From: Qiliang Yuan <odys.yuan@gmail.com>
To: bot+bpf-ci@kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
John Fastabend <john.fastabend@gmail.com>,
Andrii Nakryiko <andrii@kernel.org>,
Eduard Zingerman <eddyz87@gmail.com>,
Kumar Kartikeya Dwivedi <memxor@gmail.com>,
Martin KaFai Lau <martin.lau@linux.dev>,
martin.lau@kernel.org, Song Liu <song@kernel.org>,
Yonghong Song <yonghong.song@linux.dev>,
Jiri Olsa <jolsa@kernel.org>,
Emil Tsalapatis <emil@etsalapatis.com>,
Ihor Solodrai <ihor.solodrai@linux.dev>,
Shuah Khan <shuah@kernel.org>,
mason@kernel.org, bpf@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH bpf-next 2/4] bpf: Queue the rewrites of bpf_do_misc_fixups() and apply them at once
Date: Fri, 2 Oct 2026 21:25:16 +0800 [thread overview]
Message-ID: <20261002132516.4109511-1-odys.yuan@gmail.com> (raw)
In-Reply-To: <4b74d8c73be2889b1c85c0b9819dbb7c83c535c46342b7ed11412763abda70b9@mail.kernel.org>
> Take a backward may_goto whose grown offset is exactly -32768 (S16_MIN).
[...]
> Should the JEQ-or-gotol decision be deferred until the final offsets are
> known?
This is a real regression, and it is wider than one displacement: any
backward may_goto whose offset fits in s16 before the patches between
its target and itself are applied, but not after, now gets a JEQ and
fails at commit. Those patches are already queued when the loop
reaches the may_goto, so v2 will add their growth to the offset before
may_goto_expand() picks the encoding, which gives the old choice, and
add a selftest around the boundary.
next prev parent reply other threads:[~2026-10-02 13:25 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-10-01 9:35 [PATCH bpf-next 0/4] bpf: Apply the rewrites of bpf_do_misc_fixups() " Qiliang Yuan
2026-10-01 9:35 ` [PATCH bpf-next 1/4] bpf: Add a list of deferred instruction patches Qiliang Yuan
2026-10-01 10:27 ` bot+bpf-ci
2026-10-01 9:35 ` [PATCH bpf-next 2/4] bpf: Queue the rewrites of bpf_do_misc_fixups() and apply them at once Qiliang Yuan
2026-10-01 10:27 ` bot+bpf-ci
2026-10-02 13:25 ` Qiliang Yuan [this message]
2026-10-01 9:35 ` [PATCH bpf-next 3/4] bpf: Drop the constant delta from bpf_do_misc_fixups() Qiliang Yuan
2026-10-01 9:35 ` [PATCH bpf-next 4/4] selftests/bpf: Test jumps around patches of bpf_do_misc_fixups() Qiliang Yuan
2026-10-02 11:39 ` [PATCH bpf-next 0/4] bpf: Apply the rewrites of bpf_do_misc_fixups() at once Alexei Starovoitov
2026-10-02 13:25 ` Qiliang Yuan
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=20261002132516.4109511-1-odys.yuan@gmail.com \
--to=odys.yuan@gmail.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bot+bpf-ci@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=eddyz87@gmail.com \
--cc=emil@etsalapatis.com \
--cc=ihor.solodrai@linux.dev \
--cc=john.fastabend@gmail.com \
--cc=jolsa@kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=martin.lau@kernel.org \
--cc=martin.lau@linux.dev \
--cc=mason@kernel.org \
--cc=memxor@gmail.com \
--cc=shuah@kernel.org \
--cc=song@kernel.org \
--cc=yonghong.song@linux.dev \
/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
all inboxes | Powered by JetHome®