All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Dmitry V. Levin" <ldv@altlinux.org>
To: Nicholas Piggin <npiggin@gmail.com>,
	Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev@lists.ozlabs.org, musl@lists.openwall.com,
	libc-dev@lists.llvm.org, linux-api@vger.kernel.org
Subject: Re: Linux powerpc new system call instruction and ABI
Date: Wed, 19 May 2021 02:13:31 +0300	[thread overview]
Message-ID: <20210518231331.GA8464@altlinux.org> (raw)
In-Reply-To: <20200611081203.995112-1-npiggin@gmail.com>

Hi,

On Thu, Jun 11, 2020 at 06:12:01PM +1000, Nicholas Piggin wrote:
[...]
> - Error handling: The consensus among kernel, glibc, and musl is to move to
>   using negative return values in r3 rather than CR0[SO]=1 to indicate error,
>   which matches most other architectures, and is closer to a function call.

Apparently, the patchset merged by commit v5.9-rc1~100^2~164 was
incomplete: all functions defined in arch/powerpc/include/asm/ptrace.h and
arch/powerpc/include/asm/syscall.h that use ccr are broken when scv is used.
This includes syscall_get_error() and all its users including
PTRACE_GET_SYSCALL_INFO API, which in turn makes strace unusable
when scv is used.

See also https://bugzilla.redhat.com/1929836


-- 
ldv

WARNING: multiple messages have this Message-ID (diff)
From: "Dmitry V. Levin" <ldv@altlinux.org>
To: Nicholas Piggin <npiggin@gmail.com>,
	Michael Ellerman <mpe@ellerman.id.au>
Cc: musl@lists.openwall.com, linux-api@vger.kernel.org,
	linuxppc-dev@lists.ozlabs.org, libc-dev@lists.llvm.org
Subject: Re: Linux powerpc new system call instruction and ABI
Date: Wed, 19 May 2021 02:13:31 +0300	[thread overview]
Message-ID: <20210518231331.GA8464@altlinux.org> (raw)
In-Reply-To: <20200611081203.995112-1-npiggin@gmail.com>

Hi,

On Thu, Jun 11, 2020 at 06:12:01PM +1000, Nicholas Piggin wrote:
[...]
> - Error handling: The consensus among kernel, glibc, and musl is to move to
>   using negative return values in r3 rather than CR0[SO]=1 to indicate error,
>   which matches most other architectures, and is closer to a function call.

Apparently, the patchset merged by commit v5.9-rc1~100^2~164 was
incomplete: all functions defined in arch/powerpc/include/asm/ptrace.h and
arch/powerpc/include/asm/syscall.h that use ccr are broken when scv is used.
This includes syscall_get_error() and all its users including
PTRACE_GET_SYSCALL_INFO API, which in turn makes strace unusable
when scv is used.

See also https://bugzilla.redhat.com/1929836


-- 
ldv

  parent reply	other threads:[~2021-05-18 23:13 UTC|newest]

