diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 7123524a86b8..6287f6be4a98 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3726,6 +3726,7 @@ bit 3: print locks info if CONFIG_LOCKDEP is on bit 4: print ftrace buffer bit 5: print all printk messages in buffer + bit 6: print all CPUs backtrace (if available in the arch) panic_on_taint= Bitmask for conditionally calling panic() in add_taint() Format: [,nousertaint] diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst index 0f86e9f93129..cfd6c20ce42e 100644 --- a/Documentation/admin-guide/sysctl/kernel.rst +++ b/Documentation/admin-guide/sysctl/kernel.rst @@ -796,6 +796,7 @@ bit 2 print timer info bit 3 print locks info if ``CONFIG_LOCKDEP`` is on bit 4 print ftrace buffer bit 5 print all printk messages in buffer +bit 6 print all CPUs backtrace (if available in the arch) ===== ============================================ So for example to print tasks and memory info on panic, user can:: diff --git a/kernel/panic.c b/kernel/panic.c index 95ba825522dd..3c3fb36d8d41 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -66,6 +66,7 @@ EXPORT_SYMBOL_GPL(panic_timeout); #define PANIC_PRINT_LOCK_INFO 0x00000008 #define PANIC_PRINT_FTRACE_INFO 0x00000010 #define PANIC_PRINT_ALL_PRINTK_MSG 0x00000020 +#define PANIC_PRINT_ALL_CPU_BT 0x00000040 unsigned long panic_print; ATOMIC_NOTIFIER_HEAD(panic_notifier_list); @@ -152,6 +153,9 @@ static void panic_print_sys_info(void) if (panic_print & PANIC_PRINT_ALL_PRINTK_MSG) console_flush_on_panic(CONSOLE_REPLAY_ALL); + if (panic_print & PANIC_PRINT_ALL_CPU_BT) + trigger_all_cpu_backtrace(); + if (panic_print & PANIC_PRINT_TASK_INFO) show_state();