Commit Graph

27349 Commits

Author SHA1 Message Date
Björn Töpel
fbfc504a24 bpf: introduce new bpf AF_XDP map type BPF_MAP_TYPE_XSKMAP
The xskmap is yet another BPF map, very much inspired by
dev/cpu/sockmap, and is a holder of AF_XDP sockets. A user application
adds AF_XDP sockets into the map, and by using the bpf_redirect_map
helper, an XDP program can redirect XDP frames to an AF_XDP socket.

Note that a socket that is bound to certain ifindex/queue index will
*only* accept XDP frames from that netdev/queue index. If an XDP
program tries to redirect from a netdev/queue index other than what
the socket is bound to, the frame will not be received on the socket.

A socket can reside in multiple maps.

v3: Fixed race and simplified code.
v2: Removed one indirection in map lookup.

Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-05-03 15:55:24 -07:00
Alexei Starovoitov
4d220ed0f8 bpf: remove tracepoints from bpf core
tracepoints to bpf core were added as a way to provide introspection
to bpf programs and maps, but after some time it became clear that
this approach is inadequate, so prog_id, map_id and corresponding
get_next_id, get_fd_by_id, get_info_by_fd, prog_query APIs were
introduced and fully adopted by bpftool and other applications.
The tracepoints in bpf core started to rot and causing syzbot warnings:
WARNING: CPU: 0 PID: 3008 at kernel/trace/trace_event_perf.c:274
Kernel panic - not syncing: panic_on_warn set ...
perf_trace_bpf_map_keyval+0x260/0xbd0 include/trace/events/bpf.h:228
trace_bpf_map_update_elem include/trace/events/bpf.h:274 [inline]
map_update_elem kernel/bpf/syscall.c:597 [inline]
SYSC_bpf kernel/bpf/syscall.c:1478 [inline]
Hence this patch deletes tracepoints in bpf core.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Reported-by: syzbot <bot+a9dbb3c3e64b62536a4bc5ee7bbd4ca627566188@syzkaller.appspotmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-30 10:55:56 +02:00
Teng Qin
7ef3771205 bpf: Allow bpf_current_task_under_cgroup in interrupt
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>
2018-04-29 09:18:04 -07:00
Yonghong Song
9cbe1f5a32 bpf/verifier: improve register value range tracking with ARSH
When helpers like bpf_get_stack returns an int value
and later on used for arithmetic computation, the LSH and ARSH
operations are often required to get proper sign extension into
64-bit. For example, without this patch:
    54: R0=inv(id=0,umax_value=800)
    54: (bf) r8 = r0
    55: R0=inv(id=0,umax_value=800) R8_w=inv(id=0,umax_value=800)
    55: (67) r8 <<= 32
    56: R8_w=inv(id=0,umax_value=3435973836800,var_off=(0x0; 0x3ff00000000))
    56: (c7) r8 s>>= 32
    57: R8=inv(id=0)
With this patch:
    54: R0=inv(id=0,umax_value=800)
    54: (bf) r8 = r0
    55: R0=inv(id=0,umax_value=800) R8_w=inv(id=0,umax_value=800)
    55: (67) r8 <<= 32
    56: R8_w=inv(id=0,umax_value=3435973836800,var_off=(0x0; 0x3ff00000000))
    56: (c7) r8 s>>= 32
    57: R8=inv(id=0, umax_value=800,var_off=(0x0; 0x3ff))
With better range of "R8", later on when "R8" is added to other register,
e.g., a map pointer or scalar-value register, the better register
range can be derived and verifier failure may be avoided.

In our later example,
    ......
    usize = bpf_get_stack(ctx, raw_data, max_len, BPF_F_USER_STACK);
    if (usize < 0)
        return 0;
    ksize = bpf_get_stack(ctx, raw_data + usize, max_len - usize, 0);
    ......
Without improving ARSH value range tracking, the register representing
"max_len - usize" will have smin_value equal to S64_MIN and will be
rejected by verifier.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:53 -07:00
Yonghong Song
afbe1a5b79 bpf: remove never-hit branches in verifier adjust_scalar_min_max_vals
In verifier function adjust_scalar_min_max_vals,
when src_known is false and the opcode is BPF_LSH/BPF_RSH,
early return will happen in the function. So remove
the branch in handling BPF_LSH/BPF_RSH when src_known is false.

