From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 59AC7BA45 for ; Tue, 7 Mar 2023 17:56:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D0821C433D2; Tue, 7 Mar 2023 17:56:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1678211766; bh=RXXBY/6yfiWKShcR8orx+uf1enEGD2NB1ekCpIGH6os=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VpcdOm7GbtRWLLDjP8ymd43hh+xPr9LOgMzwt7yTB3zHQHZ9RWo3zBWQbaqYpyLH0 p7IZdFmwo2p70YNEQ++49tCnXI2ZjkCOXbE6JRjxQglnBoehcom2BKaXjTf/r34iGu AySPpg4RBi73qRRLqe8F867o9g34IweF5fNLI1aw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mattias Nissler , =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , Palmer Dabbelt Subject: [PATCH 6.2 0970/1001] riscv: Avoid enabling interrupts in die() Date: Tue, 7 Mar 2023 18:02:22 +0100 Message-Id: <20230307170104.308025518@linuxfoundation.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230307170022.094103862@linuxfoundation.org> References: <20230307170022.094103862@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Mattias Nissler commit 130aee3fd9981297ff9354e5d5609cd59aafbbea upstream. While working on something else, I noticed that the kernel would start accepting interrupts again after crashing in an interrupt handler. Since the kernel is already in inconsistent state, enabling interrupts is dangerous and opens up risk of kernel state deteriorating further. Interrupts do get enabled via what looks like an unintended side effect of spin_unlock_irq, so switch to the more cautious spin_lock_irqsave/spin_unlock_irqrestore instead. Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code") Signed-off-by: Mattias Nissler Reviewed-by: Björn Töpel Link: https://lore.kernel.org/r/20230215144828.3370316-1-mnissler@rivosinc.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman --- arch/riscv/kernel/traps.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -34,10 +34,11 @@ void die(struct pt_regs *regs, const cha static int die_counter; int ret; long cause; + unsigned long flags; oops_enter(); - spin_lock_irq(&die_lock); + spin_lock_irqsave(&die_lock, flags); console_verbose(); bust_spinlocks(1); @@ -54,7 +55,7 @@ void die(struct pt_regs *regs, const cha bust_spinlocks(0); add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); - spin_unlock_irq(&die_lock); + spin_unlock_irqrestore(&die_lock, flags); oops_exit(); if (in_interrupt())