x86: don't print a warning when MTRR are blank and running in KVM (4147c874) · Commits · 戴 / test

Inside a KVM virtual machine the MTRRs are usually blank. This confuses Linux and causes a warning message at boot. This patch removes that warning message when running Linux as a KVM guest. Signed-off-by:

Joerg Roedel <joerg.roedel@amd.com> Signed-off-by:

Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/cpu/mtrr/main.c

+6 −2

Original line number	Diff line number	Diff line
		@@ -43,6 +43,7 @@
		#include <asm/uaccess.h>
		#include <asm/processor.h>
		#include <asm/msr.h>
		#include <asm/kvm_para.h>
		#include "mtrr.h"

		u32 num_var_ranges = 0;
		@@ -689,8 +690,11 @@ int __init mtrr_trim_uncached_memory(unsigned long end_pfn)

		/* kvm/qemu doesn't have mtrr set right, don't trim them all */
		if (!highest_pfn) {
		printk(KERN_WARNING "WARNING: strange, CPU MTRRs all blank?\n");
		if (!kvm_para_available()) {
		printk(KERN_WARNING
		"WARNING: strange, CPU MTRRs all blank?\n");
		WARN_ON(1);
		}
		return 0;
		}

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