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:53 -07:00
Yonghong Song
849fa50662 bpf/verifier: refine retval R0 state for bpf_get_stack helper
The special property of return values for helpers bpf_get_stack
and bpf_probe_read_str are captured in verifier.
Both helpers return a negative error code or
a length, which is equal to or smaller than the buffer
size argument. This additional information in the
verifier can avoid the condition such as "retval > bufsize"
in the bpf program. For example, for the code blow,
    usize = bpf_get_stack(ctx, raw_data, max_len, BPF_F_USER_STACK);
    if (usize < 0 || usize > max_len)
        return 0;
The verifier may have the following errors:
    52: (85) call bpf_get_stack#65
     R0=map_value(id=0,off=0,ks=4,vs=1600,imm=0) R1_w=ctx(id=0,off=0,imm=0)
     R2_w=map_value(id=0,off=0,ks=4,vs=1600,imm=0) R3_w=inv800 R4_w=inv256
     R6=ctx(id=0,off=0,imm=0) R7=map_value(id=0,off=0,ks=4,vs=1600,imm=0)
     R9_w=inv800 R10=fp0,call_-1
    53: (bf) r8 = r0
    54: (bf) r1 = r8
    55: (67) r1 <<= 32
    56: (bf) r2 = r1
    57: (77) r2 >>= 32
    58: (25) if r2 > 0x31f goto pc+33
     R0=inv(id=0) R1=inv(id=0,smax_value=9223372032559808512,
                         umax_value=18446744069414584320,
                         var_off=(0x0; 0xffffffff00000000))
     R2=inv(id=0,umax_value=799,var_off=(0x0; 0x3ff))
     R6=ctx(id=0,off=0,imm=0) R7=map_value(id=0,off=0,ks=4,vs=1600,imm=0)
     R8=inv(id=0) R9=inv800 R10=fp0,call_-1
    59: (1f) r9 -= r8
    60: (c7) r1 s>>= 32
    61: (bf) r2 = r7
    62: (0f) r2 += r1
    math between map_value pointer and register with unbounded
    min value is not allowed
The failure is due to llvm compiler optimization where register "r2",
which is a copy of "r1", is tested for condition while later on "r1"
is used for map_ptr operation. The verifier is not able to track such
inst sequence effectively.

Without the "usize > max_len" condition, there is no llvm optimization
and the below generated code passed verifier:
    52: (85) call bpf_get_stack#65
     R0=map_value(id=0,off=0,ks=4,vs=1600,imm=0) R1_w=ctx(id=0,off=0,imm=0)
     R2_w=map_value(id=0,off=0,ks=4,vs=1600,imm=0) R3_w=inv800 R4_w=inv256
     R6=ctx(id=0,off=0,imm=0) R7=map_value(id=0,off=0,ks=4,vs=1600,imm=0)
     R9_w=inv800 R10=fp0,call_-1
    53: (b7) r1 = 0
    54: (bf) r8 = r0
    55: (67) r8 <<= 32
    56: (c7) r8 s>>= 32
    57: (6d) if r1 s> r8 goto pc+24
     R0=inv(id=0,umax_value=800,var_off=(0x0; 0x3ff))
     R1=inv0 R6=ctx(id=0,off=0,imm=0)
     R7=map_value(id=0,off=0,ks=4,vs=1600,imm=0)
     R8=inv(id=0,umax_value=800,var_off=(0x0; 0x3ff)) R9=inv800
     R10=fp0,call_-1
    58: (bf) r2 = r7
    59: (0f) r2 += r8
    60: (1f) r9 -= r8
    61: (bf) r1 = r6

Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:53 -07:00
Yonghong Song
c195651e56 bpf: add bpf_get_stack helper
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>
2018-04-29 08:45:53 -07:00
Yonghong Song
5f41263274 bpf: change prototype for stack_map_get_build_id_offset
This patch didn't incur functionality change. The function prototype
got changed so that the same function can be reused later.

Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-04-29 08:45:53 -07:00
David S. Miller
79741a38b4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-04-27

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add extensive BPF helper description into include/uapi/linux/bpf.h
   and a new script bpf_helpers_doc.py which allows for generating a
   man page out of it. Thus, every helper in BPF now comes with proper
   function signature, detailed description and return code explanation,
   from Quentin.

2) Migrate the BPF collect metadata tunnel tests from BPF samples over
   to the BPF selftests and further extend them with v6 vxlan, geneve
   and ipip tests, simplify the ipip tests, improve documentation and
   convert to bpf_ntoh*() / bpf_hton*() api, from William.

3) Currently, helpers that expect ARG_PTR_TO_MAP_{KEY,VALUE} can only
   access stack and packet memory. Extend this to allow such helpers
   to also use map values, which enabled use cases where value from
   a first lookup can be directly used as a key for a second lookup,
   from Paul.

4) Add a new helper bpf_skb_get_xfrm_state() for tc BPF programs in
   order to retrieve XFRM state information containing SPI, peer
   address and reqid values, from Eyal.

5) Various optimizations in nfp driver's BPF JIT in order to turn ADD
   and SUB instructions with negative immediate into the opposite
   operation with a positive immediate such that nfp can better fit
   small immediates into instructions. Savings in instruction count
   up to 4% have been observed, from Jakub.

6) Add the BPF prog's gpl_compatible flag to struct bpf_prog_info
   and add support for dumping this through bpftool, from Jiri.

7) Move the BPF sockmap samples over into BPF selftests instead since
   sockmap was rather a series of tests than sample anyway and this way
   this can be run from automated bots, from John.

8) Follow-up fix for bpf_adjust_tail() helper in order to make it work
   with generic XDP, from Nikita.

9) Some follow-up cleanups to BTF, namely, removing unused defines from
   BTF uapi header and renaming 'name' struct btf_* members into name_off
   to make it more clear they are offsets into string section, from Martin.

10) Remove test_sock_addr from TEST_GEN_PROGS in BPF selftests since
    not run directly but invoked from test_sock_addr.sh, from Yonghong.

11) Remove redundant ret assignment in sample BPF loader, from Wang.

12) Add couple of missing files to BPF selftest's gitignore, from Anders.

There are two trivial merge conflicts while pulling:

  1) Remove samples/sockmap/Makefile since all sockmap tests have been
     moved to selftests.
  2) Add both hunks from tools/testing/selftests/bpf/.gitignore to the
     file since git should ignore all of them.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-26 21:19:50 -04:00
Jiri Olsa
b85fab0e67 bpf: Add gpl_compatible flag to struct bpf_prog_info
Adding gpl_compatible flag to struct bpf_prog_info
so it can be dumped via bpf_prog_get_info_by_fd and
displayed via bpftool progs dump.

