diff options
Diffstat (limited to 'user-exec.c')
| -rw-r--r-- | user-exec.c | 41 |
1 files changed, 29 insertions, 12 deletions
diff --git a/user-exec.c b/user-exec.c index c809daaa87..efd34a6ee4 100644 --- a/user-exec.c +++ b/user-exec.c @@ -55,7 +55,7 @@ static void exception_action(CPUState *cpu) /* exit the current TB from a signal handler. The host registers are restored in a state compatible with the CPU emulator */ -void cpu_resume_from_signal(CPUState *cpu, void *puc) +static void cpu_exit_tb_from_sighandler(CPUState *cpu, void *puc) { #ifdef __linux__ struct ucontext *uc = puc; @@ -63,20 +63,18 @@ void cpu_resume_from_signal(CPUState *cpu, void *puc) struct sigcontext *uc = puc; #endif - if (puc) { - /* XXX: use siglongjmp ? */ + /* XXX: use siglongjmp ? */ #ifdef __linux__ #ifdef __ia64 - sigprocmask(SIG_SETMASK, (sigset_t *)&uc->uc_sigmask, NULL); + sigprocmask(SIG_SETMASK, (sigset_t *)&uc->uc_sigmask, NULL); #else - sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL); + sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL); #endif #elif defined(__OpenBSD__) - sigprocmask(SIG_SETMASK, &uc->sc_mask, NULL); + sigprocmask(SIG_SETMASK, &uc->sc_mask, NULL); #endif - } - cpu->exception_index = -1; - siglongjmp(cpu->jmp_env, 1); + + cpu_resume_from_signal(cpu, NULL); } /* 'pc' is the host PC at which the exception was raised. 'address' is @@ -96,9 +94,28 @@ static inline int handle_cpu_signal(uintptr_t pc, unsigned long address, pc, address, is_write, *(unsigned long *)old_set); #endif /* XXX: locking issue */ - if (is_write && h2g_valid(address) - && page_unprotect(h2g(address), pc, puc)) { - return 1; + if (is_write && h2g_valid(address)) { + switch (page_unprotect(h2g(address), pc)) { + case 0: + /* Fault not caused by a page marked unwritable to protect + * cached translations, must be the guest binary's problem + */ + break; + case 1: + /* Fault caused by protection of cached translation; TBs + * invalidated, so resume execution + */ + return 1; + case 2: + /* Fault caused by protection of cached translation, and the + * currently executing TB was modified and must be exited + * immediately. + */ + cpu_exit_tb_from_sighandler(current_cpu, puc); + g_assert_not_reached(); + default: + g_assert_not_reached(); + } } /* Convert forcefully to guest address space, invalid addresses |