diff mbox series

sched/isolation: Warn about missing isolcpus mask

Message ID 20240110114610.1941474-1-vschneid@redhat.com
State New
Headers
Series sched/isolation: Warn about missing isolcpus mask |

Commit Message

Valentin Schneider Jan. 10, 2024, 11:46 a.m. UTC 
  Since an empty string is a valid cpulist, this cmdline option does not
trigger any warnings:

  isolcpus=domain,

housekeeping_setup() just carries on and we end up with the housekeeping
mask being all CPUs in the system.

Check that there *is* a cpulist and that it isn't empty.

Signed-off-by: Valentin Schneider <vschneid@redhat.com>
---
 kernel/sched/isolation.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Frederic Weisbecker Jan. 10, 2024, 2:12 p.m. UTC | #1 
Le Wed, Jan 10, 2024 at 12:46:10PM +0100, Valentin Schneider a écrit :
> Since an empty string is a valid cpulist, this cmdline option does not
> trigger any warnings:
> 
>   isolcpus=domain,
> 
> housekeeping_setup() just carries on and we end up with the housekeeping
> mask being all CPUs in the system.
> 
> Check that there *is* a cpulist and that it isn't empty.
> 
> Signed-off-by: Valentin Schneider <vschneid@redhat.com>

Acked-by: Frederic Weisbecker <frederic@kernel.org>
diff mbox series

Patch

diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
index 373d42c707bc5..aa20cd1702199 100644
--- a/kernel/sched/isolation.c
+++ b/kernel/sched/isolation.c
@@ -120,7 +120,8 @@  static int __init housekeeping_setup(char *str, unsigned long flags)
 	}
 
 	alloc_bootmem_cpumask_var(&non_housekeeping_mask);
-	if (cpulist_parse(str, non_housekeeping_mask) < 0) {
+	if (cpulist_parse(str, non_housekeeping_mask) < 0 ||
+	    cpumask_empty(non_housekeeping_mask)) {
 		pr_warn("Housekeeping: nohz_full= or isolcpus= incorrect CPU range\n");
 		goto free_non_housekeeping_mask;
 	}