linux-kernel - [PATCH -next] hexagon: Fix unbalanced spinlock in die()

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Date:   Mon, 22 May 2023 02:56:08 +0000
From:   Lin Yujun <linyujun809@...wei.com>
To:     <bcain@...cinc.com>, <linyujun809@...wei.com>,
        <linas@...eaurora.org>, <rkuo@...eaurora.org>, <arnd@...db.de>
CC:     <linux-hexagon@...r.kernel.org>, <linux-kernel@...r.kernel.org>
Subject: [PATCH -next] hexagon: Fix unbalanced spinlock in die()

die executes holding the spinlock of &die.lock and unlock
it after printing the oops message.
However in the code if the notify_die() returns NOTIFY_STOP
, die() exit with returning 1 but never unlocked the spinlock.

Fix this by adding spin_unlock_irq(&die.lock) before returning.

Fixes: cf9750bae262 ("Hexagon: Provide basic debugging and system trap support.")
Signed-off-by: Lin Yujun <linyujun809@...wei.com>
---
 arch/hexagon/kernel/traps.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/hexagon/kernel/traps.c b/arch/hexagon/kernel/traps.c
index 6447763ce5a9..b7e394cebe20 100644
--- a/arch/hexagon/kernel/traps.c
+++ b/arch/hexagon/kernel/traps.c
@@ -195,8 +195,10 @@ int die(const char *str, struct pt_regs *regs, long err)
 	printk(KERN_EMERG "Oops: %s[#%d]:\n", str, ++die.counter);
 
 	if (notify_die(DIE_OOPS, str, regs, err, pt_cause(regs), SIGSEGV) ==
-	    NOTIFY_STOP)
+	    NOTIFY_STOP) {
+		spin_unlock_irq(&die.lock);
 		return 1;
+	}
 
 	print_modules();
 	show_regs(regs);
-- 
2.34.1