On Tue, 2 Feb 2016, John D. Baker wrote: > the display freezes for a couple of minutes shortly after starting X > following a reboot--usually a couple of minutes after logging in via > 'xdm'. I then see the following in 'dmesg' and XConsole. It seems only > to occur once. If it happened more than once in a session, it's been > too long ago for me to remember. > > drm: stuck on render ring > drm: GPU HANG: ecode 0:0x3c8160c1, reason: Ring hung, action: reset > drm: GPU hangs can indicate a bug anywhere in the entire gfx stack, including > userspace. > drm: Please file a _new_ bug report on bugs.freedesktop.org against DRI -> > DRM/Intel > drm: drm/i915 developers can then reassign to the right component if it's not > a kernel issue. > drm: The gpu crash dump is required to analyze gpu hangs, so please always > attach it. > drm: GPU crash dump saved to /sys/class/drm/card0/error > DRM error in i915_reset: Failed to reset chip: -19 > > After this, it seems to operate normally essentially indefinitely.
I think after this, it is not any longer using the DRM (KMS?) magic code so it won't happen again. I also see this GPU hang on a T60; from my dmesg agp0 at pchb0: i915-family chipset i915drmkms0 at pci0 dev 2 function 0: vendor 8086 product 27a2 (rev. 0x03) drm: Memory usable by graphics device = 256M drm: Supports vblank timestamp caching Rev 2 (21.10.2013). drm: Driver supports precise vblank timestamp query. i915drmkms0: interrupting at ioapic0 pin 16 (i915) drm: initialized overlay support intelfb0 at i915drmkms0 i915drmkms0: info: registered panic notifier intelfb0: framebuffer at 0xdb1b9000, size 1400x1050, depth 32, stride 5632 wsdisplay0 at intelfb0 kbdmux 1: console (default, vt100 emulation), using wskbd0 wsmux1: connecting to wsdisplay0 vendor 8086 product 27a6 (miscellaneous display, revision 0x03) at pci0 dev 2 function 1 not configured and then a very short time after or during boot, I usually see DRM error in i915_irq_handler: pipe A underrun though I have done nothing about this - I run with the intel_old driver instead, which works seemingly well enough. iain
