On Jan 21, 2021, at 9:47 AM, Thomas Zimmermann tzimmermann@suse.de wrote:
(cc'ing dri-devel)
Hi,
thanks for reporting the bug.
Am 21.01.21 um 15:35 schrieb Chuck Lever:
Hi Thomas- I was not able to find an appropriate mailing list entry in MAINTAINERS,
That would be dri-devel@lists.freedesktop.org
so I'm mailing you directly as committer of record for: 43676605f890 ("drm/ttm: Add vmap/vunmap to TTM and TTM GEM helpers") I've noticed that since putting v5.11-rc on my test systems, overnight on an otherwise idle system the load average seems to grow as the result of a kernel worker thread.
Earlier this week I fixed a couple of leaks in that code. Could you please apply the patch at [1] and report back if it fixes the issue.
If it's a separate problem, I'll take a closer look.
Thomas, thank you for your quick response. I've installed your patch on one system and it looks promising already. I'll let it soak overnight.
Best regards Thomas
[1] https://lore.kernel.org/dri-devel/20210118144639.27307-1-tzimmermann@suse.de...
I used "perf top" to see what it had gotten up to, and it appears that it was spending lots of time walking an interval tree on behalf of memtype_reserve(). The most frequently-observed stack trace seems to be: kworker/3:1-2355 [003] 60950.150928: function: memtype_reserve kworker/3:1-2355 [003] 60950.150942: kernel_stack: <stack trace> => ffffffffc0c66083 => memtype_reserve (ffffffffa005f9d5) => __ioremap_caller (ffffffffa005aac1) => ttm_bo_vmap (ffffffffc040f266) => drm_gem_vram_vmap (ffffffffc042c5cd) => drm_gem_vmap (ffffffffc0506a7f) => drm_client_buffer_vmap (ffffffffc0523741) => drm_fb_helper_damage_work (ffffffffc049a34a) => process_one_work (ffffffffa00dd92e) => worker_thread (ffffffffa00dde46) => kthread (ffffffffa00e22c4) => ret_from_fork (ffffffffa0004192) I see a regular call to memtype_reserve(), but never a matching call to memtype_free(), thus I suspect a leak of I/O maps in this code. -- Chuck Lever
-- Thomas Zimmermann Graphics Driver Developer SUSE Software Solutions Germany GmbH Maxfeldstr. 5, 90409 Nürnberg, Germany (HRB 36809, AG Nürnberg) Geschäftsführer: Felix Imendörffer
-- Chuck Lever