tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
x86/ioapic: Correct the PCI/ISA trigger type selection
PCI's default trigger type is level and ISA's is edge. The recent
refactoring made it the other way round, which went unnoticed as it seems
only to cause havoc on some AMD systems.
Make the comment and code do the right thing again.
Fixes: a27dca645d2c ("x86/io_apic: Cleanup trigger/polarity helpers")
Reported-by: Tom Lendacky <thomas.lendacky@amd.com>
Reported-by: Borislav Petkov <bp@alien8.de>
Reported-by: Qian Cai <cai@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lore.kernel.org/r/87d00lgu13.fsf@nanos.tec.linutronix.de
+2
-2
+2
-2
arch/x86/kernel/apic/io_apic.c
+2
-2
arch/x86/kernel/apic/io_apic.c
···
809
809
case MP_IRQTRIG_DEFAULT:
810
810
/*
811
811
* Conforms to spec, ie. bus-type dependent trigger
812
-
* mode. PCI defaults to egde, ISA to level.
812
+
* mode. PCI defaults to level, ISA to edge.
813
813
*/
814
-
level = test_bit(bus, mp_bus_not_pci);
814
+
level = !test_bit(bus, mp_bus_not_pci);
815
815
/* Take EISA into account */
816
816
return eisa_irq_is_level(idx, bus, level);
817
817
case MP_IRQTRIG_EDGE: