X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=kernel%2Fprintk.c;h=bdd4ea8c3f2b67520c1a55e0ba34a0a247d350fc;hb=562954d5e01d08154cf15c7e12e6e9ec803f50f7;hp=c46a20a19a153f06e938d469bf760ee893b63114;hpb=8c178beeb20ce3801c4851d41342d0ca32ad292c;p=linux-2.6

diff --git a/kernel/printk.c b/kernel/printk.c
index c46a20a19a..bdd4ea8c3f 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -643,8 +643,21 @@ static int acquire_console_semaphore_for_printk(unsigned int cpu)
 {
 	int retval = 0;
 
-	if (can_use_console(cpu))
-		retval = !try_acquire_console_sem();
+	if (!try_acquire_console_sem()) {
+		retval = 1;
+
+		/*
+		 * If we can't use the console, we need to release
+		 * the console semaphore by hand to avoid flushing
+		 * the buffer. We need to hold the console semaphore
+		 * in order to do this test safely.
+		 */
+		if (!can_use_console(cpu)) {
+			console_locked = 0;
+			up(&console_sem);
+			retval = 0;
+		}
+	}
 	printk_cpu = UINT_MAX;
 	spin_unlock(&logbuf_lock);
 	return retval;