From 47cbf5771cd0a2ad4014e8d6e4881dc08d22971f Mon Sep 17 00:00:00 2001 From: Hui Wang Date: Thu, 9 Apr 2026 21:32:46 +0800 Subject: [PATCH 1/2] riscv: cpu_ops: Change return value type of cpu_is_stopped() to bool In the original sbi_cpu_is_stopped(), if rc doesn't equal to the SBI_HSM_STATE_STOPPED, it will return rc to the caller directly. But there is a hidden problem, the rc could be SBI_HSM_STATE_STARTED, if so, this function will report cpu stopped while the cpu isn't really stopped. Furthermore, from the name of cpu_is_stopped(), it gives a sense the return value is a bool type, true means the cpu is stopped, conversely false means the cpu is not stopped. Here change the return value type to bool and change the callers accordingly. This could fix the above two issues. Fixes: f1e58583b9c7c ("RISC-V: Support cpu hotplug") Signed-off-by: Hui Wang Signed-off-by: Linux RISC-V bot --- arch/riscv/include/asm/cpu_ops.h | 2 +- arch/riscv/kernel/cpu-hotplug.c | 2 +- arch/riscv/kernel/cpu_ops_sbi.c | 6 ++---- 3 files changed, 4 insertions(+), 6 deletions(-) diff --git a/arch/riscv/include/asm/cpu_ops.h b/arch/riscv/include/asm/cpu_ops.h index 176b570ef98276..065811fca594d9 100644 --- a/arch/riscv/include/asm/cpu_ops.h +++ b/arch/riscv/include/asm/cpu_ops.h @@ -24,7 +24,7 @@ struct cpu_operations { struct task_struct *tidle); #ifdef CONFIG_HOTPLUG_CPU void (*cpu_stop)(void); - int (*cpu_is_stopped)(unsigned int cpu); + bool (*cpu_is_stopped)(unsigned int cpu); #endif }; diff --git a/arch/riscv/kernel/cpu-hotplug.c b/arch/riscv/kernel/cpu-hotplug.c index 3f50d3dd76c6f2..9f8b714d12da28 100644 --- a/arch/riscv/kernel/cpu-hotplug.c +++ b/arch/riscv/kernel/cpu-hotplug.c @@ -58,7 +58,7 @@ void arch_cpuhp_cleanup_dead_cpu(unsigned int cpu) /* Verify from the firmware if the cpu is really stopped*/ if (cpu_ops->cpu_is_stopped) ret = cpu_ops->cpu_is_stopped(cpu); - if (ret) + if (!ret) pr_warn("CPU%u may not have stopped: %d\n", cpu, ret); } diff --git a/arch/riscv/kernel/cpu_ops_sbi.c b/arch/riscv/kernel/cpu_ops_sbi.c index 00aff669f5f2f5..a17b7576b77d23 100644 --- a/arch/riscv/kernel/cpu_ops_sbi.c +++ b/arch/riscv/kernel/cpu_ops_sbi.c @@ -88,16 +88,14 @@ static void sbi_cpu_stop(void) pr_crit("Unable to stop the cpu %d (%d)\n", smp_processor_id(), ret); } -static int sbi_cpu_is_stopped(unsigned int cpuid) +static bool sbi_cpu_is_stopped(unsigned int cpuid) { int rc; unsigned long hartid = cpuid_to_hartid_map(cpuid); rc = sbi_hsm_hart_get_status(hartid); - if (rc == SBI_HSM_STATE_STOPPED) - return 0; - return rc; + return (rc == SBI_HSM_STATE_STOPPED); } #endif From 639e8a6d973da2eb91734926971b06efd4ddb1bc Mon Sep 17 00:00:00 2001 From: Hui Wang Date: Thu, 9 Apr 2026 21:32:47 +0800 Subject: [PATCH 2/2] riscv: cpu_ops_sbi: No need to be bothered to check ret.error If the ret.error equals to 0, the sbi_err_map_linux_errno() can also handle it, i.e. if ret.error is SBI_SUCCESS, it will return 0 immediately, so no need to be bothered to check ret.error here. Signed-off-by: Hui Wang Signed-off-by: Linux RISC-V bot --- arch/riscv/kernel/cpu_ops_sbi.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/arch/riscv/kernel/cpu_ops_sbi.c b/arch/riscv/kernel/cpu_ops_sbi.c index a17b7576b77d23..07d5752a7b03ef 100644 --- a/arch/riscv/kernel/cpu_ops_sbi.c +++ b/arch/riscv/kernel/cpu_ops_sbi.c @@ -30,10 +30,8 @@ static int sbi_hsm_hart_start(unsigned long hartid, unsigned long saddr, ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_START, hartid, saddr, priv, 0, 0, 0); - if (ret.error) - return sbi_err_map_linux_errno(ret.error); - else - return 0; + + return sbi_err_map_linux_errno(ret.error); } #ifdef CONFIG_HOTPLUG_CPU @@ -43,10 +41,7 @@ static int sbi_hsm_hart_stop(void) ret = sbi_ecall(SBI_EXT_HSM, SBI_EXT_HSM_HART_STOP, 0, 0, 0, 0, 0, 0); - if (ret.error) - return sbi_err_map_linux_errno(ret.error); - else - return 0; + return sbi_err_map_linux_errno(ret.error); } static int sbi_hsm_hart_get_status(unsigned long hartid)