diagnosing freezes (DRI?)

[John Baldwin]

[ moved to current@ ]

On Wednesday 15 April 2009 11:58:38 pm deeptech71 at gmail.com wrote:
> I can reliably (~40%) reproduce a freeze, which I think is related.
> 
> Using the GENERIC debug kernel built from SVN HEAD:
> 
> # cd /usr/obj/usr/src/sys/GENERIC/
> # kgdb kernel.debug /var/crash/vmcore.0
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[ snipped lots of stuff ]

> Kernel page fault with the following non-sleepable locks held: 
> 
> exclusive sleep mutex drmdev (drmdev) r = 0 (0xc373f860) locked @ 
> /usr/src/sys/modules/drm/drm/../../../dev/drm/drm_drv.c:777 
> 
> KDB: stack backtrace: 
> 
> calltrap() at calltrap+0x6 
> 
> --- trap 0xc, eip = 0xc0b611b6, esp = 0xd67d4a98, ebp = 0xd67d4b48 --- 
> 
> slow_copyin(c373f800,c4103300,c42e64e0,d67d4b64,0,...) at 
> slow_copyin+0x6
> radeon_cp_texture(c373f800,c42e64e0,c4103300,309,c0c26218,...) at 
> radeon_cp_texture+0x199 
> 
> drm_ioctl(c39d4e00,c018644e,c42e64e0,3,c40afaf0,...) at drm_ioctl+0x356 
> 

The drm code is doing a copyin() while holding a mutex (which is not allowed).

-- 
John Baldwin