• Song Liu's avatar
    bpf: fix raw_tp test run in preempt kernel · 963ec27a
    Song Liu authored
    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: 1b4d60ec ("bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint")
    Reported-by: default avatarAlexei Starovoitov <ast@kernel.org>
    Signed-off-by: default avatarSong Liu <songliubraving@fb.com>
    Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
    963ec27a
test_run.c 17.8 KB