From nobody Fri Apr 10 20:16:09 2026 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 D87A9C00140 for ; Fri, 19 Aug 2022 02:55:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344827AbiHSCzG (ORCPT ); Thu, 18 Aug 2022 22:55:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33842 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344144AbiHSCzC (ORCPT ); Thu, 18 Aug 2022 22:55:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 464D3D4754; Thu, 18 Aug 2022 19:55:02 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C690061497; Fri, 19 Aug 2022 02:55:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D8BEC43470; Fri, 19 Aug 2022 02:54:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660877701; bh=zq25NiQZz8wm9vgW2vXpq0gI46axFgfL/4UUq2ViQfE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=a1wYDWHTZYUUxwYK/nj4O4YiPzJK1smkXVk3AeWY1NMnE69c+JJgpQc4q+VZnvVXB ZU2mPgiJie2AF9xGl9y8ujXfXJfN/GLRYvKusO7va6avKM+enAuxZsuES5oLyMKMPc b5y2ieqt+nrUoIw1Of58iJNwrCR//0ShziKdsrh66bm2TpoZuopmULalJVgdW5xPBy lRTqotAZTLAQ2tgMm1g/qjvonFJslubOOU3z2w68OizLn1Mq7aAl3cwfwYt+hqh9pt J2zE2TlQ67eX3dCYdP83LRsZ1yzECuFYONMTlY5ch5JnzuOSfxijxkyoxJtaXLgu9/ szCHY15Cs+b8w== From: guoren@kernel.org To: xianting.tian@linux.alibaba.com, palmer@dabbelt.com, heiko@sntech.de, guoren@kernel.org, conor.dooley@microchip.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, liaochang1@huawei.com, mick@ics.forth.gr, jszhang@kernel.org, Guo Ren , Will Deacon , AKASHI Takahiro Subject: [PATCH V3 1/3] riscv: kexec: Disable all interrupts in kexec crash path Date: Thu, 18 Aug 2022 22:54:42 -0400 Message-Id: <20220819025444.2121315-2-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220819025444.2121315-1-guoren@kernel.org> References: <20220819025444.2121315-1-guoren@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Guo Ren If a crash happens on cpu3 and all interrupts are binding on cpu0, the bad irq routing will cause a crash kernel which can't receive any irq. Because crash kernel won't clean up all harts' PLIC enable bits in enable registers. This patch is similar to 9141a003a491 ("ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path") and 78fd584cdec0 ("arm64: kdump: implement machine_crash_shutdown()"), and PowerPC also has the same mechanism. Fixes: fba8a8674f68 ("RISC-V: Add kexec support") Reviewed-by: Xianting Tian Signed-off-by: Guo Ren Signed-off-by: Guo Ren Cc: Will Deacon Cc: AKASHI Takahiro Cc: Nick Kossifidis --- arch/riscv/kernel/machine_kexec.c | 35 +++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/arch/riscv/kernel/machine_kexec.c b/arch/riscv/kernel/machine_= kexec.c index ee79e6839b86..db41c676e5a2 100644 --- a/arch/riscv/kernel/machine_kexec.c +++ b/arch/riscv/kernel/machine_kexec.c @@ -15,6 +15,8 @@ #include /* For unreachable() */ #include /* For cpu_down() */ #include +#include +#include =20 /* * kexec_image_info - Print received image details @@ -154,6 +156,37 @@ void crash_smp_send_stop(void) cpus_stopped =3D 1; } =20 +static void machine_kexec_mask_interrupts(void) +{ + unsigned int i; + struct irq_desc *desc; + + for_each_irq_desc(i, desc) { + struct irq_chip *chip; + int ret; + + chip =3D irq_desc_get_chip(desc); + if (!chip) + continue; + + /* + * First try to remove the active state. If this + * fails, try to EOI the interrupt. + */ + ret =3D irq_set_irqchip_state(i, IRQCHIP_STATE_ACTIVE, false); + + if (ret && irqd_irq_inprogress(&desc->irq_data) && + chip->irq_eoi) + chip->irq_eoi(&desc->irq_data); + + if (chip->irq_mask) + chip->irq_mask(&desc->irq_data); + + if (chip->irq_disable && !irqd_irq_disabled(&desc->irq_data)) + chip->irq_disable(&desc->irq_data); + } +} + /* * machine_crash_shutdown - Prepare to kexec after a kernel crash * @@ -169,6 +202,8 @@ machine_crash_shutdown(struct pt_regs *regs) crash_smp_send_stop(); =20 crash_save_cpu(regs, smp_processor_id()); + machine_kexec_mask_interrupts(); + pr_info("Starting crashdump kernel...