Messages in this thread |  | | | From | Roland McGrath <> | | Subject | Re: [BUG] signal: multithread program returns with wrong errno on receiving SIGSTOP | | Date | Tue, 29 May 2007 00:33:54 -0700 (PDT) |
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Your fix seems like the only way to go. From skimming all the ERESTART* uses, I think that in all cases (except for n_tty.c:job_control before your patch), TIF_SIGPENDING is indeed set when a thread returns -ERESTART*.
But it makes me realize that there is a danger of leaking a -ERESTART* return code to userland when TIF_SIGPENDING gets cleared by another thread doing a recalc_sigpending_tsk. Because of -ERESTART* I think we must make it a rule that no thread can clear another thread's TIF_SIGPENDING, only set it (unless it's known to be stopped in the signal code or something). From our recent work on it, I think that do_sigaction is in fact the only place this can happen. So that says we should err in the other direction from what I said before in do_sigaction, and not have it do recalc at all.
Thanks, Roland - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org 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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