diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h
index 3128a9ca5701..a4aa22241dd1 100644
--- a/arch/arm64/include/asm/assembler.h
+++ b/arch/arm64/include/asm/assembler.h
@@ -32,6 +32,23 @@
#include <asm/ptrace.h>
#include <asm/thread_info.h>
+ .macro save_and_disable_daif, flags
+ mrs \flags, daif
+ msr daifset, #0xf
+ .endm
+
+ .macro disable_daif
+ msr daifset, #0xf
+ .endm
+
+ .macro enable_daif
+ msr daifclr, #0xf
+ .endm
+
+ .macro restore_daif, flags:req
+ msr daif, \flags
+ .endm
+
/*
* Enable and disable interrupts.
*/
diff --git a/arch/arm64/include/asm/daifflags.h b/arch/arm64/include/asm/daifflags.h
new file mode 100644
index 000000000000..55e2598a8c4c
--- /dev/null
+++ b/arch/arm64/include/asm/daifflags.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2017 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_DAIFFLAGS_H
+#define __ASM_DAIFFLAGS_H
+
+#include <linux/irqflags.h>
+
+/* mask/save/unmask/restore all exceptions, including interrupts. */
+static inline void local_daif_mask(void)
+{
+ asm volatile(
+ "msr daifset, #0xf // local_daif_mask\n"
+ :
+ :
+ : "memory");
+ trace_hardirqs_off();
+}
+
+static inline unsigned long local_daif_save(void)
+{
+ unsigned long flags;
+
+ asm volatile(
+ "mrs %0, daif // local_daif_save\n"
+ : "=r" (flags)
+ :
+ : "memory");
+ local_daif_mask();
+
+ return flags;
+}
+
+static inline void local_daif_unmask(void)
+{
+ trace_hardirqs_on();
+ asm volatile(
+ "msr daifclr, #0xf // local_daif_unmask"
+ :
+ :
+ : "memory");
+}
+
+static inline void local_daif_restore(unsigned long flags)
+{
+ if (!arch_irqs_disabled_flags(flags))
+ trace_hardirqs_on();
+ asm volatile(
+ "msr daif, %0 // local_daif_restore"
+ :
+ : "r" (flags)
+ : "memory");
+ if (arch_irqs_disabled_flags(flags))
+ trace_hardirqs_off();
+}
+
+#endif
diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c
index 095d3c170f5d..3009b8b80f08 100644
--- a/arch/arm64/kernel/hibernate.c
+++ b/arch/arm64/kernel/hibernate.c
@@ -27,6 +27,7 @@
#include <asm/barrier.h>
#include <asm/cacheflush.h>
#include <asm/cputype.h>
+#include <asm/daifflags.h>
#include <asm/irqflags.h>
#include <asm/kexec.h>
#include <asm/memory.h>
@@ -285,7 +286,7 @@ int swsusp_arch_suspend(void)
return -EBUSY;
}
- local_dbg_save(flags);
+ flags = local_daif_save();
if (__cpu_suspend_enter(&state)) {
/* make the crash dump kernel image visible/saveable */
@@ -315,7 +316,7 @@ int swsusp_arch_suspend(void)
__cpu_suspend_exit();
}
- local_dbg_restore(flags);
+ local_daif_restore(flags);
return ret;
}
diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c
index 11121f608eb5..f76ea92dff91 100644
--- a/arch/arm64/kernel/machine_kexec.c
+++ b/arch/arm64/kernel/machine_kexec.c
@@ -18,6 +18,7 @@
#include <asm/cacheflush.h>
#include <asm/cpu_ops.h>
+#include <asm/daifflags.h>
#include <asm/memory.h>
#include <asm/mmu.h>
#include <asm/mmu_context.h>
@@ -195,8 +196,7 @@ void machine_kexec(struct kimage *kimage)
pr_info("Bye!\n");
- /* Disable all DAIF exceptions. */
- asm volatile ("msr daifset, #0xf" : : : "memory");
+ local_daif_mask();
/*
* cpu_soft_restart will shutdown the MMU, disable data caches, then
diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 824561ef6b8a..c94f4a6515c4 100644
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -47,6 +47,7 @@
#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/cpu_ops.h>
+#include <asm/daifflags.h>
#include <asm/mmu_context.h>
#include <asm/numa.h>
#include <asm/pgtable.h>
@@ -370,10 +371,6 @@ void __cpu_die(unsigned int cpu)
/*
* Called from the idle thread for the CPU which has been shutdown.
