Commit 0f64b247 authored Aug 12, 2015 by Nicolas Pitre Committed by Russell King Aug 18, 2015

ARM: 8414/1: __copy_to_user_memcpy: fix mmap semaphore usage



The mmap semaphore should not be taken when page faults are disabled.
Since pagefault_disable() no longer disables preemption, we now need
to use faulthandler_disabled() in place of in_atomic().

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

parent 09edea4f

arch/arm/lib/uaccess_with_memcpy.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -96,7 +96,7 @@ __copy_to_user_memcpy(void __user to, const void from, unsigned long n)
		}

		/* the mmap semaphore is taken only if not in an atomic context */
		atomic = in_atomic();
		atomic = faulthandler_disabled();

		if (!atomic)
		down_read(&current->mm->mmap_sem);