From 048a8774ca43488d78605031f11cc206d7a2682a Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Fri, 22 Jan 2010 16:01:07 +0100 Subject: [PATCH] x86, cacheinfo: Calculate L3 indices We need to know the valid L3 indices interval when disabling them over /sysfs. Do that when the core is brought online and add boundary checks to the sysfs .store attribute. Signed-off-by: Borislav Petkov LKML-Reference: <1264172467-25155-6-git-send-email-bp@amd64.org> Signed-off-by: H. Peter Anvin --- arch/x86/kernel/cpu/intel_cacheinfo.c | 35 ++++++++++++++++++++++++--- 1 file changed, 31 insertions(+), 4 deletions(-) diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c index 3976ce95095..589b705e80e 100644 --- a/arch/x86/kernel/cpu/intel_cacheinfo.c +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c @@ -151,7 +151,8 @@ struct _cpuid4_info { union _cpuid4_leaf_ebx ebx; union _cpuid4_leaf_ecx ecx; unsigned long size; - unsigned long can_disable; + bool can_disable; + unsigned int l3_indices; DECLARE_BITMAP(shared_cpu_map, NR_CPUS); }; @@ -161,7 +162,8 @@ struct _cpuid4_info_regs { union _cpuid4_leaf_ebx ebx; union _cpuid4_leaf_ecx ecx; unsigned long size; - unsigned long can_disable; + bool can_disable; + unsigned int l3_indices; }; unsigned short num_cache_leaves; @@ -291,6 +293,29 @@ amd_cpuid4(int leaf, union _cpuid4_leaf_eax *eax, (ebx->split.ways_of_associativity + 1) - 1; } +static unsigned int __cpuinit amd_calc_l3_indices(void) +{ + /* + * We're called over smp_call_function_single() and therefore + * are on the correct cpu. + */ + int cpu = smp_processor_id(); + int node = cpu_to_node(cpu); + struct pci_dev *dev = node_to_k8_nb_misc(node); + unsigned int sc0, sc1, sc2, sc3; + u32 val; + + pci_read_config_dword(dev, 0x1C4, &val); + + /* calculate subcache sizes */ + sc0 = !(val & BIT(0)); + sc1 = !(val & BIT(4)); + sc2 = !(val & BIT(8)) + !(val & BIT(9)); + sc3 = !(val & BIT(12)) + !(val & BIT(13)); + + return (max(max(max(sc0, sc1), sc2), sc3) << 10) - 1; +} + static void __cpuinit amd_check_l3_disable(int index, struct _cpuid4_info_regs *this_leaf) { @@ -306,7 +331,8 @@ amd_check_l3_disable(int index, struct _cpuid4_info_regs *this_leaf) (boot_cpu_data.x86_mask < 0x1))) return; - this_leaf->can_disable = 1; + this_leaf->can_disable = true; + this_leaf->l3_indices = amd_calc_l3_indices(); } static int @@ -765,7 +791,8 @@ static ssize_t store_cache_disable(struct _cpuid4_info *this_leaf, return -EINVAL; /* do not allow writes outside of allowed bits */ - if (val & ~(SUBCACHE_MASK | SUBCACHE_INDEX)) + if ((val & ~(SUBCACHE_MASK | SUBCACHE_INDEX)) || + ((val & SUBCACHE_INDEX) > this_leaf->l3_indices)) return -EINVAL; val |= BIT(30); -- 2.39.3