| From | Greg Kroah-Hartman <> | Subject | [PATCH 3.15 13/84] i8k: Fix non-SMP operation | Date | Tue, 15 Jul 2014 16:17:10 -0700 |
| |
3.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Guenter Roeck <linux@roeck-us.net>
commit 6d827fbcc370ca259a2905309f64161ab7b10596 upstream.
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 <jim876@xs4all.nl> Tested-by: Jim Bos <jim876@xs4all.nl> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Cc: Andreas Mohr <andi@lisas.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- drivers/char/i8k.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- 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;
|