sparc64: fix fault handling in NGbzero.S and GENbzero.S

When any of the functions contained in NGbzero.S and GENbzero.S
vector through *bzero_from_clear_user, we may end up taking a
fault when executing one of the store alternate address space
instructions. If this happens, the exception handler does not
restore the %asi register.

This commit fixes the issue by introducing a new exception
handler that ensures the %asi register is restored when
a fault is handled.

Orabug: 25577560

Signed-off-by: Dave Aldridge <david.j.aldridge@oracle.com>
Reviewed-by: Rob Gardner <rob.gardner@oracle.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 2 insertions, 2 deletions

diff --git a/arch/sparc/lib/GENbzero.S b/arch/sparc/lib/GENbzero.S
index 8e7a843ddd88..2fbf6297d57c 100644
--- a/arch/sparc/lib/GENbzero.S
+++ b/arch/sparc/lib/GENbzero.S
@@ -8,7 +8,7 @@
 98:     x,y;                    \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_o1;   \
+        .word 98b, __retl_o1_asi;\
         .text;                  \
         .align 4;
 
diff --git a/arch/sparc/lib/NGbzero.S b/arch/sparc/lib/NGbzero.S
index beab29bf419b..33053bdf3766 100644
--- a/arch/sparc/lib/NGbzero.S
+++ b/arch/sparc/lib/NGbzero.S
@@ -8,7 +8,7 @@
 98:     x,y;                    \
         .section __ex_table,"a";\
         .align 4;               \
-        .word 98b, __retl_o1;   \
+        .word 98b, __retl_o1_asi;\
         .text;                  \
         .align 4;