From: Max Reitz <mreitz@redhat.com>
To: Laszlo Ersek <lersek@redhat.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>
Subject: Re: Thread safety of coroutine-sigaltstack
Date: Fri, 22 Jan 2021 09:48:07 +0100 [thread overview]
Message-ID: <fc35da77-a5c2-08dd-05f2-0ebe781b338c@redhat.com> (raw)
In-Reply-To: <445268c9-d91f-af5a-3d7e-f4c6f014ca52@redhat.com>
On 20.01.21 18:25, Laszlo Ersek wrote:
[...]
> A simple grep for SIGUSR2 seems to indicate that SIGUSR2 is not used by
> system emulation for anything else, in practice. Is it possible to
> dedicate SIGUSR2 explicitly to coroutine-sigaltstack, and set up the
> action beforehand, from some init function that executes on a "central"
> thread, before qemu_coroutine_new() is ever called?
I wrote a patch to that effect, but just before sending I wondered
whether SIGUSR2 cannot be registered by the “guest” in user-mode
emulation, and whether that would then break coroutines from there on.
(I have no experience dealing with user-mode emulation, but it does look
like the guest can just register handlers for any signal but SIGSEGV and
SIGBUS.)
Max
next prev parent reply other threads:[~2021-01-22 8:49 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-20 16:26 Thread safety of coroutine-sigaltstack Max Reitz
2021-01-20 16:50 ` Paolo Bonzini
2021-01-20 16:58 ` Eric Blake
2021-01-20 17:25 ` Laszlo Ersek
2021-01-21 9:27 ` Max Reitz
2021-01-21 13:34 ` Laszlo Ersek
2021-01-21 15:42 ` Max Reitz
2021-01-21 16:04 ` Daniel P. Berrangé
2021-01-21 16:05 ` Laszlo Ersek
2021-01-21 15:14 ` Paolo Bonzini
2021-01-21 16:07 ` Daniel P. Berrangé
2021-01-21 16:44 ` Peter Maydell
2021-01-21 17:24 ` Paolo Bonzini
2021-01-22 20:38 ` Laszlo Ersek
2021-01-22 21:34 ` Laszlo Ersek
2021-01-22 21:41 ` Laszlo Ersek
2021-01-22 7:55 ` Markus Armbruster
2021-01-22 8:48 ` Max Reitz [this message]
2021-01-22 10:14 ` Peter Maydell
2021-01-22 10:16 ` Max Reitz
2021-01-22 12:24 ` Laszlo Ersek
2021-01-23 0:06 ` Laszlo Ersek
2021-01-23 13:35 ` Peter Maydell
2021-01-25 22:15 ` Laszlo Ersek
2021-01-25 22:45 ` Paolo Bonzini
2021-01-26 8:57 ` Laszlo Ersek
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=fc35da77-a5c2-08dd-05f2-0ebe781b338c@redhat.com \
--to=mreitz@redhat.com \
--cc=kwolf@redhat.com \
--cc=lersek@redhat.com \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.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).