On Fri, Apr 6, 2012 at 23:31, Jiri Slaby <jslaby@suse...> wrote: >> That was introduced in 05eff845a28499762075d3a72e238a31f4d2407c to close >> a race where the pipestat triggered an interrupt after we processed the >> secondary registers and before reseting the primary. >> >> But the basic premise that we should only enter the interrupt handler >> with IIR!=0 holds (presuming non-shared interrupt lines such as MSI). > > Ok, this behavior is definitely new. I get several "nobody cared" about > this interrupt a week. This never used to happen. And something weird > emerges in /proc/interrupts when this happens: > 42: 1003292 1212890 PCI-MSI-edge �s����:0000:00:02.0 > instead of > 42: 1006715 1218472 PCI-MSI-edge i915@pci:0000:00:02.0
This looks ugly. Can you try to reproduce on 3.4-rc2? That should contain everything that -next currently contains drm/i915-wise. If it still happens there, please bisect it.
Also please check whether any of the subordinate interrupt regs (pipestat) is stuck and might cause these interrupts as Jesse suggested.