Re: Failure in syscall.open probe

[David Smith <dsmith at redhat dot com>]

Arkady,

The "good" news is that I've duplicated your problem. I went ahead and
filed PR22012 (<https://sourceware.org/bugzilla/show_bug.cgi?id=22012>)
on this issue so I won't forget it.

I'm looking into it.


On Fri, Aug 25, 2017 at 12:25 PM, Arkady <arkady.miasnikov@gmail.com> wrote:
> Reproduce the problem
>
> Run the following one liner on CentOS 6.9
>
> stap -e "global AF%;probe syscall.open {tid = tid();AF[tid] =
> filename;}probe syscall.open.return{tid = tid();delete AF[tid];}"
>
> Run a bash loop
> touch test.txt;while [ 1 ];do cat test.txt;done;
>
> Monitor the kernel log
> tail -f /var/log/messages
>
> After a couple of minutes you shall see
>
> BUG: scheduling while atomic: cat/87764/0x10000001
> Modules linked in: test_open(U) fuse rfcomm sco bridge bnep l2cap
> autofs4 bnx2fc cnic uio fcoe libfcoe libfc 8021q scsi_transport_fc
> garp stp scsi_tgt llc ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4
> iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6
> xt_state nf_conntrack ip6table_filter ip6_tables ib_ipoib rdma_ucm
> ib_ucm ib_uverbs ib_umad rdma_cm ib_cm iw_cm ib_sa ib_mad ib_core
> ib_addr ipv6 uinput microcode vmware_balloon uvcvideo videodev
> v4l2_compat_ioctl32 btusb bluetooth rfkill snd_seq_midi e1000
> snd_seq_midi_event snd_ens1371 snd_rawmidi snd_ac97_codec ac97_bus
> snd_seq snd_seq_device snd_pcm snd_timer snd soundcore snd_page_alloc
> sg i2c_piix4 shpchp ext4 jbd2 mbcache sd_mod crc_t10dif sr_mod cdrom
> mptspi mptscsih mptbase scsi_transport_spi pata_acpi ata_generic
> ata_piix vmwgfx ttm drm_kms_helper drm i2c_core dm_mirror
> dm_region_hash dm_log dm_mod [last unloaded: speedstep_lib]
> Pid: 87764, comm: cat Not tainted 2.6.32-696.10.1.el6.x86_64 #1
> Call Trace:
> <#DB>  [<ffffffff81068244>] ? __schedule_bug+0x44/0x50
> [<ffffffff8154ae0c>] ? schedule+0xa4c/0xb70
> [<ffffffff812a6216>] ? vsnprintf+0x336/0x5e0
> [<ffffffff810740aa>] ? __cond_resched+0x2a/0x40
> [<ffffffff8154b200>] ? _cond_resched+0x30/0x40
> [<ffffffff812a8b9a>] ? strncpy_from_user+0x4a/0x90
> [<ffffffffa0705ff9>] ? probe_3602+0x5f9/0x1220 [test_open]
> [<ffffffff81196c31>] ? sys_open+0x1/0x30
> [<ffffffffa0707fed>] ? enter_kprobe_probe+0x1ed/0x3a0 [test_open]
> [<ffffffff815512bb>] ? aggr_pre_handler+0x5b/0xb0
> [<ffffffff81196c30>] ? sys_open+0x0/0x30
> [<ffffffff81196c31>] ? sys_open+0x1/0x30
> [<ffffffff81550cd5>] ? kprobe_exceptions_notify+0x3d5/0x430
> [<ffffffff81550f45>] ? notifier_call_chain+0x55/0x80
> [<ffffffff81550faa>] ? atomic_notifier_call_chain+0x1a/0x20
> [<ffffffff810acd0e>] ? notify_die+0x2e/0x30
> [<ffffffff8154e815>] ? do_int3+0x35/0xb0
> [<ffffffff8154e083>] ? int3+0x33/0x40
> [<ffffffff81196c30>] ? sys_open+0x0/0x30



-- 
David Smith
Principal Software Engineer
Red Hat