From: Clark Williams <williams@redhat.com>
To: Wander Lairson Costa <wander@redhat.com>
Cc: linux-rt-users@vger.kernel.org,
Derek Barbosa <debarbos@redhat.com>,
John Kacur <jkacur@redhat.com>,
Juri Lelli <juri.lelli@redhat.com>,
Chunsheng Luo <luochunsheng@ustc.edu>
Subject: Re: [PATCH] bpf: Add BPF CO-RE compatibility for older kernels
Date: Tue, 4 Nov 2025 13:57:14 -0600 [thread overview]
Message-ID: <aQpamuow4ucROOAK@lysander> (raw)
In-Reply-To: <20251104141144.31173-1-wander@redhat.com>
On Tue, Nov 04, 2025 at 11:11:44AM -0300, Wander Lairson Costa wrote:
> Introduce a `thread_info___legacy` struct to provide BPF CO-RE
> compatibility for older kernels (e.g., RHEL 8.x with 4.18) where the
> `thread_info` struct lacks the `cpu` field. This allows `bpf_core_field_exists()`
> checks to correctly determine the availability of this field at runtime,
> preventing build failures on such systems.
>
> The `task_cpu` helper function is updated to utilize this new legacy
> struct when accessing the `cpu` field from `thread_info`, ensuring
> that the BPF program can adapt to different kernel versions.
>
> Signed-off-by: Wander Lairson Costa <wander@redhat.com>
> Cc: Derek Barbosa <debarbos@redhat.com>
> Cc: John Kacur <jkacur@redhat.com>
> Cc: Juri Lelli <juri.lelli@redhat.com>
> Cc: Chunsheng Luo <luochunsheng@ustc.edu>
Applied to my devel branch along with the BPF verbose patch to the
Makefile. I'm assembling the v1.25.1 release which will be these two
changes and the current test-suite. Hopefully will go out today or
tomorrow.
Clark
--
The United States Coast Guard
Ruining Natural Selection since 1790
prev parent reply other threads:[~2025-11-04 19:57 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-11-04 14:11 [PATCH] bpf: Add BPF CO-RE compatibility for older kernels Wander Lairson Costa
2025-11-04 19:57 ` Clark Williams [this message]
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