Commit-ID: fa74c9073370e57fa28e02aff13f4d7b1806505c Gitweb: http://git.kernel.org/tip/fa74c9073370e57fa28e02aff13f4d7b1806505c Author: Yinghai Lu <yinghai@xxxxxxxxxx> AuthorDate: Tue, 24 Mar 2009 13:23:16 -0700 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Tue, 24 Mar 2009 22:12:10 +0100 x86: fix set_extra_move_desc calling Impact: fix bug with irq-descriptor moving when logical flat Rusty observed: > The effect of setting desc->affinity (ie. from userspace via sysfs) has varied > over time. In 2.6.27, the 32-bit code anded the value with cpu_online_map, > and both 32 and 64-bit did that anding whenever a cpu was unplugged. > > 2.6.29 consolidated this into one routine (and fixed hotplug) but introduced > another variation: anding the affinity with cfg->domain. Is this right, or > should we just set it to what the user said? Or as now, indicate that we're > restricting it. Eric pointed out that desc->affinity should be what the user requested, if it is at all possible to honor the user space request. This bug got introduced by commit 22f65d31b "x86: Update io_apic.c to use new cpumask API". Fix it by moving the masking to before the descriptor moving ... Reported-by: Rusty Russell <rusty@xxxxxxxxxxxxxxx> Reported-by: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> LKML-Reference: <49C94134.4000408@xxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- arch/x86/kernel/apic/io_apic.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c index 86827d8..1ed6c06 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -592,8 +592,9 @@ set_desc_affinity(struct irq_desc *desc, const struct cpumask *mask) if (assign_irq_vector(irq, cfg, mask)) return BAD_APICID; - cpumask_and(desc->affinity, cfg->domain, mask); + /* check that before desc->addinity get updated */ set_extra_move_desc(desc, mask); + cpumask_and(desc->affinity, cfg->domain, mask); return apic->cpu_mask_to_apicid_and(desc->affinity, cpu_online_mask); } -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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