cat /dev/null | gcc -ftest-coverage -c -x c - -o /dev/null
<stdin>:1: error: cannot open /dev/null.gcno
So, we cannot use /dev/null to sink the output.
Align the cc-option implementation with scripts/Kbuild.include.
With -c option used in cc-option, as-option is unneeded.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Add testcases for the return value of the command to show
bootconfig in initrd, and double/single quotes selecting.
Link: http://lkml.kernel.org/r/159230247428.65555.2109472942519215104.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix bootconfig to return 0 if succeeded to show the bootconfig
in initrd. Without this fix, "bootconfig INITRD" command
returns !0 even if the command succeeded to show the bootconfig.
Link: http://lkml.kernel.org/r/159230246566.65555.11891772258543514487.stgit@devnote2
Cc: stable@vger.kernel.org
Fixes: 950313ebf7 ("tools: bootconfig: Add bootconfig command")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix bootconfig tool to select double or single quotes
correctly according to the value.
If a bootconfig value includes a double quote character,
we must use single-quotes to quote that value.
Link: http://lkml.kernel.org/r/159230245697.65555.12444299015852932304.stgit@devnote2
Cc: stable@vger.kernel.org
Fixes: 950313ebf7 ("tools: bootconfig: Add bootconfig command")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix /proc/bootconfig to select double or single quotes
corrctly according to the value.
If a bootconfig value includes a double quote character,
we must use single-quotes to quote that value.
This modifies if() condition and blocks for avoiding
double-quote in value check in 2 places. Anyway, since
xbc_array_for_each_value() can handle the array which
has a single node correctly.
Thus,
if (vnode && xbc_node_is_array(vnode)) {
xbc_array_for_each_value(vnode) /* vnode->next != NULL */
...
} else {
snprintf(val); /* val is an empty string if !vnode */
}
is equivalent to
if (vnode) {
xbc_array_for_each_value(vnode) /* vnode->next can be NULL */
...
} else {
snprintf(""); /* value is always empty */
}
Link: http://lkml.kernel.org/r/159230244786.65555.3763894451251622488.stgit@devnote2
Cc: stable@vger.kernel.org
Fixes: c1a3c36017 ("proc: bootconfig: Add /proc/bootconfig to show boot config list")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
We do not use the event variable, just remove it.
Signed-off-by: YangHui <yanghui.def@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
kmemleak report:
[<57dcc2ca>] __kmalloc_track_caller+0x139/0x2b0
[<f1c45d0f>] kstrndup+0x37/0x80
[<f9761eb0>] parse_probe_arg.isra.7+0x3cc/0x630
[<055bf2ba>] traceprobe_parse_probe_arg+0x2f5/0x810
[<655a7766>] trace_kprobe_create+0x2ca/0x950
[<4fc6a02a>] create_or_delete_trace_kprobe+0xf/0x30
[<6d1c8a52>] trace_run_command+0x67/0x80
[<be812cc0>] trace_parse_run_command+0xa7/0x140
[<aecfe401>] probes_write+0x10/0x20
[<2027641c>] __vfs_write+0x30/0x1e0
[<6a4aeee1>] vfs_write+0x96/0x1b0
[<3517fb7d>] ksys_write+0x53/0xc0
[<dad91db7>] __ia32_sys_write+0x15/0x20
[<da347f64>] do_syscall_32_irqs_on+0x3d/0x260
[<fd0b7e7d>] do_fast_syscall_32+0x39/0xb0
[<ea5ae810>] entry_SYSENTER_32+0xaf/0x102
Post parse_probe_arg(), the FETCH_OP_DATA operation type is overwritten
to FETCH_OP_ST_STRING, as a result memory is never freed since
traceprobe_free_probe_arg() iterates only over SYMBOL and DATA op types
Setup fetch string operation correctly after fetch_op_data operation.
