On 2/26/2018 10:31 AM, Borislav Petkov wrote: > On Mon, Feb 26, 2018 at 10:14:10AM -0600, Tom Lendacky wrote: >> On 2/24/2018 2:59 AM, Thomas Gleixner wrote: >>> On Sat, 24 Feb 2018, Paul Menzel wrote: >>>> Am 23.02.2018 um 20:09 schrieb Borislav Petkov: >>>>> On Fri, Feb 23, 2018 at 07:18:34PM +0100, Thomas Gleixner wrote: >>>>>> Borislav is seeing similar issues on larger AMD machines. The interrupt >>>>>> seems to come from BIOS/microcode during bringup of secondary CPUs and we >>>>>> have no idea why. >>>>> >>>>> Paul, can you boot 4.14 and grep your dmesg for something like: >>>>> >>>>> [ 0.000000] spurious 8259A interrupt: IRQ7. > >>>>> ? >>>> >>>> No, I do not see that. Please find the logs attached. >>> >>> From your 4.14 log: >>> >>> Feb 19 09:48:06.843173 kodi kernel: CPU 0 irqstacks, hard=e9b0a000 >>> soft=e9b0c000 >>> Feb 19 09:48:06.843216 kodi kernel: spurious 8259A interrupt: IRQ7. >> >> I think I remember seeing something like this previously and it turned out >> to be a BIOS bug. All the AP's were enabled to work with the legacy 8259 >> interrupt controller. In an SMP system, only one processor in the system >> should be configured to handle legacy 8259 interrupts (ExtINT delivery >> mode - see Intel's SDM, Volume 3, section 10.5.1, Delivery Mode). Once >> the BIOS was fixed, the spurious interrupt message went away. >> >> I believe at some point during UEFI, the APs were exposed to an ExtINT >> interrupt. Since they were configured to handle ExtINT delivery mode and >> interrupts were not yet enabled, the interrupt was left pending. When the >> APs were started by the OS and interrupts were enabled, the interrupt >> triggered. Since the original pending interrupt was handled by the BSP, >> there was no longer an interrupt actually pending, so the 8259 responds >> with IRQ 7 when queried by the OS. This occurred for each AP. > > Interesting - is this something that can happen on Zen too?
Yes, that's where I remember seeing it. Thanks, Tom > > Because I have such reports too. >
