Re: "cat /proc/lockdep" after "rmmod <some module>" when !debug_locks will crash the system

From: Bart Van Assche
Date: Mon Mar 25 2019 - 20:55:22 EST


On 3/25/19 5:27 PM, shenghui wrote:
On 3/26/19 1:06 AM, Bart Van Assche wrote:
On Mon, 2019-03-25 at 17:45 +0800, shenghui wrote:
[ 47.103637] vboxdrv: loading out-of-tree module taints kernel.
[ 47.111919] vboxdrv: Found 2 processor cores
[ 47.119013] vboxdrv: fAsync=0 offMin=0x2ee offMax=0x13f7
> [ ...........] ...
> [ 47.219043] DEBUG_LOCKS_WARN_ON(!current->hardirqs_enabled)
> [ 47.219055] WARNING: CPU: 0 PID: 844 at kernel/locking/lockdep.c:4142 check_flags.part.45+0x9e/0x190
[ 47.219142] Call Trace:
[ 47.219148] lock_acquire+0x3a/0x150
[ 47.219153] fs_reclaim_acquire.part.106+0x21/0x30
[ 47.219156] ? fs_reclaim_acquire.part.106+0x5/0x30
[ 47.219159] fs_reclaim_acquire+0x1d/0x20
[ 47.219163] __kmalloc+0x4d/0x280
[ 47.219192] ? rtR0MemAllocEx+0xaf/0x110 [vboxdrv]
[ 47.219210] ? supdrvGipInitMeasureTscFreq+0x15c/0x460 [vboxdrv]
[ 47.219229] rtR0MemAllocEx+0xaf/0x110 [vboxdrv]
[ 47.219247] ? supdrvTscDeltaThreadStartMeasurement.part.5+0x80/0x80 [vboxdrv]
[ 47.219265] VBoxHost_RTMemAllocTag+0x23/0x50 [vboxdrv]
[ 47.219284] VBoxHost_RTMpNotificationRegister+0x97/0x170 [vboxdrv]

Hi Shenghui,

I have not found the VBoxHost_RTMpNotificationRegister function name anywhere in the kernel tree. I think that means that this warning is generated by an out-of-tree driver. Please report this issue to the virtualbox maintainers as a kernel v5.1 interoperability bug.

Thanks,

Bart.