Link: https://lkml.kernel.org/r/20200615143034.GA1734@cosmos
Cc: stable@vger.kernel.org
Fixes: a42e3c4de9 ("tracing/probe: Add immediate string parameter support")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When using trace-cmd on 5.6-rt for the function graph tracer, the output was
corrupted. It gave output like this:
funcgraph_entry: func=0xffffffff depth=38982
funcgraph_entry: func=0x1ffffffff depth=16044
funcgraph_exit: func=0xffffffff overrun=0x92539aaf00000000 calltime=0x92539c9900000072 rettime=0x100000072 depth=11084
funcgraph_exit: func=0xffffffff overrun=0x9253946e00000000 calltime=0x92539e2100000072 rettime=0x72 depth=26033702
funcgraph_entry: func=0xffffffff depth=85798
funcgraph_entry: func=0x1ffffffff depth=12044
The reason was because the tracefs/events/ftrace/funcgraph_entry/exit format
file was incorrect. The -rt kernel adds more common fields to the trace
events. Namely, common_migrate_disable and common_preempt_lazy_count. Each
is one byte in size. This changes the alignment of the normal payload. Most
events are aligned normally, but the function and function graph events are
defined with a "PACKED" macro, that packs their payload. As the offsets
displayed in the format files are now calculated by an aligned field, the
aligned field for function and function graph events should be 1, not their
normal alignment.
With aligning of the funcgraph_entry event, the format file has:
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:unsigned char common_migrate_disable; offset:8; size:1; signed:0;
field:unsigned char common_preempt_lazy_count; offset:9; size:1; signed:0;
field:unsigned long func; offset:16; size:8; signed:0;
field:int depth; offset:24; size:4; signed:1;
But the actual alignment is:
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:unsigned char common_migrate_disable; offset:8; size:1; signed:0;
field:unsigned char common_preempt_lazy_count; offset:9; size:1; signed:0;
field:unsigned long func; offset:12; size:8; signed:0;
field:int depth; offset:20; size:4; signed:1;
Link: https://lkml.kernel.org/r/20200609220041.2a3b527f@oasis.local.home
Cc: stable@vger.kernel.org
Fixes: 04ae87a520 ("ftrace: Rework event_create_dir()")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Ziqian reported lockup when adding retprobe on _raw_spin_lock_irqsave.
My test was also able to trigger lockdep output:
============================================
WARNING: possible recursive locking detected
5.6.0-rc6+ #6 Not tainted
--------------------------------------------
sched-messaging/2767 is trying to acquire lock:
ffffffff9a492798 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_hash_lock+0x52/0xa0
but task is already holding lock:
ffffffff9a491a18 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_trampoline+0x0/0x50
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(&(kretprobe_table_locks[i].lock));
lock(&(kretprobe_table_locks[i].lock));
*** DEADLOCK ***
May be due to missing lock nesting notation
1 lock held by sched-messaging/2767:
#0: ffffffff9a491a18 (&(kretprobe_table_locks[i].lock)){-.-.}, at: kretprobe_trampoline+0x0/0x50
stack backtrace:
CPU: 3 PID: 2767 Comm: sched-messaging Not tainted 5.6.0-rc6+ #6
Call Trace:
dump_stack+0x96/0xe0
__lock_acquire.cold.57+0x173/0x2b7
? native_queued_spin_lock_slowpath+0x42b/0x9e0
? lockdep_hardirqs_on+0x590/0x590
? __lock_acquire+0xf63/0x4030
lock_acquire+0x15a/0x3d0
? kretprobe_hash_lock+0x52/0xa0
_raw_spin_lock_irqsave+0x36/0x70
? kretprobe_hash_lock+0x52/0xa0
kretprobe_hash_lock+0x52/0xa0
trampoline_handler+0xf8/0x940
? kprobe_fault_handler+0x380/0x380
? find_held_lock+0x3a/0x1c0
kretprobe_trampoline+0x25/0x50
? lock_acquired+0x392/0xbc0
? _raw_spin_lock_irqsave+0x50/0x70
? __get_valid_kprobe+0x1f0/0x1f0
? _raw_spin_unlock_irqrestore+0x3b/0x40
? finish_task_switch+0x4b9/0x6d0
? __switch_to_asm+0x34/0x70
? __switch_to_asm+0x40/0x70
The code within the kretprobe handler checks for probe reentrancy,
so we won't trigger any _raw_spin_lock_irqsave probe in there.
The problem is in outside kprobe_flush_task, where we call:
kprobe_flush_task
kretprobe_table_lock
raw_spin_lock_irqsave
_raw_spin_lock_irqsave
where _raw_spin_lock_irqsave triggers the kretprobe and installs
kretprobe_trampoline handler on _raw_spin_lock_irqsave return.
