diff options
Diffstat (limited to 'arch/arm64/mm/fault.c')
| -rw-r--r-- | arch/arm64/mm/fault.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index 53d9159662fe..0f8788374815 100644 --- 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> @@ -670,9 +672,17 @@ asmlinkage int __exception do_debug_exception(unsigned long addr, NOKPROBE_SYMBOL(do_debug_exception); #ifdef CONFIG_ARM64_PAN -void cpu_enable_pan(void *__unused) +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 */ @@ -683,8 +693,9 @@ void cpu_enable_pan(void *__unused) * We need to enable the feature at runtime (instead of adding it to * PSR_MODE_EL1h) as the feature may not be implemented by the cpu. */ -void cpu_enable_uao(void *__unused) +int cpu_enable_uao(void *__unused) { asm(SET_PSTATE_UAO(1)); + return 0; } #endif /* CONFIG_ARM64_UAO */ |