mailing list of musl libc
 help / color / mirror / code / Atom feed
From: Rich Felker <dalias@libc.org>
To: enh <enh@google.com>
Cc: Khem Raj <raj.khem@gmail.com>, musl@lists.openwall.com
Subject: Re: [musl] SA_RESTORER for rv64?
Date: Mon, 6 Feb 2023 12:49:53 -0500	[thread overview]
Message-ID: <20230206174953.GP4163@brightrain.aerifal.cx> (raw)
In-Reply-To: <CAJgzZoqNmdV-vtYPOq2HYiQf_Vh5=NO5kF5+2mAWTaFF_HX41A@mail.gmail.com>

On Mon, Feb 06, 2023 at 08:51:13AM -0800, enh wrote:
> On Sun, Feb 5, 2023 at 3:54 PM Rich Felker <dalias@libc.org> wrote:
> >
> > On Fri, Feb 03, 2023 at 10:44:56AM -0800, enh wrote:
> > > oops, never actually sent the patch. attached...
> > >
> > > On Thu, Nov 10, 2022 at 9:31 AM Khem Raj <raj.khem@gmail.com> wrote:
> > > >
> > > > On Thu, Nov 10, 2022 at 9:19 AM Rich Felker <dalias@libc.org> wrote:
> > > > >
> > > > > On Thu, Nov 10, 2022 at 07:44:23AM -0800, enh wrote:
> > > > > > arch/riscv64/bits/signal.h has contained a definition for SA_RESTORER since
> > > > > > the initial commit, but i think that's just copy & paste from whichever
> > > > > > architecture the rv64 headers were based on? the linux kernel itself
> > > > > > doesn't have SA_RESTORER for rv64, unless i'm missing something?
> > > > >
> > > > > I suspect this is just a mistake. Have you seen any ill effects from
> > > > > it? If riscv folks can confirm it's wrong, I'll remove it.
> > > >
> > > > Yeah I think it should be removed. Perhaps mips is in same boat.
> > > >
> > > > >
> > > > > Rich
> >
> > > From 6413de6d9f785c98e5bc0cf40be947f1169d2fd7 Mon Sep 17 00:00:00 2001
> > > From: Elliott Hughes <enh@google.com>
> > > Date: Fri, 3 Feb 2023 10:42:55 -0800
> > > Subject: [PATCH] risc-v does not have SA_RESTORER.
> > >
> > > The kernel's include/uapi/asm-generic/signal-defs.h explicitly calls
> > > this out as obsolete. New architectures like risc-v do not define it.
> > > ---
> > >  arch/riscv64/bits/signal.h | 1 -
> > >  1 file changed, 1 deletion(-)
> > >
> > > diff --git a/arch/riscv64/bits/signal.h b/arch/riscv64/bits/signal.h
> > > index 287367db..fd6157a3 100644
> > > --- a/arch/riscv64/bits/signal.h
> > > +++ b/arch/riscv64/bits/signal.h
> > > @@ -76,7 +76,6 @@ typedef struct __ucontext
> > >  #define SA_RESTART   0x10000000
> > >  #define SA_NODEFER   0x40000000
> > >  #define SA_RESETHAND 0x80000000
> > > -#define SA_RESTORER  0x04000000
> > >
> > >  #endif
> > >
> > > --
> > > 2.39.1.519.gcb327c4b5f-goog
> > >
> >
> > I don't think this patch works as-is, since musl unconditionally uses
> > SA_RESTORER. We probably need to make that conditional on its
> > presence, and it looks like there's also a wrong-struct-layout issue
> > on archs where it's absent...
> 
> yeah, bionic just uses the kernel uapi headers directly, and they look
> like this:
> 
> struct sigaction {
>   __sighandler_t sa_handler;
>   unsigned long sa_flags;
> #ifdef SA_RESTORER
>   __sigrestore_t sa_restorer;
> #endif
>   sigset_t sa_mask;
> };

OK. It looks like we need to remove the wrong SA_RESTORER for archs
that aren't supposed to have it *and* add such an #ifdef. Right now,
we're passing bogus sa_mask on these archs... :(

Rich

  reply	other threads:[~2023-02-06 17:50 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-11-10 15:44 enh
2022-11-10 17:18 ` Rich Felker
2022-11-10 17:26   ` enh
2022-11-10 17:31   ` Khem Raj
2023-02-03 18:44     ` enh
2023-02-05 23:54       ` Rich Felker
2023-02-06 16:51         ` enh
2023-02-06 17:49           ` Rich Felker [this message]
2023-02-08 21:45             ` Rich Felker
2023-02-08 21:53               ` enh

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=20230206174953.GP4163@brightrain.aerifal.cx \
    --to=dalias@libc.org \
    --cc=enh@google.com \
    --cc=musl@lists.openwall.com \
    --cc=raj.khem@gmail.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.
Code repositories for project(s) associated with this public inbox

	https://git.vuxu.org/mirror/musl/

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).