| Summary: | nouveau bug crashes kernel 4.4.6 on warm boot | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Product: | xorg | Reporter: | Michael Daum <mic.daum> | ||||||
| Component: | Driver/nouveau | Assignee: | Nouveau Project <nouveau> | ||||||
| Status: | RESOLVED MOVED | QA Contact: | Xorg Project Team <xorg-team> | ||||||
| Severity: | normal | ||||||||
| Priority: | medium | ||||||||
| Version: | unspecified | ||||||||
| Hardware: | Other | ||||||||
| OS: | All | ||||||||
| Whiteboard: | |||||||||
| i915 platform: | i915 features: | ||||||||
| Attachments: |
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Created attachment 122685 [details]
dump of the nv50_disp_intr_supervisor function
0x80c (2060) looks like this:
0xffffffff814daf32 <+2050>: xor %edx,%edx
0xffffffff814daf34 <+2052>: mov %rax,%rdi
0xffffffff814daf37 <+2055>: mov $0xc,%eax
0xffffffff814daf3c <+2060>: divl -0x88(%rbp)
which has gotta come from
nv50_disp_intr_unk20_2_dp(...) {
u32 dpctrl = nvkm_rd32(device, 0x61c10c + loff);
link_nr = hweight32(dpctrl & 0x000f0000);
...
value = value - (3 * !!(dpctrl & 0x00004000)) - (12 / link_nr);
Which means that on boot link_nr is 0. Michael, if you're up for some kernel patching, can you just add a
if (!link_nr) {
nvkm_error(subdev, "link_nr = 0; dpctrl: %08x\n", dpctrl);
return;
}
right after the link_nr assignment in that function?
The patch from Ilia prevents the kernel from crashing. Reboot does not fail any longer. Additionally _most_ of the time both monitors come up at reboot. But on some reboots one of the monitors stays black and the kernel logs following error (from dmesg): [ 0.955154] nouveau 0000:01:00.0: disp: outp 04:0006:0384: link training failed [ 0.973972] nouveau 0000:01:00.0: disp: outp 04:0006:0384: link training failed [ 0.974279] nouveau 0000:01:00.0: disp: link_nr = 0; dpctrl: 00401101 The value of dpctrl is always the same (00401101) then. -- GitLab Migration Automatic Message -- This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity. You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/xorg/driver/xf86-video-nouveau/issues/259. |
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Created attachment 122684 [details] picture from stack trace taken with camera Whenever doing a warm boot (reboot), kernel 4.4.6 crashes showing the stack trace in the attached picture. The kernel boots fine when doing a cold start or after pressing the reset button. The GPU in question is a "PNY Quadro FX 580" (Tesla / G96) with two attached monitors, both connected on display port. The crash happens quite early when the kernel sets mode on the framebuffer. Resolution is set to 1920x1200 px, 240x75 cols/lines. attached: picture of the screen showing the stack trace dump of "nv50_disp_intr_supervisor" function from the 4.4.6 vmlinux