From 6d827fbcc370ca259a2905309f64161ab7b10596 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Sat, 21 Jun 2014 08:08:08 -0700 Subject: [PATCH] i8k: Fix non-SMP operation Commit f36fdb9f0266 (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: f36fdb9f0266 (i8k: Force SMM to run on CPU 0) Reported-by: Jim Bos Tested-by: Jim Bos Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Guenter Roeck Cc: Andreas Mohr Signed-off-by: Greg Kroah-Hartman --- drivers/char/i8k.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/char/i8k.c b/drivers/char/i8k.c index d915707d2ba1..93dcad0c1cbe 100644 --- a/drivers/char/i8k.c +++ b/drivers/char/i8k.c @@ -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, ¤t->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; -- 2.20.1