From: Peter Maydell <peter.maydell@linaro.org>
Date: Tue, 23 Feb 2016 15:36:44 +0000 (+0000)
Subject: target-arm: Forbid mode switch to Mon from Secure EL1
X-Git-Tag: v2.6.0-rc0~68^2~12
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=58ae2d1f037fae1d90eed4522053a85d79edfbec;p=thirdparty%2Fqemu.git

target-arm: Forbid mode switch to Mon from Secure EL1

In v8 trying to switch mode to Mon from Secure EL1 is an
illegal mode switch. (In v7 this is impossible as all secure
modes except User are at EL3.) We can handle this case by
making a switch to Mon valid only if the current EL is 3,
which then gives the correct answer whether EL3 is AArch32
or AArch64.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergey Fedorov <serge.fdrv@gmail.com>
Message-id: 1455556977-3644-9-git-send-email-peter.maydell@linaro.org
---

diff --git a/target-arm/helper.c b/target-arm/helper.c
index c43d66fd8db..5926b15506a 100644
--- a/target-arm/helper.c
+++ b/target-arm/helper.c
@@ -5222,7 +5222,7 @@ static int bad_mode_switch(CPUARMState *env, int mode)
         return !arm_feature(env, ARM_FEATURE_EL2)
             || arm_current_el(env) < 2 || arm_is_secure(env);
     case ARM_CPU_MODE_MON:
-        return !arm_is_secure(env);
+        return arm_current_el(env) < 3;
     default:
         return 1;
     }