From: Boris Ostrovsky Date: Thu, 14 Mar 2013 21:10:41 +0000 (-0400) Subject: x86, MCE, AMD: Use MCG_CAP MSR to find out number of banks on AMD X-Git-Url: http://git.efficios.com/?a=commitdiff_plain;h=bafcdd3b6cb86035cdb0511450961edcdc084c27;p=deliverable%2Flinux.git x86, MCE, AMD: Use MCG_CAP MSR to find out number of banks on AMD Currently number of error reporting register banks is hardcoded to 6 on AMD processors. This may break in virtualized scenarios when a hypervisor prefers to report fewer banks than what the physical HW provides. Since number of supported banks is reported in MSR_IA32_MCG_CAP[7:0] that's what we should use. Signed-off-by: Boris Ostrovsky Link: http://lkml.kernel.org/r/1363295441-1859-3-git-send-email-boris.ostrovsky@oracle.com [ reverse NULL ptr test logic ] Signed-off-by: Borislav Petkov --- diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c index e3d81a8d646b..9cb52767999a 100644 --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -33,7 +33,6 @@ #include #include -#define NR_BANKS 6 #define NR_BLOCKS 9 #define THRESHOLD_MAX 0xFFF #define INT_TYPE_APIC 0x00020000 @@ -57,7 +56,7 @@ static const char * const th_names[] = { "execution_unit", }; -static DEFINE_PER_CPU(struct threshold_bank * [NR_BANKS], threshold_banks); +static DEFINE_PER_CPU(struct threshold_bank **, threshold_banks); static DEFINE_PER_CPU(unsigned char, bank_map); /* see which banks are on */ static void amd_threshold_interrupt(void); @@ -215,7 +214,7 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c) unsigned int bank, block; int offset = -1; - for (bank = 0; bank < NR_BANKS; ++bank) { + for (bank = 0; bank < mca_cfg.banks; ++bank) { for (block = 0; block < NR_BLOCKS; ++block) { if (block == 0) address = MSR_IA32_MC0_MISC + bank * 4; @@ -277,7 +276,7 @@ static void amd_threshold_interrupt(void) mce_setup(&m); /* assume first bank caused it */ - for (bank = 0; bank < NR_BANKS; ++bank) { + for (bank = 0; bank < mca_cfg.banks; ++bank) { if (!(per_cpu(bank_map, m.cpu) & (1 << bank))) continue; for (block = 0; block < NR_BLOCKS; ++block) { @@ -468,7 +467,7 @@ static __cpuinit int allocate_threshold_blocks(unsigned int cpu, u32 low, high; int err; - if ((bank >= NR_BANKS) || (block >= NR_BLOCKS)) + if ((bank >= mca_cfg.banks) || (block >= NR_BLOCKS)) return 0; if (rdmsr_safe_on_cpu(cpu, address, &low, &high)) @@ -636,9 +635,17 @@ static __cpuinit int threshold_create_bank(unsigned int cpu, unsigned int bank) static __cpuinit int threshold_create_device(unsigned int cpu) { unsigned int bank; + struct threshold_bank **bp; int err = 0; - for (bank = 0; bank < NR_BANKS; ++bank) { + bp = kzalloc(sizeof(struct threshold_bank *) * mca_cfg.banks, + GFP_KERNEL); + if (!bp) + return -ENOMEM; + + per_cpu(threshold_banks, cpu) = bp; + + for (bank = 0; bank < mca_cfg.banks; ++bank) { if (!(per_cpu(bank_map, cpu) & (1 << bank))) continue; err = threshold_create_bank(cpu, bank); @@ -720,11 +727,12 @@ static void threshold_remove_device(unsigned int cpu) { unsigned int bank; - for (bank = 0; bank < NR_BANKS; ++bank) { + for (bank = 0; bank < mca_cfg.banks; ++bank) { if (!(per_cpu(bank_map, cpu) & (1 << bank))) continue; threshold_remove_bank(cpu, bank); } + kfree(per_cpu(threshold_banks, cpu)); } /* get notified when a cpu comes on/off */