From: Ryan Sullivan <rysulliv@redhat.com>
To: live-patching@vger.kernel.org, linuxppc-dev@lists.ozlabs.org
Cc: pmladek@suse.com, joe.lawrence@redhat.com, jikos@kernel.org,
christophe.leroy@csgroup.eu, rysulliv@redhat.com,
npiggin@gmail.com, naveen.n.rao@linux.ibm.com, mbenes@suse.cz,
jpoimboe@kernel.org
Subject: Re: [PATCH] powerpc/ftrace: restore r2 to caller's stack on livepatch sibling call
Date: Mon, 29 Jul 2024 11:02:36 -0400 [thread overview]
Message-ID: <20240729150246.8939-1-rysulliv@redhat.com> (raw)
In-Reply-To: <878qxkp9jl.fsf@mail.lhotse>
Hello Michael,
In the case of no sibling call within the livepatch then the store is
only "restoring" the r2 value that was already there as it is stored
and retrieved from the livepatch stack. The only time that the r2 value
is corrupted is in the case of a sibling call and thus this additional
store is just restoring the caller's context as a safety precaution.
Also should this explanation be put into the patch itself or will these
messages suffice as a reference?
Cheers,
Ryan
next prev parent reply other threads:[~2024-07-29 22:48 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-07-24 18:33 [PATCH] powerpc/ftrace: restore r2 to caller's stack on livepatch sibling call Ryan Sullivan
2024-07-29 14:17 ` Michael Ellerman
2024-07-29 15:02 ` Ryan Sullivan [this message]
2024-08-15 10:22 ` Michael Ellerman
2024-08-15 16:07 ` Ryan Sullivan
2024-08-15 16:24 ` Joe Lawrence
2024-09-09 16:33 ` Ryan B. Sullivan
2024-09-10 7:21 ` Michael Ellerman
2024-09-10 15:02 ` Ryan B. Sullivan
2024-08-08 7:00 ` Christophe Leroy
2024-08-08 17:55 ` [PATCH v2] powerpc/ftrace: restore caller's toc on ppc64 " Ryan Sullivan
2024-08-08 21:17 ` Ryan Sullivan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20240729150246.8939-1-rysulliv@redhat.com \
--to=rysulliv@redhat.com \
--cc=christophe.leroy@csgroup.eu \
--cc=jikos@kernel.org \
--cc=joe.lawrence@redhat.com \
--cc=jpoimboe@kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=live-patching@vger.kernel.org \
--cc=mbenes@suse.cz \
--cc=naveen.n.rao@linux.ibm.com \
--cc=npiggin@gmail.com \
--cc=pmladek@suse.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).