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Date: Thu, 16 Dec 2021 16:09:19 -0500 (EST)
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To: Florian Weimer <fweimer@redhat.com>
Cc: libc-alpha <libc-alpha@sourceware.org>, 
 Simon Marchi <simon.marchi@efficios.com>, gdb@sourceware.org
Message-ID: <1507387605.36435.1639688959308.JavaMail.zimbra@efficios.com>
Subject: rseq and gdb
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Thread-Topic: rseq and gdb
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Hi Florian,

I suspect that gdb should ideally do something to allow it to single-step
through rseq critical sections. In librseq [1], we emit the __rseq_cs_ptr_array
and __rseq_exit_point_array sections to allow gdb to know about rseq
critical sections and skip over those critical sections as needed. Otherwise
single-stepping over each instruction of a rseq critical section will loop
forever.

Now that glibc plans to enable rseq by default starting with glibc 2.35,
it appears to be a good timing to raise this topic with the gdb community.

Thanks,

Mathieu

[1] https://git.kernel.org/pub/scm/libs/librseq/librseq.git

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com