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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check-all.sh | -rw-r--r-- | 434 bytes |
rt-tester.py | -rw-r--r-- | 5.2 KB |
t2-l1-2rt-sameprio.tst | -rw-r--r-- | 1.5 KB |
t2-l1-pi.tst | -rw-r--r-- | 1.2 KB |
t2-l1-signal.tst | -rw-r--r-- | 1.2 KB |
t2-l2-2rt-deadlock.tst | -rw-r--r-- | 1.3 KB |
t3-l1-pi-1rt.tst | -rw-r--r-- | 1.4 KB |
t3-l1-pi-2rt.tst | -rw-r--r-- | 1.4 KB |
t3-l1-pi-3rt.tst | -rw-r--r-- | 1.4 KB |
t3-l1-pi-signal.tst | -rw-r--r-- | 1.5 KB |
t3-l1-pi-steal.tst | -rw-r--r-- | 1.6 KB |
t3-l2-pi.tst | -rw-r--r-- | 1.4 KB |
t4-l2-pi-deboost.tst | -rw-r--r-- | 2.0 KB |
t5-l4-pi-boost-deboost-setsched.tst | -rw-r--r-- | 2.9 KB |
t5-l4-pi-boost-deboost.tst | -rw-r--r-- | 2.2 KB |
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