From: "H.J. Lu" <hjl.tools@gmail.com>
To: Jan Beulich <jbeulich@suse.com>
Cc: binutils@sourceware.org
Subject: Re: [PATCH] x86: Warn .insn instruction with length > 15 bytes
Date: Tue, 6 Feb 2024 03:36:06 -0800 [thread overview]
Message-ID: <CAMe9rOo+tdStFmPbOVVctBe0SzDjkoqjU_xn+wa5gCpQSSh97A@mail.gmail.com> (raw)
In-Reply-To: <4b1c3da8-d218-460b-89e6-6844096ed393@suse.com>
On Tue, Feb 6, 2024 at 12:19 AM Jan Beulich <jbeulich@suse.com> wrote:
>
> On 05.02.2024 21:00, H.J. Lu wrote:
> > Change .insn instruction with length > 15 bytes from error to warning.
>
> Thanks for doing this. FTAOD though - it addresses only half of my
> concern. Besides .insn (where the concern was of general nature) I
> also use
>
> bextr eax, fs:[eax*4], 0x11223344
> xacquire lock add qword ptr gs:[eax*8], 0x11223344
>
> in testing of my own disassembler library. I expect to continue to
> be able to avoid using .insn (and even more so .byte) when assembling
> this code. IOW there will still need to be a way to also override
> the defaulting to as_bad() when not using .insn.
We issue a warning when something is wrong in input, but still manage
to generate an instruction. This is an error case.
> > --- a/gas/config/tc-i386.c
> > +++ b/gas/config/tc-i386.c
> > @@ -11780,8 +11780,14 @@ output_insn (const struct last_insn *last_insn)
> > {
> > j = encoding_length (insn_start_frag, insn_start_off, frag_more (0));
> > if (j > 15)
> > - as_bad (_("instruction length of %u bytes exceeds the limit of 15"),
> > - j);
> > + {
> > + if (i.tm.mnem_off == MN__insn)
>
> Please don't open-code dot_insn().
>
Fixed in v2.
--
H.J.
next prev parent reply other threads:[~2024-02-06 11:36 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-02-05 20:00 H.J. Lu
2024-02-06 8:19 ` Jan Beulich
2024-02-06 11:36 ` H.J. Lu [this message]
2024-02-06 11:41 ` Jan Beulich
2024-02-06 12:26 ` H.J. Lu
2024-02-06 14:43 ` Michael Matz
2024-02-06 14:49 ` H.J. Lu
2024-02-06 15:04 ` Michael Matz
2024-02-06 15:34 ` H.J. Lu
2024-02-06 15:48 ` Michael Matz
2024-02-06 16:28 ` H.J. Lu
2024-02-06 17:05 ` Jan Beulich
2024-02-06 18:06 ` H.J. Lu
2024-02-07 7:51 ` Jan Beulich
2024-02-07 15:24 ` H.J. Lu
2024-02-07 15:32 ` Jan Beulich
2024-02-07 16:53 ` H.J. Lu
2024-02-07 16:59 ` Jan Beulich
2024-02-07 17:03 ` H.J. Lu
2024-02-08 4:09 ` Jiang, Haochen
2024-02-08 4:47 ` Hongyu Wang
2024-02-08 8:15 ` Jan Beulich
2024-02-08 8:23 ` Jan Beulich
2024-02-08 11:38 ` H.J. Lu
2024-02-08 6:26 ` Sunil Pandey
2024-02-08 6:41 ` Cui, Lili
2024-02-08 8:18 ` Jan Beulich
2024-02-08 11:31 ` H.J. Lu
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=CAMe9rOo+tdStFmPbOVVctBe0SzDjkoqjU_xn+wa5gCpQSSh97A@mail.gmail.com \
--to=hjl.tools@gmail.com \
--cc=binutils@sourceware.org \
--cc=jbeulich@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 read-only IMAP folder(s) and NNTP newsgroup(s).