Commit a6e4491c authored Feb 04, 2016 by Prarit Bhargava Committed by Ingo Molnar Feb 05, 2016

sched/isolcpus: Output warning when the 'isolcpus=' kernel parameter is invalid



The isolcpus= kernel boot 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.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1454596680-10367-1-git-send-email-prarit@redhat.com


[ Twiddled some details. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent b37a05c0

kernel/sched/core.c

+7 −2

Original line number	Diff line number	Diff line
		@@ -6173,11 +6173,16 @@ 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("sched: Error, all isolcpus= values must be between 0 and %d\n", nr_cpu_ids);
		return 0;
		}
		return 1;
		}

		__setup("isolcpus=", isolated_cpu_setup);

		struct s_data {

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