linux/tools/testing
Li RongQing e700f5d156 watchdog: softlockup: panic when lockup duration exceeds N thresholds
The softlockup_panic sysctl is currently a binary option: panic
immediately or never panic on soft lockups.

Panicking on any soft lockup, regardless of duration, can be overly
aggressive for brief stalls that may be caused by legitimate operations. 
Conversely, never panicking may allow severe system hangs to persist
undetected.

Extend softlockup_panic to accept an integer threshold, allowing the
kernel to panic only when the normalized lockup duration exceeds N
watchdog threshold periods.  This provides finer-grained control to
distinguish between transient delays and persistent system failures.

The accepted values are:
- 0: Don't panic (unchanged)
- 1: Panic when duration >= 1 * threshold (20s default, original behavior)
- N > 1: Panic when duration >= N * threshold (e.g., 2 = 40s, 3 = 60s.)

The original behavior is preserved for values 0 and 1, maintaining full
backward compatibility while allowing systems to tolerate brief lockups
while still catching severe, persistent hangs.

[lirongqing@baidu.com: v2]
  Link: https://lkml.kernel.org/r/20251218074300.4080-1-lirongqing@baidu.com
Link: https://lkml.kernel.org/r/20251216074521.2796-1-lirongqing@baidu.com
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-01-20 19:44:20 -08:00
..
crypto/chacha20-s390
cxl cxl: Check for invalid addresses returned from translation functions on errors 2026-01-13 08:30:40 -07:00
fault-injection
ktest ktest.pl: Fix uninitialized var in config-bisect.pl 2025-12-03 18:25:18 -05:00
kunit kunit: qemu_configs: Add MIPS configurations 2025-09-15 10:30:07 -06:00
memblock
nvdimm tools/testing/nvdimm: Use per-DIMM device handle 2025-11-03 16:47:13 -06:00
radix-tree idr: fix idr_alloc() returning an ID out of range 2025-12-23 11:23:11 -08:00
rbtree
scatterlist mm: remove nth_page() 2025-09-21 14:22:10 -07:00
selftests watchdog: softlockup: panic when lockup duration exceeds N thresholds 2026-01-20 19:44:20 -08:00
shared Summary of significant series in this pull request: 2025-10-02 18:18:33 -07:00
vma mm: introduce VMA flags bitmap type 2025-11-29 10:41:09 -08:00
vsock vsock/test: add a final full barrier after run all tests 2026-01-10 12:07:25 -08:00