The isolcpus kernel parameter restricts userspace from scheduling on the
specified cpus. If a cpu is specified that is outside the range of 0 to
nr_cpu_ids, cpulist_parse() will return -ERANGE, return an empty cpulist,
and fail silently.
This patch adds an error message to isolated_cpu_setup() to indicate to
the user that something has gone awry, and returns 0 on error.
Cc: Ingo Molnar <mi...@redhat.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Signed-off-by: Prarit Bhargava <pra...@redhat.com>
---
kernel/sched/core.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 9503d59..bce37ca 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6173,8 +6173,15 @@ cpu_attach_domain(struct sched_domain *sd, struct
root_domain *rd, int cpu)
/* Setup the mask of cpus configured for isolated domains */
static int __init isolated_cpu_setup(char *str)
{
+ int ret;
+
alloc_bootmem_cpumask_var(&cpu_isolated_map);
- cpulist_parse(str, cpu_isolated_map);
+ ret = cpulist_parse(str, cpu_isolated_map);
+ if (ret) {
+ pr_err("Error: kernel parameter isolcpus values must be between
0 and %d\n",
+ nr_cpu_ids);
+ return 0;
+ }
return 1;
}
--
1.7.9.3
