public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: Avi Kivity <avi@redhat.com>
To: Andrea Arcangeli <aarcange@redhat.com>
Cc: Nikola Ciprich <extmaillist@linuxbox.cz>,
	KVM list <kvm@vger.kernel.org>,
	nikola.ciprich@linuxbox.cz
Subject: Re: kvm-85 sometimes not starting on 2.6.30-rc5
Date: Sun, 17 May 2009 23:27:42 +0300	[thread overview]
Message-ID: <4A10733E.5000905@redhat.com> (raw)
In-Reply-To: <20090513192249.GA5760@nik-comp.linuxbox.cz>

Andrea, looks like the mother of all locks below.

Nikola Ciprich wrote:
> Hi,
> sometimes trying to start kvm on 2.6.30-rc5 (with kvm module v85, userspace v85) fails with:
> kvm_create_vm: Interrupted system call
> Could not create KVM context
>
> and following backtrace appears in dmesg:
> [  309.546138] BUG: MAX_LOCK_DEPTH too low!
> [  309.549964] turning off the locking correctness validator.
> [  309.549964] Pid: 2833, comm: qemu-kvm Not tainted 2.6.30lb.00_01_PRE08 #1
> [  309.549964] Call Trace:
> [  309.549964]  [<ffffffff80269aa9>] __lock_acquire+0x4a9/0xb70
> [  309.549964]  [<ffffffff802c54ef>] ? mm_take_all_locks+0x2f/0x130
> [  309.549964]  [<ffffffff8026b825>] lock_acquire+0xa5/0x150
> [  309.549964]  [<ffffffff802c55ac>] ? mm_take_all_locks+0xec/0x130
> [  309.549964]  [<ffffffff80505c96>] _spin_lock_nest_lock+0x36/0x50
> [  309.549964]  [<ffffffff802c55ac>] ? mm_take_all_locks+0xec/0x130
> [  309.549964]  [<ffffffff802c55ac>] mm_take_all_locks+0xec/0x130
> [  309.549964]  [<ffffffff802d43ab>] do_mmu_notifier_register+0x7b/0x1d0
> [  309.549964]  [<ffffffff802d451e>] mmu_notifier_register+0xe/0x10
> [  309.549964]  [<ffffffffa02a8dd9>] kvm_dev_ioctl+0x189/0x2f0 [kvm]
> [  309.549964]  [<ffffffff802f0171>] vfs_ioctl+0x31/0x90
> [  309.549964]  [<ffffffff802f03fb>] do_vfs_ioctl+0x22b/0x550
> [  309.549964]  [<ffffffff802f07a2>] sys_ioctl+0x82/0xa0
> [  309.549964]  [<ffffffff8020b442>] system_call_fastpath+0x16/0x1b
>
> It happened to me when I didn't have storage with kernel mounted.
> Further attempts are usually successfull.
> BR
> nik
>
>
>   


-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.


  reply	other threads:[~2009-05-17 20:27 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-05-13 19:22 kvm-85 sometimes not starting on 2.6.30-rc5 Nikola Ciprich
2009-05-17 20:27 ` Avi Kivity [this message]
2009-05-23 17:20   ` Andrea Arcangeli
2009-05-24  9:47     ` Avi Kivity
2009-09-03  8:04       ` Nikola Ciprich

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=4A10733E.5000905@redhat.com \
    --to=avi@redhat.com \
    --cc=aarcange@redhat.com \
    --cc=extmaillist@linuxbox.cz \
    --cc=kvm@vger.kernel.org \
    --cc=nikola.ciprich@linuxbox.cz \
    /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