accel/tcg: Don't treat invalid TLB entries as needing recheck

In get_page_addr_code() when we check whether the TLB entry
is marked as TLB_RECHECK, we should not go down that code
path if the TLB entry is not valid at all (ie the TLB_INVALID
bit is set).

Tested-by: Laurent Vivier <laurent@vivier.eu>
Reported-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20180629161731.16239-1-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

accel/tcg/cputlb.c

@@ -963,7 +963,8 @@ tb_page_addr_t get_page_addr_code(CPUArchState *env, target_ulong addr)
         }
     }
 
-    if (unlikely(env->tlb_table[mmu_idx][index].addr_code & TLB_RECHECK)) {
+    if (unlikely((env->tlb_table[mmu_idx][index].addr_code &
+                  (TLB_RECHECK | TLB_INVALID_MASK)) == TLB_RECHECK)) {
         /*
          * This is a TLB_RECHECK access, where the MMU protection
          * covers a smaller range than a target page, and we must