Alexei noticed 4-byte hole in struct bpf_prog_info,
so we put the u32 flags field in there, and we can
keep adding bit fields in there without breaking
user space.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-26 22:36:11 +02:00
David S. Miller
a9537c937c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Merging net into net-next to help the bpf folks avoid
some really ugly merge conflicts.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-25 23:04:22 -04:00
David S. Miller
25eb0ea717 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Daniel Borkmann says:

====================
pull-request: bpf 2018-04-25

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix to clear the percpu metadata_dst that could otherwise carry
   stale ip_tunnel_info, from William.

2) Fix that reduces the number of passes in x64 JIT with regards to
   dead code sanitation to avoid risk of prog rejection, from Gianluca.

3) Several fixes of sockmap programs, besides others, fixing a double
   page_put() in error path, missing refcount hold for pinned sockmap,
   adding required -target bpf for clang in sample Makefile, from John.

4) Fix to disable preemption in __BPF_PROG_RUN_ARRAY() paths, from Roman.

5) Fix tools/bpf/ Makefile with regards to a lex/yacc build error
   seen on older gcc-5, from John.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-25 22:55:33 -04:00
David S. Miller
c749fa181b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-24 23:59:11 -04:00
Linus Torvalds
24cac7009c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
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
  ...
2018-04-24 14:16:40 -07:00
Paul Chaignon
d71962f3e6 bpf: allow map helpers access to map values directly
Helpers that expect ARG_PTR_TO_MAP_KEY and ARG_PTR_TO_MAP_VALUE can only
access stack and packet memory.  Allow these helpers to directly access
map values by passing registers of type PTR_TO_MAP_VALUE.

This change removes the need for an extra copy to the stack when using a
map value to perform a second map lookup, as in the following:

struct bpf_map_def SEC("maps") infobyreq = {
    .type = BPF_MAP_TYPE_HASHMAP,
    .key_size = sizeof(struct request *),
    .value_size = sizeof(struct info_t),
    .max_entries = 1024,
};
struct bpf_map_def SEC("maps") counts = {
    .type = BPF_MAP_TYPE_HASHMAP,
    .key_size = sizeof(struct info_t),
    .value_size = sizeof(u64),
    .max_entries = 1024,
};
SEC("kprobe/blk_account_io_start")
int bpf_blk_account_io_start(struct pt_regs *ctx)
{
    struct info_t *info = bpf_map_lookup_elem(&infobyreq, &ctx->di);
    u64 *count = bpf_map_lookup_elem(&counts, info);
    (*count)++;
}

Signed-off-by: Paul Chaignon <paul.chaignon@orange.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 22:39:13 +02:00
John Fastabend
4fcfdfb833 bpf: sockmap, fix double page_put on ENOMEM error in redirect path
In the case where the socket memory boundary is hit the redirect
path returns an ENOMEM error. However, before checking for this
condition the redirect scatterlist buffer is setup with a valid
page and length. This is never unwound so when the buffers are
released latter in the error path we do a put_page() and clear
the scatterlist fields. But, because the initial error happens
before completing the scatterlist buffer we end up with both the
original buffer and the redirect buffer pointing to the same page
resulting in duplicate put_page() calls.

To fix this simply move the initial configuration of the redirect
scatterlist buffer below the sock memory check.

Found this while running TCP_STREAM test with netperf using Cilium.

Fixes: fa246693a1 ("bpf: sockmap, BPF_F_INGRESS flag for BPF_SK_SKB_STREAM_VERDICT")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 00:49:45 +02:00
John Fastabend
e20f733483 bpf: sockmap, sk_wait_event needed to handle blocking cases
In the recvmsg handler we need to add a wait event to support the
blocking use cases. Without this we return zero and may confuse
user applications. In the wait event any data received on the
sk either via sk_receive_queue or the psock ingress list will
wake up the sock.

Fixes: fa246693a1 ("bpf: sockmap, BPF_F_INGRESS flag for BPF_SK_SKB_STREAM_VERDICT")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 00:49:45 +02:00
John Fastabend
ba6b8de423 bpf: sockmap, map_release does not hold refcnt for pinned maps
Relying on map_release hook to decrement the reference counts when a
map is removed only works if the map is not being pinned. In the
pinned case the ref is decremented immediately and the BPF programs
released. After this BPF programs may not be in-use which is not
what the user would expect.

This patch moves the release logic into bpf_map_put_uref() and brings
sockmap in-line with how a similar case is handled in prog array maps.

Fixes: 3d9e952697 ("bpf: sockmap, fix leaking maps with attached but not detached progs")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-24 00:49:45 +02:00
Martin KaFai Lau
fbcf93ebca bpf: btf: Clean up btf.h in uapi
This patch cleans up btf.h in uapi:
1) Rename "name" to "name_off" to better reflect it is an offset to the
   string section instead of a char array.
2) Remove unused value BTF_FLAGS_COMPR and BTF_MAGIC_SWAP

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-23 11:32:01 +02:00
David S. Miller
986e54cd68 Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
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>
2018-04-22 21:15:59 -04:00
Linus Torvalds
c1e9dae0a9 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
 "A small set of timer fixes:

   - Evaluate the -ETIME condition correctly in the imx tpm driver

   - Fix the evaluation order of a condition in posix cpu timers

   - Use pr_cont() in the clockevents code to prevent ugly message
     splitting

   - Remove __current_kernel_time() which is now unused to prevent that
     new users show up.