The kretprobe_trampoline handler is then executed with already
locked kretprobe_table_locks, and first thing it does is to
lock kretprobe_table_locks ;-) the whole lockup path like:
kprobe_flush_task
kretprobe_table_lock
raw_spin_lock_irqsave
_raw_spin_lock_irqsave ---> probe triggered, kretprobe_trampoline installed
---> kretprobe_table_locks locked
kretprobe_trampoline
trampoline_handler
kretprobe_hash_lock(current, &head, &flags); <--- deadlock
Adding kprobe_busy_begin/end helpers that mark code with fake
probe installed to prevent triggering of another kprobe within
this code.
Using these helpers in kprobe_flush_task, so the probe recursion
protection check is hit and the probe is never set to prevent
above lockup.
Link: http://lkml.kernel.org/r/158927059835.27680.7011202830041561604.stgit@devnote2
Fixes: ef53d9c5e4 ("kprobes: improve kretprobe scalability with hashed locking")
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Gustavo A . R . Silva" <gustavoars@kernel.org>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Reported-by: "Ziqian SUN (Zamir)" <zsun@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix to remove redundant arch_disarm_kprobe() call in
force_unoptimize_kprobe(). This arch_disarm_kprobe()
will be invoked if the kprobe is optimized but disabled,
but that means the kprobe (optprobe) is unused (and
unoptimized) state.
In that case, unoptimize_kprobe() puts it in freeing_list
and kprobe_optimizer (do_unoptimize_kprobes()) automatically
disarm it. Thus this arch_disarm_kprobe() is redundant.
Link: http://lkml.kernel.org/r/158927058719.27680.17183632908465341189.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In kprobe_optimizer() kick_kprobe_optimizer() is called
without kprobe_mutex, but this can race with other caller
which is protected by kprobe_mutex.
To fix that, expand kprobe_mutex protected area to protect
kick_kprobe_optimizer() call.
Link: http://lkml.kernel.org/r/158927057586.27680.5036330063955940456.stgit@devnote2
Fixes: cd7ebe2298 ("kprobes: Use text_poke_smp_batch for optimizing")
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Gustavo A . R . Silva" <gustavoars@kernel.org>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ziqian SUN <zsun@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Current kprobes uses RCU traversal APIs on kprobe_tables
even if it is safe because kprobe_mutex is locked.
Make those traversals to non-RCU APIs where the kprobe_mutex
is locked.
Link: http://lkml.kernel.org/r/158927056452.27680.9710575332163005121.stgit@devnote2
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Anders reported that the lockdep warns that suspicious
RCU list usage in register_kprobe() (detected by
CONFIG_PROVE_RCU_LIST.) This is because get_kprobe()
access kprobe_table[] by hlist_for_each_entry_rcu()
without rcu_read_lock.
If we call get_kprobe() from the breakpoint handler context,
it is run with preempt disabled, so this is not a problem.
But in other cases, instead of rcu_read_lock(), we locks
kprobe_mutex so that the kprobe_table[] is not updated.
So, current code is safe, but still not good from the view
point of RCU.
Joel suggested that we can silent that warning by passing
lockdep_is_held() to the last argument of
hlist_for_each_entry_rcu().
Add lockdep_is_held(&kprobe_mutex) at the end of the
hlist_for_each_entry_rcu() to suppress the warning.
Link: http://lkml.kernel.org/r/158927055350.27680.10261450713467997503.stgit@devnote2
Reported-by: Anders Roxell <anders.roxell@linaro.org>
Suggested-by: Joel Fernandes <joel@joelfernandes.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When cc-option and friends evaluate compiler flags, the temporary file
$$TMP is created as an output object, and automatically cleaned up.
The actual file path of $$TMP is .<pid>.tmp, here <pid> is the process
ID of $(shell ...) invoked from cc-option. (Please note $$$$ is the
escape sequence of $$).
Such garbage files are cleaned up in most cases, but some compiler flags
create additional output files.
For example, -gsplit-dwarf creates a .dwo file.
When CONFIG_DEBUG_INFO_SPLIT=y, you will see a bunch of .<pid>.dwo files
left in the top of build directories. You may not notice them unless you
do 'ls -a', but the garbage files will increase every time you run 'make'.
This commit changes the temporary object path to .tmp_<pid>/tmp, and
removes .tmp_<pid> directory when exiting. Separate build artifacts such
as *.dwo will be cleaned up all together because their file paths are
usually determined based on the base name of the object.
Another example is -ftest-coverage, which outputs the coverage data into
<base-name-of-object>.gcno
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Like live_unlite_ring, but instead of simply looking at the impact of
intel_ring_direction(), check that preemption more generally works with
different depths of queued requests in the ring.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200616233733.18050-1-chris@chris-wilson.co.uk
Pull networking fixes from David Miller:
1) Don't get per-cpu pointer with preemption enabled in nft_set_pipapo,
fix from Stefano Brivio.
