On 2017/1/23 下午10:16, Greg KH wrote: > On Mon, Jan 23, 2017 at 09:20:12PM +0800, colyli@xxxxxxx wrote: >> Hi stable maintainers, >> >> This patch is from Kent, upstream commit ID is be628be09563. >> Olav Reinert <seroton10@xxxxxxxxx> reports a kerenl crash from >> bcache (boo#1021260) and Oliver Nuekum points out this patch fixes the problem. > > "boo"? > Hi Greg, "boo" is abbreviation of bugzilla.opensuse.org, I paste the original bug report here, ==== start of bug report ========== I have starting seeing errors like the one quoted below in the system log. It occurs infrequently, but quite regularly, about 1-3 times a week, on a server running 24x7. Around the time it began, I started running a beta version of Leap 42.2, upgraded from 42.1. Also, I enabled the "discard" option (SSD TRIM) on the bcache cache about 3-6 months ago. I believe one of those two events caused the bug to appear. Not sure what other info is useful, please ask for whatever you need. Oct 10 00:00:02 blackbox kernel: ------------[ cut here ]------------ Oct 10 00:00:02 blackbox kernel: WARNING: CPU: 4 PID: 1269 at ../kernel/sched/core.c:7891 __might_sleep+0x76/0x80() Oct 10 00:00:02 blackbox kernel: do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffffa09e2325>] bch_gc_thread+0x25/0x100 [ Oct 10 00:00:02 blackbox kernel: Modules linked in: vhost_net vhost macvtap macvlan fuse ebt_arp ebt_ip ebtable_nat ebtable_filter ebtables Oct 10 00:00:02 blackbox kernel: mxm_wmi Oct 10 00:00:02 blackbox kernel: bcache aesni_intel raid1 snd_hda_codec_realtek aes_x86_64 lrw snd_hda_codec_generic gf128mul md_mod glue_h Oct 10 00:00:02 blackbox kernel: Oct 10 00:00:02 blackbox kernel: CPU: 4 PID: 1269 Comm: bcache_gc Not tainted 4.4.21-2-default #1 Oct 10 00:00:02 blackbox kernel: Hardware name: To be filled by O.E.M. To be filled by O.E.M./M5A99X EVO R2.0, BIOS 2301 01/06/2014 Oct 10 00:00:02 blackbox kernel: 0000000000000000 ffffffff81326967 ffff8800b605be10 ffffffff81a5e431 Oct 10 00:00:02 blackbox kernel: ffffffff8107e7d1 ffffffff81a5f54f ffff8800b605be60 0000000000000061 Oct 10 00:00:02 blackbox kernel: 0000000000000000 Oct 10 00:00:02 blackbox kernel: 0000000000000000 ffffffff8107e84c ffffffff81a4ef88 Oct 10 00:00:02 blackbox kernel: Call Trace: Oct 10 00:00:02 blackbox kernel: [<ffffffff81019e69>] dump_trace+0x59/0x320 Oct 10 00:00:02 blackbox kernel: [<ffffffff8101a22a>] show_stack_log_lvl+0xfa/0x180 Oct 10 00:00:02 blackbox kernel: [<ffffffff8101afd1>] show_stack+0x21/0x40 Oct 10 00:00:02 blackbox kernel: [<ffffffff81326967>] dump_stack+0x5c/0x85 Oct 10 00:00:02 blackbox kernel: [<ffffffff8107e7d1>] warn_slowpath_common+0x81/0xb0 Oct 10 00:00:02 blackbox kernel: [<ffffffff8107e84c>] warn_slowpath_fmt+0x4c/0x50 Oct 10 00:00:02 blackbox kernel: [<ffffffff810a3026>] __might_sleep+0x76/0x80 Oct 10 00:00:02 blackbox kernel: [<ffffffff81605cac>] mutex_lock+0x1c/0x38 Oct 10 00:00:02 blackbox kernel: [<ffffffffa09e2365>] bch_gc_thread+0x65/0x100 [bcache] Oct 10 00:00:02 blackbox kernel: [<ffffffff8109d268>] kthread+0xc8/0xe0 Oct 10 00:00:02 blackbox kernel: [<ffffffff8160828f>] ret_from_fork+0x3f/0x70 Oct 10 00:00:02 blackbox kernel: DWARF2 unwinder stuck at ret_from_fork+0x3f/0x70 Oct 10 00:00:02 blackbox kernel: Oct 10 00:00:02 blackbox kernel: Leftover inexact backtrace: Oct 10 00:00:02 blackbox kernel: [<ffffffff8109d1a0>] ? kthread_park+0x50/0x50 Oct 10 00:00:02 blackbox kernel: ---[ end trace c63abcb6c473e79b ]--- ==== end of bug report ========== # journalctl|grep "blocking ops" Oct 10 00:00:02 blackbox kernel: do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffffa09e2325>] bch_gc_thread+0x25/0x100 [bcache] [snip repeated lines] >> I send this patch to stable@xxxxxxxxxxxxxxx, hope this patch can be taken care >> in stable kernels. >> >> Thanks in advance. >> >> Coly Li >> >> Here I attach the original patch, just FYI. >> --- >> From: Kent Overstreet <kent.overstreet@xxxxxxxxx> >> Date: Wed, 26 Oct 2016 20:31:17 -0700 >> Subject: [PATCH] bcache: Make gc wakeup sane, remove set_task_state() >> >> Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx> > > No changelog text? Worst short changelog description ever? There is no change log from original patch, I am not the author, and it is in upstream already. So I think I am not the right person to change its commit log. This is the first time I encounter this situation, that send a patch to stable which is not from me. I guess Kent does not notice that this patch indeed fixes a kernel oops. But it does fix a bug report for Leap 42.2 and SLE12-SP2. > > This gives me no context of what is going on here. Why does this fix a > bug? What kernel(s) should it be backported to? > The bug is reported on Linux 4.4 based kernel, so at least all kernels since Linux 4.4 should have the fix. Maybe Kent can provide more accurate suggestion. Thanks. Coly -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html