Thread overview: 83+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-11  8:12 Linux powerpc new system call instruction and ABI Nicholas Piggin
2020-06-11  8:12 ` Nicholas Piggin
2020-06-11  8:12 ` [PATCH 1/2] powerpc/64s/exception: treat NIA below __end_interrupts as soft-masked Nicholas Piggin
2020-06-11  8:12   ` Nicholas Piggin
2020-07-24 13:25   ` Michael Ellerman
2020-07-24 13:25     ` Michael Ellerman
2020-06-11  8:12 ` [PATCH 2/2] powerpc/64s: system call support for scv/rfscv instructions Nicholas Piggin
2020-06-11  8:12   ` Nicholas Piggin
2020-07-23  6:47   ` Michael Ellerman
2020-07-23 16:48     ` Christophe Leroy
2020-07-23 16:48       ` Christophe Leroy
2020-07-24 10:45       ` Michael Ellerman
2020-07-24 10:45         ` Michael Ellerman
2020-06-11 21:02 ` Linux powerpc new system call instruction and ABI Segher Boessenkool
2020-06-11 21:02   ` Segher Boessenkool
2020-06-14  9:26   ` Nicholas Piggin
2020-06-14  9:26     ` Nicholas Piggin
2021-05-18 23:13 ` Dmitry V. Levin [this message]
2021-05-18 23:13   ` Dmitry V. Levin
2021-05-19  2:50   ` Nicholas Piggin
2021-05-19  2:50     ` Nicholas Piggin
2021-05-19  5:01     ` Nicholas Piggin
2021-05-19  5:01       ` Nicholas Piggin
2021-05-21 19:40       ` Matheus Castanho
2021-05-21 19:40         ` Matheus Castanho
2021-05-21 19:52         ` Florian Weimer
2021-05-21 19:52           ` Florian Weimer
2021-05-21 20:00           ` Matheus Castanho
2021-05-21 20:00             ` Matheus Castanho
2021-05-21 20:52             ` Dmitry V. Levin
2021-05-21 20:52               ` Dmitry V. Levin
2021-05-24 12:11               ` Matheus Castanho
2021-05-24 12:11                 ` Matheus Castanho
2021-05-24 20:33                 ` Matheus Castanho
2021-05-24 20:33                   ` Matheus Castanho
2021-05-19 10:24     ` Dmitry V. Levin
2021-05-19 10:24       ` Dmitry V. Levin
2021-05-19 10:59       ` Nicholas Piggin
2021-05-19 10:59         ` Nicholas Piggin
2021-05-19 12:39         ` Tulio Magno Quites Machado Filho
2021-05-19 12:39           ` Tulio Magno Quites Machado Filho
2021-05-19 13:26         ` Dmitry V. Levin
2021-05-19 13:26           ` Dmitry V. Levin
2021-05-19 22:51           ` Nicholas Piggin
2021-05-19 22:51             ` Nicholas Piggin
2021-05-19 23:27             ` Dmitry V. Levin
2021-05-19 23:27               ` Dmitry V. Levin
2021-05-20  2:40               ` Nicholas Piggin
2021-05-20  2:40                 ` Nicholas Piggin
2021-05-20  3:06                 ` Dmitry V. Levin
2021-05-20  3:06                   ` Dmitry V. Levin
2021-05-20  5:12                   ` Nicholas Piggin
2021-05-20  5:12                     ` Nicholas Piggin
2021-05-19  7:33   ` Joakim Tjernlund
2021-05-19  7:33     ` Joakim Tjernlund
2021-05-19  7:55     ` Nicholas Piggin
2021-05-19  7:55       ` Nicholas Piggin
2021-05-19  8:08       ` Joakim Tjernlund
2021-05-19  8:08         ` Joakim Tjernlund
2021-05-19  8:42         ` Nicholas Piggin
2021-05-19  8:42           ` Nicholas Piggin
2021-05-19 11:12           ` Nicholas Piggin
2021-05-19 11:12             ` Nicholas Piggin
2021-05-19 14:38           ` Segher Boessenkool
2021-05-19 14:38             ` Segher Boessenkool
2021-05-19 15:06             ` Joakim Tjernlund
2021-05-19 15:06               ` Joakim Tjernlund
2021-05-19 15:22               ` Segher Boessenkool
2021-05-19 15:22                 ` Segher Boessenkool
2021-05-19 15:36                 ` [musl] " Rich Felker
2021-05-19 15:36                   ` Rich Felker
2021-05-19 18:09                 ` Joakim Tjernlund
2021-05-19 18:09                   ` Joakim Tjernlund
2021-05-19 23:48                   ` [musl] " Rich Felker
2021-05-19 23:48                     ` Rich Felker
2021-05-20  1:06                     ` Dmitry V. Levin
2021-05-20  1:06                       ` Dmitry V. Levin
2021-05-20  2:45                       ` Nicholas Piggin
2021-05-20  2:45                         ` Nicholas Piggin
2021-05-20  2:59                         ` Dmitry V. Levin
2021-05-20  2:59                           ` Dmitry V. Levin
2021-05-20  7:20                           ` Nicholas Piggin
2021-05-20  7:20                             ` Nicholas Piggin

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=20210518231331.GA8464@altlinux.org \
    --to=ldv@altlinux.org \
    --cc=libc-dev@lists.llvm.org \
    --cc=linux-api@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    --cc=musl@lists.openwall.com \
    --cc=npiggin@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.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.