kevin/linux
1
Fork 0
Code

printk fixup for 6.11-rc5

Browse Source 
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEESH4wyp42V4tXvYsjUqAMR0iAlPIFAmbDBfYACgkQUqAMR0iA
 lPL3ohAArEJ46nPdGWXEZ+K78biXlz/F3IXT+FH95YgtpIk0Tha6Jc5xybGerf/N
 91GzWGbFweEFIIHq9i/CeBnmUEYsMocDF2hlmPiCvaqvMl1J6EuXgERUaPWqaQTS
 fPZab7x8MitH64hFGWbMbvt8ZDJXyQaixtkQyA0AoRPMTpiQy0mFWbFIhtN9M+Cx
 dov2l4N9je8X46X7SWDdKNvVEXHPnpWpq5NeMr9FW7yM4Kun3Hdb3Ks58sHS2oLm
 EmPFQ6kNuxpHyXNvfjeE/JdXQZvK2gGOCNS4zykpGVYJJvhmfrNSwR7iGhm0z/Zw
 sFObF46fK2NTkD5UZ9jQK8+uTiOwpiZSka8v55LocLa7gg2e1G7owaRSIMKjeNYT
 GVmcdkgLqdtfKo3D3rM+auWXlP9o+ioqM52HCewWzMXd0HC2nLx28X/66oHbif9U
 qJSjDPTtvlVEfIcbLr0bRX9KrYeqwtXD74zxB+msbi3Z2C/O9CrFfnGaI0h6+8cb
 RwAptjiO8QdbKkL06CW5RjM5ulNqtPmRETziwA01gh5h6AE5oR1PHCf0DM12ulYK
 /gY/rMznZ6qK0G+BYQyRhMgZh5P5KPvL77a7kxknuj4va2s6c2EsnG8u5iYcYAdo
 YHWN6Jad1OPfQyHsqQ7IL+zlQzTPKmuy3PHQcZwBezUPWRY96kI=
 =2wc2
 -----END PGP SIGNATURE-----

Merge tag 'printk-for-6.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux

Pull printk fix from Petr Mladek:

 - Do not block printk on non-panic CPUs when they are dumping
   backtraces

* tag 'printk-for-6.11-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
  printk/panic: Allow cpu backtraces to be written into ringbuffer during panic
This commit is contained in:
Linus Torvalds 2024-08-19 09:26:35 -07:00
commit b0da640826
3 changed files with 9 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
include/linux/panic.h
View File

@ -16,6 +16,7 @@ extern void oops_enter(void);
extern void oops_exit(void);
extern bool oops_may_print(void);
extern bool panic_triggering_all_cpu_backtrace;
extern int panic_timeout;
extern unsigned long panic_print;
extern int panic_on_oops;

8
kernel/panic.c
View File

@ -64,6 +64,8 @@ unsigned long panic_on_taint;
bool panic_on_taint_nousertaint = false;
static unsigned int warn_limit __read_mostly;
bool panic_triggering_all_cpu_backtrace;
int panic_timeout = CONFIG_PANIC_TIMEOUT;
EXPORT_SYMBOL_GPL(panic_timeout);
@ -253,8 +255,12 @@ void check_panic_on_warn(const char *origin)
*/
static void panic_other_cpus_shutdown(bool crash_kexec)
{
if (panic_print & PANIC_PRINT_ALL_CPU_BT)
if (panic_print & PANIC_PRINT_ALL_CPU_BT) {
/* Temporary allow non-panic CPUs to write their backtraces. */
panic_triggering_all_cpu_backtrace = true;
trigger_all_cpu_backtrace();
panic_triggering_all_cpu_backtrace = false;
}
/*
* Note that smp_send_stop() is the usual SMP shutdown function,

2
kernel/printk/printk.c
View File

@ -2316,7 +2316,7 @@ asmlinkage int vprintk_emit(int facility, int level,
* non-panic CPUs are generating any messages, they will be
* silently dropped.
*/
if (other_cpu_in_panic())
if (other_cpu_in_panic() && !panic_triggering_all_cpu_backtrace)
return 0;
if (level == LOGLEVEL_SCHED) {