Blackfin: add workaround for anomaly 05000461

Returning too fast with a bad RETI can trigger false errors.

Signed-off-by: Robin Getz <robin.getz@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c
index 0d04a4732b1f..778a75655a0c 100644
--- a/arch/blackfin/kernel/traps.c
+++ b/arch/blackfin/kernel/traps.c
@@ -594,6 +594,9 @@ asmlinkage void trap_c(struct pt_regs *fp)
                 force_sig_info(sig, &info, current);
         }
 
+        if (ANOMALY_05000461 && trapnr == VEC_HWERR && !access_ok(VERIFY_READ, fp->pc, 8))
+                fp->pc = SAFE_USER_INSTRUCTION;
+
         trace_buffer_restore(j);
         return;
 }