From 26ab12bb9d96133b7880141d68b5e01a8783de9d Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Tue, 1 Dec 2020 16:45:10 -0800 Subject: iommu/hyper-v: Remove I/O-APIC ID check from hyperv_irq_remapping_select() commit a491bb19f728 ("iommu/hyper-v: Implement select() method on remapping irqdomain") restricted the irq_domain_ops::select() callback to match on I/O-APIC index 0, which was correct until the parameter was changed to carry the I/O APIC ID in commit f36a74b9345a. If the ID is not 0 then the match fails. Therefore I/O-APIC init fails to retrieve the parent irqdomain for the I/O-APIC resulting in a boot panic: kernel BUG at arch/x86/kernel/apic/io_apic.c:2408! Fix it by matching the I/O-APIC independent of the ID as there is only one I/O APIC emulated by Hyper-V. [ tglx: Amended changelog ] Fixes: f36a74b9345a ("x86/ioapic: Use I/O-APIC ID for finding irqdomain, not index") Signed-off-by: Dexuan Cui Signed-off-by: Thomas Gleixner Reviewed-by: David Woodhouse Link: https://lore.kernel.org/r/20201202004510.1818-1-decui@microsoft.com --- drivers/iommu/hyperv-iommu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/iommu') diff --git a/drivers/iommu/hyperv-iommu.c b/drivers/iommu/hyperv-iommu.c index 9438daa24fdb..1d21a0b5f724 100644 --- a/drivers/iommu/hyperv-iommu.c +++ b/drivers/iommu/hyperv-iommu.c @@ -105,8 +105,8 @@ static int hyperv_irq_remapping_select(struct irq_domain *d, struct irq_fwspec *fwspec, enum irq_domain_bus_token bus_token) { - /* Claim only the first (and only) I/OAPIC */ - return x86_fwspec_is_ioapic(fwspec) && fwspec->param[0] == 0; + /* Claim the only I/O APIC emulated by Hyper-V */ + return x86_fwspec_is_ioapic(fwspec); } static const struct irq_domain_ops hyperv_ir_domain_ops = { -- cgit v1.2.3