[077/139] x86, cacheinfo: Fix disabling of L3 cache indices
in [Kernel]
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From: Greg KH on 22 Apr 2010 16:20 2.6.33-stable review patch. If anyone has any objections, please let us know. ------------------ From: Borislav Petkov <borislav.petkov(a)amd.com> commit dcf39daf3d6d97f8741e82f0b9fb7554704ed2d1 upstream. * Correct the masks used for writing the cache index disable indices. * Do not turn off L3 scrubber - it is not necessary. * Make sure wbinvd is executed on the same node where the L3 is. * Check for out-of-bounds values written to the registers. * Make show_cache_disable hex values unambiguous * Check for Erratum #388 Signed-off-by: Borislav Petkov <borislav.petkov(a)amd.com> LKML-Reference: <1264172467-25155-4-git-send-email-bp(a)amd64.org> Signed-off-by: H. Peter Anvin <hpa(a)zytor.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de> --- arch/x86/kernel/cpu/intel_cacheinfo.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) --- a/arch/x86/kernel/cpu/intel_cacheinfo.c +++ b/arch/x86/kernel/cpu/intel_cacheinfo.c @@ -18,6 +18,7 @@ #include <asm/processor.h> #include <linux/smp.h> #include <asm/k8.h> +#include <asm/smp.h> #define LVL_1_INST 1 #define LVL_1_DATA 2 @@ -299,8 +300,10 @@ amd_check_l3_disable(int index, struct _ if (boot_cpu_data.x86 == 0x11) return; - /* see erratum #382 */ - if ((boot_cpu_data.x86 == 0x10) && (boot_cpu_data.x86_model < 0x8)) + /* see errata #382 and #388 */ + if ((boot_cpu_data.x86 == 0x10) && + ((boot_cpu_data.x86_model < 0x9) || + (boot_cpu_data.x86_mask < 0x1))) return; this_leaf->can_disable = 1; @@ -726,12 +729,12 @@ static ssize_t show_cache_disable(struct return -EINVAL; pci_read_config_dword(dev, 0x1BC + index * 4, ®); - return sprintf(buf, "%x\n", reg); + return sprintf(buf, "0x%08x\n", reg); } #define SHOW_CACHE_DISABLE(index) \ static ssize_t \ -show_cache_disable_##index(struct _cpuid4_info *this_leaf, char *buf) \ +show_cache_disable_##index(struct _cpuid4_info *this_leaf, char *buf) \ { \ return show_cache_disable(this_leaf, buf, index); \ } @@ -745,7 +748,9 @@ static ssize_t store_cache_disable(struc int node = cpu_to_node(cpu); struct pci_dev *dev = node_to_k8_nb_misc(node); unsigned long val = 0; - unsigned int scrubber = 0; + +#define SUBCACHE_MASK (3UL << 20) +#define SUBCACHE_INDEX 0xfff if (!this_leaf->can_disable) return -EINVAL; @@ -759,21 +764,24 @@ static ssize_t store_cache_disable(struc if (strict_strtoul(buf, 10, &val) < 0) return -EINVAL; - val |= 0xc0000000; - - pci_read_config_dword(dev, 0x58, &scrubber); - scrubber &= ~0x1f000000; - pci_write_config_dword(dev, 0x58, scrubber); + /* do not allow writes outside of allowed bits */ + if (val & ~(SUBCACHE_MASK | SUBCACHE_INDEX)) + return -EINVAL; - pci_write_config_dword(dev, 0x1BC + index * 4, val & ~0x40000000); - wbinvd(); + val |= BIT(30); pci_write_config_dword(dev, 0x1BC + index * 4, val); + /* + * We need to WBINVD on a core on the node containing the L3 cache which + * indices we disable therefore a simple wbinvd() is not sufficient. + */ + wbinvd_on_cpu(cpu); + pci_write_config_dword(dev, 0x1BC + index * 4, val | BIT(31)); return count; } #define STORE_CACHE_DISABLE(index) \ static ssize_t \ -store_cache_disable_##index(struct _cpuid4_info *this_leaf, \ +store_cache_disable_##index(struct _cpuid4_info *this_leaf, \ const char *buf, size_t count) \ { \ return store_cache_disable(this_leaf, buf, count, index); \ -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |