linux-stable.git/tools/testing/selftests/bpf/progs/timer_start_deadlock.c, branch master Linux kernel stable tree selftests/bpf: Fix timer_start_deadlock failure due to hrtimer change 2026-04-15T15:25:04+00:00 Shung-Hsi Yu shung-hsi.yu@suse.com 2026-04-15T12:03:28+00:00 813f336269e629da5d9c86a8098d6bee3d84680e Since commit f2e388a019e4 ("hrtimer: Reduce trace noise in hrtimer_start()"), hrtimer_cancel tracepoint is no longer called when a hrtimer is re-armed. So instead of a hrtimer_cancel followed by hrtimer_start tracepoint events, there is now only a since hrtimer_start tracepoint event with the new was_armed field set to 1, to indicated that the hrtimer was previously armed. Update timer_start_deadlock accordingly so it traces hrtimer_start tracepoint instead, with was_armed used as guard. Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Tested-by: Mykyta Yatsenko <yatsenko@meta.com> Acked-by: Mykyta Yatsenko <yatsenko@meta.com> Link: https://lore.kernel.org/r/20260415120329.129192-1-shung-hsi.yu@suse.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> 
Since commit f2e388a019e4 ("hrtimer: Reduce trace noise in hrtimer_start()"),
hrtimer_cancel tracepoint is no longer called when a hrtimer is re-armed. So
instead of a hrtimer_cancel followed by hrtimer_start tracepoint events, there
is now only a since hrtimer_start tracepoint event with the new was_armed field
set to 1, to indicated that the hrtimer was previously armed.

Update timer_start_deadlock accordingly so it traces hrtimer_start tracepoint
instead, with was_armed used as guard.

Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Tested-by: Mykyta Yatsenko <yatsenko@meta.com>
Acked-by: Mykyta Yatsenko <yatsenko@meta.com>
Link: https://lore.kernel.org/r/20260415120329.129192-1-shung-hsi.yu@suse.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
selftests/bpf: Strengthen timer_start_deadlock test 2026-02-04T21:12:50+00:00 Alexei Starovoitov ast@kernel.org 2026-02-04T05:51:47+00:00 6e65cf81accf908d2480739b85dba4731048290d Strengthen timer_start_deadlock test and check for recursion now Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260204055147.54960-5-alexei.starovoitov@gmail.com 
Strengthen timer_start_deadlock test and check for recursion now

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260204055147.54960-5-alexei.starovoitov@gmail.com
selftests/bpf: Add a testcase for deadlock avoidance 2026-02-04T21:12:50+00:00 Alexei Starovoitov ast@kernel.org 2026-02-04T05:51:45+00:00 67ee5ad27d5101be4e9e8980c0734a0423bfd0a7 Add a testcase that checks that deadlock avoidance is working as expected. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260204055147.54960-3-alexei.starovoitov@gmail.com 
Add a testcase that checks that deadlock avoidance is working
as expected.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20260204055147.54960-3-alexei.starovoitov@gmail.com