Messages in this thread |  | | Subject | Re: net/dccp: warning in dccp_feat_clone_sp_val/__might_sleep | From | Eric Dumazet <> | Date | Sun, 30 Oct 2016 06:20:01 -0700 |
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On Sun, 2016-10-30 at 05:41 +0100, Andrey Konovalov wrote: > Sorry, the warning is still there. > > I'm not sure adding sched_annotate_sleep() does anything, since it's > defined as (in case CONFIG_DEBUG_ATOMIC_SLEEP is not set): > # define sched_annotate_sleep() do { } while (0)
Thanks again for testing.
But you do have CONFIG_DEBUG_ATOMIC_SLEEP set, which triggers a check in __might_sleep() :
WARN_ONCE(current->state != TASK_RUNNING && current->task_state_change,
Relevant commit is 00845eb968ead28007338b2bb852b8beef816583 ("sched: don't cause task state changes in nested sleep debugging")
Another relevant commit was 26cabd31259ba43f68026ce3f62b78094124333f ("sched, net: Clean up sk_wait_event() vs. might_sleep()")
Before release_sock() could process the backlog in process context, only lock_sock() could trigger the issue, so my fix at that time was commit cb7cf8a33ff73cf638481d1edf883d8968f934f8 ("inet: Clean up inet_csk_wait_for_connect() vs. might_sleep()")
I guess we need something else now, because the following :
static int dccp_wait_for_ccid(struct sock *sk, unsigned long delay) { DEFINE_WAIT(wait); long remaining;
prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE); sk->sk_write_pending++; release_sock(sk); ...
can now process the socket backlog in process context from release_sock(), so all GFP_KERNEL allocations might barf because of TASK_INTERRUPTIBLE being used at that point.
sk_wait_event() probably also needs a fix.
Peter, any idea how this can be done ?
Thanks !
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