   - Remove a stale forward declaration"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/imx-tpm: Correct -ETIME return condition check
  posix-cpu-timers: Ensure set_process_cpu_timer is always evaluated
  timekeeping: Remove __current_kernel_time()
  timers: Remove stale struct tvec_base forward declaration
  clockevents: Fix kernel messages split across multiple lines
2018-04-22 10:49:02 -07:00
Linus Torvalds
38f0b33e6d Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
 "A larger set of updates for perf.

  Kernel:

   - Handle the SBOX uncore monitoring correctly on Broadwell CPUs which
     do not have SBOX.

   - Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]. The
     percentage of preempting and non-preempting context switches help
     understanding the nature of workloads (CPU or IO bound) that are
     running on a machine. This adds the kernel facility and userspace
     changes needed to show this information in 'perf script' and 'perf
     report -D' (Alexey Budankov)

   - Remove a WARN_ON() in the trace/kprobes code which is pointless
     because the return error code is already telling the caller what's
     wrong.

   - Revert a fugly workaround for clang BPF targets.

   - Fix sample_max_stack maximum check and do not proceed when an error
     has been detect, return them to avoid misidentifying errors (Jiri
     Olsa)

   - Add SPDX idenitifiers and get rid of GPL boilderplate.

  Tools:

   - Synchronize kernel ABI headers, v4.17-rc1 (Ingo Molnar)

   - Support MAP_FIXED_NOREPLACE, noticed when updating the
     tools/include/ copies (Arnaldo Carvalho de Melo)

   - Add '\n' at the end of parse-options error messages (Ravi Bangoria)

   - Add s390 support for detailed/verbose PMU event description (Thomas
     Richter)

   - perf annotate fixes and improvements:

      * Allow showing offsets in more than just jump targets, use the
        new 'O' hotkey in the TUI, config ~/.perfconfig
        annotate.offset_level for it and for --stdio2 (Arnaldo Carvalho
        de Melo)

      * Use the resolved variable names from objdump disassembled lines
        to make them more compact, just like was already done for some
        instructions, like "mov", this eventually will be done more
        generally, but lets now add some more to the existing mechanism
        (Arnaldo Carvalho de Melo)

   - perf record fixes:

      * Change warning for missing topology sysfs entry to debug, as not
        all architectures have those files, s390 being one of those
        (Thomas Richter)

      * Remove old error messages about things that unlikely to be the
        root cause in modern systems (Andi Kleen)

   - perf sched fixes:

      * Fix -g/--call-graph documentation (Takuya Yamamoto)

   - perf stat:

      * Enable 1ms interval for printing event counters values in
        (Alexey Budankov)

   - perf test fixes:

      * Run dwarf unwind on arm32 (Kim Phillips)

      * Remove unused ptrace.h include from LLVM test, sidesteping older
        clang's lack of support for some asm constructs (Arnaldo
        Carvalho de Melo)

      * Fixup BPF test using epoll_pwait syscall function probe, to cope
        with the syscall routines renames performed in this development
        cycle (Arnaldo Carvalho de Melo)

   - perf version fixes:

      * Do not print info about HAVE_LIBAUDIT_SUPPORT in 'perf version
        --build-options' when HAVE_SYSCALL_TABLE_SUPPORT is true, as
        libaudit won't be used in that case, print info about
        syscall_table support instead (Jin Yao)

   - Build system fixes:

      * Use HAVE_..._SUPPORT used consistently (Jin Yao)

      * Restore READ_ONCE() C++ compatibility in tools/include (Mark
        Rutland)

      * Give hints about package names needed to build jvmti (Arnaldo
        Carvalho de Melo)"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
  perf/x86/intel/uncore: Fix SBOX support for Broadwell CPUs
  perf/x86/intel/uncore: Revert "Remove SBOX support for Broadwell server"
  coresight: Move to SPDX identifier
  perf test BPF: Fixup BPF test using epoll_pwait syscall function probe
  perf tests mmap: Show which tracepoint is failing
  perf tools: Add '\n' at the end of parse-options error messages
  perf record: Remove suggestion to enable APIC
  perf record: Remove misleading error suggestion
  perf hists browser: Clarify top/report browser help
  perf mem: Allow all record/report options
  perf trace: Support MAP_FIXED_NOREPLACE
  perf: Remove superfluous allocation error check
  perf: Fix sample_max_stack maximum check
  perf: Return proper values for user stack errors
  perf list: Add s390 support for detailed/verbose PMU event description
  perf script: Extend misc field decoding with switch out event type
  perf report: Extend raw dump (-D) out with switch out event type
  perf/core: Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]
  tools/headers: Synchronize kernel ABI headers, v4.17-rc1
  trace_kprobe: Remove warning message "Could not insert probe at..."
  ...
2018-04-22 10:17:01 -07:00
David S. Miller
e0ada51db9 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were simple overlapping changes in microchip
driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-21 16:32:48 -04:00
Kees Cook
e01e80634e fork: unconditionally clear stack on fork
One of the classes of kernel stack content leaks[1] is exposing the
contents of prior heap or stack contents when a new process stack is
allocated.  Normally, those stacks are not zeroed, and the old contents
remain in place.  In the face of stack content exposure flaws, those
contents can leak to userspace.

