diff options
| author | Sean V Kelley <sean.v.kelley@linux.intel.com> | 2020-02-20 11:29:29 -0800 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2020-02-27 16:47:28 -0600 |
| commit | b88bf6c3b6ff77948c153cac4e564642b0b90632 (patch) | |
| tree | 920208ad95c067d3b3c402b7e3e12592ea488617 /Documentation/PCI | |
| parent | bb6d3fb354c5ee8d6bde2d576eb7220ea09862b9 (diff) | |
PCI: Add boot interrupt quirk mechanism for Xeon chipsets
The following was observed by Kar Hin Ong with RT patchset:
Backtrace:
irq 19: nobody cared (try booting with the "irqpoll" option)
CPU: 0 PID: 3329 Comm: irq/34-nipalk Tainted:4.14.87-rt49 #1
Hardware name: National Instruments NI PXIe-8880/NI PXIe-8880,
BIOS 2.1.5f1 01/09/2020
Call Trace:
<IRQ>
? dump_stack+0x46/0x5e
? __report_bad_irq+0x2e/0xb0
? note_interrupt+0x242/0x290
? nNIKAL100_memoryRead16+0x8/0x10 [nikal]
? handle_irq_event_percpu+0x55/0x70
? handle_irq_event+0x4f/0x80
? handle_fasteoi_irq+0x81/0x180
? handle_irq+0x1c/0x30
? do_IRQ+0x41/0xd0
? common_interrupt+0x84/0x84
</IRQ>
...
handlers:
[<ffffffffb3297200>] irq_default_primary_handler threaded
[<ffffffffb3669180>] usb_hcd_irq
Disabling IRQ #19
The problem being that this device is triggering boot interrupts
due to threaded interrupt handling and masking of the IO-APIC. These
boot interrupts are then forwarded on to the legacy PCH's PIRQ lines
where there is no handler present for the device.
Whenever a PCI device fires interrupt (INTx) to Pin 20 of IOAPIC 2
(GSI 44), the kernel receives two interrupts:
1. Interrupt from Pin 20 of IOAPIC 2 -> Expected
2. Interrupt from Pin 19 of IOAPIC 1 -> UNEXPECTED
Quirks for disabling boot interrupts (preferred) or rerouting the
handler exist but do not address these Xeon chipsets' mechanism:
https://lore.kernel.org/lkml/12131949181903-git-send-email-sassmann@suse.de/
Add a new mechanism via PCI CFG for those chipsets supporting CIPINTRC
register's dis_intx_rout2ich bit.
Link: https://lore.kernel.org/r/20200220192930.64820-2-sean.v.kelley@linux.intel.com
Reported-by: Kar Hin Ong <kar.hin.ong@ni.com>
Tested-by: Kar Hin Ong <kar.hin.ong@ni.com>
Signed-off-by: Sean V Kelley <sean.v.kelley@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Diffstat (limited to 'Documentation/PCI')
0 files changed, 0 insertions, 0 deletions