linux-kernel - [PATCH v2 7/8] riscv: smp: kgdb: Use NMI for CPU roundup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20251118025015.42491-8-cuiyunhui@bytedance.com>
Date: Tue, 18 Nov 2025 10:50:14 +0800
From: Yunhui Cui <cuiyunhui@...edance.com>
To: conor@...nel.org,
	paul.walmsley@...ive.com,
	palmer@...belt.com,
	aou@...s.berkeley.edu,
	alex@...ti.fr,
	cuiyunhui@...edance.com,
	luxu.kernel@...edance.com,
	linux-kernel@...r.kernel.org,
	linux-riscv@...ts.infradead.org,
	jassisinghbrar@...il.com,
	conor.dooley@...rochip.com,
	valentina.fernandezalanis@...rochip.com,
	catalin.marinas@....com,
	will@...nel.org,
	maz@...nel.org,
	timothy.hayes@....com,
	lpieralisi@...nel.org,
	arnd@...db.de,
	kees@...nel.org,
	tglx@...utronix.de,
	viresh.kumar@...aro.org,
	boqun.feng@...il.com,
	linux-arm-kernel@...ts.infradead.org,
	cleger@...osinc.com,
	atishp@...osinc.com,
	ajones@...tanamicro.com
Subject: [PATCH v2 7/8] riscv: smp: kgdb: Use NMI for CPU roundup

Use NMI for kgdb CPU roundup if RISC-V SSE NMI is available.

Signed-off-by: Yunhui Cui <cuiyunhui@...edance.com>
---
 arch/riscv/kernel/smp.c                | 5 ++++-
 drivers/firmware/riscv/riscv_sse_nmi.c | 2 ++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 26083fe0a5df6..b1cefb2b0b8c2 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -382,7 +382,10 @@ void kgdb_roundup_cpus(void)
 		if (cpu == this_cpu)
 			continue;
 
-		send_ipi_single(cpu, IPI_KGDB_ROUNDUP);
+		if (!nmi_support())
+			send_ipi_single(cpu, IPI_KGDB_ROUNDUP);
+		else
+			send_nmi_single(cpu, LOCAL_NMI_KGDB);
 	}
 }
 #endif
diff --git a/drivers/firmware/riscv/riscv_sse_nmi.c b/drivers/firmware/riscv/riscv_sse_nmi.c
index cac940b7e8773..5035d4ec485f6 100644
--- a/drivers/firmware/riscv/riscv_sse_nmi.c
+++ b/drivers/firmware/riscv/riscv_sse_nmi.c
@@ -3,6 +3,7 @@
 #define pr_fmt(fmt) "SSE NMI: " fmt
 
 #include <linux/atomic.h>
+#include <linux/kgdb.h>
 #include <linux/nmi.h>
 #include <linux/riscv_sbi_sse.h>
 #include <linux/riscv_sse_nmi.h>
@@ -58,6 +59,7 @@ static int local_nmi_handler(u32 evt, void *arg, struct pt_regs *regs)
 	NMI_HANDLE(LOCAL_NMI_CRASH, cpu_crash_stop, cpu, regs);
 	NMI_HANDLE(LOCAL_NMI_STOP, cpu_stop);
 	NMI_HANDLE(LOCAL_NMI_BACKTRACE, nmi_cpu_backtrace, regs);
+	NMI_HANDLE(LOCAL_NMI_KGDB, kgdb_nmicallback, cpu, regs);
 
 	atomic_set(&local_nmi_arg, LOCAL_NMI_NONE);
 
-- 
2.39.5