Merge branch 'fixes' of git://git.linaro.org/people/rmk/linux-arm

Pull ARM fixes from Russell King:
 "I've thought long and hard about what to say for this pull request,
  and I really can't work out anything sane to say to summarise much of
  these commits.  The problem is, for most of these are, yet again, lots
  of small bits scattered around the place without any real overall
  theme to them"

Most notable is probably the kuser page helper improvements.

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm: (22 commits)
  ARM: Add .text annotations where required after __CPUINIT removal
  ARM: 7803/1: Fix deadlock scenario with smp_send_stop()
  ARM: make vectors page inaccessible from userspace
  ARM: move signal handlers into a vdso-like page
  ARM: allow kuser helpers to be removed from the vector page
  ARM: update FIQ support for relocation of vectors
  ARM: use linker magic for vectors and vector stubs
  ARM: move vector stubs
  ARM: poison memory between kuser helpers
  ARM: poison the vectors page
  ARM: 7801/1: v6: prevent gcc 4.5 from reordering extended CP15 reads above is_smp() test
  ARM: 7800/1: ARMv7-M: Fix name of NVIC handler function
  ARM: Fix sorting of machine- initializers
  ARM: 7791/1: a.out: remove partial a.out support
  ARM: 7790/1: Fix deferred mm switch on VIVT processors
  ARM: 7789/1: Do not run dummy_flush_tlb_a15_erratum() on non-Cortex-A15
  ARM: 7787/1: virt: ensure visibility of __boot_cpu_mode
  ARM: 7788/1: elf: fix lpae hwcap feature reporting in proc/cpuinfo
  ARM: 7786/1: hyp: fix macro parameterisation
  ARM: 7785/1: mm: restrict early_alloc to section-aligned memory
  ...

1 files changed, 16 insertions, 4 deletions

diff --git a/arch/arm/include/asm/mmu_context.h b/arch/arm/include/asm/mmu_context.h
index b5792b7fd8d3..9b32f76bb0dd 100644
--- a/arch/arm/include/asm/mmu_context.h
+++ b/arch/arm/include/asm/mmu_context.h
@@ -56,7 +56,7 @@ static inline void check_and_switch_context(struct mm_struct *mm,
 		 * on non-ASID CPUs, the old mm will remain valid until the
 		 * finish_arch_post_lock_switch() call.
 		 */
-		set_ti_thread_flag(task_thread_info(tsk), TIF_SWITCH_MM);
+		mm->context.switch_pending = 1;
 	else
 		cpu_switch_mm(mm->pgd, mm);
 }
@@ -65,9 +65,21 @@ static inline void check_and_switch_context(struct mm_struct *mm,
 	finish_arch_post_lock_switch
 static inline void finish_arch_post_lock_switch(void)
 {
-	if (test_and_clear_thread_flag(TIF_SWITCH_MM)) {
-		struct mm_struct *mm = current->mm;
-		cpu_switch_mm(mm->pgd, mm);
+	struct mm_struct *mm = current->mm;
+
+	if (mm && mm->context.switch_pending) {
+		/*
+		 * Preemption must be disabled during cpu_switch_mm() as we
+		 * have some stateful cache flush implementations. Check
+		 * switch_pending again in case we were preempted and the
+		 * switch to this mm was already done.
+		 */
+		preempt_disable();
+		if (mm->context.switch_pending) {
+			mm->context.switch_pending = 0;
+			cpu_switch_mm(mm->pgd, mm);
+		}
+		preempt_enable_no_resched();
 	}
 }