Merge tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64

Pull arm64 fixes from Catalin Marinas:
 - Post -rc1 update to the common reboot infrastructure.
 - Fixes (user cache maintenance fault handling, !COMPAT compilation,
   CPU online and interrupt hanlding).

* tag 'arm64-stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64:
  arm64: use common reboot infrastructure
  arm64: mm: don't treat user cache maintenance faults as writes
  arm64: add '#ifdef CONFIG_COMPAT' for aarch32_break_handler()
  arm64: Only enable local interrupts after the CPU is marked online

Author: torvalds

arch/arm64/include/asm/debug-monitors.h

@@ -83,14 +83,7 @@ static inline int reinstall_suspended_bps(struct pt_regs *regs)
 }
 #endif
 
-#ifdef CONFIG_COMPAT
 int aarch32_break_handler(struct pt_regs *regs);
-#else
-static int aarch32_break_handler(struct pt_regs *regs)
-{
-	return -EFAULT;
-}
-#endif
 
 #endif	/* __ASSEMBLY */
 #endif	/* __KERNEL__ */

arch/arm64/include/asm/system_misc.h

@@ -23,6 +23,7 @@
 #include <linux/compiler.h>
 #include <linux/linkage.h>
 #include <linux/irqflags.h>
+#include <linux/reboot.h>
 
 struct pt_regs;
 
@@ -41,7 +42,7 @@ extern void show_pte(struct mm_struct *mm, unsigned long addr);
 extern void __show_regs(struct pt_regs *);
 
 void soft_restart(unsigned long);
-extern void (*arm_pm_restart)(char str, const char *cmd);
+extern void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd);
 
 #define UDBG_UNDEFINED	(1 << 0)
 #define UDBG_SYSCALL	(1 << 1)

arch/arm64/kernel/process.c

@@ -132,7 +132,7 @@ void machine_restart(char *cmd)
 
 	/* Now call the architecture specific reboot code. */
 	if (arm_pm_restart)
-		arm_pm_restart('h', cmd);
+		arm_pm_restart(reboot_mode, cmd);
 
 	/*
 	 * Whoops - the architecture was unable to reboot.

arch/arm64/kernel/smp.c

@@ -199,13 +199,6 @@ asmlinkage void secondary_start_kernel(void)
 	raw_spin_lock(&boot_lock);
 	raw_spin_unlock(&boot_lock);
 
-	/*
-	 * Enable local interrupts.
-	 */
-	notify_cpu_starting(cpu);
-	local_irq_enable();
-	local_fiq_enable();
-
 	/*
 	 * OK, now it's safe to let the boot CPU continue.  Wait for
 	 * the CPU migration code to notice that the CPU is online
@@ -214,6 +207,14 @@ asmlinkage void secondary_start_kernel(void)
 	set_cpu_online(cpu, true);
 	complete(&cpu_running);
 
+	/*
+	 * Enable GIC and timers.
+	 */
+	notify_cpu_starting(cpu);
+
+	local_irq_enable();
+	local_fiq_enable();
+
 	/*
 	 * OK, it's off to the idle thread for us
 	 */

arch/arm64/mm/fault.c

@@ -152,25 +152,8 @@ void do_bad_area(unsigned long addr, unsigned int esr, struct pt_regs *regs)
 #define ESR_CM			(1 << 8)
 #define ESR_LNX_EXEC		(1 << 24)
 
-/*
- * Check that the permissions on the VMA allow for the fault which occurred.
- * If we encountered a write fault, we must have write permission, otherwise
- * we allow any permission.
- */
-static inline bool access_error(unsigned int esr, struct vm_area_struct *vma)
-{
-	unsigned int mask = VM_READ | VM_WRITE | VM_EXEC;
-
-	if (esr & ESR_WRITE)
-		mask = VM_WRITE;
-	if (esr & ESR_LNX_EXEC)
-		mask = VM_EXEC;
-
-	return vma->vm_flags & mask ? false : true;
-}
-
 static int __do_page_fault(struct mm_struct *mm, unsigned long addr,
-			   unsigned int esr, unsigned int flags,
+			   unsigned int mm_flags, unsigned long vm_flags,
 			   struct task_struct *tsk)
 {
 	struct vm_area_struct *vma;
@@ -188,12 +171,17 @@ static int __do_page_fault(struct mm_struct *mm, unsigned long addr,
 	 * it.
 	 */
 good_area:
-	if (access_error(esr, vma)) {
+	/*
+	 * Check that the permissions on the VMA allow for the fault which
+	 * occurred. If we encountered a write or exec fault, we must have
+	 * appropriate permissions, otherwise we allow any permission.
+	 */
+	if (!(vma->vm_flags & vm_flags)) {
 		fault = VM_FAULT_BADACCESS;
 		goto out;
 	}
 
-	return handle_mm_fault(mm, vma, addr & PAGE_MASK, flags);
+	return handle_mm_fault(mm, vma, addr & PAGE_MASK, mm_flags);
 
 check_stack:
 	if (vma->vm_flags & VM_GROWSDOWN && !expand_stack(vma, addr))
@@ -208,9 +196,15 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 	struct task_struct *tsk;
 	struct mm_struct *mm;
 	int fault, sig, code;
-	bool write = (esr & ESR_WRITE) && !(esr & ESR_CM);
-	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE |
-		(write ? FAULT_FLAG_WRITE : 0);
+	unsigned long vm_flags = VM_READ | VM_WRITE | VM_EXEC;
+	unsigned int mm_flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
+
+	if (esr & ESR_LNX_EXEC) {
+		vm_flags = VM_EXEC;
+	} else if ((esr & ESR_WRITE) && !(esr & ESR_CM)) {
+		vm_flags = VM_WRITE;
+		mm_flags |= FAULT_FLAG_WRITE;
+	}
 
 	tsk = current;
 	mm  = tsk->mm;
@@ -248,7 +242,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 #endif
 	}
 
-	fault = __do_page_fault(mm, addr, esr, flags, tsk);
+	fault = __do_page_fault(mm, addr, mm_flags, vm_flags, tsk);
 
 	/*
 	 * If we need to retry but a fatal signal is pending, handle the
@@ -265,7 +259,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 	 */
 
 	perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr);
-	if (flags & FAULT_FLAG_ALLOW_RETRY) {
+	if (mm_flags & FAULT_FLAG_ALLOW_RETRY) {
 		if (fault & VM_FAULT_MAJOR) {
 			tsk->maj_flt++;
 			perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS_MAJ, 1, regs,
@@ -280,7 +274,7 @@ static int __kprobes do_page_fault(unsigned long addr, unsigned int esr,
 			 * Clear FAULT_FLAG_ALLOW_RETRY to avoid any risk of
 			 * starvation.
 			 */
-			flags &= ~FAULT_FLAG_ALLOW_RETRY;
+			mm_flags &= ~FAULT_FLAG_ALLOW_RETRY;
 			goto retry;
 		}
 	}