From 68627a697c195937672ce07683094c72b1174786 Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Wed, 21 Feb 2018 11:18:58 +0100 Subject: [PATCH] x86/mce/AMD, EDAC/mce_amd: Enumerate Reserved SMCA bank type Currently, bank 4 is reserved on Fam17h, so we chose not to initialize bank 4 in the smca_banks array. This means that when we check if a bank is initialized, like during boot or resume, we will see that bank 4 is not initialized and try to initialize it. This will cause a call trace, when resuming from suspend, due to rdmsr_*on_cpu() calls in the init path. The rdmsr_*on_cpu() calls issue an IPI but we're running with interrupts disabled. This triggers: WARNING: CPU: 0 PID: 11523 at kernel/smp.c:291 smp_call_function_single+0xdc/0xe0 ... Reserved banks will be read-as-zero, so their MCA_IPID register will be zero. So, like the smca_banks array, the threshold_banks array will not have an entry for a reserved bank since all its MCA_MISC* registers will be zero. Enumerate a "Reserved" bank type that matches on a HWID_MCATYPE of 0,0. Use the "Reserved" type when checking if a bank is reserved. It's possible that other bank numbers may be reserved on future systems. Don't try to find the block address on reserved banks. Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov Cc: # 4.14.x Cc: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Tony Luck Cc: linux-edac Link: http://lkml.kernel.org/r/20180221101900.10326-7-bp@alien8.de Signed-off-by: Ingo Molnar --- arch/x86/include/asm/mce.h | 1 + arch/x86/kernel/cpu/mcheck/mce_amd.c | 7 +++++++ drivers/edac/mce_amd.c | 11 +++++++---- 3 files changed, 15 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/mce.h b/arch/x86/include/asm/mce.h index c3fb9a792e13..8c7b3e5a2d01 100644 --- a/arch/x86/include/asm/mce.h +++ b/arch/x86/include/asm/mce.h @@ -294,6 +294,7 @@ enum smca_bank_types { SMCA_IF, /* Instruction Fetch */ SMCA_L2_CACHE, /* L2 Cache */ SMCA_DE, /* Decoder Unit */ + SMCA_RESERVED, /* Reserved */ SMCA_EX, /* Execution Unit */ SMCA_FP, /* Floating Point */ SMCA_L3_CACHE, /* L3 Cache */ diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c index 7fbb19cb1859..d8ba9d0c3f01 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -82,6 +82,7 @@ static struct smca_bank_name smca_names[] = { [SMCA_IF] = { "insn_fetch", "Instruction Fetch Unit" }, [SMCA_L2_CACHE] = { "l2_cache", "L2 Cache" }, [SMCA_DE] = { "decode_unit", "Decode Unit" }, + [SMCA_RESERVED] = { "reserved", "Reserved" }, [SMCA_EX] = { "execution_unit", "Execution Unit" }, [SMCA_FP] = { "floating_point", "Floating Point Unit" }, [SMCA_L3_CACHE] = { "l3_cache", "L3 Cache" }, @@ -127,6 +128,9 @@ static enum smca_bank_types smca_get_bank_type(unsigned int bank) static struct smca_hwid smca_hwid_mcatypes[] = { /* { bank_type, hwid_mcatype, xec_bitmap } */ + /* Reserved type */ + { SMCA_RESERVED, HWID_MCATYPE(0x00, 0x0), 0x0 }, + /* ZN Core (HWID=0xB0) MCA types */ { SMCA_LS, HWID_MCATYPE(0xB0, 0x0), 0x1FFFEF }, { SMCA_IF, HWID_MCATYPE(0xB0, 0x1), 0x3FFF }, @@ -433,6 +437,9 @@ static u32 get_block_address(unsigned int cpu, u32 current_addr, u32 low, u32 hi u32 addr = 0, offset = 0; if (mce_flags.smca) { + if (smca_get_bank_type(bank) == SMCA_RESERVED) + return addr; + if (!block) { addr = MSR_AMD64_SMCA_MCx_MISC(bank); } else { diff --git a/drivers/edac/mce_amd.c b/drivers/edac/mce_amd.c index a11a671c7a38..2ab4d61ee47e 100644 --- a/drivers/edac/mce_amd.c +++ b/drivers/edac/mce_amd.c @@ -854,21 +854,24 @@ static void decode_mc6_mce(struct mce *m) static void decode_smca_error(struct mce *m) { struct smca_hwid *hwid; - unsigned int bank_type; + enum smca_bank_types bank_type; const char *ip_name; u8 xec = XEC(m->status, xec_mask); if (m->bank >= ARRAY_SIZE(smca_banks)) return; - if (x86_family(m->cpuid) >= 0x17 && m->bank == 4) - pr_emerg(HW_ERR "Bank 4 is reserved on Fam17h.\n"); - hwid = smca_banks[m->bank].hwid; if (!hwid) return; bank_type = hwid->bank_type; + + if (bank_type == SMCA_RESERVED) { + pr_emerg(HW_ERR "Bank %d is reserved.\n", m->bank); + return; + } + ip_name = smca_get_long_name(bank_type); pr_emerg(HW_ERR "%s Extended Error Code: %d\n", ip_name, xec);