ARC: Handle zero-overhead-loop in unaligned access handler
authorMischa Jonker <mjonker@synopsys.com>
Thu, 26 Sep 2013 13:44:56 +0000 (15:44 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 18 Oct 2013 14:45:45 +0000 (07:45 -0700)
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>
arch/arc/kernel/unaligned.c

index 4cd81633febd2c8dc91aa290837feed7370d06ce..116d3e09b5b55f1a977859d2313496ff497442d7 100644 (file)
@@ -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;