From 4dd43ee784a1e6b026dc15f7a04a77a3375c5546 Mon Sep 17 00:00:00 2001 From: Mattias Nissler Date: Wed, 15 Feb 2023 14:48:28 +0000 Subject: [PATCH] riscv: Avoid enabling interrupts in die() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit [ Upstream commit 130aee3fd9981297ff9354e5d5609cd59aafbbea ] 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: Sasha Levin --- arch/riscv/kernel/traps.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/riscv/kernel/traps.c b/arch/riscv/kernel/traps.c index 502cba5029ca4..4f38b3c47e6d5 100644 --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -34,10 +34,11 @@ void die(struct pt_regs *regs, const char *str) 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 char *str) 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())