diff options
| author | Peter Maydell <peter.maydell@linaro.org> | 2018-07-09 13:45:35 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2018-07-10 10:54:40 +0100 |
| commit | 2b83714d4ea659899069a4b94aa2dfadc847a013 (patch) | |
| tree | 08c6699e8b22ece28fc957c3fb68eaabc28048c4 /target | |
| parent | 3a340e84375145fa32ce68e0b7b58d964487336b (diff) | |
target/arm: Use correct mmu_idx for exception-return unstacking
For M-profile exception returns, the mmu index to use for exception
return unstacking is supposed to be that of wherever we are returning to:
* if returning to handler mode, privileged
* if returning to thread mode, privileged or unprivileged depending on
CONTROL.nPRIV for the destination security state
We were passing the wrong thing as the 'priv' argument to
arm_v7m_mmu_idx_for_secstate_and_priv(). The effect was that guests
which programmed the MPU to behave differently for privileged and
unprivileged code could get spurious MemManage Unstack exceptions.
Reported-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20180709124535.1116-1-peter.maydell@linaro.org
Diffstat (limited to 'target')
| -rw-r--r-- | target/arm/helper.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/target/arm/helper.c b/target/arm/helper.c index a2ac96084e..0604a0efbe 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -7171,9 +7171,11 @@ static void do_v7m_exception_exit(ARMCPU *cpu) uint32_t frameptr = *frame_sp_p; bool pop_ok = true; ARMMMUIdx mmu_idx; + bool return_to_priv = return_to_handler || + !(env->v7m.control[return_to_secure] & R_V7M_CONTROL_NPRIV_MASK); mmu_idx = arm_v7m_mmu_idx_for_secstate_and_priv(env, return_to_secure, - !return_to_handler); + return_to_priv); if (!QEMU_IS_ALIGNED(frameptr, 8) && arm_feature(env, ARM_FEATURE_V8)) { |