\n"); } =20 --=20 2.36.1 From nobody Fri Apr 10 20:16:09 2026 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 870E3C00140 for ; Fri, 19 Aug 2022 02:55:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345037AbiHSCzP (ORCPT ); Thu, 18 Aug 2022 22:55:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240055AbiHSCzI (ORCPT ); Thu, 18 Aug 2022 22:55:08 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 93C03D475E; Thu, 18 Aug 2022 19:55:07 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BE51B6149F; Fri, 19 Aug 2022 02:55:06 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DC63DC433D6; Fri, 19 Aug 2022 02:55:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660877706; bh=L+xboeNH8l7ZwFQaftSBPGndlJHEKNh0TrL7kdxKPdc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sjIRIwuAg6ILkyUIM1xcwuxjoUmPwxbBsg9R08TwsQNa6G08P4nBCNSzQfVgMGDCp Ymm4rgtL4lzJpHpbk0xyapoI0At2W231ExlPmwNF+FThztOl+NKPP6E/ZyhyUGG+DE c/zWmbdqHGpMe1n/DE5rqf8I8/LTf6dAK+ucQZgkJ+E9EyHolpfxzyjSKPZ1NDNHI0 kmKQVrX4+xMbtcbnf6bduxOxdSm+33SqIlULsgWRuQ9/N4omS9kNrLfEkPYSersMJ/ p2QSvcIGq+CStk40W9jh7GuYwii1HxoUeLe16FUWSBU/heVhicSSO61tXjuYa4e2Jy GZUlGTE6tn+2w== From: guoren@kernel.org To: xianting.tian@linux.alibaba.com, palmer@dabbelt.com, heiko@sntech.de, guoren@kernel.org, conor.dooley@microchip.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, liaochang1@huawei.com, mick@ics.forth.gr, jszhang@kernel.org, Guo Ren , AKASHI Takahiro Subject: [PATCH V3 2/3] riscv: kexec: Fixup crash_smp_send_stop with percpu crash_save_cpu Date: Thu, 18 Aug 2022 22:54:43 -0400 Message-Id: <20220819025444.2121315-3-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220819025444.2121315-1-guoren@kernel.org> References: <20220819025444.2121315-1-guoren@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Guo Ren Current crash_smp_send_stop is the same as the generic one in kernel/panic and misses crash_save_cpu in percpu. This patch is inspired by 78fd584cdec0 ("arm64: kdump: implement machine_crash_shutdown()") and adds the same mechanism for riscv. Fixes: ad943893d5f1 ("RISC-V: Fixup schedule out issue in machine_crash_shu= tdown()") Reviewed-by: Xianting Tian Signed-off-by: Guo Ren Signed-off-by: Guo Ren Cc: AKASHI Takahiro --- arch/riscv/include/asm/smp.h | 3 ++ arch/riscv/kernel/machine_kexec.c | 21 ++------ arch/riscv/kernel/smp.c | 89 ++++++++++++++++++++++++++++++- 3 files changed, 95 insertions(+), 18 deletions(-) diff --git a/arch/riscv/include/asm/smp.h b/arch/riscv/include/asm/smp.h index d3443be7eedc..3831b638ecab 100644 --- a/arch/riscv/include/asm/smp.h +++ b/arch/riscv/include/asm/smp.h @@ -50,6 +50,9 @@ void riscv_set_ipi_ops(const struct riscv_ipi_ops *ops); /* Clear IPI for current CPU */ void riscv_clear_ipi(void); =20 +/* Check other CPUs stop or not */ +bool smp_crash_stop_failed(void); + /* Secondary hart entry */ asmlinkage void smp_callin(void); =20 diff --git a/arch/riscv/kernel/machine_kexec.c b/arch/riscv/kernel/machine_= kexec.c index