arm64: sdei: move uaccess logic to arch/arm64/

[linux-2.6-microblaze.git] / arch / arm64 / kernel / sdei.c

diff --git a/arch/arm64/kernel/sdei.c b/arch/arm64/kernel/sdei.c
index 7689f20..4a5f246 100644 (file)
--- a/arch/arm64/kernel/sdei.c
+++ b/arch/arm64/kernel/sdei.c
@@ -178,12 +178,6 @@ static __kprobes unsigned long _sdei_handler(struct pt_regs *regs,
                sdei_api_event_context(i, &regs->regs[i]);
        }
 
-       /*
-        * We didn't take an exception to get here, set PAN. UAO will be cleared
-        * by sdei_event_handler()s force_uaccess_begin() call.
-        */
-       __uaccess_enable_hw_pan();
-
        err = sdei_event_handler(regs, arg);
        if (err)
                return SDEI_EV_FAILED;
@@ -227,6 +221,16 @@ asmlinkage __kprobes notrace unsigned long
 __sdei_handler(struct pt_regs *regs, struct sdei_registered_event *arg)
 {
        unsigned long ret;
+       mm_segment_t orig_addr_limit;
+
+       /*
+        * We didn't take an exception to get here, so the HW hasn't set PAN or
+        * cleared UAO, and the exception entry code hasn't reset addr_limit.
+        * Set PAN, then use force_uaccess_begin() to clear UAO and reset
+        * addr_limit.
+        */
+       __uaccess_enable_hw_pan();
+       orig_addr_limit = force_uaccess_begin();
 
        nmi_enter();
 
@@ -234,5 +238,7 @@ __sdei_handler(struct pt_regs *regs, struct sdei_registered_event *arg)
 
        nmi_exit();
 
+       force_uaccess_end(orig_addr_limit);
+
        return ret;
 }