Re: Crashes during boot on 2.6.30 / 2.6.31-rc, random programs

[Amerigo Wang <xiyou.wangcong@gmail.com>]

On Mon, Jun 29, 2009 at 09:53:41AM +0100, Joao Correia wrote:
>Hello
>
>Well, it doesnt complain about MAX_STACK_TRACE_ENTRIES anymore, but
>now it gives me:
>
>BUG: MAX_LOCK_DEPTH too low!
>turning off the locking correctness validator.
>Pid: 1672, comm: qemu-kvm Not tainted 2.6.30-wl #2
>Call Trace:
> [<c07da76f>] ? printk+0x22/0x3b
> [<c0463de9>] __lock_acquire+0xa77/0xb05
> [<c0463f2e>] lock_acquire+0xb7/0xeb
> [<c04be96c>] ? mm_take_all_locks+0xb3/0xf1
> [<c04be96c>] ? mm_take_all_locks+0xb3/0xf1
> [<c07dd476>] _spin_lock_nest_lock+0x30/0x71
> [<c04be96c>] ? mm_take_all_locks+0xb3/0xf1
> [<c04be96c>] mm_take_all_locks+0xb3/0xf1
> [<c04cc741>] do_mmu_notifier_register+0x9f/0x14e
> [<c04cc83d>] mmu_notifier_register+0x1e/0x31
> [<f9e461b8>] kvm_dev_ioctl+0xfd/0x25d [kvm]
> [<f9e460bb>] ? kvm_dev_ioctl+0x0/0x25d [kvm]
> [<c04e4df6>] vfs_ioctl+0x29/0x91
> [<c04e52f4>] do_vfs_ioctl+0x496/0x4e3
> [<c07dfb82>] ? do_page_fault+0x229/0x26a
> [<c0408e41>] ? sched_clock+0x9/0xd
> [<c0461218>] ? lock_release_holdtime+0x39/0x143
> [<c07dfb82>] ? do_page_fault+0x229/0x26a
> [<c04e5396>] sys_ioctl+0x55/0x86
> [<c04037f3>] sysenter_do_call+0x12/0x38
>
>which looks like its younger brother :-). (Also appears on other
>programs, not just qemu-kvm)

Hmmm.. also known. :)

>
>Should i increase its value too? Am i not just masking something else
>by doing this?

Just try to modify your sysctl.conf file, on Fedora it should be
/etc/sysctl.conf, try to double the value of
/proc/sys/kernel/max_lock_depth.

If this doesn't work, try to increase the value of 'max_lock_depth'
in the kernel source. :)

I think Peter will have a patch to fix this.