73863ab028
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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| .. | ||
| 40x_mmu.c | ||
| 44x_mmu.c | ||
| Makefile | ||
| dma-noncoherent.c | ||
| fault.c | ||
| fsl_booke_mmu.c | ||
| gup.c | ||
| hash_low_32.S | ||
| hash_low_64.S | ||
| hash_native_64.c | ||
| hash_utils_64.c | ||
| highmem.c | ||
| hugetlbpage-book3e.c | ||
| hugetlbpage-hash64.c | ||
| hugetlbpage.c | ||
| icswx.c | ||
| icswx.h | ||
| icswx_pid.c | ||
| init_32.c | ||
| init_64.c | ||
| mem.c | ||
| mmap_64.c | ||
| mmu_context_hash32.c | ||
| mmu_context_hash64.c | ||
| mmu_context_nohash.c | ||
| mmu_decl.h | ||
| numa.c | ||
| pgtable.c | ||
| pgtable_32.c | ||
| pgtable_64.c | ||
| ppc_mmu_32.c | ||
| slb.c | ||
| slb_low.S | ||
| slice.c | ||
| stab.c | ||
| subpage-prot.c | ||
| tlb_hash32.c | ||
| tlb_hash64.c | ||
| tlb_low_64e.S | ||
| tlb_nohash.c | ||
| tlb_nohash_low.S | ||