Merge branch 'linus' into smp/hotplug

Apply upstream changes to avoid conflicts with pending patches.

1 files changed, 7 insertions, 0 deletions

diff --git a/arch/x86/include/asm/tlbflush.h b/arch/x86/include/asm/tlbflush.h
index 4e5be94e079a..6fa85944af83 100644
--- a/arch/x86/include/asm/tlbflush.h
+++ b/arch/x86/include/asm/tlbflush.h
@@ -135,7 +135,14 @@ static inline void cr4_set_bits_and_update_boot(unsigned long mask)
 
 static inline void __native_flush_tlb(void)
 {
+        /*
+         * If current->mm == NULL then we borrow a mm which may change during a
+         * task switch and therefore we must not be preempted while we write CR3
+         * back:
+         */
+        preempt_disable();
         native_write_cr3(native_read_cr3());
+        preempt_enable();
 }
 
 static inline void __native_flush_tlb_global_irq_disabled(void)