2) Fix memory leak in ctnetlink, from Pablo Neira Ayuso.
3) Multiple definitions of MPTCP_PM_MAX_ADDR, from Geliang Tang.
4) Accidently disabling NAPI in non-error paths of macb_open(), from
Charles Keepax.
5) Fix races between alx_stop and alx_remove, from Zekun Shen.
6) We forget to re-enable SRIOV during resume in bnxt_en driver, from
Michael Chan.
7) Fix memory leak in ipv6_mc_destroy_dev(), from Wang Hai.
8) rxtx stats use wrong index in mvpp2 driver, from Sven Auhagen.
9) Fix memory leak in mptcp_subflow_create_socket error path, from Wei
Yongjun.
10) We should not adjust the TCP window advertised when sending dup acks
in non-SACK mode, because it won't be counted as a dup by the sender
if the window size changes. From Eric Dumazet.
11) Destroy the right number of queues during remove in mvpp2 driver,
from Sven Auhagen.
12) Various WOL and PM fixes to e1000 driver, from Chen Yu, Vaibhav
Gupta, and Arnd Bergmann.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (35 commits)
e1000e: fix unused-function warning
e1000: use generic power management
e1000e: Do not wake up the system via WOL if device wakeup is disabled
lan743x: add MODULE_DEVICE_TABLE for module loading alias
mlxsw: spectrum: Adjust headroom buffers for 8x ports
bareudp: Fixed configuration to avoid having garbage values
mvpp2: remove module bugfix
tcp: grow window for OOO packets only for SACK flows
mptcp: fix memory leak in mptcp_subflow_create_socket()
netfilter: flowtable: Make nf_flow_table_offload_add/del_cb inline
net/sched: act_ct: Make tcf_ct_flow_table_restore_skb inline
net: dsa: sja1105: fix PTP timestamping with large tc-taprio cycles
mvpp2: ethtool rxtx stats fix
MAINTAINERS: switch to my private email for Renesas Ethernet drivers
rocker: fix incorrect error handling in dma_rings_init
test_objagg: Fix potential memory leak in error handling
net: ethernet: mtk-star-emac: simplify interrupt handling
mld: fix memory leak in ipv6_mc_destroy_dev()
bnxt_en: Return from timer if interface is not in open state.
bnxt_en: Fix AER reset logic on 57500 chips.
...
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Merge tag 'afs-fixes-20200616' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS fixes from David Howells:
"I've managed to get xfstests kind of working with afs. Here are a set
of patches that fix most of the bugs found.
There are a number of primary issues:
- Incorrect handling of mtime and non-handling of ctime. It might be
argued, that the latter isn't a bug since the AFS protocol doesn't
support ctime, but I should probably still update it locally.
- Shared-write mmap, truncate and writeback bugs. This includes not
changing i_size under the callback lock, overwriting local i_size
with the reply from the server after a partial writeback, not
limiting the writeback from an mmapped page to EOF.
- Checks for an abort code indicating that the primary vnode in an
operation was deleted by a third-party are done in the wrong place.
- Silly rename bugs. This includes an incomplete conversion to the
new operation handling, duplicate nlink handling, nlink changing
not being done inside the callback lock and insufficient handling
of third-party conflicting directory changes.
And some secondary ones:
- The UAEOVERFLOW abort code should map to EOVERFLOW not EREMOTEIO.
- Remove a couple of unused or incompletely used bits.
- Remove a couple of redundant success checks.
These seem to fix all the data-corruption bugs found by
./check -afs -g quick
along with the obvious silly rename bugs and time bugs.
There are still some test failures, but they seem to fall into two
classes: firstly, the authentication/security model is different to
the standard UNIX model and permission is arbitrated by the server and
cached locally; and secondly, there are a number of features that AFS
does not support (such as mknod). But in these cases, the tests
themselves need to be adapted or skipped.
