From: Richard Henderson <richard.henderson@linaro.org>
Date: Fri, 4 Jul 2025 14:19:24 +0000 (-0600)
Subject: target/arm: Fix SME vs AdvSIMD exception priority
X-Git-Tag: v10.1.0-rc0~29^2~106
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f9b0f69304071384b12912bf9dd78e9ffd261cec;p=thirdparty%2Fqemu.git

target/arm: Fix SME vs AdvSIMD exception priority

We failed to raise an exception when
sme_excp_el == 0 and fp_excp_el == 1.

Cc: qemu-stable@nongnu.org
Fixes: 3d74825f4d6 ("target/arm: Add SME enablement checks")
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20250704142112.1018902-2-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---

diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 815225b1301..5c44a5dece9 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -1488,7 +1488,8 @@ bool sme_enabled_check(DisasContext *s)
      * to be zero when fp_excp_el has priority.  This is because we need
      * sme_excp_el by itself for cpregs access checks.
      */
-    if (!s->fp_excp_el || s->sme_excp_el < s->fp_excp_el) {
+    if (s->sme_excp_el
+        && (!s->fp_excp_el || s->sme_excp_el <= s->fp_excp_el)) {
         bool ret = sme_access_check(s);
         s->fp_access_checked = (ret ? 1 : -1);
         return ret;