diff options
| author | Edgar E. Iglesias <edgar.iglesias@xilinx.com> | 2014-05-27 17:09:53 +0100 |
|---|---|---|
| committer | Peter Maydell <peter.maydell@linaro.org> | 2014-05-27 17:09:53 +0100 |
| commit | 7ab6c10d008c79d92b0b62e36fb0edc4066d37d6 (patch) | |
| tree | 9708432d41a146758f33e47af1c9750ef2fc37cd | |
| parent | 81547d663030cfd3508bc8126d015030ddbe9c96 (diff) | |
target-arm: A64: Forbid ERET to higher or unimplemented ELs
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 1400980132-25949-18-git-send-email-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
| -rw-r--r-- | target-arm/op_helper.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/target-arm/op_helper.c b/target-arm/op_helper.c index c2b4bf0fd7..e95a7f401f 100644 --- a/target-arm/op_helper.c +++ b/target-arm/op_helper.c @@ -389,6 +389,7 @@ void HELPER(exception_return)(CPUARMState *env) unsigned int spsr_idx = aarch64_banked_spsr_index(1); uint32_t spsr = env->banked_spsr[spsr_idx]; int new_el, i; + int cur_el = arm_current_pl(env); if (env->pstate & PSTATE_SP) { env->sp_el[1] = env->xregs[31]; @@ -410,8 +411,11 @@ void HELPER(exception_return)(CPUARMState *env) env->regs[15] = env->elr_el[1] & ~0x1; } else { new_el = extract32(spsr, 2, 2); - if (new_el > 1) { - /* Return to unimplemented EL */ + if (new_el > cur_el + || (new_el == 2 && !arm_feature(env, ARM_FEATURE_EL2))) { + /* Disallow return to an EL which is unimplemented or higher + * than the current one. + */ goto illegal_return; } if (extract32(spsr, 1, 1)) { |