From: Sumit Garg <sumit.garg@linaro.org>
To: maz@kernel.org, catalin.marinas@arm.com, will@kernel.org,
daniel.thompson@linaro.org
Cc: linux-arm-kernel@lists.infradead.org, tglx@linutronix.de,
jason@lakedaemon.net, linux@armlinux.org.uk,
tsbogend@alpha.franken.de, mpe@ellerman.id.au,
davem@davemloft.net, mingo@redhat.com, bp@alien8.de,
x86@kernel.org, mark.rutland@arm.com,
julien.thierry.kdev@gmail.com, dianders@chromium.org,
jason.wessel@windriver.com, msys.mizuma@gmail.com,
ito-yuichi@fujitsu.com, kgdb-bugreport@lists.sourceforge.net,
linux-kernel@vger.kernel.org, Sumit Garg <sumit.garg@linaro.org>
Subject: [PATCH v7 5/7] arm64: ipi_nmi: Add support for NMI backtrace
Date: Mon, 2 Nov 2020 17:14:45 +0530 [thread overview]
Message-ID: <1604317487-14543-6-git-send-email-sumit.garg@linaro.org> (raw)
In-Reply-To: <1604317487-14543-1-git-send-email-sumit.garg@linaro.org>
Enable NMI backtrace support on arm64 using IPI turned as an NMI
leveraging pseudo NMIs support. It is now possible for users to get a
backtrace of a CPU stuck in hard-lockup using magic SYSRQ.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
---
arch/arm64/include/asm/irq.h | 6 ++++++
arch/arm64/kernel/ipi_nmi.c | 18 ++++++++++++++++--
2 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/include/asm/irq.h b/arch/arm64/include/asm/irq.h
index b2b0c64..ef018a8 100644
--- a/arch/arm64/include/asm/irq.h
+++ b/arch/arm64/include/asm/irq.h
@@ -6,6 +6,12 @@
#include <asm-generic/irq.h>
+#ifdef CONFIG_SMP
+extern bool arch_trigger_cpumask_backtrace(const cpumask_t *mask,
+ bool exclude_self);
+#define arch_trigger_cpumask_backtrace arch_trigger_cpumask_backtrace
+#endif
+
struct pt_regs;
static inline int nr_legacy_irqs(void)
diff --git a/arch/arm64/kernel/ipi_nmi.c b/arch/arm64/kernel/ipi_nmi.c
index a945dcf..597dcf7 100644
--- a/arch/arm64/kernel/ipi_nmi.c
+++ b/arch/arm64/kernel/ipi_nmi.c
@@ -8,6 +8,7 @@
#include <linux/interrupt.h>
#include <linux/irq.h>
+#include <linux/nmi.h>
#include <linux/smp.h>
#include <asm/nmi.h>
@@ -31,11 +32,24 @@ void arm64_send_nmi(cpumask_t *mask)
__ipi_send_mask(ipi_nmi_desc, mask);
}
+bool arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self)
+{
+ if (!ipi_nmi_desc)
+ return false;
+
+ nmi_trigger_cpumask_backtrace(mask, exclude_self, arm64_send_nmi);
+
+ return true;
+}
+
static irqreturn_t ipi_nmi_handler(int irq, void *data)
{
- /* nop, NMI handlers for special features can be added here. */
+ irqreturn_t ret = IRQ_NONE;
+
+ if (nmi_cpu_backtrace(get_irq_regs()))
+ ret = IRQ_HANDLED;
- return IRQ_NONE;
+ return ret;
}
void dynamic_ipi_setup(int cpu)
--
2.7.4
next prev parent reply other threads:[~2020-11-02 11:47 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-02 11:44 [PATCH v7 0/7] arm64: Add framework to turn an IPI as NMI Sumit Garg
2020-11-02 11:44 ` [PATCH v7 1/7] arm64: Add framework to turn " Sumit Garg
2020-11-02 15:33 ` Masayoshi Mizuma
2020-11-04 12:48 ` Sumit Garg
2020-11-02 11:44 ` [PATCH v7 2/7] irqchip/gic-v3: Enable support for SGIs to act as NMIs Sumit Garg
2020-11-02 16:17 ` Masayoshi Mizuma
2020-11-18 11:54 ` ito-yuichi
2020-11-02 11:44 ` [PATCH v7 3/7] arm64: smp: Assign and setup an IPI as NMI Sumit Garg
2020-11-02 16:19 ` Masayoshi Mizuma
2020-11-02 11:44 ` [PATCH v7 4/7] nmi: backtrace: Allow runtime arch specific override Sumit Garg
2021-01-05 10:32 ` Sumit Garg
2020-11-02 11:44 ` Sumit Garg [this message]
2020-11-02 16:21 ` [PATCH v7 5/7] arm64: ipi_nmi: Add support for NMI backtrace Masayoshi Mizuma
2020-11-02 11:44 ` [PATCH v7 6/7] kgdb: Expose default CPUs roundup fallback mechanism Sumit Garg
2020-11-02 11:44 ` [PATCH v7 7/7] arm64: kgdb: Roundup cpus using IPI as NMI Sumit Garg
2021-06-25 14:54 ` Chen-Yu Tsai
2021-01-05 10:34 ` [PATCH v7 0/7] arm64: Add framework to turn an " Sumit Garg
2021-01-05 10:43 ` Marc Zyngier
2021-07-07 6:03 ` Sumit Garg
2021-06-25 14:56 ` Chen-Yu Tsai
2021-07-07 5:59 ` Sumit Garg
2022-01-12 19:31 ` Masayoshi Mizuma
2022-01-13 11:00 ` Sumit Garg
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