On Sun, 28 Oct 2007, Matthew Wilcox wrote: > Bzzt. You get a false deadlock with multiple threads like so: > Thread A of task B takes lock 1 > Thread C of task D takes lock 2 > Thread C of task D blocks on lock 1 > Thread E of task B blocks on lock 2 A potential for deadlock occurs if a process controlling a locked region is put to sleep by attempting to lock another process' locked region. If the system detects that sleeping until a locked region is unlocked would cause a deadlock, fcntl() shall fail with an [EDEADLK] error. This is what POSIX says [1], even after being modified with respect to POSIX Threads Extension, right? So it doesn't deal with threads at all, just processess are taken into account. Probably for a reason :) [1] http://www.opengroup.org/onlinepubs/009695399/functions/fcntl.html -- Jiri Kosina - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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