db41c676e5a2..2d139b724bc8 100644 --- a/arch/riscv/kernel/machine_kexec.c +++ b/arch/riscv/kernel/machine_kexec.c @@ -140,22 +140,6 @@ void machine_shutdown(void) #endif } =20 -/* Override the weak function in kernel/panic.c */ -void crash_smp_send_stop(void) -{ - static int cpus_stopped; - - /* - * This function can be called twice in panic path, but obviously - * we execute this only once. - */ - if (cpus_stopped) - return; - - smp_send_stop(); - cpus_stopped =3D 1; -} - static void machine_kexec_mask_interrupts(void) { unsigned int i; @@ -230,6 +214,11 @@ machine_kexec(struct kimage *image) void *control_code_buffer =3D page_address(image->control_code_page); riscv_kexec_method kexec_method =3D NULL; =20 +#ifdef CONFIG_SMP + WARN(smp_crash_stop_failed(), + "Some CPUs may be stale, kdump will be unreliable.\n"); +#endif + if (image->type !=3D KEXEC_TYPE_CRASH) kexec_method =3D control_code_buffer; else diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c index 760a64518c58..a75ad9c373cd 100644 --- a/arch/riscv/kernel/smp.c +++ b/arch/riscv/kernel/smp.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -27,6 +28,7 @@ enum ipi_message_type { IPI_RESCHEDULE, IPI_CALL_FUNC, IPI_CPU_STOP, + IPI_CPU_CRASH_STOP, IPI_IRQ_WORK, IPI_TIMER, IPI_MAX @@ -71,6 +73,22 @@ static void ipi_stop(void) wait_for_interrupt(); } =20 +#ifdef CONFIG_KEXEC_CORE +static atomic_t waiting_for_crash_ipi =3D ATOMIC_INIT(0); + +static void ipi_cpu_crash_stop(unsigned int cpu, struct pt_regs *regs) +{ + crash_save_cpu(regs, cpu); + + atomic_dec(&waiting_for_crash_ipi); + + local_irq_disable(); + + while(1) + wait_for_interrupt(); +} +#endif + static const struct riscv_ipi_ops *ipi_ops __ro_after_init; =20 void riscv_set_ipi_ops(const struct riscv_ipi_ops *ops) @@ -124,8 +142,9 @@ void arch_irq_work_raise(void) =20 void handle_IPI(struct pt_regs *regs) { - unsigned long *pending_ipis =3D &ipi_data[smp_processor_id()].bits; - unsigned long *stats =3D ipi_data[smp_processor_id()].stats; + unsigned int cpu =3D smp_processor_id(); + unsigned long *pending_ipis =3D &ipi_data[cpu].bits; + unsigned long *stats =3D ipi_data[cpu].stats; =20 riscv_clear_ipi(); =20 @@ -154,6 +173,13 @@ void handle_IPI(struct pt_regs *regs) ipi_stop(); } =20 + if (ops & (1 << IPI_CPU_CRASH_STOP)) { +#ifdef CONFIG_KEXEC_CORE + ipi_cpu_crash_stop(cpu, get_irq_regs()); +#endif + unreachable(); + } + if (ops & (1 << IPI_IRQ_WORK)) { stats[IPI_IRQ_WORK]++; irq_work_run(); @@ -176,6 +202,7 @@ static const char * const ipi_names[] =3D { [IPI_RESCHEDULE] =3D "Rescheduling interrupts", [IPI_CALL_FUNC] =3D "Function call interrupts", [IPI_CPU_STOP] =3D "CPU stop interrupts", + [IPI_CPU_CRASH_STOP] =3D "CPU stop (for crash dump) interrupts", [IPI_IRQ_WORK] =3D "IRQ work interrupts", [IPI_TIMER] =3D "Timer broadcast interrupts", }; @@ -235,6 +262,64 @@ void smp_send_stop(void) cpumask_pr_args(cpu_online_mask)); } =20 +#ifdef CONFIG_KEXEC_CORE +/* + * The number of CPUs online, not counting this CPU (which may not be + * fully online and so not counted in num_online_cpus()). + */ +static inline unsigned int num_other_online_cpus(void) +{ + unsigned int this_cpu_online =3D cpu_online(smp_processor_id()); + + return num_online_cpus() - this_cpu_online; +} + +void crash_smp_send_stop(void) +{ + static int cpus_stopped; + cpumask_t mask; + unsigned long timeout; + + /* + * This function can be called twice in panic path, but obviously + * we execute this only once. + */ + if (cpus_stopped) + return; + + cpus_stopped =3D 1; + + /* + * If this cpu is the only one alive at this point in time, online or + * not, there are no stop messages to be sent around, so just back out. + */ + if (num_other_online_cpus() =3D=3D 0) + return; + + cpumask_copy(&mask, cpu_online_mask); + cpumask_clear_cpu(smp_processor_id(), &mask); + + atomic_set(&waiting_for_crash_ipi, num_other_online_cpus()); + + pr_crit("SMP: stopping secondary CPUs\n"); + send_ipi_mask(&mask, IPI_CPU_CRASH_STOP); + + /* Wait up to one second for other CPUs to stop */ + timeout =3D USEC_PER_SEC; + while ((atomic_read(&waiting_for_crash_ipi) > 0) && timeout--) + udelay(1); + + if (atomic_read(&waiting_for_crash_ipi) > 0) + pr_warn("SMP: failed to stop secondary CPUs %*pbl\n", + cpumask_pr_args(&mask)); +} + +bool smp_crash_stop_failed(void) +{ + return (atomic_read(&waiting_for_crash_ipi) > 0); +} +#endif + void smp_send_reschedule(int cpu) { send_ipi_single(cpu, IPI_RESCHEDULE); --=20 2.36.1 From nobody Fri Apr 10 20:16:09 2026 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 3FE7CC00140 for ; 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d=kernel.org; s=k20201202; t=1660877712; bh=+m/z9t7difm+T7Kf5VxuNeNPtaHK+1MlGIRm7crGn/M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b/KIBp6hGb/CV7ctjyoNlVNQctbDKqvWvOycBri2jc8hs9jUBTknd3RUQZctSwBLL yxSkFw0wSgftsks4Jezn7Vkx/H3bXALoSoIeBckdBjW9MMbGpWsWOjeRdf7u3z5SIU i6JkQUV3k0hBw1x10fSsb1DSNVGOVd6XnafE0lln8m68gdOiySWihoy1hal61YTPhL JVx1X0kgAnAr3Q3mh1rJwygcyxhoEyqMe//CRj+Au8ixgPCs3/lUYs5fY4Aaj3qp6R Y2aOOyquD6emEJypZunLgSQEEWmPr8Rt85PLL1Hrtdg4QeqLhKpPq/SjH/8sWci13v zeg/00VCA9i0Q== From: guoren@kernel.org To: xianting.tian@linux.alibaba.com, palmer@dabbelt.com, heiko@sntech.de, guoren@kernel.org, conor.dooley@microchip.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, liaochang1@huawei.com, mick@ics.forth.gr, jszhang@kernel.org, Guo Ren , Arnd Bergmann , Will Deacon , Catalin Marinas , x86@kernel.org Subject: [PATCH V3 3/3] arch: crash: Remove duplicate declaration in smp.h Date: Thu, 18 Aug 2022 22:54:44 -0400 Message-Id: <20220819025444.2121315-4-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220819025444.2121315-1-guoren@kernel.org> References: <20220819025444.2121315-1-guoren@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Guo Ren Remove crash_smp_send_stop declarations in arm64, x86 asm/smp.h which has been done in include/linux/smp.h. Signed-off-by: Guo Ren Signed-off-by: Guo Ren Cc: Arnd Bergmann Cc: Will Deacon Cc: Catalin Marinas Cc: x86@kernel.org --- arch/arm64/include/asm/smp.h | 1 - arch/x86/include/asm/crash.h | 1 - 2 files changed, 2 deletions(-) diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index fc55f5a57a06..a108ac93fd8f 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -141,7 +141,6 @@ static inline void cpu_panic_kernel(void) */ bool cpus_are_stuck_in_kernel(void); =20 -extern void crash_smp_send_stop(void); extern bool smp_crash_stop_failed(void); extern void panic_smp_self_stop(void); =20 diff --git a/arch/x86/include/asm/crash.h b/arch/x86/include/asm/crash.h index 8b6bd63530dc..6a9be4907c82 100644 --- a/arch/x86/include/asm/crash.h +++ b/arch/x86/include/asm/crash.h @@ -7,6 +7,5 @@ struct kimage; int crash_load_segments(struct kimage *image); int crash_setup_memmap_entries(struct kimage *image, struct boot_params *params); -void crash_smp_send_stop(void); =20 #endif /* _ASM_X86_CRASH_H */ --=20 2.36.1