*
- * Note that we disable IRQs here, but do not re-enable them
- * before returning to the caller. This is also the behaviour
- * of the other hotplug-cpu capable cores, so presumably coming
- * out of idle fixes this.
*/
void cpu_die(void)
{
@@ -381,7 +378,7 @@ void cpu_die(void)
idle_task_exit();
- local_irq_disable();
+ local_daif_mask();
/* Tell __cpu_die() that this CPU is now safe to dispose of */
(void)cpu_report_death();
@@ -839,7 +836,7 @@ static void ipi_cpu_stop(unsigned int cpu)
{
set_cpu_online(cpu, false);
- local_irq_disable();
+ local_daif_mask();
while (1)
cpu_relax();
diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c
index 5794326975f8..9079dfe885fa 100644
--- a/arch/arm64/kernel/suspend.c
+++ b/arch/arm64/kernel/suspend.c
@@ -4,6 +4,7 @@
#include <asm/alternative.h>
#include <asm/cacheflush.h>
#include <asm/cpufeature.h>
+#include <asm/daifflags.h>
#include <asm/debug-monitors.h>
#include <asm/exec.h>
#include <asm/pgtable.h>
@@ -56,7 +57,7 @@ void notrace __cpu_suspend_exit(void)
/*
* Restore HW breakpoint registers to sane values
* before debug exceptions are possibly reenabled
- * through local_dbg_restore.
+ * by cpu_suspend()s local_daif_restore() call.
*/
if (hw_breakpoint_restore)
hw_breakpoint_restore(cpu);
@@ -80,7 +81,7 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
* updates to mdscr register (saved and restored along with
* general purpose registers) from kernel debuggers.
*/
- local_dbg_save(flags);
+ flags = local_daif_save();
/*
* Function graph tracer state gets incosistent when the kernel
@@ -113,7 +114,7 @@ int cpu_suspend(unsigned long arg, int (*fn)(unsigned long))
* restored, so from this point onwards, debugging is fully
* renabled if it was enabled when core started shutdown.
*/
- local_dbg_restore(flags);
+ local_daif_restore(flags);
return ret;
}
diff --git a/arch/arm64/kernel/traps.c b/arch/arm64/kernel/traps.c
index afb6b19677dc..fa52aefaf7f2 100644
--- a/arch/arm64/kernel/traps.c
+++ b/arch/arm64/kernel/traps.c
@@ -38,6 +38,7 @@
#include <asm/atomic.h>
#include <asm/bug.h>
+#include <asm/daifflags.h>
#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/insn.h>
@@ -594,7 +595,7 @@ asmlinkage void bad_mode(struct pt_regs *regs, int reason, unsigned int esr)
esr_get_class_string(esr));
die("Oops - bad mode", regs, 0);
- local_irq_disable();
+ local_daif_mask();
panic("bad mode");
}
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S
index 877d42fb0df6..95233dfc4c39 100644
--- a/arch/arm64/mm/proc.S
+++ b/arch/arm64/mm/proc.S
@@ -109,10 +109,10 @@ ENTRY(cpu_do_resume)
/*
* __cpu_setup() cleared MDSCR_EL1.MDE and friends, before unmasking
* debug exceptions. By restoring MDSCR_EL1 here, we may take a debug
- * exception. Mask them until local_dbg_restore() in cpu_suspend()
+ * exception. Mask them until local_daif_restore() in cpu_suspend()
* resets them.
*/
- disable_dbg
+ disable_daif
msr mdscr_el1, x10
msr sctlr_el1, x12
@@ -155,8 +155,7 @@ ENDPROC(cpu_do_switch_mm)
* called by anything else. It can only be executed from a TTBR0 mapping.
*/
ENTRY(idmap_cpu_replace_ttbr1)
- mrs x2, daif
- msr daifset, #0xf
+ save_and_disable_daif flags=x2
adrp x1, empty_zero_page
msr ttbr1_el1, x1
@@ -169,7 +168,7 @@ ENTRY(idmap_cpu_replace_ttbr1)
msr ttbr1_el1, x0
isb
- msr daif, x2
+ restore_daif x2
ret
ENDPROC(idmap_cpu_replace_ttbr1)