From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chao Peng Subject: [PATCH] x86: avoid invalid phys_proc_id reference Date: Mon, 13 Jul 2015 11:36:26 +0800 Message-ID: <1436758586-20860-1-git-send-email-chao.p.peng@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xen.org Cc: andrew.cooper3@citrix.com, dario.faggioli@citrix.com, keir@xen.org, JBeulich@suse.com List-Id: xen-devel@lists.xenproject.org phys_proc_id is invalidated in remove_siblinginfo() which gets called before cpu_smpboot_free(). This means calling cpu_to_socket(cpu) in cpu_smpboot_free() is not possible to be correct. This patch invokes remove_siblinginfo() in cpu_smpboot_free(), immediately after the use for cpu_to_socket(cpu). The clearing of cpu_{core,sibling}_mask in remove_siblinginfo() is also removed as now both masks will get freed afterwards so clearing is useless. Signed-off-by: Chao Peng Reported-by: Dario Faggioli --- xen/arch/x86/smpboot.c | 55 +++++++++++++++++++++++++------------------------- 1 file changed, 27 insertions(+), 28 deletions(-) diff --git a/xen/arch/x86/smpboot.c b/xen/arch/x86/smpboot.c index 0f03364..ededa1c 100644 --- a/xen/arch/x86/smpboot.c +++ b/xen/arch/x86/smpboot.c @@ -320,6 +320,29 @@ static void set_cpu_sibling_map(int cpu) } } +static void +remove_siblinginfo(int cpu) +{ + int sibling; + struct cpuinfo_x86 *c = cpu_data; + + for_each_cpu ( sibling, per_cpu(cpu_core_mask, cpu) ) + { + cpumask_clear_cpu(cpu, per_cpu(cpu_core_mask, sibling)); + /* Last thread sibling in this cpu core going down. */ + if ( cpumask_weight(per_cpu(cpu_sibling_mask, cpu)) == 1 ) + c[sibling].booted_cores--; + } + + for_each_cpu(sibling, per_cpu(cpu_sibling_mask, cpu)) + cpumask_clear_cpu(cpu, per_cpu(cpu_sibling_mask, sibling)); + c[cpu].phys_proc_id = XEN_INVALID_SOCKET_ID; + c[cpu].cpu_core_id = XEN_INVALID_CORE_ID; + c[cpu].compute_unit_id = INVALID_CUID; + cpumask_clear_cpu(cpu, &cpu_sibling_setup_map); +} + + void start_secondary(void *unused) { /* @@ -667,12 +690,16 @@ static void cpu_smpboot_free(unsigned int cpu) { unsigned int order, socket = cpu_to_socket(cpu); + cpumask_clear_cpu(cpu, socket_cpumask[socket]); + if ( cpumask_empty(socket_cpumask[socket]) ) { xfree(socket_cpumask[socket]); socket_cpumask[socket] = NULL; } + remove_siblinginfo(cpu); + free_cpumask_var(per_cpu(cpu_sibling_mask, cpu)); free_cpumask_var(per_cpu(cpu_core_mask, cpu)); @@ -878,32 +905,6 @@ void __init smp_prepare_boot_cpu(void) cpumask_set_cpu(smp_processor_id(), &cpu_present_map); } -static void -remove_siblinginfo(int cpu) -{ - int sibling; - struct cpuinfo_x86 *c = cpu_data; - - cpumask_clear_cpu(cpu, socket_cpumask[cpu_to_socket(cpu)]); - - for_each_cpu ( sibling, per_cpu(cpu_core_mask, cpu) ) - { - cpumask_clear_cpu(cpu, per_cpu(cpu_core_mask, sibling)); - /* Last thread sibling in this cpu core going down. */ - if ( cpumask_weight(per_cpu(cpu_sibling_mask, cpu)) == 1 ) - c[sibling].booted_cores--; - } - - for_each_cpu(sibling, per_cpu(cpu_sibling_mask, cpu)) - cpumask_clear_cpu(cpu, per_cpu(cpu_sibling_mask, sibling)); - cpumask_clear(per_cpu(cpu_sibling_mask, cpu)); - cpumask_clear(per_cpu(cpu_core_mask, cpu)); - c[cpu].phys_proc_id = XEN_INVALID_SOCKET_ID; - c[cpu].cpu_core_id = XEN_INVALID_CORE_ID; - c[cpu].compute_unit_id = INVALID_CUID; - cpumask_clear_cpu(cpu, &cpu_sibling_setup_map); -} - void __cpu_disable(void) { int cpu = smp_processor_id(); @@ -919,8 +920,6 @@ void __cpu_disable(void) time_suspend(); - remove_siblinginfo(cpu); - /* It's now safe to remove this processor from the online map */ cpumask_clear_cpu(cpu, &cpu_online_map); fixup_irqs(); -- 1.9.1