| Summary: | [all bisected]system hang and BUG: unable to handle kernel NULL pointer dereference at 0000000000000084 when kill X | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Product: | DRI | Reporter: | lu hua <huax.lu> | ||||||
| Component: | DRM/Intel | Assignee: | Matt Roper <matthew.d.roper> | ||||||
| Status: | CLOSED FIXED | QA Contact: | Intel GFX Bugs mailing list <intel-gfx-bugs> | ||||||
| Severity: | critical | ||||||||
| Priority: | high | CC: | eero.t.tamminen, intel-gfx-bugs, michael, przanoni | ||||||
| Version: | unspecified | ||||||||
| Hardware: | All | ||||||||
| OS: | Linux (All) | ||||||||
| Whiteboard: | |||||||||
| i915 platform: | i915 features: | ||||||||
| Attachments: |
|
||||||||
|
Description
lu hua
2015-03-02 05:47:51 UTC
Created attachment 113905 [details]
Xorg.0.log
output:
root@x-bdw05:~# pkill X
root@x-bdw05:~# xterm: fatal IO error 11 (Resource temporarily unavailable) or KillClient on X server ":0"
xinit: connection to X server lost
waiting for X server to shut down ..........
xinit: X server slow to shut down, sending KILL signal
waiting for server to die
Can you please bisect this? Bisect shows: fd2d61341bf39d1054256c07d6eddd624ebc4241 is the first bad commit commit fd2d61341bf39d1054256c07d6eddd624ebc4241 Author: Matt Roper <matthew.d.roper@intel.com> AuthorDate: Fri Feb 27 10:12:01 2015 -0800 Commit: Daniel Vetter <daniel.vetter@ffwll.ch> CommitDate: Fri Feb 27 19:56:17 2015 +0100 drm/i915: Use plane->state->fb in watermark code (v2) plane->fb is a legacy pointer that not always be up-to-date (or updated early enough). Make sure the watermark code uses plane->state->fb so that we're always doing our calculations based on the correct framebuffers. This patch was generated by Coccinelle with the following semantic patch: @@ struct drm_plane *P; @@ - P->fb + P->state->fb v2: Rebase Signed-off-by: Matt Roper <matthew.d.roper@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Revert this commit, this issue goes away. Should be fixed by the revert of that patch that Daniel pushed today. Can you verify? I get a very similar crash to this on BDW hardware when modeswitching; changing to console results in an oops in the same function. gdb claims the IP was in the line changed in fd2d613, p->pri.bytes_per_pixel = crtc->primary->state->fb->bits_per_pixel / 8; so I suspect it's the same bug with a different trigger. If I revert the patch, I am able to change to console without a crash, though the mode in the console is not correct and causes the text to flicker in three locations. I believe this should be fixed by these two patches: http://patchwork.freedesktop.org/patch/43919/ http://patchwork.freedesktop.org/patch/43920/ (In reply to Matt Roper from comment #6) > I believe this should be fixed by these two patches: > > http://patchwork.freedesktop.org/patch/43919/ > http://patchwork.freedesktop.org/patch/43920/ Test on the latest -nightly kernel(commit a5217f77503a1089ae 2015y-03m-03d-08h-25m-29s) without these 2 patches, this issue still exists. Apply these 2 patches on commit a5217f77503a1089ae, it works well. Hello Matt, Would you pls help merge up your patches for this bug? (In reply to wendy.wang from comment #8) > Hello Matt, > Would you pls help merge up your patches for this bug? We actually reworked the patches a bit, but Daniel just merged the last one this morning, so I think this should be fixed upstream; moving status to 'resolved.' Please reopen this defect if you still see the bug on latest di-nightly. Test on the latest -nightly kernel. It works well. Closing old verified. |
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.