From: Jens Axboe <axboe@kernel.dk>
To: Tejun Heo <tj@kernel.org>
Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
cgroups@vger.kernel.org, kernel-team@fb.com,
Dave Jones <davej@codemonkey.org.uk>
Subject: Re: [block/for-next] iocost: Fix incorrect operation order during iocg free
Date: Tue, 10 Sep 2019 12:21:14 -0600 [thread overview]
Message-ID: <2222732f-09f7-1434-31a6-b591630d2efb@kernel.dk> (raw)
In-Reply-To: <20190910161525.GT2263813@devbig004.ftw2.facebook.com>
On 9/10/19 10:15 AM, Tejun Heo wrote:
> ioc_pd_free() first cancels the hrtimers and then deactivates the
> iocg. However, the iocg timer can run inbetween and reschedule the
> hrtimers which will end up running after the iocg is freed leading to
> crashes like the following.
>
> general protection fault: 0000 [#1] SMP
> ...
> RIP: 0010:iocg_kick_delay+0xbe/0x1b0
> RSP: 0018:ffffc90003598ea0 EFLAGS: 00010046
> RAX: 1cee00fd69512b54 RBX: ffff8881bba48400 RCX: 00000000000003e8
> RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8881bba48400
> RBP: 0000000000004e20 R08: 0000000000000002 R09: 00000000000003e8
> R10: 0000000000000000 R11: 0000000000000000 R12: ffffc90003598ef0
> R13: 00979f3810ad461f R14: ffff8881bba4b400 R15: 25439f950d26e1d1
> FS: 0000000000000000(0000) GS:ffff88885f800000(0000) knlGS:0000000000000000
> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> CR2: 00007f64328c7e40 CR3: 0000000002409005 CR4: 00000000003606e0
> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> Call Trace:
> <IRQ>
> iocg_delay_timer_fn+0x3d/0x60
> __hrtimer_run_queues+0xfe/0x270
> hrtimer_interrupt+0xf4/0x210
> smp_apic_timer_interrupt+0x5e/0x120
> apic_timer_interrupt+0xf/0x20
> </IRQ>
>
> Fix it by canceling hrtimers after deactivating the iocg.
Applied, thanks.
--
Jens Axboe
prev parent reply other threads:[~2019-09-10 18:21 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-10 16:15 [block/for-next] iocost: Fix incorrect operation order during iocg free Tejun Heo
2019-09-10 18:21 ` Jens Axboe [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2222732f-09f7-1434-31a6-b591630d2efb@kernel.dk \
--to=axboe@kernel.dk \
--cc=cgroups@vger.kernel.org \
--cc=davej@codemonkey.org.uk \
--cc=kernel-team@fb.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).