From: Segher Boessenkool <segher@kernel.crashing.org>
To: Michael Ellerman <mpe@ellerman.id.au>
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>,
Boqun Feng <boqun.feng@gmail.com>,
Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
Michael Jeanson <mjeanson@efficios.com>
Subject: Re: Failure to build librseq on ppc
Date: Wed, 8 Jul 2020 18:53:31 -0500 [thread overview]
Message-ID: <20200708235331.GA3598@gate.crashing.org> (raw)
In-Reply-To: <87k0ze2nv4.fsf@mpe.ellerman.id.au>
Hi!
On Wed, Jul 08, 2020 at 10:27:27PM +1000, Michael Ellerman wrote:
> Segher Boessenkool <segher@kernel.crashing.org> writes:
> > You'll have to show the actual failing machine code, and with enough
> > context that we can relate this to the source code.
> >
> > -save-temps helps, or use -S instead of -c, etc.
>
> Attached below.
Thanks!
> I think that's from:
>
> #define LOAD_WORD "ld "
>
> #define RSEQ_ASM_OP_CMPEQ(var, expect, label) \
> LOAD_WORD "%%r17, %[" __rseq_str(var) "]\n\t" \
The way this hardcodes r17 *will* break, btw. The compiler will not
likely want to use r17 as long as your code (after inlining etc.!) stays
small, but there is Murphy's law.
Anyway... something in rseq_str is wrong, missing %X<n>. This may
have to do with the abuse of inline asm here, making a fix harder :-(
Segher
next prev parent reply other threads:[~2020-07-08 23:56 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-07-07 19:17 Failure to build librseq on ppc Mathieu Desnoyers
2020-07-08 0:59 ` Segher Boessenkool
2020-07-08 12:27 ` Michael Ellerman
2020-07-08 23:53 ` Segher Boessenkool [this message]
2020-07-09 0:01 ` Mathieu Desnoyers
2020-07-09 0:18 ` Segher Boessenkool
2020-07-09 13:43 ` Mathieu Desnoyers
2020-07-09 17:37 ` Segher Boessenkool
2020-07-09 17:42 ` Mathieu Desnoyers
2020-07-09 17:56 ` Mathieu Desnoyers
2020-07-09 20:46 ` Segher Boessenkool
2020-07-09 20:57 ` Mathieu Desnoyers
2020-07-09 20:31 ` Segher Boessenkool
2020-07-08 12:33 ` Mathieu Desnoyers
2020-07-08 14:00 ` Mathieu Desnoyers
2020-07-08 14:21 ` Christophe Leroy
2020-07-08 14:32 ` Mathieu Desnoyers
2020-07-08 16:11 ` Christophe Leroy
2020-07-09 0:15 ` Segher Boessenkool
2020-07-09 0:10 ` Segher Boessenkool
2020-07-09 13:33 ` Mathieu Desnoyers
2020-07-09 17:31 ` Segher Boessenkool
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=20200708235331.GA3598@gate.crashing.org \
--to=segher@kernel.crashing.org \
--cc=boqun.feng@gmail.com \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mathieu.desnoyers@efficios.com \
--cc=mjeanson@efficios.com \
--cc=mpe@ellerman.id.au \
/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).