Messages in this thread | | | From | Linus Torvalds <> | Date | Wed, 13 Jun 2018 09:25:03 -0700 | Subject | Re: [PATCH] bdi: Fix another oops in wb_workfn() |
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On Wed, Jun 13, 2018 at 9:21 AM Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> wrote: > > Since multiple addresses share bit_wait_table[256], isn't it possible that > cgwb_start_shutdown() prematurely returns false due to wake_up_bit() by > hash-conflicting addresses (i.e. not limited to clear_and_wake_up_bit() from > wb_shutdown())? I think that we cannot be sure without confirming that > test_bit(WB_shutting_down, &wb->state) == false after returning from schedule().
Right.
That's _always_ true, btw. Something else entirely could have woken you up. TASK_UNINTERRUPTIBLE does not mean "nothing else wakes me", it just means "_signals_ don't wake me".
So every single sleep always needs to be in a loop. Always.
Linus
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