Messages in this thread | | | Date | Tue, 1 Aug 2006 01:22:17 -0400 | From | "Albert Cahalan" <> | Subject | Re: ptrace bugs and related problems |
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On 7/31/06, Daniel Jacobowitz <dan@debian.org> wrote: > On Mon, Jul 31, 2006 at 08:08:35PM -0400, Albert Cahalan wrote: > > The execve event is unreliable anyway. > > Thus, it is necessary to use syscall tracing. > > You keep saying this "unreliable" thing, and I don't think it means > what you think it means. It should always be delivered. When it > isn't, there's a bug. I don't know of any, unless you're talking about > the thread group issue you just reported.
Yeah, I figure there is a bug.
It'd be great if you could reproduce the bug. My setup:
2-core CPU 64-bit kernel (2.6.17 FC5, next-to-latest revision) 32-bit target app (assembly - no C library) 32-bit debugger
The target app does CLONE_THREAD. The child does that again, then execve. The first and last threads spin in a loop, either burning CPU time or doing the pause system call. (the middle thread does the execve)
I see the messages just fine on many 32-bit non-SMP systems that I tested with: Gentoo 2.6.16, Gentoo 2.6.13, plain 2.6.16, maybe 2.6.17.7... mostly in VMWare. Perhaps it is the SMP, the 64-bit, or Fedora being broken. I can not say, and most likely can not investigate more.
I hope that helps. - 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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