ARC: Handle zero-overhead-loop in unaligned access handler

commit c11eb222fd7d4db91196121dbf854178505d2751 upstream.

If a load or store is the last instruction in a zero-overhead-loop, and
it's misaligned, the loop would execute only once.

This fixes that problem.

Signed-off-by: Mischa Jonker <mjonker@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/arch/arc/kernel/unaligned.c b/arch/arc/kernel/unaligned.c
index 4cd81633febd..116d3e09b5b5 100644
--- a/arch/arc/kernel/unaligned.c
+++ b/arch/arc/kernel/unaligned.c
@@ -233,6 +233,12 @@ int misaligned_fixup(unsigned long address, struct pt_regs *regs,
                 regs->status32 &= ~STATUS_DE_MASK;
         } else {
                 regs->ret += state.instr_len;
+
+                /* handle zero-overhead-loop */
+                if ((regs->ret == regs->lp_end) && (regs->lp_count)) {
+                        regs->ret = regs->lp_start;
+                        regs->lp_count--;
+                }
         }
 
         return 0;