diff options
| -rw-r--r-- | target/arm/helper.c | 35 |
1 files changed, 23 insertions, 12 deletions
diff --git a/target/arm/helper.c b/target/arm/helper.c index 6062f380d4..c713eea424 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -6419,7 +6419,8 @@ static uint32_t arm_v7m_load_vector(ARMCPU *cpu, int exc, bool targets_secure) return addr; } -static void v7m_push_callee_stack(ARMCPU *cpu, uint32_t lr, bool dotailchain) +static void v7m_push_callee_stack(ARMCPU *cpu, uint32_t lr, bool dotailchain, + bool ignore_faults) { /* For v8M, push the callee-saves register part of the stack frame. * Compare the v8M pseudocode PushCalleeStack(). @@ -6453,7 +6454,8 @@ static void v7m_push_callee_stack(ARMCPU *cpu, uint32_t lr, bool dotailchain) *frame_sp_p = frameptr; } -static void v7m_exception_taken(ARMCPU *cpu, uint32_t lr, bool dotailchain) +static void v7m_exception_taken(ARMCPU *cpu, uint32_t lr, bool dotailchain, + bool ignore_stackfaults) { /* Do the "take the exception" parts of exception entry, * but not the pushing of state to the stack. This is @@ -6490,7 +6492,8 @@ static void v7m_exception_taken(ARMCPU *cpu, uint32_t lr, bool dotailchain) */ if (lr & R_V7M_EXCRET_DCRS_MASK && !(dotailchain && (lr & R_V7M_EXCRET_ES_MASK))) { - v7m_push_callee_stack(cpu, lr, dotailchain); + v7m_push_callee_stack(cpu, lr, dotailchain, + ignore_stackfaults); } lr |= R_V7M_EXCRET_DCRS_MASK; } @@ -6551,10 +6554,13 @@ static void v7m_exception_taken(ARMCPU *cpu, uint32_t lr, bool dotailchain) env->thumb = addr & 1; } -static void v7m_push_stack(ARMCPU *cpu) +static bool v7m_push_stack(ARMCPU *cpu) { /* Do the "set up stack frame" part of exception entry, * similar to pseudocode PushStack(). + * Return true if we generate a derived exception (and so + * should ignore further stack faults trying to process + * that derived exception.) */ CPUARMState *env = &cpu->env; uint32_t xpsr = xpsr_read(env); @@ -6574,6 +6580,8 @@ static void v7m_push_stack(ARMCPU *cpu) v7m_push(env, env->regs[2]); v7m_push(env, env->regs[1]); v7m_push(env, env->regs[0]); + + return false; } static void do_v7m_exception_exit(ARMCPU *cpu) @@ -6719,7 +6727,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu) if (sfault) { env->v7m.sfsr |= R_V7M_SFSR_INVER_MASK; armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_SECURE, false); - v7m_exception_taken(cpu, excret, true); + v7m_exception_taken(cpu, excret, true, false); qemu_log_mask(CPU_LOG_INT, "...taking SecureFault on existing " "stackframe: failed EXC_RETURN.ES validity check\n"); return; @@ -6731,7 +6739,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu) */ env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_INVPC_MASK; armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE, env->v7m.secure); - v7m_exception_taken(cpu, excret, true); + v7m_exception_taken(cpu, excret, true, false); qemu_log_mask(CPU_LOG_INT, "...taking UsageFault on existing " "stackframe: failed exception return integrity check\n"); return; @@ -6779,7 +6787,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu) /* Take a SecureFault on the current stack */ env->v7m.sfsr |= R_V7M_SFSR_INVIS_MASK; armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_SECURE, false); - v7m_exception_taken(cpu, excret, true); + v7m_exception_taken(cpu, excret, true, false); qemu_log_mask(CPU_LOG_INT, "...taking SecureFault on existing " "stackframe: failed exception return integrity " "signature check\n"); @@ -6844,7 +6852,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu) armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE, env->v7m.secure); env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_INVPC_MASK; - v7m_exception_taken(cpu, excret, true); + v7m_exception_taken(cpu, excret, true, false); qemu_log_mask(CPU_LOG_INT, "...taking UsageFault on existing " "stackframe: failed exception return integrity " "check\n"); @@ -6877,11 +6885,13 @@ static void do_v7m_exception_exit(ARMCPU *cpu) /* Take an INVPC UsageFault by pushing the stack again; * we know we're v7M so this is never a Secure UsageFault. */ + bool ignore_stackfaults; + assert(!arm_feature(env, ARM_FEATURE_V8)); armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE, false); env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_INVPC_MASK; - v7m_push_stack(cpu); - v7m_exception_taken(cpu, excret, false); + ignore_stackfaults = v7m_push_stack(cpu); + v7m_exception_taken(cpu, excret, false, ignore_stackfaults); qemu_log_mask(CPU_LOG_INT, "...taking UsageFault on new stackframe: " "failed exception return integrity check\n"); return; @@ -7122,6 +7132,7 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) ARMCPU *cpu = ARM_CPU(cs); CPUARMState *env = &cpu->env; uint32_t lr; + bool ignore_stackfaults; arm_log_exception(cs->exception_index); @@ -7296,8 +7307,8 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) lr |= R_V7M_EXCRET_MODE_MASK; } - v7m_push_stack(cpu); - v7m_exception_taken(cpu, lr, false); + ignore_stackfaults = v7m_push_stack(cpu); + v7m_exception_taken(cpu, lr, false, ignore_stackfaults); qemu_log_mask(CPU_LOG_INT, "... as %d\n", env->v7m.exception); } |