hung_task: panic after fixed number of hung tasks
Currently, when 'hung_task_panic' is enabled, the kernel panics
immediately upon detecting the first hung task. However, some hung tasks
are transient and the system can recover, while others are persistent and
may accumulate progressively.
This patch extends the 'hung_task_panic' sysctl to allow specifying the
number of hung tasks that must be detected before triggering a kernel
panic. This provides finer control for environments where transient hangs
may occur but persistent hangs should still be fatal.
The sysctl can be set to:
- 0: disabled (never panic)
- 1: original behavior (panic on first hung task)
- N: panic when N hung tasks are detected
This maintains backward compatibility while providing more flexibility
for handling different hang scenarios.
Link: https://lkml.kernel.org/r/20251012115035.2169-1-lirongqing@baidu.com
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Cc: Andrew Jeffery <andrew@codeconstruct.com.au>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Florian Wesphal <fw@strlen.de>
Cc: Jakub Kacinski <kuba@kernel.org>
Cc: Jason A. Donenfeld <jason@zx2c4.com>
Cc: Joel Granados <joel.granados@kernel.org>
Cc: Joel Stanley <joel@jms.id.au>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kees Cook <kees@kernel.org>
Cc: Lance Yang <lance.yang@linux.dev>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: "Paul E . McKenney" <paulmck@kernel.org>
Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Simon Horman <horms@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
7 files changed
