diff options
| author | Andrew Jones | 2022-10-14 17:58:44 +0200 |
|---|---|---|
| committer | Palmer Dabbelt | 2022-10-27 15:23:19 -0700 |
| commit | d14e99bf95510fa2d6affc371ad68161afc1dc8e (patch) | |
| tree | 5d96fff7ad69836db03f8cce8fcd09bc6e41250e /arch/riscv/kernel | |
| parent | 952b64d6665c8b6fdd13ba63be7adc3be51641d7 (diff) | |
RISC-V: Fix /proc/cpuinfo cpumask warning
Commit 78e5a3399421 ("cpumask: fix checking valid cpu range") has
started issuing warnings[*] when cpu indices equal to nr_cpu_ids - 1
are passed to cpumask_next* functions. seq_read_iter() and cpuinfo's
start and next seq operations implement a pattern like
n = cpumask_next(n - 1, mask);
show(n);
while (1) {
++n;
n = cpumask_next(n - 1, mask);
if (n >= nr_cpu_ids)
break;
show(n);
}
which will issue the warning when reading /proc/cpuinfo. Ensure no
warning is generated by validating the cpu index before calling
cpumask_next().
[*] Warnings will only appear with DEBUG_PER_CPU_MAPS enabled.
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Yury Norov <yury.norov@gmail.com>
Link: https://lore.kernel.org/r/20221014155845.1986223-2-ajones@ventanamicro.com/
Fixes: 78e5a3399421 ("cpumask: fix checking valid cpu range")
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/kernel')
| -rw-r--r-- | arch/riscv/kernel/cpu.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c index fa427bdcf773..852ecccd8920 100644 --- a/arch/riscv/kernel/cpu.c +++ b/arch/riscv/kernel/cpu.c @@ -213,6 +213,9 @@ static void print_mmu(struct seq_file *f) static void *c_start(struct seq_file *m, loff_t *pos) { + if (*pos == nr_cpu_ids) + return NULL; + *pos = cpumask_next(*pos - 1, cpu_online_mask); if ((*pos) < nr_cpu_ids) return (void *)(uintptr_t)(1 + *pos); |