Using the in-kernel afs client with xfstests also found a bug in the
AuriStor AFS server that has been fixed for a future release"
* tag 'afs-fixes-20200616' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Fix silly rename
afs: afs_vnode_commit_status() doesn't need to check the RPC error
afs: Fix use of afs_check_for_remote_deletion()
afs: Remove afs_operation::abort_code
afs: Fix yfs_fs_fetch_status() to honour vnode selector
afs: Remove yfs_fs_fetch_file_status() as it's not used
afs: Fix the mapping of the UAEOVERFLOW abort code
afs: Fix truncation issues and mmap writeback size
afs: Concoct ctimes
afs: Fix EOF corruption
afs: afs_write_end() should change i_size under the right lock
afs: Fix non-setting of mtime when writing into mmap
Clang static analysis reports this double free error
security/selinux/ss/conditional.c:139:2: warning: Attempt to free released memory [unix.Malloc]
kfree(node->expr.nodes);
^~~~~~~~~~~~~~~~~~~~~~~
When cond_read_node fails, it calls cond_node_destroy which frees the
node but does not poison the entry in the node list. So when it
returns to its caller cond_read_list, cond_read_list deletes the
partial list. The latest entry in the list will be deleted twice.
So instead of freeing the node in cond_read_node, let list freeing in
code_read_list handle the freeing the problem node along with all of the
earlier nodes.
Because cond_read_node no longer does any error handling, the goto's
the error case are redundant. Instead just return the error code.
Cc: stable@vger.kernel.org
Fixes: 60abd3181d ("selinux: convert cond_list to array")
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Ondrej Mosnacek <omosnace@redhat.com>
[PM: subject line tweaks]
Signed-off-by: Paul Moore <paul@paul-moore.com>
Hi Linus,
Please, pull the following patches that replace zero-length arrays with
flexible-array members.
Notice that all of these patches have been baking in linux-next for
two development cycles now.
There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].
C99 introduced “flexible array members”, which lacks a numeric size for the
array declaration entirely:
struct something {
size_t count;
struct foo items[];
};
This is the way the kernel expects dynamically sized trailing elements to be
declared. It allows the compiler to generate errors when the flexible array
does not occur last in the structure, which helps to prevent some kind of
undefined behavior[3] bugs from being inadvertently introduced to the codebase.
It also allows the compiler to correctly analyze array sizes (via sizeof(),
CONFIG_FORTIFY_SOURCE, and CONFIG_UBSAN_BOUNDS). For instance, there is no
mechanism that warns us that the following application of the sizeof() operator
to a zero-length array always results in zero:
struct something {
size_t count;
struct foo items[0];
};
struct something *instance;
instance = kmalloc(struct_size(instance, items, count), GFP_KERNEL);
instance->count = count;
size = sizeof(instance->items) * instance->count;
memcpy(instance->items, source, size);
At the last line of code above, size turns out to be zero, when one might have
thought it represents the total size in bytes of the dynamic memory recently
allocated for the trailing array items. Here are a couple examples of this
issue[4][5]. Instead, flexible array members have incomplete type, and so the
sizeof() operator may not be applied[6], so any misuse of such operators will
be immediately noticed at build time.
The cleanest and least error-prone way to implement this is through the use of
a flexible array member:
struct something {
size_t count;
struct foo items[];
};
struct something *instance;
instance = kmalloc(struct_size(instance, items, count), GFP_KERNEL);
instance->count = count;
size = sizeof(instance->items[0]) * instance->count;
memcpy(instance->items, source, size);
Thanks
--
Gustavo
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21
[3] https://git.kernel.org/linus/76497732932f15e7323dc805e8ea8dc11bb587cf
[4] https://git.kernel.org/linus/f2cd32a443da694ac4e28fbf4ac6f9d5cc63a539
[5] https://git.kernel.org/linus/ab91c2a89f86be2898cee208d492816ec238b2cf
[6] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
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Merge tag 'flex-array-conversions-5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux
Pull flexible-array member conversions from Gustavo A. R. Silva:
"Replace zero-length arrays with flexible-array members.
Notice that all of these patches have been baking in linux-next for
two development cycles now.
There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should no
longer be used[2].
C99 introduced “flexible array members”, which lacks a numeric size
for the array declaration entirely:
struct something {
size_t count;
struct foo items[];
};
This is the way the kernel expects dynamically sized trailing elements
to be declared. It allows the compiler to generate errors when the
flexible array does not occur last in the structure, which helps to
prevent some kind of undefined behavior[3] bugs from being
inadvertently introduced to the codebase.
