Subject: mm: rt: Fix generic kmap_atomic for RT From: Thomas Gleixner Date: Sat, 19 Sep 2015 10:15:00 +0200 Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.11/older/patches-4.11.9-rt7.tar.xz The update to 4.1 brought in the mainline variant of the pagefault disable distangling from preempt count. That introduced a preempt_disable/enable pair in the generic kmap_atomic/kunmap_atomic implementations which got not converted to the _nort() variant. That results in massive 'scheduling while atomic/sleeping function called from invalid context' splats. Fix that up. Reported-and-tested-by: Juergen Borleis Signed-off-by: Thomas Gleixner --- include/linux/highmem.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -65,7 +65,7 @@ static inline void kunmap(struct page *p static inline void *kmap_atomic(struct page *page) { - preempt_disable(); + preempt_disable_nort(); pagefault_disable(); return page_address(page); } @@ -74,7 +74,7 @@ static inline void *kmap_atomic(struct p static inline void __kunmap_atomic(void *addr) { pagefault_enable(); - preempt_enable(); + preempt_enable_nort(); } #define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))