I am not able to reproduce the bug with latest net-next.
Thanks Daniel to point it out, looks like your test uses an old-version
unapplied patchset:
https://github.com/0day-ci/linux/commit/76cdd39f4117a6cbd520b5d09993ac87acbdcfd8
which yes, there is a bug to leak the mutext lock and the bug
is fixed in subsequent patch set.
FYI, we noticed the following commit (built with gcc-4.8):
commit: 76cdd39f4117a6cbd520b5d09993ac87acbdcfd8 ("bpf: permit multiple bpf
attachments for a single perf event")
url:
https://github.com/0day-ci/linux/commits/Yonghong-Song/bpf-permit-multiple-bpf-attachments-for-a-single-perf-tracepoint-event/20171024-080608
in testcase: boot
on test machine: qemu-system-x86_64 -enable-kvm -smp 2 -m 512M
caused below changes (please refer to attached dmesg/kmsg for entire
log/backtrace):
+----------------+------------+------------+
| | 052bd6a4fb | 76cdd39f41 |
+----------------+------------+------------+
| boot_successes | 64 | 66 |
+----------------+------------+------------+
[ 50.247341] WARNING: trinity-c0/3371 still has locks held!
[main] Random reseed: 4199236289
[ 50.258948] 4.14.0-rc5-01671-g76cdd39 #1 Not tainted
[ 50.260888] ------------------------------------
[child0:3373] io_getevents (208) returned ENOSYS, marking as inactive.
[child0:3373] sysfs (139) returned ENOSYS, marking as inactive.
[ 50.273066] 1 lock held by trinity-c0/3371:
[ 50.274247] #0: (bpf_event_mutex){....}, at: [<ffffffff811cd617>]
perf_event_detach_bpf_prog+0x17/0xd0
[child0:3373] fanotify_mark (301) returned ENOSYS, marking as inactive.
*** glibc detected *** /trinity: double free or corruption (out):
0x0000000001d51000 ***
[ 50.288585]
[ 50.288585] stack backtrace:
[ 50.290123] CPU: 1 PID: 3371 Comm: trinity-c0 Not tainted
4.14.0-rc5-01671-g76cdd39 #1
[ 50.292804] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.10.2-1 04/01/2014
[ 50.295763] Call Trace:
[ 50.296791] dump_stack+0xcb/0x13f
[ 50.298244] do_exit+0xf1f/0x1380
[ 50.299525] ? syscall_trace_enter+0x3ce/0x490
[ 50.301186] do_group_exit+0x9d/0x120
[ 50.302531] SyS_exit_group+0xb/0x10
[ 50.303746] do_syscall_64+0xa6/0x240
[ 50.305256] entry_SYSCALL64_slow_path+0x25/0x25
[ 50.306847] RIP: 0033:0x7f60b8dae408
[ 50.307944] RSP: 002b:00007fff020656e8 EFLAGS: 00000206 ORIG_RAX:
00000000000000e7
[ 50.310457] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f60b8dae408
[ 50.312482] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000
[ 50.314526] RBP: 00007fff020665a0 R08: 00000000000000e7 R09: ffffffffffffffa0
[ 50.316981] R10: 00007fff02065480 R11: 0000000000000206 R12: 0000000000000299
[ 50.319413] R13: 0000000000000059 R14: 00007fff02065d10 R15: 0000000000000002
======= Backtrace: =========
To reproduce:
git clone https://github.com/intel/lkp-tests.git
cd lkp-tests
bin/lkp qemu -k <bzImage> job-script # job-script is attached in this
email
Thanks,
Xiaolong
