Commit 0f3922a9 authored Dec 08, 2017 by Jan Beulich Committed by Boris Ostrovsky Dec 12, 2017

x86/Xen: don't report ancient LAPIC version

Unconditionally reporting a value seen on the P4 or older invokes
functionality like io_apic_get_unique_id() on 32-bit builds, resulting
in a panic() with sufficiently many CPUs and/or IO-APICs. Doing what
that function does would be the hypervisor's responsibility anyway, so
makes no sense to be used when running on Xen. Uniformly report a more
modern version; this shouldn't matter much as both LAPIC and IO-APIC are
being managed entirely / mostly by the hypervisor.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>

parent 1ab134ca

arch/x86/xen/apic.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -56,7 +56,7 @@ static u32 xen_apic_read(u32 reg)
		return 0;

		if (reg == APIC_LVR)
		return 0x10;
		return 0x14;
		#ifdef CONFIG_X86_32
		if (reg == APIC_LDR)
		return SET_APIC_LOGICAL_ID(1UL << smp_processor_id());

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