Merge remote-tracking branches 'spi/fix/dt', 'spi/fix/fsl-dspi' and 'spi/fix/fsl...

[cascardo/linux.git] / arch / arm64 / mm / fault.c

diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
index 3e9ff9b..0f87883 100644 (file)
--- a/arch/arm64/mm/fault.c
+++ b/arch/arm64/mm/fault.c
@@ -29,7 +29,9 @@
 #include <linux/sched.h>
 #include <linux/highmem.h>
 #include <linux/perf_event.h>
+#include <linux/preempt.h>
 
+#include <asm/bug.h>
 #include <asm/cpufeature.h>
 #include <asm/exception.h>
 #include <asm/debug-monitors.h>
@@ -672,7 +674,14 @@ NOKPROBE_SYMBOL(do_debug_exception);
 #ifdef CONFIG_ARM64_PAN
 int cpu_enable_pan(void *__unused)
 {
+       /*
+        * We modify PSTATE. This won't work from irq context as the PSTATE
+        * is discarded once we return from the exception.
+        */
+       WARN_ON_ONCE(in_interrupt());
+
        config_sctlr_el1(SCTLR_EL1_SPAN, 0);
+       asm(SET_PSTATE_PAN(1));
        return 0;
 }
 #endif /* CONFIG_ARM64_PAN */