It also allows the compiler to correctly analyze array sizes (via
sizeof(), CONFIG_FORTIFY_SOURCE, and CONFIG_UBSAN_BOUNDS). For
instance, there is no mechanism that warns us that the following
application of the sizeof() operator to a zero-length array always
results in zero:
struct something {
size_t count;
struct foo items[0];
};
struct something *instance;
instance = kmalloc(struct_size(instance, items, count), GFP_KERNEL);
instance->count = count;
size = sizeof(instance->items) * instance->count;
memcpy(instance->items, source, size);
At the last line of code above, size turns out to be zero, when one
might have thought it represents the total size in bytes of the
dynamic memory recently allocated for the trailing array items. Here
are a couple examples of this issue[4][5].
Instead, flexible array members have incomplete type, and so the
sizeof() operator may not be applied[6], so any misuse of such
operators will be immediately noticed at build time.
The cleanest and least error-prone way to implement this is through
the use of a flexible array member:
struct something {
size_t count;
struct foo items[];
};
struct something *instance;
instance = kmalloc(struct_size(instance, items, count), GFP_KERNEL);
instance->count = count;
size = sizeof(instance->items[0]) * instance->count;
memcpy(instance->items, source, size);
instead"
[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
[4] commit f2cd32a443 ("rndis_wlan: Remove logically dead code")
[5] commit ab91c2a89f ("tpm: eventlog: Replace zero-length array with flexible-array member")
[6] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
* tag 'flex-array-conversions-5.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (41 commits)
w1: Replace zero-length array with flexible-array
tracing/probe: Replace zero-length array with flexible-array
soc: ti: Replace zero-length array with flexible-array
tifm: Replace zero-length array with flexible-array
dmaengine: tegra-apb: Replace zero-length array with flexible-array
stm class: Replace zero-length array with flexible-array
Squashfs: Replace zero-length array with flexible-array
ASoC: SOF: Replace zero-length array with flexible-array
ima: Replace zero-length array with flexible-array
sctp: Replace zero-length array with flexible-array
phy: samsung: Replace zero-length array with flexible-array
RxRPC: Replace zero-length array with flexible-array
rapidio: Replace zero-length array with flexible-array
media: pwc: Replace zero-length array with flexible-array
firmware: pcdp: Replace zero-length array with flexible-array
oprofile: Replace zero-length array with flexible-array
block: Replace zero-length array with flexible-array
tools/testing/nvdimm: Replace zero-length array with flexible-array
libata: Replace zero-length array with flexible-array
kprobes: Replace zero-length array with flexible-array
...
The purgatory Makefile removes -fstack-protector options if they were
configured in, but does not currently add -fno-stack-protector.
If gcc was configured with the --enable-default-ssp configure option,
this results in the stack protector still being enabled for the
purgatory (absent distro-specific specs files that might disable it
again for freestanding compilations), if the main kernel is being
compiled with stack protection enabled (if it's disabled for the main
kernel, the top-level Makefile will add -fno-stack-protector).
This will break the build since commit
e4160b2e4b ("x86/purgatory: Fail the build if purgatory.ro has missing symbols")
and prior to that would have caused runtime failure when trying to use
kexec.
Explicitly add -fno-stack-protector to avoid this, as done in other
Makefiles that need to disable the stack protector.
Reported-by: Gabriel C <nix.or.die@googlemail.com>
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Not too long ago, we realised we had issues with a rolling back a
context so far for a preemption request we considered the resubmit not
to be a rollback but a forward roll. This means we would issue a lite
restore instead of forcing a full restore, continuing execution of the
old requests rather than causing a preemption. Add a selftest to
exercise such a far rollback, such that if we were to skip the full
restore, we would execute invalid instructions in the ring and hang.
Note that while I was able to confirm that this causes us to do a
lite-restore preemption rollback (with commit e36ba817fa ("drm/i915/gt:
Incrementally check for rewinding") disabled), it did not trick the HW
into rolling past the old RING_TAIL. Myybe on other HW.
References: e36ba817fa ("drm/i915/gt: Incrementally check for rewinding")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200616185518.11948-1-chris@chris-wilson.co.uk
Jeff Kirsher says:
====================
Intel Wired LAN Driver Updates 2020-06-16
This series contains fixes to e1000 and e1000e.
Chen fixes an e1000e issue where systems could be waken via WoL, even
though the user has disabled the wakeup bit via sysfs.
Vaibhav Gupta updates the e1000 driver to clean up the legacy Power
Management hooks.
Arnd Bergmann cleans up the inconsistent use CONFIG_PM_SLEEP
preprocessor tags, which also resolves the compiler warnings about the
possibility of unused structure.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
