Commit 6d827fbc authored Jun 21, 2014 by Guenter Roeck Committed by Greg Kroah-Hartman Jul 09, 2014

i8k: Fix non-SMP operation



Commit f36fdb9f (i8k: Force SMM to run on CPU 0) adds support
for multi-core CPUs to the driver. Unfortunately, that causes it
to fail loading if compiled without SMP support, at least on
32 bit kernels. Kernel log shows "i8k: unable to get SMM Dell
signature", and function i8k_smm is found to return -EINVAL.

Testing revealed that the culprit is the missing return value check
of set_cpus_allowed_ptr.

Fixes: f36fdb9f (i8k: Force SMM to run on CPU 0)
Reported-by: Jim Bos <jim876@xs4all.nl>
Tested-by: Jim Bos <jim876@xs4all.nl>
Cc: stable@vger.kernel.org # 3.14+
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Andreas Mohr <andi@lisas.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 9bd2d0df

drivers/char/i8k.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -138,7 +138,9 @@ static int i8k_smm(struct smm_regs *regs)
		if (!alloc_cpumask_var(&old_mask, GFP_KERNEL))
		return -ENOMEM;
		cpumask_copy(old_mask, &current->cpus_allowed);
		set_cpus_allowed_ptr(current, cpumask_of(0));
		rc = set_cpus_allowed_ptr(current, cpumask_of(0));
		if (rc)
		goto out;
		if (smp_processor_id() != 0) {
		rc = -EBUSY;
		goto out;

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