On 9/21/21 12:40 AM, Dave Chinner wrote:
> Hi Jens,
>
> I updated all my trees from 5.14 to 5.15-rc2 this morning and
> immediately had problems running the recoveryloop fstest group on
> them. These tests have a typical pattern of "run load in the
> background, shutdown the filesystem, kill load, unmount and test
> recovery".
>
> Whent eh load includes fsstress, and it gets killed after shutdown,
> it hangs on exit like so:
>
> # echo w > /proc/sysrq-trigger
> [ 370.669482] sysrq: Show Blocked State
> [ 370.671732] task:fsstress state:D stack:11088 pid: 9619 ppid: 9615 flags:0x00000000
> [ 370.675870] Call Trace:
> [ 370.677067] __schedule+0x310/0x9f0
> [ 370.678564] schedule+0x67/0xe0
> [ 370.679545] schedule_timeout+0x114/0x160
> [ 370.682002] __wait_for_common+0xc0/0x160
> [ 370.684274] wait_for_completion+0x24/0x30
> [ 370.685471] do_coredump+0x202/0x1150
> [ 370.690270] get_signal+0x4c2/0x900
> [ 370.691305] arch_do_signal_or_restart+0x106/0x7a0
> [ 370.693888] exit_to_user_mode_prepare+0xfb/0x1d0
> [ 370.695241] syscall_exit_to_user_mode+0x17/0x40
> [ 370.696572] do_syscall_64+0x42/0x80
> [ 370.697620] entry_SYSCALL_64_after_hwframe+0x44/0xae
>
> It's 100% reproducable on one of my test machines, but only one of
> them. That one machine is running fstests on pmem, so it has
> synchronous storage. Every other test machine using normal async
> storage (nvme, iscsi, etc) and none of them are hanging.
>
> A quick troll of the commit history between 5.14 and 5.15-rc2
> indicates a couple of potential candidates. The 5th kernel build
> (instead of ~16 for a bisect) told me that commit 15e20db2e0ce
> ("io-wq: only exit on fatal signals") is the cause of the
> regression. I've confirmed that this is the first commit where the
> problem shows up.
Thanks for the report Dave, I'll take a look. Can you elaborate on
exactly what is being run? And when killed, it's a non-fatal signal?
--
Jens Axboe
