diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2024-03-22 02:14:13 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-03-22 02:15:08 +0300 |
| commit | 537c2e91d3549e5d6020bb0576cf9b54a845255f (patch) | |
| tree | c09e8a1b7d733cde19b0c72678c28fb2bc97ff6b /lib/dump_stack.c | |
| parent | 237bb5f7f7f55ec5f773469a974c61a49c298625 (diff) | |
| parent | cba9ffdb9913dfe6be29f049ce920ce451ce7cc4 (diff) | |
| download | linux-537c2e91d3549e5d6020bb0576cf9b54a845255f.tar.xz | |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'lib/dump_stack.c')
| -rw-r--r-- | lib/dump_stack.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/lib/dump_stack.c b/lib/dump_stack.c index 83471e81501a..222c6d6c8281 100644 --- a/lib/dump_stack.c +++ b/lib/dump_stack.c @@ -96,15 +96,25 @@ static void __dump_stack(const char *log_lvl) */ asmlinkage __visible void dump_stack_lvl(const char *log_lvl) { + bool in_panic = this_cpu_in_panic(); unsigned long flags; /* * Permit this cpu to perform nested stack dumps while serialising - * against other CPUs + * against other CPUs, unless this CPU is in panic. + * + * When in panic, non-panic CPUs are not permitted to store new + * printk messages so there is no need to synchronize the output. + * This avoids potential deadlock in panic() if another CPU is + * holding and unable to release the printk_cpu_sync. */ - printk_cpu_sync_get_irqsave(flags); + if (!in_panic) + printk_cpu_sync_get_irqsave(flags); + __dump_stack(log_lvl); - printk_cpu_sync_put_irqrestore(flags); + + if (!in_panic) + printk_cpu_sync_put_irqrestore(flags); } EXPORT_SYMBOL(dump_stack_lvl); |