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 7C8151F543F; Tue, 21 Jan 2025 18:07:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737482852; cv=none; b=hz/x1IHbJBa2x/ouygp2aHVDFD7t/OE4cuFkM16oHWD9UCvj67U6wvVsXE5pALqoqGMq0DfAlhbcCzyEJj63KYhfgxXcl3g6Tq5koTWmhO0Fu7gxzOog99lbO/Qr75eZEY77MhoeRf8yhp7IyFeO2tsopiXwQX5QEpDRr1wLkvI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737482852; c=relaxed/simple; bh=1xVD8KAgdgcRC/ErQDJHCHL7lg/OKD9zrnqEMe0CezQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=V3WToIv6JmnGizVb7aQaf91tC5K9hP0eFLr+F6Du5UOHazWdk/6G6935Fh+R+4UcEIyu+l20OGauTCis0/3p6Ke0ZuvyK3nh5o+50GNTSh/t9NHu03Q+QL3fkMAg/iNSIpO3N/nFXviXUWwbwX9Jqw1TaxcutfrKqQr13L/bGDo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=hLjtYPcn; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="hLjtYPcn" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8C85FC4CEDF; Tue, 21 Jan 2025 18:07:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1737482852; bh=1xVD8KAgdgcRC/ErQDJHCHL7lg/OKD9zrnqEMe0CezQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hLjtYPcnDK6dtRRhYqvkUXXNqquDnBQ4/qkoE84hgakdsyLTApXsnjmMiFmye+iTY FJ5JPLtSZKgG5h3qMXJngkxNikxsejBM4jISA9ts0oqgNB4r63lY/S+EWrImk1bhGG 9tTHTfm1SS3lUTt8DeZVg4acugVSykWoay1UQFf0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Nam Cao , Sebastian Andrzej Siewior , Palmer Dabbelt Subject: [PATCH 5.15 030/127] riscv: Fix sleeping in invalid context in die() Date: Tue, 21 Jan 2025 18:51:42 +0100 Message-ID: <20250121174530.831080839@linuxfoundation.org> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250121174529.674452028@linuxfoundation.org> References: <20250121174529.674452028@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nam Cao commit 6a97f4118ac07cfdc316433f385dbdc12af5025e upstream. die() can be called in exception handler, and therefore cannot sleep. However, die() takes spinlock_t which can sleep with PREEMPT_RT enabled. That causes the following warning: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 285, name: mutex preempt_count: 110001, expected: 0 RCU nest depth: 0, expected: 0 CPU: 0 UID: 0 PID: 285 Comm: mutex Not tainted 6.12.0-rc7-00022-ge19049cf7d56-dirty #234 Hardware name: riscv-virtio,qemu (DT) Call Trace: dump_backtrace+0x1c/0x24 show_stack+0x2c/0x38 dump_stack_lvl+0x5a/0x72 dump_stack+0x14/0x1c __might_resched+0x130/0x13a rt_spin_lock+0x2a/0x5c die+0x24/0x112 do_trap_insn_illegal+0xa0/0xea _new_vmalloc_restore_context_a0+0xcc/0xd8 Oops - illegal instruction [#1] Switch to use raw_spinlock_t, which does not sleep even with PREEMPT_RT enabled. Fixes: 76d2a0493a17 ("RISC-V: Init and Halt Code") Signed-off-by: Nam Cao Cc: stable@vger.kernel.org Reviewed-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20241118091333.1185288-1-namcao@linutronix.de Signed-off-by: Palmer Dabbelt Signed-off-by: Greg Kroah-Hartman --- arch/riscv/kernel/traps.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/arch/riscv/kernel/traps.c +++ b/arch/riscv/kernel/traps.c @@ -27,7 +27,7 @@ int show_unhandled_signals = 1; -static DEFINE_SPINLOCK(die_lock); +static DEFINE_RAW_SPINLOCK(die_lock); void die(struct pt_regs *regs, const char *str) { @@ -38,7 +38,7 @@ void die(struct pt_regs *regs, const cha oops_enter(); - spin_lock_irqsave(&die_lock, flags); + raw_spin_lock_irqsave(&die_lock, flags); console_verbose(); bust_spinlocks(1); @@ -55,7 +55,7 @@ void die(struct pt_regs *regs, const cha bust_spinlocks(0); add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE); - spin_unlock_irqrestore(&die_lock, flags); + raw_spin_unlock_irqrestore(&die_lock, flags); oops_exit(); if (in_interrupt())