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Tiezhu Yang 300a55a3a6 perf top: Skip side-band event setup if HAVE_LIBBPF_SUPPORT is not set
commit 0c5f1acc2a14416bf30023f373558d369afdbfc8 upstream.

When I execute 'perf top' without HAVE_LIBBPF_SUPPORT, there exists the
following segmentation fault, skip the side-band event setup to fix it,
this is similar with commit 1101c872c8c7 ("perf record: Skip side-band
event setup if HAVE_LIBBPF_SUPPORT is not set").

  [yangtiezhu@linux perf]$ ./perf top
  <SNIP>
  perf: Segmentation fault
  Obtained 6 stack frames.
  ./perf(sighandler_dump_stack+0x5c) [0x12011b604]
  [0xffffffc010]
  ./perf(perf_mmap__read_init+0x3e) [0x1201feeae]
  ./perf() [0x1200d715c]
  /lib64/libpthread.so.0(+0xab9c) [0xffee10ab9c]
  /lib64/libc.so.6(+0x128f4c) [0xffedc08f4c]
  Segmentation fault
  [yangtiezhu@linux perf]$

I use git bisect to find commit b38d85ef49cf ("perf bpf: Decouple
creating the evlist from adding the SB event") is the first bad commit,
so also add the Fixes tag.

Committer testing:

First build perf explicitely disabling libbpf:

  $ make NO_LIBBPF=1 O=/tmp/build/perf -C tools/perf install-bin && perf test python

Now make sure it isn't linked:

  $ perf -vv | grep -w bpf
                   bpf: [ OFF ]  # HAVE_LIBBPF_SUPPORT
  $
  $ nm ~/bin/perf | grep libbpf
  $

And now try to run 'perf top':

  # perf top
  perf: Segmentation fault
  -------- backtrace --------
  perf[0x5bcd6d]
  /lib64/libc.so.6(+0x3ca6f)[0x7fd0f5a66a6f]
  perf(perf_mmap__read_init+0x1e)[0x5e1afe]
  perf[0x4cc468]
  /lib64/libpthread.so.0(+0x9431)[0x7fd0f645a431]
  /lib64/libc.so.6(clone+0x42)[0x7fd0f5b2b912]
  #

Applying this patch fixes the issue.

Fixes: b38d85ef49cf ("perf bpf: Decouple creating the evlist from adding the SB event")
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Link: http://lore.kernel.org/lkml/1597753837-16222-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-25 14:34:33 -08:00
arch s390/pci: fix max size calculation in zpci_memcpy_toio() 2024-01-25 14:34:32 -08:00
block blk-throttle: fix lockdep warning of "cgroup_mutex or RCU read lock required!" 2023-12-20 15:41:20 +01:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: scomp - fix req->dst buffer overflow 2024-01-25 14:34:24 -08:00
Documentation firmware: ti_sci: Replace HTTP links with HTTPS ones 2023-11-20 10:30:12 +01:00
drivers i2c: s3c24xx: fix transferring more than one message in polling mode 2024-01-25 14:34:32 -08:00
fs f2fs: fix to avoid dirent corruption 2024-01-25 14:34:27 -08:00
include drm/bridge: Fix typo in post_disable() description 2024-01-25 14:34:27 -08:00
init rootfs: Fix support for rootfstype= when root= is given 2024-01-25 14:34:30 -08:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:23:06 +01:00
kernel kdb: Fix a potential buffer overflow in kdb_local() 2024-01-25 14:34:32 -08:00
lib ida: Fix crash in ida_free when the bitmap is empty 2024-01-25 14:34:21 -08:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
mm mm: fix unmap_mapping_range high bits shift bug 2024-01-15 18:25:28 +01:00
net ipvs: avoid stat macros calls from preemptible context 2024-01-25 14:34:32 -08:00
samples samples/bpf: Fix buffer overflow in tcp_basertt 2023-07-27 08:37:07 +02:00
scripts sign-file: Fix incorrect return values check 2023-12-20 15:41:17 +01:00
security apparmor: avoid crash when parsed profile name is empty 2024-01-25 14:34:31 -08:00
sound ALSA: oxygen: Fix right channel of capture volume mixer 2024-01-25 14:34:30 -08:00
tools perf top: Skip side-band event setup if HAVE_LIBBPF_SUPPORT is not set 2024-01-25 14:34:33 -08:00
usr initramfs: restore default compression behavior 2020-04-08 09:08:38 +02:00
virt KVM: Destroy target device if coalesced MMIO unregistration fails 2023-03-11 16:44:01 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
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.gitattributes
.gitignore Modules updates for v5.4 2019-09-22 10:34:46 -07:00
.mailmap ARM: SoC fixes 2019-11-10 13:41:59 -08:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS: Remove Simon as Renesas SoC Co-Maintainer 2019-10-10 08:12:51 -07:00
Kbuild kbuild: do not descend to ./Kbuild when cleaning 2019-08-21 21:03:58 +09:00
Kconfig docs: kbuild: convert docs to ReST and rename to *.rst 2019-06-14 14:21:21 -06:00
MAINTAINERS iio: stx104: Move to addac subdirectory 2023-08-30 16:27:12 +02:00
Makefile Linux 5.4.267 2024-01-15 18:25:30 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.