Message ID | 201501212056.ACF39099.FLVMFOHOSQtFOJ@I-love.SAKURA.ne.jp (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
hi I've encountered [BUG: unable to handle kernel NULL pointer dereference at] which has call stack like your pattern2. And before this happended, I got a lot of memory allocation failure warnings. And my kernel is 3.10.0-327.62.1.el7.x86_64. Since, you mentioned it may be a bug of drm/tmm. So, I checked drm/ttm for possible patch to fix this problem, but found nothing. Could you please tell me is there any progress of this problem that you detected. Best wished! Jinxiang, Gu
On 2020/07/14 18:13, Gu Jinxiang wrote: > I've encountered [BUG: unable to handle kernel NULL pointer dereference at] which has call stack like your pattern2. > And before this happended, I got a lot of memory allocation failure warnings. > And my kernel is 3.10.0-327.62.1.el7.x86_64. > > Since, you mentioned it may be a bug of drm/tmm. So, I checked drm/ttm for possible patch to fix this problem, but found nothing. > Could you please tell me is there any progress of this problem that you detected. I'm not aware of any progress on https://patchwork.kernel.org/patch/5681611/ .
On Wed, 15 Jul 2020 at 17:00, Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote: > > On 2020/07/14 18:13, Gu Jinxiang wrote: > > I've encountered [BUG: unable to handle kernel NULL pointer dereference at] which has call stack like your pattern2. > > And before this happended, I got a lot of memory allocation failure warnings. > > And my kernel is 3.10.0-327.62.1.el7.x86_64. > > > > Since, you mentioned it may be a bug of drm/tmm. So, I checked drm/ttm for possible patch to fix this problem, but found nothing. > > Could you please tell me is there any progress of this problem that you detected. > > I'm not aware of any progress on https://patchwork.kernel.org/patch/5681611/ . Just found this email, I've hopefully fix this issue in my drm-next tree with https://patchwork.freedesktop.org/patch/380782/ Dave.
--- a/drivers/gpu/drm/ttm/ttm_tt.c +++ b/drivers/gpu/drm/ttm/ttm_tt.c @@ -199,8 +199,8 @@ int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev, ttm_tt_alloc_page_directory(ttm); if (!ttm->pages) { - ttm_tt_destroy(ttm); - pr_err("Failed allocating page table\n"); + //ttm_tt_destroy(ttm); + pr_err("Failed allocating page table, but skip ttm_tt_destroy()\n"); return -ENOMEM; } return 0;