Fixing this will make the kernel no longer vulnerable to these flaws, as
the stack will be wiped each time a stack is assigned to a new process.
There's not a meaningful change in runtime performance; it almost looks
like it provides a benefit.

Performing back-to-back kernel builds before:
	Run times: 157.86 157.09 158.90 160.94 160.80
	Mean: 159.12
	Std Dev: 1.54

and after:
	Run times: 159.31 157.34 156.71 158.15 160.81
	Mean: 158.46
	Std Dev: 1.46

Instead of making this a build or runtime config, Andy Lutomirski
recommended this just be enabled by default.

[1] A noisy search for many kinds of stack content leaks can be seen here:
https://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=linux+kernel+stack+leak

I did some more with perf and cycle counts on running 100,000 execs of
/bin/true.

before:
Cycles: 218858861551 218853036130 214727610969 227656844122 224980542841
Mean:  221015379122.60
Std Dev: 4662486552.47

after:
Cycles: 213868945060 213119275204 211820169456 224426673259 225489986348
Mean:  217745009865.40
Std Dev: 5935559279.99

It continues to look like it's faster, though the deviation is rather
wide, but I'm not sure what I could do that would be less noisy.  I'm
open to ideas!

Link: http://lkml.kernel.org/r/20180221021659.GA37073@beast
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Cc: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-20 17:18:35 -07:00
Jann Horn
6ab690aa43 bpf: sockmap remove dead check
Remove dead code that bails on `attr->value_size > KMALLOC_MAX_SIZE` - the
previous check already bails on `attr->value_size != 4`.

Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-20 22:09:51 +02:00
Linus Torvalds
41e3bef52e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching
Pull livepatching fix from Jiri Kosina:
 "Shadow variable API list_head initialization fix from Petr Mladek"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching:
  livepatch: Allow to call a custom callback when freeing shadow variables
  livepatch: Initialize shadow variables safely by a custom callback
2018-04-20 08:51:55 -07:00
Martin KaFai Lau
a26ca7c982 bpf: btf: Add pretty print support to the basic arraymap
This patch adds pretty print support to the basic arraymap.
Support for other bpf maps can be added later.

This patch adds new attrs to the BPF_MAP_CREATE command to allow
specifying the btf_fd, btf_key_id and btf_value_id.  The
BPF_MAP_CREATE can then associate the btf to the map if
the creating map supports BTF.

A BTF supported map needs to implement two new map ops,
map_seq_show_elem() and map_check_btf().  This patch has
implemented these new map ops for the basic arraymap.

It also adds file_operations, bpffs_map_fops, to the pinned
map such that the pinned map can be opened and read.
After that, the user has an intuitive way to do
"cat bpffs/pathto/a-pinned-map" instead of getting
an error.

bpffs_map_fops should not be extended further to support
other operations.  Other operations (e.g. write/key-lookup...)
should be realized by the userspace tools (e.g. bpftool) through
the BPF_OBJ_GET_INFO_BY_FD, map's lookup/update interface...etc.
Follow up patches will allow the userspace to obtain
the BTF from a map-fd.

Here is a sample output when reading a pinned arraymap
with the following map's value:

struct map_value {
	int count_a;
	int count_b;
};

cat /sys/fs/bpf/pinned_array_map:

0: {1,2}
1: {3,4}
2: {5,6}
...

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:46:25 +02:00
Martin KaFai Lau
60197cfb6e bpf: btf: Add BPF_OBJ_GET_INFO_BY_FD support to BTF fd
This patch adds BPF_OBJ_GET_INFO_BY_FD support to BTF fd.
The original BTF data, which was used to create the BTF fd during
the earlier BPF_BTF_LOAD call, will be returned.

The userspace is expected to allocate buffer
to info.info and the buffer size is set to info.info_len before
calling BPF_OBJ_GET_INFO_BY_FD.

The original BTF data is copied to the userspace buffer (info.info).
Only upto the user's specified info.info_len will be copied.

The original BTF data size is set to info.info_len.  The userspace
needs to check if it is bigger than its allocated buffer size.
If it is, the userspace should realloc with the kernel-returned
info.info_len and call the BPF_OBJ_GET_INFO_BY_FD again.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:46:25 +02:00
Martin KaFai Lau
f56a653c1f bpf: btf: Add BPF_BTF_LOAD command
This patch adds a BPF_BTF_LOAD command which
1) loads and verifies the BTF (implemented in earlier patches)
2) returns a BTF fd to userspace.  In the next patch, the
   BTF fd can be specified during BPF_MAP_CREATE.

It currently limits to CAP_SYS_ADMIN.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:46:25 +02:00
Martin KaFai Lau
b00b8daec8 bpf: btf: Add pretty print capability for data with BTF type info
This patch adds pretty print capability for data with BTF type info.
The current usage is to allow pretty print for a BPF map.

The next few patches will allow a read() on a pinned map with BTF
type info for its key and value.

This patch uses the seq_printf() infra.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:46:25 +02:00
Martin KaFai Lau
179cde8cef bpf: btf: Check members of struct/union
This patch checks a few things of struct's members:

1) It has a valid size (e.g. a "const void" is invalid)
2) A member's size (+ its member's offset) does not exceed
   the containing struct's size.
3) The member's offset satisfies the alignment requirement

The above can only be done after the needs_resolve member's type
is resolved.  Hence, the above is done together in
btf_struct_resolve().

