powerpc: Save DAR and DSISR in pt_regs on MCE

We were not saving DAR and DSISR on MCE. Save then and also print the values
along with exception details in xmon.

Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

2 files changed, 10 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index 80d56f094a0d..e6eba1bf61ad 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -693,9 +693,18 @@ slb_miss_user_pseries:
         .align  7
         .globl machine_check_common
 machine_check_common:
+
+        mfspr   r10,SPRN_DAR
+        std     r10,PACA_EXGEN+EX_DAR(r13)
+        mfspr   r10,SPRN_DSISR
+        stw     r10,PACA_EXGEN+EX_DSISR(r13)
         EXCEPTION_PROLOG_COMMON(0x200, PACA_EXMC)
         FINISH_NAP
         DISABLE_INTS
+        ld      r3,PACA_EXGEN+EX_DAR(r13)
+        lwz     r4,PACA_EXGEN+EX_DSISR(r13)
+        std     r3,_DAR(r1)
+        std     r4,_DSISR(r1)
         bl      .save_nvgprs
         addi    r3,r1,STACK_FRAME_OVERHEAD
         bl      .machine_check_exception
diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
index 13f85defabed..51e237c4648f 100644
--- a/arch/powerpc/xmon/xmon.c
+++ b/arch/powerpc/xmon/xmon.c
@@ -1430,7 +1430,7 @@ static void excprint(struct pt_regs *fp)
         printf("    sp: %lx\n", fp->gpr[1]);
         printf("   msr: %lx\n", fp->msr);
 
-        if (trap == 0x300 || trap == 0x380 || trap == 0x600) {
+        if (trap == 0x300 || trap == 0x380 || trap == 0x600 || trap == 0x200) {
                 printf("   dar: %lx\n", fp->dar);
                 if (trap != 0x380)
                         printf(" dsisr: %lx\n", fp->dsisr);