Re: [Qemu-arm] [Qemu-devel] [PATCH for-3.0] target/arm: Use correct mmu_idx for exception-return unstacking

[Richard Henderson]

On 07/09/2018 05:45 AM, Peter Maydell wrote:
> 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 <address@hidden>
> Signed-off-by: Peter Maydell <address@hidden>
> ---
>  target/arm/helper.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)

Reviewed-by: Richard Henderson <address@hidden>


r~