diff mbox series

[PULL,22/26] target/arm: Don't set EXC_RETURN.ES if Security Extension not present

Message ID 20230123133553.2171158-23-peter.maydell@linaro.org (mailing list archive)
State New, archived
Headers show
Series [PULL,01/26] target/arm: Widen cnthctl_el2 to uint64_t | expand

Commit Message

Peter Maydell Jan. 23, 2023, 1:35 p.m. UTC 
In v7m_exception_taken(), for v8M we set the EXC_RETURN.ES bit if
either the exception targets Secure or if the CPU doesn't implement
the Security Extension.  This is incorrect: the v8M Arm ARM specifies
that the ES bit should be RES0 if the Security Extension is not
implemented, and the pseudocode agrees.

Remove the incorrect condition, so that we leave the ES bit 0
if the Security Extension isn't implemented.

This doesn't have any guest-visible effects for our current set of
emulated CPUs, because all our v8M CPUs implement the Security
Extension; but it's worth fixing in case we add a v8M CPU without
the extension in future.

Reported-by: Igor Kotrasinski <i.kotrasinsk@samsung.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/m_helper.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/target/arm/m_helper.c b/target/arm/m_helper.c
index d87b9ecd123..e7e746ea182 100644
--- a/target/arm/m_helper.c
+++ b/target/arm/m_helper.c
@@ -879,7 +879,7 @@  static void v7m_exception_taken(ARMCPU *cpu, uint32_t lr, bool dotailchain,
         }
 
         lr &= ~R_V7M_EXCRET_ES_MASK;
-        if (targets_secure || !arm_feature(env, ARM_FEATURE_M_SECURITY)) {
+        if (targets_secure) {
             lr |= R_V7M_EXCRET_ES_MASK;
         }
         lr &= ~R_V7M_EXCRET_SPSEL_MASK;