From: Jay Wang <wanjay@amazon.com>
To: <sashiko-bot@kernel.org>
Cc: <bpf@vger.kernel.org>, <linux-modules@vger.kernel.org>
Subject: Re: [PATCH bpf-next v2 9/9] kbuild, bpf: allow building the vmlinux BTF as a module
Date: Fri, 25 Sep 2026 23:02:52 +0000 [thread overview]
Message-ID: <20260925230252.34602-1-wanjay@amazon.com> (raw)
In-Reply-To: <20260925213305.A7C371F000FF@smtp.kernel.org>
For "depends on DEBUG_INFO_BTF" this does not happen: Kconfig turns an
m upper bound into y for a bool symbol (scripts/kconfig/symbol.c,
sym_calc_visibility()). I checked it with olddefconfig: with
SCHED_CLASS_EXT, NET_SCH_BPF, PROBE_EVENTS_BTF_ARGS, BINFMT_MISC_BPF,
IO_URING_BPF_OPS and DEBUG_INFO_BTF_MODULES enabled, switching
DEBUG_INFO_BTF from y to m changes nothing but BPF_PRELOAD, which the
series excludes on purpose.
Looking at the other uses turned up the reverse case, though: RUST and
GENDWARFKSYMS say "depends on !DEBUG_INFO_BTF", and !m is m, which a
bool again takes as y, so with =m those pahole restrictions no longer
applied. v3 writes them as DEBUG_INFO_BTF=n (patch 8/9):
https://lore.kernel.org/bpf/20260925224229.1850-1-wanjay@amazon.com/
Jay
prev parent reply other threads:[~2026-09-25 23:02 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-09-25 21:13 [PATCH bpf-next v2 0/9] bpf: make the vmlinux BTF an on-demand loadable module (CONFIG_DEBUG_INFO_BTF=m) to save ~5.4 MB memory Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 1/9] bpf: pass the vmlinux BTF to btf_parse_module() and let it adopt the data Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 2/9] bpf: split the kfunc, dtor kfunc and struct_ops registration bodies Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 3/9] bpf: fetch the vmlinux BTF where kernel types enter a program Jay Wang
2026-09-25 21:42 ` sashiko-bot
2026-09-25 23:02 ` Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 4/9] bpf: take the vmlinux BTF from the btf_vmlinux module Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 5/9] bpf: defer vmlinux kfunc and struct_ops registrations Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 6/9] bpf: keep module BTF until the vmlinux BTF is available Jay Wang
2026-09-25 21:29 ` sashiko-bot
2026-09-25 23:02 ` Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 7/9] bpf: expose deferred .BTF.base module BTF in sysfs from module load Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 8/9] bpf, trace, net: prepare CONFIG_DEBUG_INFO_BTF checks for a tristate Jay Wang
2026-09-25 21:13 ` [PATCH bpf-next v2 9/9] kbuild, bpf: allow building the vmlinux BTF as a module Jay Wang
2026-09-25 21:33 ` sashiko-bot
2026-09-25 23:02 ` Jay Wang [this message]
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=20260925230252.34602-1-wanjay@amazon.com \
--to=wanjay@amazon.com \
--cc=bpf@vger.kernel.org \
--cc=linux-modules@vger.kernel.org \
--cc=sashiko-bot@kernel.org \
/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.