From 1e5da7e55332c76da2057e6d5298d7bf1733f104 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Fri, 16 Dec 2022 15:24:10 +0000 Subject: target/arm: Don't set EXC_RETURN.ES if Security Extension not present 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 Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson --- target/arm/m_helper.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/target/arm/m_helper.c b/target/arm/m_helper.c index d87b9ecd12..e7e746ea18 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; -- cgit v1.2.3