From: Boris Ostrovsky <boris.ostrov...@oracle.com> Paravirtual guests are not expected to load microcode into processors and therefore it is not necessary to initialize microcode loading logic.
In fact, under certain circumstances initializing this logic may cause the guest to crash. Specifically, 32-bit kernels use __pa_nodebug() macro which does not work in Xen (the code path that leads to this macro happens during resume when we call mc_bp_resume()->load_ucode_ap() ->check_loader_disabled_ap()) Signed-off-by: Boris Ostrovsky <boris.ostrov...@oracle.com> Link: http://lkml.kernel.org/r/1417469264-31470-1-git-send-email-boris.ostrov...@oracle.com Signed-off-by: Borislav Petkov <b...@suse.de> --- arch/x86/kernel/cpu/microcode/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c index 2ce9051174e6..ebd232d7de4d 100644 --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -557,7 +557,7 @@ static int __init microcode_init(void) struct cpuinfo_x86 *c = &cpu_data(0); int error; - if (dis_ucode_ldr) + if (paravirt_enabled() || dis_ucode_ldr) return 0; if (c->x86_vendor == X86_VENDOR_INTEL) -- 2.0.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
