From nobody Wed Sep 17 09:05:00 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 710FDC4167B for ; Wed, 21 Dec 2022 07:43:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234126AbiLUHnF (ORCPT ); Wed, 21 Dec 2022 02:43:05 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35286 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234210AbiLUHnB (ORCPT ); Wed, 21 Dec 2022 02:43:01 -0500 Received: from loongson.cn (mail.loongson.cn [114.242.206.163]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 6772120F40 for ; Tue, 20 Dec 2022 23:43:00 -0800 (PST) Received: from loongson.cn (unknown [111.9.175.10]) by gateway (Coremail) with SMTP id _____8Bx2+oDuaJjn4gHAA--.17081S3; Wed, 21 Dec 2022 15:42:59 +0800 (CST) Received: from localhost.localdomain (unknown [111.9.175.10]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxPuQCuaJj+00GAA--.25824S2; Wed, 21 Dec 2022 15:42:58 +0800 (CST) From: Jinyang He To: Huacai Chen , WANG Xuerui Cc: Tiezhu Yang , loongarch@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH] LoongArch: Fix irq enable in exception handlers Date: Wed, 21 Dec 2022 15:42:38 +0800 Message-Id: <20221221074238.6699-1-hejinyang@loongson.cn> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: AQAAf8CxPuQCuaJj+00GAA--.25824S2 X-CM-SenderInfo: pkhmx0p1dqwqxorr0wxvrqhubq/ X-Coremail-Antispam: 1Uk129KBjvJXoWxGFy8CF48WrW7tr1xWr18uFg_yoWrWrWrpF W7CFs7GrW8C3Z7Wa9rJ34Ivr13X392qay7C3ykC3yfua1ayrykWr1vqFW7XF1jv34Dury0 vryYy3WIq3WUAFUanT9S1TB71UUUUUDqnTZGkaVYY2UrUUUUj1kv1TuYvTs0mT0YCTnIWj qI5I8CrVACY4xI64kE6c02F40Ex7xfYxn0WfASr-VFAUDa7-sFnT9fnUUIcSsGvfJTRUUU b7AYFVCjjxCrM7AC8VAFwI0_Jr0_Gr1l1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s 1l1IIY67AEw4v_Jrv_JF1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xv wVC0I7IYx2IY67AKxVW8JVW5JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwA2z4 x0Y4vEx4A2jsIE14v26r4UJVWxJr1l84ACjcxK6I8E87Iv6xkF7I0E14v26r4UJVWxJr1l e2I262IYc4CY6c8Ij28IcVAaY2xG8wAqjxCEc2xF0cIa020Ex4CE44I27wAqx4xG64xvF2 IEw4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_JF0_Jw1lYx0Ex4A2jsIE14v26r1j6r4U McvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwCF04k20xvY0x0EwIxGrwCFx2 IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480Y4vE14v2 6r106r1rMI8E67AF67kF1VAFwI0_JF0_Jw1lIxkGc2Ij64vIr41lIxAIcVC0I7IYx2IY67 AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Jr0_Gr1lIxAIcVCF04k26cxKx2IY s7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxVAFwI0_Jr 0_GrUvcSsGvfC2KfnxnUUI43ZEXa7IU82g43UUUUU== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The interrupt state can be got by regs->csr_prmd. Once previous interrupt state is disable, we shouldn't enable interrupt if we triggered exception which can be triggered in kernel mode. So conditionally enable interrupt. For those do_\exception which can not triggered in kernel mode but need enable interrupt, call die_if_kernel() firstly. And for do_lsx, do_lasx and do_lbt cannot triggered in kernel mode, too. Signed-off-by: Jinyang He Tested-by: Tiezhu Yang --- arch/loongarch/kernel/traps.