From: Tony Luck Date: Fri, 25 May 2018 14:42:09 -0700 Subject: x86/mce: Check for alternate indication of machine check recovery on Skylake Git-commit: 4c5717da1d021cf368eabb3cb1adcaead56c0d1e Patch-mainline: v4.18-rc2 References: bsc#1110006, fate#326230 Currently we just check the "CAPID0" register to see whether the CPU can recover from machine checks. But there are also some special SKUs which do not have all advanced RAS features, but do enable machine check recovery for use with NVDIMMs. Add a check for any of bits {8:5} in the "CAPID5" register (each reports some NVDIMM mode available, if any of them are set, then the system supports memory machine check recovery). Signed-off-by: Tony Luck Signed-off-by: Thomas Gleixner Cc: Qiuxu Zhuo Cc: Ashok Raj Cc: stable@vger.kernel.org # 4.9 Cc: Dan Williams Cc: Borislav Petkov Link: https://lkml.kernel.org/r/03cbed6e99ddafb51c2eadf9a3b7c8d7a0cc204e.1527283897.git.tony.luck@intel.com Acked-by: Borislav Petkov Acked-by: Joerg Roedel --- arch/x86/kernel/quirks.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c index 697a4ce04308..736348ead421 100644 --- a/arch/x86/kernel/quirks.c +++ b/arch/x86/kernel/quirks.c @@ -645,12 +645,19 @@ static void quirk_intel_brickland_xeon_ras_cap(struct pci_dev *pdev) /* Skylake */ static void quirk_intel_purley_xeon_ras_cap(struct pci_dev *pdev) { - u32 capid0; + u32 capid0, capid5; pci_read_config_dword(pdev, 0x84, &capid0); + pci_read_config_dword(pdev, 0x98, &capid5); - if ((capid0 & 0xc0) == 0xc0) + /* + * CAPID0{7:6} indicate whether this is an advanced RAS SKU + * CAPID5{8:5} indicate that various NVDIMM usage modes are + * enabled, so memory machine check recovery is also enabled. + */ + if ((capid0 & 0xc0) == 0xc0 || (capid5 & 0x1e0)) static_branch_inc(&mcsafe_key); + } DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x0ec3, quirk_intel_brickland_xeon_ras_cap); DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2fc0, quirk_intel_brickland_xeon_ras_cap);