Li RongQing 9544f9e694 hung_task: panic when there are more than N hung tasks at the same time ...

The hung_task_panic sysctl is currently a blunt instrument: it's all or
nothing.

Panicking on a single hung task can be an overreaction to a transient
glitch.  A more reliable indicator of a systemic problem is when
multiple tasks hang simultaneously.

Extend hung_task_panic to accept an integer threshold, allowing the
kernel to panic only when N hung tasks are detected in a single scan. 
This provides finer control to distinguish between isolated incidents
and system-wide failures.

The accepted values are:
- 0: Don't panic (unchanged)
- 1: Panic on the first hung task (unchanged)
- N > 1: Panic after N hung tasks are detected in a single scan

The original behavior is preserved for values 0 and 1, maintaining full
backward compatibility.

[[email protected]: new changelog]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Li RongQing <[email protected]>
Reviewed-by: Masami Hiramatsu (Google) <[email protected]>
Reviewed-by: Lance Yang <[email protected]>
Tested-by: Lance Yang <[email protected]>
Acked-by: Andrew Jeffery <[email protected]> [aspeed_g5_defconfig]
Cc: Anshuman Khandual <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: Florian Wesphal <[email protected]>
Cc: Jakub Kacinski <[email protected]>
Cc: Jason A. Donenfeld <[email protected]>
Cc: Joel Granados <[email protected]>
Cc: Joel Stanley <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Liam Howlett <[email protected]>
Cc: Lorenzo Stoakes <[email protected]>
Cc: "Paul E . McKenney" <[email protected]>
Cc: Pawan Gupta <[email protected]>
Cc: Petr Mladek <[email protected]>
Cc: Phil Auld <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Russell King <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Simon Horman <[email protected]>
Cc: Stanislav Fomichev <[email protected]>
Cc: Steven Rostedt <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

2025-11-12 10:00:14 -08:00

..

debug.config

hung_task: panic when there are more than N hung tasks at the same time

2025-11-12 10:00:14 -08:00

hardening.config

kcfi: Rename CONFIG_CFI_CLANG to CONFIG_CFI

2025-09-24 14:29:14 -07:00

kvm_guest.config

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nopm.config

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rust.config

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tiny-base.config

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tiny.config

tinyconfig: enable CONFIG_LD_DEAD_CODE_DATA_ELIMINATION

2025-06-06 05:40:24 +09:00

x86_debug.config

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xen.config

xen: enable XEN_UNPOPULATED_ALLOC as part of xen.config

2025-05-23 07:07:09 +02:00