diff options
| -rw-r--r-- | cpu-exec.c | 2 | ||||
| -rw-r--r-- | target-i386/cpu.h | 1 | ||||
| -rw-r--r-- | target-i386/helper.c | 39 |
3 files changed, 42 insertions, 0 deletions
@@ -360,6 +360,8 @@ int cpu_exec(CPUState *env1) env->exception_is_int, env->error_code, env->exception_next_eip, 0); + /* successfully delivered */ + env->old_exception = -1; #elif defined(TARGET_PPC) do_interrupt(env); #elif defined(TARGET_MIPS) diff --git a/target-i386/cpu.h b/target-i386/cpu.h index 1eb546e..104f31e 100644 --- a/target-i386/cpu.h +++ b/target-i386/cpu.h @@ -515,6 +515,7 @@ typedef struct CPUX86State { uint32_t smbase; int interrupt_request; int user_mode_only; /* user mode only simulation */ + int old_exception; /* exception in flight */ CPU_COMMON diff --git a/target-i386/helper.c b/target-i386/helper.c index 1d62f6b..70370fc 100644 --- a/target-i386/helper.c +++ b/target-i386/helper.c @@ -1193,6 +1193,40 @@ void do_interrupt(int intno, int is_int, int error_code, } /* + * Check nested exceptions and change to double or triple fault if + * needed. It should only be called, if this is not an interrupt. + * Returns the new exception number. + */ +int check_exception(int intno, int *error_code) +{ + char first_contributory = env->old_exception == 0 || + (env->old_exception >= 10 && + env->old_exception <= 13); + char second_contributory = intno == 0 || + (intno >= 10 && intno <= 13); + + if (loglevel & CPU_LOG_INT) + fprintf(logfile, "check_exception old: %x new %x\n", + env->old_exception, intno); + + if (env->old_exception == EXCP08_DBLE) + cpu_abort(env, "triple fault"); + + if ((first_contributory && second_contributory) + || (env->old_exception == EXCP0E_PAGE && + (second_contributory || (intno == EXCP0E_PAGE)))) { + intno = EXCP08_DBLE; + *error_code = 0; + } + + if (second_contributory || (intno == EXCP0E_PAGE) || + (intno == EXCP08_DBLE)) + env->old_exception = intno; + + return intno; +} + +/* * Signal an interruption. It is executed in the main CPU loop. * is_int is TRUE if coming from the int instruction. next_eip is the * EIP value AFTER the interrupt instruction. It is only relevant if @@ -1201,6 +1235,9 @@ void do_interrupt(int intno, int is_int, int error_code, void raise_interrupt(int intno, int is_int, int error_code, int next_eip_addend) { + if (!is_int) + intno = check_exception(intno, &error_code); + env->exception_index = intno; env->error_code = error_code; env->exception_is_int = is_int; @@ -1211,6 +1248,8 @@ void raise_interrupt(int intno, int is_int, int error_code, /* same as raise_exception_err, but do not restore global registers */ static void raise_exception_err_norestore(int exception_index, int error_code) { + exception_index = check_exception(exception_index, &error_code); + env->exception_index = exception_index; env->error_code = error_code; env->exception_is_int = 0; |