From a775a38b1353161a6d7af86b667d6523c12c1a37 Mon Sep 17 00:00:00 2001 From: Mike Travis Date: Wed, 17 Dec 2008 15:21:39 -0800 Subject: x86: fix cpu_mask_to_apicid_and to include cpu_online_mask Impact: fix potential APIC crash In determining the destination apicid, there are usually three cpumasks that are considered: the incoming cpumask arg, cfg->domain and the cpu_online_mask. Since we are just introducing the cpu_mask_to_apicid_and function, make sure it includes the cpu_online_mask in it's evaluation. [Added with this patch.] There are two io_apic.c functions that did not previously use the cpu_online_mask: setup_IO_APIC_irq and msi_compose_msg. Both of these simply used cpu_mask_to_apicid(cfg->domain & TARGET_CPUS), and all but one arch (NUMAQ[*]) returns only online cpus in the TARGET_CPUS mask, so the behavior is identical for all cases. [*: NUMAQ bug?] Note that alloc_cpumask_var is only used for the 32-bit cases where it's highly likely that the cpumask set size will be small and therefore CPUMASK_OFFSTACK=n. But if that's not the case, failing the allocate will cause the same return value as the default. Signed-off-by: Mike Travis Signed-off-by: Ingo Molnar --- arch/x86/include/asm/summit/apic.h | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) (limited to 'arch/x86/include/asm/summit') diff --git a/arch/x86/include/asm/summit/apic.h b/arch/x86/include/asm/summit/apic.h index 651a9384934..99327d1be49 100644 --- a/arch/x86/include/asm/summit/apic.h +++ b/arch/x86/include/asm/summit/apic.h @@ -170,35 +170,37 @@ static inline unsigned int cpu_mask_to_apicid(const cpumask_t *cpumask) return apicid; } -static inline unsigned int cpu_mask_to_apicid_and(const struct cpumask *cpumask, +static inline unsigned int cpu_mask_to_apicid_and(const struct cpumask *inmask, const struct cpumask *andmask) { int num_bits_set; - int num_bits_set2; int cpus_found = 0; int cpu; - int apicid = 0; + int apicid = 0xFF; + cpumask_var_t cpumask; + + if (!alloc_cpumask_var(&cpumask, GFP_ATOMIC)) + return (int) 0xFF; + + cpumask_and(cpumask, inmask, andmask); + cpumask_and(cpumask, cpumask, cpu_online_mask); num_bits_set = cpumask_weight(cpumask); - num_bits_set2 = cpumask_weight(andmask); - num_bits_set = min(num_bits_set, num_bits_set2); /* Return id to all */ - if (num_bits_set >= nr_cpu_ids) - return 0xFF; + if (num_bits_set == nr_cpu_ids) + goto exit; /* * The cpus in the mask must all be on the apic cluster. If are not * on the same apicid cluster return default value of TARGET_CPUS. */ - cpu = cpumask_first_and(cpumask, andmask); + cpu = cpumask_first(cpumask); apicid = cpu_to_logical_apicid(cpu); while (cpus_found < num_bits_set) { - if (cpumask_test_cpu(cpu, cpumask) - && cpumask_test_cpu(cpu, andmask)) { + if (cpumask_test_cpu(cpu, cpumask)) { int new_apicid = cpu_to_logical_apicid(cpu); if (apicid_cluster(apicid) != - apicid_cluster(new_apicid)) { - printk(KERN_WARNING - "%s: Not a valid mask!\n", __func__); + apicid_cluster(new_apicid)){ + printk ("%s: Not a valid mask!\n", __func__); return 0xFF; } apicid = apicid | new_apicid; @@ -206,6 +208,8 @@ static inline unsigned int cpu_mask_to_apicid_and(const struct cpumask *cpumask, } cpu++; } +exit: + free_cpumask_var(cpumask); return apicid; } -- cgit v1.2.3