From 815fb7cad84c73741fceddb43e64a0107c15511e Mon Sep 17 00:00:00 2001 From: John Ogness Date: Fri, 20 Oct 2023 09:52:59 +0000 Subject: [PATCH 123/184] printk: nbcon: Explicitly release ownership on failed emit Until now it was assumed that ownership has been lost when the write_atomic() callback fails. nbcon_emit_next_record() only returns false when ownership has been lost. So explicitly release ownership if write_atomic() fails to be sure. Signed-off-by: John Ogness Signed-off-by: Sebastian Andrzej Siewior --- kernel/printk/nbcon.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/kernel/printk/nbcon.c b/kernel/printk/nbcon.c index b96077152f49..560d3c478ac1 100644 --- a/kernel/printk/nbcon.c +++ b/kernel/printk/nbcon.c @@ -927,14 +927,18 @@ static bool nbcon_emit_next_record(struct nbcon_write_context *wctxt) if (con->write_atomic) { done = con->write_atomic(con, wctxt); } else { - nbcon_context_release(ctxt); WARN_ON_ONCE(1); done = false; } - /* If not done, the emit was aborted. */ - if (!done) + if (!done) { + /* + * The emit was aborted. This may have been due to a loss + * of ownership. Explicitly release ownership to be sure. + */ + nbcon_context_release(ctxt); return false; + } /* * Since any dropped message was successfully output, reset the -- 2.34.1