This is the mail archive of the
gdb-patches@sourceware.org
mailing list for the GDB project.
Re: [PATCH v4 0/7] Remote fork events
- From: "Breazeal, Don" <donb at codesourcery dot com>
- To: "gdb-patches at sourceware dot org" <gdb-patches at sourceware dot org>, Pedro Alves <palves at redhat dot com>
- Date: Fri, 6 Feb 2015 12:02:30 -0800
- Subject: Re: [PATCH v4 0/7] Remote fork events
- Authentication-results: sourceware.org; auth=none
- References: <201501252151 dot t0PLo3jE018308 at mx0b-0013c101 dot pphosted dot com> <54C566F2 dot 2020302 at codesourcery dot com>
Ping.
Full remote follow fork patch series includes:
1/7: https://sourceware.org/ml/gdb-patches/2015-01/msg00686.html
2/7: https://sourceware.org/ml/gdb-patches/2015-01/msg00687.html
3/7: https://sourceware.org/ml/gdb-patches/2015-01/msg00689.html
4/7: https://sourceware.org/ml/gdb-patches/2015-01/msg00690.html
5/7: https://sourceware.org/ml/gdb-patches/2015-01/msg00685.html
6/7: https://sourceware.org/ml/gdb-patches/2015-01/msg00684.html
7/7: https://sourceware.org/ml/gdb-patches/2015-01/msg00688.html
Thanks,
--Don
On 1/25/2015 1:58 PM, Breazeal, Don wrote:
>
> From: Don Breazeal <donb@codesourcery.com>
> Subject: [PATCH v4 0/7] Remote fork events
> In-Reply-To: <54C236B9.8060200@redhat.com>
>
>
> This is an update to the patch series implementing remote follow-fork.
> This update only implements fork and vfork events, omitting exec events
> for now.
>
> The series has been renumbered, since the numbering of the original patch
> series has little relevance now. Let me know if I should maintain the
> original numbering.
>
> The primary difference between this series and previous versions is that
> it includes support for 'target remote' as well as extended-remote. It
> also eliminates the vFollowFork packet used in previous versions and uses
> the qSupported packet to determine if fork events are supported by
> gdbserver.
>
> The new series includes seven patches as follows:
>
> 1/7: Preparatory patch that implements qSupported support for fork events
> and associated mechanisms.
>
> 2/7: Implements functions to clone breakpoint lists in gdbserver.
>
> 3/7: Implements follow fork for 'fork' but not 'vfork' and for
> extended-remote
> targets only. Note subject line was garbled, see ERRATA below.
>
> 4/7: Extends follow fork for 'fork' to 'target remote' as well as
> extended-remote.
>
> 5/7: Adds the architecture-specific pieces of follow-fork that allows
> hardware watchpoints to be inherited by a forked child.
>
> 6/7: Adds follow fork for 'vfork'.
>
> 7/7: Adds catchpoints for 'fork' and 'vfork', along with support for
> killing a process that has forked but has not been followed.
>
>
> ERRATA:
> I have to apologize in advance for a few minor formatting and coding
> errors, listed below. I decided that these were trivial enough that
> they didn't warrant the delay required to go through the whole rebase/test
> cycle. The issues are:
>
> 4/7: in linux-low.c there is a blank line containing spaces.
> 4/7: in remote.c, I left a /* XXX */ comment.
> 4/7: in remote.c there is an unnecessary static declaration of
> extended_remote_kill
>
> The subject line of patch 3 was garbled somehow. Sent on 25-Jan-2015,
> it reads "Re: [PATCH v4 3/7 v3] Extended-remote Linux follow fork" when
> it should read "[PATCH v4 3/7] Extended-remote-Linux follow fork". My
> incompetent use of --in-reply-to with git send-email, I'm sure.
>
>
> TESTING:
> Testing was mostly done using x86_64 Ubuntu, with the exception of the
> architecture-specific patch, #5. There are a few anomalies that show
> up, but don't signify any problem.
>
> - Intermediate patches show failures due to the lack of features
> implemented in subsequent patches, like missing hardware watchpoint
> or catchpoint support.
>
> - Some vfork tests fail due to the lack of exec event support.
>
> - There are a couple of tests that show new failures that actually
> fail in the current mainline. Details of these are as follows:
>
> * when vfork events are enabled, gdb.base/disp-step-syscall.exp
> shows PASS => FAIL in .sum diffs. The test actually always
> fails. With native/master, we see
>
> stepi^M
> FAIL: gdb.base/disp-step-syscall.exp: vfork: stepi vfork insn
> (timeout)
>
> With remote and extended-remote/master, we see a bogus PASS result:
> stepi^M
> [Inferior 1 (process 9399) exited normally]^M
> (gdb) PASS: gdb.base/disp-step-syscall.exp: vfork: stepi vfork insn
>
> The criteria to pass that test are pretty lax:
> gdb_test "stepi" ".*" "stepi $syscall insn"
>
> * Similarly, once vfork events are enabled, gdb.base/watch-vfork.exp
> shows PASS => FAIL in .sum diffs. This test also always fails. With
> native/master, we see this:
>
> continue^M
> Continuing.^M
> FAIL: gdb.base/watch-vfork.exp: Watchpoint triggers after vfork
> (sw) (timeout)
>
> With extended-remote/master, we see this:
> continue
> Continuing.
> [Inferior 1 (process 18866) exited normally]
> (gdb) FAIL: gdb.base/watch-vfork.exp: Watchpoint triggers after
> vfork (sw) (the program exited)
>
> But once vfork events are enabled, we see:
> continue
> Continuing.
> Detaching from process 17405
> FAIL: gdb.base/watch-vfork.exp: Watchpoint triggers after vfork
> (sw) (timeout)
> which more-or-less matches the native/master behavior.
>
> Thanks,
> --Don
>
>
>