From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Song Liu <songliubraving@fb.com>
Cc: Network Development <netdev@vger.kernel.org>,
bpf <bpf@vger.kernel.org>, Kernel Team <kernel-team@fb.com>,
Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
John Fastabend <john.fastabend@gmail.com>,
KP Singh <kpsingh@chromium.org>
Subject: Re: [PATCH v2 bpf-next] bpf: fix raw_tp test run in preempt kernel
Date: Tue, 29 Sep 2020 20:23:58 -0700 [thread overview]
Message-ID: <CAADnVQ+jaUfJkD0POaRyrmrLueVP9x-rN8bcN5eEz4XPBk96bw@mail.gmail.com> (raw)
In-Reply-To: <20200930002011.521337-1-songliubraving@fb.com>
On Tue, Sep 29, 2020 at 5:20 PM Song Liu <songliubraving@fb.com> wrote:
>
> In preempt kernel, BPF_PROG_TEST_RUN on raw_tp triggers:
>
> [ 35.874974] BUG: using smp_processor_id() in preemptible [00000000]
> code: new_name/87
> [ 35.893983] caller is bpf_prog_test_run_raw_tp+0xd4/0x1b0
> [ 35.900124] CPU: 1 PID: 87 Comm: new_name Not tainted 5.9.0-rc6-g615bd02bf #1
> [ 35.907358] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> BIOS 1.10.2-1ubuntu1 04/01/2014
> [ 35.916941] Call Trace:
> [ 35.919660] dump_stack+0x77/0x9b
> [ 35.923273] check_preemption_disabled+0xb4/0xc0
> [ 35.928376] bpf_prog_test_run_raw_tp+0xd4/0x1b0
> [ 35.933872] ? selinux_bpf+0xd/0x70
> [ 35.937532] __do_sys_bpf+0x6bb/0x21e0
> [ 35.941570] ? find_held_lock+0x2d/0x90
> [ 35.945687] ? vfs_write+0x150/0x220
> [ 35.949586] do_syscall_64+0x2d/0x40
> [ 35.953443] entry_SYSCALL_64_after_hwframe+0x44/0xa9
>
> Fix this by calling migrate_disable() before smp_processor_id().
>
> Fixes: 1b4d60ec162f ("bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint")
> Reported-by: Alexei Starovoitov <ast@kernel.org>
> Signed-off-by: Song Liu <songliubraving@fb.com>
>
> ---
> Changes v1 => v2:
> 1. Keep rcu_read_lock/unlock() in original places. (Alexei)
> 2. Use get_cpu() instead of smp_processor_id(). (Alexei)
Applying: bpf: fix raw_tp test run in preempt kernel
Using index info to reconstruct a base tree...
error: patch failed: net/bpf/test_run.c:293
error: net/bpf/test_run.c: patch does not apply
error: Did you hand edit your patch?
next prev parent reply other threads:[~2020-09-30 3:24 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-30 0:20 [PATCH v2 bpf-next] bpf: fix raw_tp test run in preempt kernel Song Liu
2020-09-30 3:23 ` Alexei Starovoitov [this message]
2020-09-30 6:45 ` Song Liu
2020-09-30 15:35 ` Alexei Starovoitov
2020-09-30 15:48 ` Song Liu
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=CAADnVQ+jaUfJkD0POaRyrmrLueVP9x-rN8bcN5eEz4XPBk96bw@mail.gmail.com \
--to=alexei.starovoitov@gmail.com \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=john.fastabend@gmail.com \
--cc=kernel-team@fb.com \
--cc=kpsingh@chromium.org \
--cc=netdev@vger.kernel.org \
--cc=songliubraving@fb.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 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.