[tip: sched/rt] panic: Mark emergency section in warn

[tip-bot2 for Thomas Gleixner]

The following commit has been merged into the sched/rt branch of tip:

Commit-ID:     4833794db61c8cc4de4563a2754c7aedaffbb684
Gitweb:        https://git.kernel.org/tip/4833794db61c8cc4de4563a2754c7aedaffbb684
Author:        Thomas Gleixner <tglx@xxxxxxxxxxxxx>
AuthorDate:    Tue, 20 Aug 2024 08:35:58 +02:06
Committer:     Petr Mladek <pmladek@xxxxxxxx>
CommitterDate: Wed, 21 Aug 2024 15:03:04 +02:00

panic: Mark emergency section in warn

Mark the full contents of __warn() as an emergency section. In
this section, every printk() call will attempt to directly
flush to the consoles using the EMERGENCY priority.

Co-developed-by: John Ogness <john.ogness@xxxxxxxxxxxxx>
Signed-off-by: John Ogness <john.ogness@xxxxxxxxxxxxx>
Signed-off-by: Thomas Gleixner (Intel) <tglx@xxxxxxxxxxxxx>
Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
Link: https://lore.kernel.org/r/20240820063001.36405-33-john.ogness@xxxxxxxxxxxxx
Signed-off-by: Petr Mladek <pmladek@xxxxxxxx>
---
 kernel/panic.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/kernel/panic.c b/kernel/panic.c
index 93096d5..1a10b6e 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -718,6 +718,8 @@ struct warn_args {
 void __warn(const char *file, int line, void *caller, unsigned taint,
 	    struct pt_regs *regs, struct warn_args *args)
 {
+	nbcon_cpu_emergency_enter();
+
 	disable_trace_on_warning();
 
 	if (file)
@@ -753,6 +755,8 @@ void __warn(const char *file, int line, void *caller, unsigned taint,
 
 	/* Just a warning, don't kill lockdep. */
 	add_taint(taint, LOCKDEP_STILL_OK);
+
+	nbcon_cpu_emergency_exit();
 }
 
 #ifdef CONFIG_BUG