Commit 7559e13f authored May 06, 2015 by Aravind Gopalakrishnan Committed by Borislav Petkov May 06, 2015

x86/mce: Add support for deferred errors on AMD



Deferred errors indicate error conditions that were not corrected, but
those errors have not been consumed yet. They require no action from
S/W (or action is optional). These errors provide info about a latent
uncorrectable MCE that can occur when a poisoned data is consumed by the
processor.

Newer AMD processors can generate deferred errors and can be configured
to generate APIC interrupts on such events.

SUCCOR stands for S/W UnCorrectable error COntainment and Recovery.
It indicates support for data poisoning in HW and deferred error
interrupts.

Add new bitfield to mce_vendor_flags for this. We use this to verify
presence of deferred error interrupts before we enable them in mce_amd.c

While at it, clarify comments in mce_vendor_flags to provide an
indication of usages of the bitfields.

Signed-off-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: x86-ml <x86@kernel.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1430913538-1415-4-git-send-email-Aravind.Gopalakrishnan@amd.com


[ beef up commit message, do CPUID(8000_0007) only once. ]
Signed-off-by: Borislav Petkov <bp@suse.de>

parent 6e6e746e

arch/x86/include/asm/mce.h

+13 −2

Original line number	Diff line number	Diff line
		@@ -117,8 +117,19 @@ struct mca_config {
		};

		struct mce_vendor_flags {
		__u64 overflow_recov : 1, /* cpuid_ebx(80000007) */
		__reserved_0 : 63;
		/*
		* overflow recovery cpuid bit indicates that overflow
		* conditions are not fatal
		*/
		__u64 overflow_recov : 1,

		/*
		* SUCCOR stands for S/W UnCorrectable error COntainment
		* and Recovery. It indicates support for data poisoning
		* in HW and deferred error interrupts.
		*/
		succor : 1,
		__reserved_0 : 62;
		};
		extern struct mce_vendor_flags mce_flags;

arch/x86/kernel/cpu/mcheck/mce.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -1637,10 +1637,16 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
		mce_intel_feature_init(c);
		mce_adjust_timer = cmci_intel_adjust_timer;
		break;
		case X86_VENDOR_AMD:

		case X86_VENDOR_AMD: {
		u32 ebx = cpuid_ebx(0x80000007);

		mce_amd_feature_init(c);
		mce_flags.overflow_recov = cpuid_ebx(0x80000007) & 0x1;
		mce_flags.overflow_recov = !!(ebx & BIT(0));
		mce_flags.succor = !!(ebx & BIT(1));
		break;
		}

		default:
		break;
		}