From: Simon Marchi <simark@simark.ca>
To: Pedro Alves <pedro@palves.net>,
Simon Marchi <simon.marchi@efficios.com>,
gdb-patches@sourceware.org
Subject: Re: [PATCH 02/12] gdb: clear inferior displaced stepping state on exec
Date: Mon, 30 Nov 2020 23:27:12 -0500 [thread overview]
Message-ID: <b1642128-afe4-72aa-e21e-0b130e1bb47a@simark.ca> (raw)
In-Reply-To: <43495e04-beb9-bf75-0bc1-efcce540fa57@palves.net>
On 2020-11-24 8:28 p.m., Pedro Alves wrote:
>> I tried to write a test where a non-main thread displaced-steps an exec
>> syscall, where things would hang due to the displaced step buffer not
>> getting released. However, due to PR 26754 [1], it is hard to make it
>> stable. So I'm not including a test for this patch. If you have an
>> idea for another way to test this without triggering this bug, I'd like
>> to hear it.
>>
>> [1] https://sourceware.org/bugzilla/show_bug.cgi?id=26754
> I can't think of another way to test this.
>
We can simply put a breakpoint with an always false condition on the
syscall instruction and run from start. The exec will be displaced
stepped while the main thread will run. I can reliably reproduce the
hang this way.
Simon
next prev parent reply other threads:[~2020-12-01 4:27 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-10 21:46 [PATCH 00/12] Concurrent displaced stepping Simon Marchi via Gdb-patches
2020-11-10 21:46 ` [PATCH 01/12] gdb: add inferior_execd observable Simon Marchi via Gdb-patches
2020-11-25 1:28 ` Pedro Alves
2020-11-10 21:46 ` [PATCH 02/12] gdb: clear inferior displaced stepping state on exec Simon Marchi via Gdb-patches
2020-11-25 1:28 ` Pedro Alves
2020-12-01 4:27 ` Simon Marchi [this message]
2020-11-10 21:46 ` [PATCH 03/12] gdb: rename things related to step over chains Simon Marchi via Gdb-patches
2020-11-25 1:28 ` Pedro Alves
2020-11-25 13:16 ` Simon Marchi via Gdb-patches
2020-11-10 21:46 ` [PATCH 04/12] gdb: rename displaced_step_closure to displaced_step_copy_insn_closure Simon Marchi via Gdb-patches
2020-11-25 1:29 ` Pedro Alves
2020-11-10 21:46 ` [PATCH 05/12] gdb: rename displaced_step_fixup to displaced_step_finish Simon Marchi via Gdb-patches
2020-11-25 1:29 ` Pedro Alves
2020-11-10 21:46 ` [PATCH 06/12] gdb: introduce status enum for displaced step prepare/finish Simon Marchi via Gdb-patches
2020-11-11 23:36 ` Andrew Burgess
2020-11-25 13:17 ` Simon Marchi via Gdb-patches
2020-11-25 1:30 ` Pedro Alves
2020-11-25 13:20 ` Simon Marchi via Gdb-patches
2020-11-10 21:46 ` [PATCH 07/12] gdb: pass inferior to get_linux_inferior_data Simon Marchi via Gdb-patches
2020-11-25 1:30 ` Pedro Alves
2020-11-10 21:46 ` [PATCH 08/12] gdb: move displaced stepping types to displaced-stepping.{h, c} Simon Marchi via Gdb-patches
2020-11-25 1:30 ` Pedro Alves
2020-11-10 21:46 ` [PATCH 09/12] gdb: move displaced stepping logic to gdbarch, allow starting concurrent displaced steps Simon Marchi via Gdb-patches
2020-11-25 1:40 ` Pedro Alves
2020-11-25 19:29 ` Simon Marchi via Gdb-patches
2020-11-25 19:35 ` Simon Marchi
2020-11-26 14:25 ` Pedro Alves
2020-11-30 19:13 ` Simon Marchi via Gdb-patches
2020-11-26 14:24 ` Pedro Alves
2020-11-30 20:26 ` Simon Marchi
2020-11-10 21:46 ` [PATCH 10/12] gdb: change linux gdbarch data from post to pre-init Simon Marchi via Gdb-patches
2020-11-25 1:41 ` Pedro Alves
2020-11-10 21:46 ` [PATCH 11/12] gdb: make displaced stepping implementation capable of managing multiple buffers Simon Marchi via Gdb-patches
2020-11-25 1:41 ` Pedro Alves
2020-11-30 18:58 ` Simon Marchi
2020-11-30 19:01 ` Simon Marchi
2020-11-10 21:46 ` [PATCH 12/12] gdb: use two displaced step buffers on amd64/Linux Simon Marchi via Gdb-patches
2020-11-25 1:42 ` Pedro Alves
2020-11-25 6:26 ` Simon Marchi
2020-11-25 20:07 ` Simon Marchi
2020-11-25 20:56 ` Simon Marchi
2020-11-26 21:43 ` Simon Marchi
2020-11-26 22:34 ` Simon Marchi
2020-11-28 18:56 ` Pedro Alves
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