Each possible member's type (e.g. int, enum, modifier...) implements
the check_member() ops which will be called from btf_struct_resolve().

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:46:24 +02:00
Martin KaFai Lau
eb3f595dab bpf: btf: Validate type reference
After collecting all btf_type in the first pass in an earlier patch,
the second pass (in this patch) can validate the reference types
(e.g. the referring type does exist and it does not refer to itself).

While checking the reference type, it also gathers other information (e.g.
the size of an array).  This info will be useful in checking the
struct's members in a later patch.  They will also be useful in doing
pretty print later.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:46:24 +02:00
Martin KaFai Lau
69b693f0ae bpf: btf: Introduce BPF Type Format (BTF)
This patch introduces BPF type Format (BTF).

BTF (BPF Type Format) is the meta data format which describes
the data types of BPF program/map.  Hence, it basically focus
on the C programming language which the modern BPF is primary
using.  The first use case is to provide a generic pretty print
capability for a BPF map.

BTF has its root from CTF (Compact C-Type format).  To simplify
the handling of BTF data, BTF removes the differences between
small and big type/struct-member.  Hence, BTF consistently uses u32
instead of supporting both "one u16" and "two u32 (+padding)" in
describing type and struct-member.

It also raises the number of types (and functions) limit
from 0x7fff to 0x7fffffff.

Due to the above changes,  the format is not compatible to CTF.
Hence, BTF starts with a new BTF_MAGIC and version number.

This patch does the first verification pass to the BTF.  The first
pass checks:
1. meta-data size (e.g. It does not go beyond the total btf's size)
2. name_offset is valid
3. Each BTF_KIND (e.g. int, enum, struct....) does its
   own check of its meta-data.

Some other checks, like checking a struct's member is referring
to a valid type, can only be done in the second pass.  The second
verification pass will be implemented in the next patch.

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-04-19 21:46:24 +02:00
Laura Abbott
c3bca5d450 posix-cpu-timers: Ensure set_process_cpu_timer is always evaluated
Commit a9445e47d8 ("posix-cpu-timers: Make set_process_cpu_timer()
more robust") moved the check into the 'if' statement. Unfortunately,
it did so on the right side of an && which means that it may get short
circuited and never evaluated. This is easily reproduced with:

$ cat loop.c
void main() {
  struct rlimit res;
  /* set the CPU time limit */
  getrlimit(RLIMIT_CPU,&res);
  res.rlim_cur = 2;
  res.rlim_max = 2;
  setrlimit(RLIMIT_CPU,&res);

  while (1);
}

Which will hang forever instead of being killed. Fix this by pulling the
evaluation out of the if statement but checking the return value instead.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1568337
Fixes: a9445e47d8 ("posix-cpu-timers: Make set_process_cpu_timer() more robust")
Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Cc: "Max R . P . Grossmann" <m@max.pm>
Cc: John Stultz <john.stultz@linaro.org>
Link: https://lkml.kernel.org/r/20180417215742.2521-1-labbott@redhat.com
2018-04-19 12:54:57 +02:00
Baolin Wang
e142aa09ed timekeeping: Remove __current_kernel_time()
The __current_kernel_time() function based on 'struct timespec' is no
longer recommended for new code, and the only user of this function has
been replaced by commit 6909e29fde ("kdb: use __ktime_get_real_seconds
instead of __current_kernel_time").

Remove the obsolete interface.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: sboyd@kernel.org
Cc: broonie@kernel.org
Cc: john.stultz@linaro.org
Link: https://lkml.kernel.org/r/1a9dbea7ee2cda7efe9ed330874075cf17fdbff6.1523596316.git.baolin.wang@linaro.org
2018-04-17 17:18:05 +02:00
Geert Uytterhoeven
4450dc0ae2 clockevents: Fix kernel messages split across multiple lines
Convert the clockevents driver from old-style printk() to pr_info() and
pr_cont(), to fix split kernel messages like below:

    Clockevents: could not switch to one-shot mode:
     dummy_timer is not functional.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: https://lkml.kernel.org/r/1522942018-14471-1-git-send-email-geert%2Brenesas@glider.be
2018-04-17 17:18:04 +02:00
Jesper Dangaard Brouer
039930945a xdp: transition into using xdp_frame for return API
Changing API xdp_return_frame() to take struct xdp_frame as argument,
seems like a natural choice. But there are some subtle performance
details here that needs extra care, which is a deliberate choice.

When de-referencing xdp_frame on a remote CPU during DMA-TX
completion, result in the cache-line is change to "Shared"
state. Later when the page is reused for RX, then this xdp_frame
cache-line is written, which change the state to "Modified".

This situation already happens (naturally) for, virtio_net, tun and
cpumap as the xdp_frame pointer is the queued object.  In tun and
cpumap, the ptr_ring is used for efficiently transferring cache-lines
(with pointers) between CPUs. Thus, the only option is to
de-referencing xdp_frame.

It is only the ixgbe driver that had an optimization, in which it can
avoid doing the de-reference of xdp_frame.  The driver already have
TX-ring queue, which (in case of remote DMA-TX completion) have to be
transferred between CPUs anyhow.  In this data area, we stored a
struct xdp_mem_info and a data pointer, which allowed us to avoid
de-referencing xdp_frame.

To compensate for this, a prefetchw is used for telling the cache
coherency protocol about our access pattern.  My benchmarks show that
this prefetchw is enough to compensate the ixgbe driver.

