[tip: sched/rt] printk: Flush nbcon consoles first on panic

[tip-bot2 for John Ogness]

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

Commit-ID:     d2e85ca7a736d2d889bac9aef6ede0a67f6870b2
Gitweb:        https://git.kernel.org/tip/d2e85ca7a736d2d889bac9aef6ede0a67f6870b2
Author:        John Ogness <john.ogness@xxxxxxxxxxxxx>
AuthorDate:    Tue, 20 Aug 2024 08:35:51 +02:06
Committer:     Petr Mladek <pmladek@xxxxxxxx>
CommitterDate: Wed, 21 Aug 2024 14:56:24 +02:00

printk: Flush nbcon consoles first on panic

In console_flush_on_panic(), flush the nbcon consoles before
flushing legacy consoles. The legacy write() callbacks are not
fully safe when oops_in_progress is set.

Signed-off-by: John Ogness <john.ogness@xxxxxxxxxxxxx>
Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>
Link: https://lore.kernel.org/r/20240820063001.36405-26-john.ogness@xxxxxxxxxxxxx
Signed-off-by: Petr Mladek <pmladek@xxxxxxxx>
---
 kernel/printk/printk.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 7c9f8f6..c6e6333 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -3269,6 +3269,9 @@ void console_flush_on_panic(enum con_flush_mode mode)
 	if (mode == CONSOLE_REPLAY_ALL)
 		__console_rewind_all();
 
+	if (!have_boot_console)
+		nbcon_atomic_flush_pending();
+
 	console_flush_all(false, &next_seq, &handover);
 }