Update from: https://bugzilla.kernel.org/show_bug.cgi?id=109051
Apparently Intel has released a PDF which explains a hardware bug: Quote: > VLP52. EOI Transactions May Not be Sent if Software Enters > Core C6 During an Interrupt Service Routine > > Problem: If core C6 is entered after the start of an interrupt > service routine but before a write to the APIC EOI (End of Interrupt) > register, and the core is woken up by an event other than a fixed > interrupt source the core may drop the EOI transaction the next time > APIC EOI register is written and further interrupts from the same or > lower priority level will be blocked. > > Implication: EOI transactions may be lost and interrupts may be blocked > when core C6 is used during interrupt service routines. > > Workaround: It is possible for the firmware to contain a workaround for this > erratum. > > Status: For the steppings affected, see “Summary Table of Changes”." Sources: http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/pentium-n3520-j2850-celeron-n2920-n2820-n2815-n2806-j1850-j1750-spec-update.pdf https://bugzilla.kernel.org/show_bug.cgi?id=109051#c425 Meanwhile, someone has created a script for it which seems to work around the problem, see: https://bugzilla.kernel.org/show_bug.cgi?id=109051#c437 Could this please be implemented into Ubuntu 16.10? Regards -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1575467 Title: [Dell Inspiron 3451] WARNING: CPU: 1 PID: 1297 at /build/linux-lts- utopic-vy2yyy/linux-lts- utopic-3.16.0/drivers/gpu/drm/i915/intel_display.c:1743 vlv_wait_port_ready+0x126/0x170 [i915]() To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1575467/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