V7: Adjust for commit d9314c474d ("i40e: add support for XDP_REDIRECT")
V8: Adjust for commit bd658dda42 ("net/mlx5e: Separate dma base address
and offset in dma_sync call")

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 10:50:29 -04:00
Jesper Dangaard Brouer
70280ed91c bpf: cpumap convert to use generic xdp_frame
The generic xdp_frame format, was inspired by the cpumap own internal
xdp_pkt format.  It is now time to convert it over to the generic
xdp_frame format.  The cpumap needs one extra field dev_rx.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 10:50:28 -04:00
Jesper Dangaard Brouer
5ab073ffd3 xdp: introduce xdp_return_frame API and use in cpumap
Introduce an xdp_return_frame API, and convert over cpumap as
the first user, given it have queued XDP frame structure to leverage.

V3: Cleanup and remove C99 style comments, pointed out by Alex Duyck.
V6: Remove comment that id will be added later (Req by Alex Duyck)
V8: Rename enum mem_type to xdp_mem_type (found by kbuild test robot)

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17 10:50:27 -04:00
Jiri Olsa
bfb3d7b8b9 perf: Remove superfluous allocation error check
If the get_callchain_buffers fails to allocate the buffer it will
decrease the nr_callchain_events right away.

There's no point of checking the allocation error for
nr_callchain_events > 1. Removing that check.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: syzkaller-bugs@googlegroups.com
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/20180415092352.12403-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17 09:47:40 -03:00
Jiri Olsa
5af44ca53d perf: Fix sample_max_stack maximum check
The syzbot hit KASAN bug in perf_callchain_store having the entry stored
behind the allocated bounds [1].

We miss the sample_max_stack check for the initial event that allocates
callchain buffers. This missing check allows to create an event with
sample_max_stack value bigger than the global sysctl maximum:

  # sysctl -a | grep perf_event_max_stack
  kernel.perf_event_max_stack = 127

  # perf record -vv -C 1 -e cycles/max-stack=256/ kill
  ...
  perf_event_attr:
    size                             112
    ...
    sample_max_stack                 256
  ------------------------------------------------------------
  sys_perf_event_open: pid -1  cpu 1  group_fd -1  flags 0x8 = 4

Note the '-C 1', which forces perf record to create just single event.
Otherwise it opens event for every cpu, then the sample_max_stack check
fails on the second event and all's fine.

The fix is to run the sample_max_stack check also for the first event
with callchains.

[1] https://marc.info/?l=linux-kernel&m=152352732920874&w=2

Reported-by: syzbot+7c449856228b63ac951e@syzkaller.appspotmail.com
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: syzkaller-bugs@googlegroups.com
Cc: x86@kernel.org
Fixes: 97c79a38cd ("perf core: Per event callchain limit")
Link: http://lkml.kernel.org/r/20180415092352.12403-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17 09:47:40 -03:00
Jiri Olsa
78b562fbfa perf: Return proper values for user stack errors
Return immediately when we find issue in the user stack checks. The
error value could get overwritten by following check for
PERF_SAMPLE_REGS_INTR.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: syzkaller-bugs@googlegroups.com
Cc: x86@kernel.org
Fixes: 60e2364e60 ("perf: Add ability to sample machine state on interrupt")
Link: http://lkml.kernel.org/r/20180415092352.12403-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17 09:47:39 -03:00
Alexey Budankov
101592b490 perf/core: Store context switch out type in PERF_RECORD_SWITCH[_CPU_WIDE]
Store preempting context switch out event into Perf trace as a part of
PERF_RECORD_SWITCH[_CPU_WIDE] record.

Percentage of preempting and non-preempting context switches help
understanding the nature of workloads (CPU or IO bound) that are running
on a machine;

The event is treated as preemption one when task->state value of the
thread being switched out is TASK_RUNNING. Event type encoding is
implemented using PERF_RECORD_MISC_SWITCH_OUT_PREEMPT bit;

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/9ff84e83-a0ca-dd82-a6d0-cb951689be74@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-04-17 09:47:39 -03:00
Petr Mladek
3b2c77d000 livepatch: Allow to call a custom callback when freeing shadow variables
We might need to do some actions before the shadow variable is freed.
For example, we might need to remove it from a list or free some data
that it points to.

This is already possible now. The user can get the shadow variable
by klp_shadow_get(), do the necessary actions, and then call
klp_shadow_free().

This patch allows to do it a more elegant way. The user could implement
the needed actions in a callback that is passed to klp_shadow_free()
as a parameter. The callback usually does reverse operations to
the constructor callback that can be called by klp_shadow_*alloc().

It is especially useful for klp_shadow_free_all(). There we need to do
these extra actions for each found shadow variable with the given ID.

Note that the memory used by the shadow variable itself is still released
later by rcu callback. It is needed to protect internal structures that
keep all shadow variables. But the destructor is called immediately.
The shadow variable must not be access anyway after klp_shadow_free()
is called. The user is responsible to protect this any suitable way.

Be aware that the destructor is called under klp_shadow_lock. It is
the same as for the contructor in klp_shadow_alloc().

Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-04-17 13:42:48 +02:00
Petr Mladek
e91c2518a5 livepatch: Initialize shadow variables safely by a custom callback
The existing API allows to pass a sample data to initialize the shadow
data. It works well when the data are position independent. But it fails
miserably when we need to set a pointer to the shadow structure itself.

