powerpc/powernv: Use kernel crash path for machine checks

[platform/kernel/linux-exynos.git] / arch / powerpc / platforms / powernv / opal.c

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index d246f91..65c79ec 100644 (file)
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -36,6 +36,7 @@
 #include <asm/firmware.h>
 #include <asm/mce.h>
 #include <asm/imc-pmu.h>
+#include <asm/bug.h>
 
 #include "powernv.h"
 
@@ -425,17 +426,36 @@ static int opal_recover_mce(struct pt_regs *regs,
                /* Fatal machine check */
                pr_err("Machine check interrupt is fatal\n");
                recovered = 0;
-       } else if ((evt->severity == MCE_SEV_ERROR_SYNC) &&
-                       (user_mode(regs) && !is_global_init(current))) {
+       }
+
+       if (!recovered && evt->severity == MCE_SEV_ERROR_SYNC) {
                /*
-                * For now, kill the task if we have received exception when
-                * in userspace.
+                * Try to kill processes if we get a synchronous machine check
+                * (e.g., one caused by execution of this instruction). This
+                * will devolve into a panic if we try to kill init or are in
+                * an interrupt etc.
                 *
                 * TODO: Queue up this address for hwpoisioning later.
+                * TODO: This is not quite right for d-side machine
+                *       checks ->nip is not necessarily the important
+                *       address.
                 */
-               _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
-               recovered = 1;
+               if ((user_mode(regs))) {
+                       _exception(SIGBUS, regs, BUS_MCEERR_AR, regs->nip);
+                       recovered = 1;
+               } else if (die_will_crash()) {
+                       /*
+                        * die() would kill the kernel, so better to go via
+                        * the platform reboot code that will log the
+                        * machine check.
+                        */
+                       recovered = 0;
+               } else {
+                       die("Machine check", regs, SIGBUS);
+                       recovered = 1;
+               }
        }
+
        return recovered;
 }