Messages in this thread | | | Subject | Re: [PATCH v3] Make PTRACE_SEIZE set ptrace options specified in 'data' | From | Denys Vlasenko <> | Date | Fri, 09 Sep 2011 14:28:55 +0200 |
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On Fri, 2011-09-09 at 12:12 +0100, Pedro Alves wrote: > On Thursday 08 September 2011 19:22:04, Denys Vlasenko wrote: > > Make PTRACE_SEIZE set ptrace options specified in 'data' parameter > > > > This can be used to close a few corner cases in strace where we get > > unwanted racy behavior after attach, but before we have a chance > > to set options (the notorious post-execve SIGTRAP comes to mind), > > I'm still confused on why you're raising the SIGTRAP argument. Did you see > > https://lkml.org/lkml/2011/9/8/7 > > From previous discussions, I understood that PTRACE_SEIZE _always_ > disables > the post-execve SIGTRAP, so I don't believe that race actually exists. > Or is that not the case?
I believe it is not the case. And I object to making it the case. My sense of taste says the approach "you need to use SEIZE to affect feature <foo>" for various unrelated <foo> makes ptrace API ugly. Especially that in this case, we already have a method in API to suppress post-execve SIGTRAP.
-- vda
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