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/arch/loongarch/kernel/traps.c b/arch/loongarch/kernel/traps.c index 1ea14f6c18d3..3ac7b32d1e15 100644 --- a/arch/loongarch/kernel/traps.c +++ b/arch/loongarch/kernel/traps.c @@ -340,9 +340,9 @@ asmlinkage void noinstr do_fpe(struct pt_regs *regs, un= signed long fcsr) =20 /* Clear FCSR.Cause before enabling interrupts */ write_fcsr(LOONGARCH_FCSR0, fcsr & ~mask_fcsr_x(fcsr)); - local_irq_enable(); =20 die_if_kernel("FP exception in kernel code", regs); + local_irq_enable(); =20 sig =3D SIGFPE; fault_addr =3D (void __user *) regs->csr_era; @@ -432,7 +432,8 @@ asmlinkage void noinstr do_bp(struct pt_regs *regs) unsigned long era =3D exception_era(regs); irqentry_state_t state =3D irqentry_enter(regs); =20 - local_irq_enable(); + if (regs->csr_prmd & CSR_PRMD_PIE) + local_irq_enable(); current->thread.trap_nr =3D read_csr_excode(); if (__get_inst(&opcode, (u32 *)era, user)) goto out_sigsegv; @@ -514,7 +515,8 @@ asmlinkage void noinstr do_ri(struct pt_regs *regs) unsigned int __user *era =3D (unsigned int __user *)exception_era(regs); irqentry_state_t state =3D irqentry_enter(regs); =20 - local_irq_enable(); + if (regs->csr_prmd & CSR_PRMD_PIE) + local_irq_enable(); current->thread.trap_nr =3D read_csr_excode(); =20 if (notify_die(DIE_RI, "RI Fault", regs, 0, current->thread.trap_nr, @@ -606,8 +608,8 @@ asmlinkage void noinstr do_fpu(struct pt_regs *regs) { irqentry_state_t state =3D irqentry_enter(regs); =20 - local_irq_enable(); die_if_kernel("do_fpu invoked from kernel context!", regs); + local_irq_enable(); BUG_ON(is_lsx_enabled()); BUG_ON(is_lasx_enabled()); =20 @@ -623,13 +625,13 @@ asmlinkage void noinstr do_lsx(struct pt_regs *regs) { irqentry_state_t state =3D irqentry_enter(regs); =20 + die_if_kernel("do_lsx invoked from kernel context!", regs); local_irq_enable(); if (!cpu_has_lsx) { force_sig(SIGILL); goto out; } =20 - die_if_kernel("do_lsx invoked from kernel context!", regs); BUG_ON(is_lasx_enabled()); =20 preempt_disable(); @@ -645,14 +647,13 @@ asmlinkage void noinstr do_lasx(struct pt_regs *regs) { irqentry_state_t state =3D irqentry_enter(regs); =20 + die_if_kernel("do_lasx invoked from kernel context!", regs); local_irq_enable(); if (!cpu_has_lasx) { force_sig(SIGILL); goto out; } =20 - die_if_kernel("do_lasx invoked from kernel context!", regs); - preempt_disable(); init_restore_lasx(); preempt_enable(); @@ -666,6 +667,7 @@ asmlinkage void noinstr do_lbt(struct pt_regs *regs) { irqentry_state_t state =3D irqentry_enter(regs); =20 + die_if_kernel("do_lbt invoked from kernel context!", regs); local_irq_enable(); force_sig(SIGILL); local_irq_disable(); @@ -677,7 +679,6 @@ asmlinkage void noinstr do_reserved(struct pt_regs *reg= s) { irqentry_state_t state =3D irqentry_enter(regs); =20 - local_irq_enable(); /* * Game over - no way to handle this if it ever occurs. Most probably * caused by a fatal error after another hardware/software error. @@ -685,8 +686,8 @@ asmlinkage void noinstr do_reserved(struct pt_regs *reg= s) pr_err("Caught reserved exception %u on pid:%d [%s] - should not happen\n= ", read_csr_excode(), current->pid, current->comm); die_if_kernel("do_reserved exception", regs); + local_irq_enable(); force_sig(SIGUNUSED); - local_irq_disable(); =20 irqentry_exit(regs, state); --=20 2.34.3