Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754577Ab0AEAg1 (ORCPT ); Mon, 4 Jan 2010 19:36:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754563Ab0AEAgV (ORCPT ); Mon, 4 Jan 2010 19:36:21 -0500 Received: from kroah.org ([198.145.64.141]:42487 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754552Ab0AEAgP (ORCPT ); Mon, 4 Jan 2010 19:36:15 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@kernel.org, stable-review@kernel.org Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Borislav Petkov , "H. Peter Anvin" , Mauro Carvalho Chehab , Aristeu Rozanski , Randy Dunlap , Doug Thompson , Greg Kroah-Hartman Subject: [PATCH 88/97] x86, msr: Add support for non-contiguous cpumasks Date: Mon, 4 Jan 2010 16:33:41 -0800 Message-Id: <1262651630-7354-88-git-send-email-gregkh@suse.de> X-Mailer: git-send-email 1.6.6 In-Reply-To: <20100105003133.GA7199@kroah.com> References: <20100105003133.GA7199@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6920 Lines: 246 From: Borislav Petkov commit 505422517d3f126bb939439e9d15dece94e11d2c upstream. The current rd/wrmsr_on_cpus helpers assume that the supplied cpumasks are contiguous. However, there are machines out there like some K8 multinode Opterons which have a non-contiguous core enumeration on each node (e.g. cores 0,2 on node 0 instead of 0,1), see http://www.gossamer-threads.com/lists/linux/kernel/1160268. This patch fixes out-of-bounds writes (see URL above) by adding per-CPU msr structs which are used on the respective cores. Additionally, two helpers, msrs_{alloc,free}, are provided for use by the callers of the MSR accessors. Cc: H. Peter Anvin Cc: Mauro Carvalho Chehab Cc: Aristeu Rozanski Cc: Randy Dunlap Cc: Doug Thompson Signed-off-by: Borislav Petkov LKML-Reference: <20091211171440.GD31998@aftab> Signed-off-by: H. Peter Anvin Signed-off-by: Greg Kroah-Hartman --- arch/x86/include/asm/msr.h | 3 ++ arch/x86/lib/msr.c | 26 +++++++++++++++++++++--- drivers/edac/amd64_edac.c | 46 ++++++++++++++++--------------------------- 3 files changed, 42 insertions(+), 33 deletions(-) diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h index 9a00219..bb30776 100644 --- a/arch/x86/include/asm/msr.h +++ b/arch/x86/include/asm/msr.h @@ -244,6 +244,9 @@ do { \ #define write_rdtscp_aux(val) wrmsr(0xc0000103, (val), 0) +struct msr *msrs_alloc(void); +void msrs_free(struct msr *msrs); + #ifdef CONFIG_SMP int rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h); int wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h); diff --git a/arch/x86/lib/msr.c b/arch/x86/lib/msr.c index 41628b1..8728341 100644 --- a/arch/x86/lib/msr.c +++ b/arch/x86/lib/msr.c @@ -7,7 +7,6 @@ struct msr_info { u32 msr_no; struct msr reg; struct msr *msrs; - int off; int err; }; @@ -18,7 +17,7 @@ static void __rdmsr_on_cpu(void *info) int this_cpu = raw_smp_processor_id(); if (rv->msrs) - reg = &rv->msrs[this_cpu - rv->off]; + reg = per_cpu_ptr(rv->msrs, this_cpu); else reg = &rv->reg; @@ -32,7 +31,7 @@ static void __wrmsr_on_cpu(void *info) int this_cpu = raw_smp_processor_id(); if (rv->msrs) - reg = &rv->msrs[this_cpu - rv->off]; + reg = per_cpu_ptr(rv->msrs, this_cpu); else reg = &rv->reg; @@ -80,7 +79,6 @@ static void __rwmsr_on_cpus(const struct cpumask *mask, u32 msr_no, memset(&rv, 0, sizeof(rv)); - rv.off = cpumask_first(mask); rv.msrs = msrs; rv.msr_no = msr_no; @@ -120,6 +118,26 @@ void wrmsr_on_cpus(const struct cpumask *mask, u32 msr_no, struct msr *msrs) } EXPORT_SYMBOL(wrmsr_on_cpus); +struct msr *msrs_alloc(void) +{ + struct msr *msrs = NULL; + + msrs = alloc_percpu(struct msr); + if (!msrs) { + pr_warning("%s: error allocating msrs\n", __func__); + return NULL; + } + + return msrs; +} +EXPORT_SYMBOL(msrs_alloc); + +void msrs_free(struct msr *msrs) +{ + free_percpu(msrs); +} +EXPORT_SYMBOL(msrs_free); + /* These "safe" variants are slower and should be used when the target MSR may not actually exist. */ static void __rdmsr_safe_on_cpu(void *info) diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c index 6ee408f..d271509 100644 --- a/drivers/edac/amd64_edac.c +++ b/drivers/edac/amd64_edac.c @@ -13,6 +13,8 @@ module_param(report_gart_errors, int, 0644); static int ecc_enable_override; module_param(ecc_enable_override, int, 0644); +static struct msr *msrs; + /* Lookup table for all possible MC control instances */ struct amd64_pvt; static struct mem_ctl_info *mci_lookup[EDAC_MAX_NUMNODES]; @@ -2632,8 +2634,7 @@ static void get_cpus_on_this_dct_cpumask(struct cpumask *mask, int nid) static bool amd64_nb_mce_bank_enabled_on_node(int nid) { cpumask_var_t mask; - struct msr *msrs; - int cpu, nbe, idx = 0; + int cpu, nbe; bool ret = false; if (!zalloc_cpumask_var(&mask, GFP_KERNEL)) { @@ -2644,32 +2645,22 @@ static bool amd64_nb_mce_bank_enabled_on_node(int nid) get_cpus_on_this_dct_cpumask(mask, nid); - msrs = kzalloc(sizeof(struct msr) * cpumask_weight(mask), GFP_KERNEL); - if (!msrs) { - amd64_printk(KERN_WARNING, "%s: error allocating msrs\n", - __func__); - free_cpumask_var(mask); - return false; - } - rdmsr_on_cpus(mask, MSR_IA32_MCG_CTL, msrs); for_each_cpu(cpu, mask) { - nbe = msrs[idx].l & K8_MSR_MCGCTL_NBE; + struct msr *reg = per_cpu_ptr(msrs, cpu); + nbe = reg->l & K8_MSR_MCGCTL_NBE; debugf0("core: %u, MCG_CTL: 0x%llx, NB MSR is %s\n", - cpu, msrs[idx].q, + cpu, reg->q, (nbe ? "enabled" : "disabled")); if (!nbe) goto out; - - idx++; } ret = true; out: - kfree(msrs); free_cpumask_var(mask); return ret; } @@ -2677,8 +2668,7 @@ out: static int amd64_toggle_ecc_err_reporting(struct amd64_pvt *pvt, bool on) { cpumask_var_t cmask; - struct msr *msrs = NULL; - int cpu, idx = 0; + int cpu; if (!zalloc_cpumask_var(&cmask, GFP_KERNEL)) { amd64_printk(KERN_WARNING, "%s: error allocating mask\n", @@ -2688,34 +2678,27 @@ static int amd64_toggle_ecc_err_reporting(struct amd64_pvt *pvt, bool on) get_cpus_on_this_dct_cpumask(cmask, pvt->mc_node_id); - msrs = kzalloc(sizeof(struct msr) * cpumask_weight(cmask), GFP_KERNEL); - if (!msrs) { - amd64_printk(KERN_WARNING, "%s: error allocating msrs\n", - __func__); - return -ENOMEM; - } - rdmsr_on_cpus(cmask, MSR_IA32_MCG_CTL, msrs); for_each_cpu(cpu, cmask) { + struct msr *reg = per_cpu_ptr(msrs, cpu); + if (on) { - if (msrs[idx].l & K8_MSR_MCGCTL_NBE) + if (reg->l & K8_MSR_MCGCTL_NBE) pvt->flags.ecc_report = 1; - msrs[idx].l |= K8_MSR_MCGCTL_NBE; + reg->l |= K8_MSR_MCGCTL_NBE; } else { /* * Turn off ECC reporting only when it was off before */ if (!pvt->flags.ecc_report) - msrs[idx].l &= ~K8_MSR_MCGCTL_NBE; + reg->l &= ~K8_MSR_MCGCTL_NBE; } - idx++; } wrmsr_on_cpus(cmask, MSR_IA32_MCG_CTL, msrs); - kfree(msrs); free_cpumask_var(cmask); return 0; @@ -3193,6 +3176,8 @@ static int __init amd64_edac_init(void) if (cache_k8_northbridges() < 0) return err; + msrs = msrs_alloc(); + err = pci_register_driver(&amd64_pci_driver); if (err) return err; @@ -3228,6 +3213,9 @@ static void __exit amd64_edac_exit(void) edac_pci_release_generic_ctl(amd64_ctl_pci); pci_unregister_driver(&amd64_pci_driver); + + msrs_free(msrs); + msrs = NULL; } module_init(amd64_edac_init); -- 1.6.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/