From: Richard Henderson <richard.henderson@linaro.org>
Date: Wed, 3 Apr 2024 05:28:20 +0000 (-1000)
Subject: accel/tcg: Cap the translation block when we encounter mmio
X-Git-Tag: v9.1.0-rc0~106^2~29
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=ddfa9f11766c532209d4ce848c12761d28730338;p=thirdparty%2Fqemu.git

accel/tcg: Cap the translation block when we encounter mmio

Do not allow translation to proceed beyond one insn with mmio,
as we will not be caching the TranslationBlock.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---

diff --git a/accel/tcg/translator.c b/accel/tcg/translator.c
index 0848026935a..18138c61e19 100644
--- a/accel/tcg/translator.c
+++ b/accel/tcg/translator.c
@@ -240,6 +240,8 @@ static bool translator_ld(CPUArchState *env, DisasContextBase *db,
 
     /* Use slow path if first page is MMIO. */
     if (unlikely(tb_page_addr0(tb) == -1)) {
+        /* We capped translation with first page MMIO in tb_gen_code. */
+        tcg_debug_assert(db->max_insns == 1);
         return false;
     }
 
@@ -288,6 +290,8 @@ static bool translator_ld(CPUArchState *env, DisasContextBase *db,
         if (unlikely(new_page1 == -1)) {
             tb_unlock_pages(tb);
             tb_set_page_addr0(tb, -1);
+            /* Require that this be the final insn. */
+            db->max_insns = db->num_insns;
             return false;
         }