Unfortunately, we might need to initialize the pointer surprisingly
often because of struct list_head. It is even worse because the list
might be hidden in other common structures, for example, struct mutex,
struct wait_queue_head.

For example, this was needed to fix races in ALSA sequencer. It required
to add mutex into struct snd_seq_client. See commit b3defb791b
("ALSA: seq: Make ioctls race-free") and commit d15d662e89
("ALSA: seq: Fix racy pool initializations")

This patch makes the API more safe. A custom constructor function and data
are passed to klp_shadow_*alloc() functions instead of the sample data.

Note that ctor_data are no longer a template for shadow->data. It might
point to any data that might be necessary when the constructor is called.

Also note that the constructor is called under klp_shadow_lock. It is
an internal spin_lock that synchronizes alloc() vs. get() operations,
see klp_shadow_get_or_alloc(). On one hand, this adds a risk of ABBA
deadlocks. On the other hand, it allows to do some operations safely.
For example, we could add the new structure into an existing list.
This must be done only once when the structure is allocated.

Reported-by: Nicolai Stange <nstange@suse.de>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2018-04-17 13:42:48 +02:00
Song Liu
5c8dad48e4 trace_kprobe: Remove warning message "Could not insert probe at..."
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>
2018-04-17 07:54:57 +02:00
Linus Torvalds
9fb71c2f23 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
 "A set of fixes and updates for x86:

   - Address a swiotlb regression which was caused by the recent DMA
     rework and made driver fail because dma_direct_supported() returned
     false

   - Fix a signedness bug in the APIC ID validation which caused invalid
     APIC IDs to be detected as valid thereby bloating the CPU possible
     space.

   - Fix inconsisten config dependcy/select magic for the MFD_CS5535
     driver.

   - Fix a corruption of the physical address space bits when encryption
     has reduced the address space and late cpuinfo updates overwrite
     the reduced bit information with the original value.

   - Dominiks syscall rework which consolidates the architecture
     specific syscall functions so all syscalls can be wrapped with the
     same macros. This allows to switch x86/64 to struct pt_regs based
     syscalls. Extend the clearing of user space controlled registers in
     the entry patch to the lower registers"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Fix signedness bug in APIC ID validity checks
  x86/cpu: Prevent cpuinfo_x86::x86_phys_bits adjustment corruption
  x86/olpc: Fix inconsistent MFD_CS5535 configuration
  swiotlb: Use dma_direct_supported() for swiotlb_ops
  syscalls/x86: Adapt syscall_wrapper.h to the new syscall stub naming convention
  syscalls/core, syscalls/x86: Rename struct pt_regs-based sys_*() to __x64_sys_*()
  syscalls/core, syscalls/x86: Clean up compat syscall stub naming convention
  syscalls/core, syscalls/x86: Clean up syscall stub naming convention
  syscalls/x86: Extend register clearing on syscall entry to lower registers
  syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls on x86_64
  syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32
  syscalls/core: Prepare CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y for compat syscalls
  syscalls/x86: Use 'struct pt_regs' based syscall calling convention for 64-bit syscalls
  syscalls/core: Introduce CONFIG_ARCH_HAS_SYSCALL_WRAPPER=y
  x86/syscalls: Don't pointlessly reload the system call number
  x86/mm: Fix documentation of module mapping range with 4-level paging
  x86/cpuid: Switch to 'static const' specifier
2018-04-15 16:12:35 -07:00
Linus Torvalds
71b8ebbf3d Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Thomas Gleixner:
 "A few scheduler fixes:

   - Prevent a bogus warning vs. runqueue clock update flags in
     do_sched_rt_period_timer()

   - Simplify the helper functions which handle requests for skipping
     the runqueue clock updat.

   - Do not unlock the tunables mutex in the error path of the cpu
     frequency scheduler utils. Its not held.

   - Enforce proper alignement for 'struct util_est' in sched_avg to
     prevent a misalignment fault on IA64"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Force proper alignment of 'struct util_est'
  sched/core: Simplify helpers for rq clock update skip requests
  sched/rt: Fix rq->clock_update_flags < RQCF_ACT_SKIP warning
  sched/cpufreq/schedutil: Fix error path mutex unlock
2018-04-15 12:43:30 -07:00
Linus Torvalds
174e719439 Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
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 ')'
  ...
2018-04-15 12:36:31 -07:00
Linus Torvalds
68d54d3ff3 Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq affinity fixes from Thomas Gleixner:

  - Fix error path handling in the affinity spreading code

  - Make affinity spreading smarter to avoid issues on systems which
    claim to have hotpluggable CPUs while in fact they can't hotplug
    anything.

    So instead of trying to spread the vectors (and thereby the
    associated device queues) to all possibe CPUs, spread them on all
    present CPUs first. If there are left over vectors after that first
    step they are spread among the possible, but not present CPUs which
    keeps the code backwards compatible for virtual decives and NVME
    which allocate a queue per possible CPU, but makes the spreading
    smarter for devices which have less queues than possible or present
    CPUs.

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/affinity: Spread irq vectors among present CPUs as far as possible
  genirq/affinity: Allow irq spreading from a given starting point
  genirq/affinity: Move actual irq vector spreading into a helper function
  genirq/affinity: Rename *node_to_possible_cpumask as *node_to_cpumask
  genirq/affinity: Don't return with empty affinity masks on error
2018-04-15 12:29:46 -07:00