Revision 73863ab028579ed98c4f1f36d016536b1b415344 authored by Anton Vorontsov on 31 May 2012, 23:26:23 UTC, committed by Linus Torvalds on 01 June 2012, 00:49:29 UTC
Current CPU hotplug code has some task->mm handling issues: 1. Working with task->mm w/o getting mm or grabing the task lock is dangerous as ->mm might disappear (exit_mm() assigns NULL under task_lock(), so tasklist lock is not enough). We can't use get_task_mm()/mmput() pair as mmput() might sleep, so we must take the task lock while handle its mm. 2. Checking for process->mm is not enough because process' main thread may exit or detach its mm via use_mm(), but other threads may still have a valid mm. To fix this we would need to use find_lock_task_mm(), which would walk up all threads and returns an appropriate task (with task lock held). clear_tasks_mm_cpumask() has all the issues fixed, so let's use it. Suggested-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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File | Mode | Size |
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Kconfig | -rw-r--r-- | 5.8 KB |
Makefile | -rw-r--r-- | 615 bytes |
amd_iommu.c | -rw-r--r-- | 82.4 KB |
amd_iommu_init.c | -rw-r--r-- | 42.9 KB |
amd_iommu_proto.h | -rw-r--r-- | 2.7 KB |
amd_iommu_types.h | -rw-r--r-- | 19.6 KB |
amd_iommu_v2.c | -rw-r--r-- | 22.6 KB |
dmar.c | -rw-r--r-- | 31.3 KB |
exynos-iommu.c | -rw-r--r-- | 25.1 KB |
intel-iommu.c | -rw-r--r-- | 105.2 KB |
intel_irq_remapping.c | -rw-r--r-- | 24.1 KB |
iommu.c | -rw-r--r-- | 8.6 KB |
iova.c | -rw-r--r-- | 11.5 KB |
irq_remapping.c | -rw-r--r-- | 3.2 KB |
irq_remapping.h | -rw-r--r-- | 2.5 KB |
msm_iommu.c | -rw-r--r-- | 16.9 KB |
msm_iommu_dev.c | -rw-r--r-- | 8.9 KB |
omap-iommu-debug.c | -rw-r--r-- | 9.6 KB |
omap-iommu.c | -rw-r--r-- | 26.6 KB |
omap-iovmm.c | -rw-r--r-- | 16.0 KB |
tegra-gart.c | -rw-r--r-- | 11.0 KB |
tegra-smmu.c | -rw-r--r-- | 26.9 KB |
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