diff --git a/arch/um/include/shared/longjmp.h b/arch/um/include/shared/longjmp.h index b3315c1f198b..85a1cc290ecb 100644 --- a/arch/um/include/shared/longjmp.h +++ b/arch/um/include/shared/longjmp.h @@ -18,7 +18,7 @@ extern void longjmp(jmp_buf, int); enable = get_signals(); \ n = setjmp(*buf); \ if(n != 0) \ - set_signals(enable); \ + set_signals_trace(enable); \ n; }) #endif diff --git a/arch/um/include/shared/os.h b/arch/um/include/shared/os.h index 4a62ac4251a5..fa1909365666 100644 --- a/arch/um/include/shared/os.h +++ b/arch/um/include/shared/os.h @@ -232,6 +232,7 @@ extern void block_signals(void); extern void unblock_signals(void); extern int get_signals(void); extern int set_signals(int enable); +extern int set_signals_trace(int enable); extern int os_is_signal_stack(void); extern void deliver_alarm(void); @@ -317,4 +318,10 @@ extern unsigned long os_get_top_address(void); long syscall(long number, ...); +/* irqflags tracing */ +extern void block_signals_trace(void); +extern void unblock_signals_trace(void); +extern void um_trace_signals_on(void); +extern void um_trace_signals_off(void); + #endif diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c index 57acbd67d85d..3a8012520e22 100644 --- a/arch/um/kernel/signal.c +++ b/arch/um/kernel/signal.c @@ -6,15 +6,43 @@ #include #include #include +#include #include #include #include #include #include +#include EXPORT_SYMBOL(block_signals); EXPORT_SYMBOL(unblock_signals); +void block_signals_trace(void) +{ + block_signals(); + if (current_thread_info()) + trace_hardirqs_off(); +} + +void unblock_signals_trace(void) +{ + if (current_thread_info()) + trace_hardirqs_on(); + unblock_signals(); +} + +void um_trace_signals_on(void) +{ + if (current_thread_info()) + trace_hardirqs_on(); +} + +void um_trace_signals_off(void) +{ + if (current_thread_info()) + trace_hardirqs_off(); +} + /* * OK, we're invoking a handler */ diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c index 29e7f5f9f188..ace71f805700 100644 --- a/arch/um/kernel/skas/mmu.c +++ b/arch/um/kernel/skas/mmu.c @@ -63,12 +63,12 @@ int init_new_context(struct task_struct *task, struct mm_struct *mm) if (current->mm != NULL && current->mm != &init_mm) from_mm = ¤t->mm->context; - block_signals(); + block_signals_trace(); if (from_mm) to_mm->id.u.pid = copy_context_skas0(stack, from_mm->id.u.pid); else to_mm->id.u.pid = start_userspace(stack); - unblock_signals(); + unblock_signals_trace(); if (to_mm->id.u.pid < 0) { ret = to_mm->id.u.pid; diff --git a/arch/um/kernel/skas/process.c b/arch/um/kernel/skas/process.c index d4dbf08722d6..404914627dd6 100644 --- a/arch/um/kernel/skas/process.c +++ b/arch/um/kernel/skas/process.c @@ -19,7 +19,7 @@ static int __init start_kernel_proc(void *unused) { int pid; - block_signals(); + block_signals_trace(); pid = os_getpid(); cpu_tasks[0].pid = pid; diff --git a/arch/um/os-Linux/main.c b/arch/um/os-Linux/main.c index f1fee2b91239..6d098e712839 100644 --- a/arch/um/os-Linux/main.c +++ b/arch/um/os-Linux/main.c @@ -170,7 +170,7 @@ int __init main(int argc, char **argv, char **envp) * that they won't be delivered after the exec, when * they are definitely not expected. */ - unblock_signals(); + unblock_signals_trace(); os_info("\n"); /* Reboot */ diff --git a/arch/um/os-Linux/sigio.c b/arch/um/os-Linux/sigio.c index 46e762f926eb..21b226aa1041 100644 --- a/arch/um/os-Linux/sigio.c +++ b/arch/um/os-Linux/sigio.c @@ -132,7 +132,7 @@ static void update_thread(void) int n; char c; - flags = set_signals(0); + flags = set_signals_trace(0); CATCH_EINTR(n = write(sigio_private[0], &c, sizeof(c))); if (n != sizeof(c)) { printk(UM_KERN_ERR "update_thread : write failed, err = %d\n", @@ -147,7 +147,7 @@ static void update_thread(void) goto fail; } - set_signals(flags); + set_signals_trace(flags); return; fail: /* Critical section start */ @@ -161,7 +161,7 @@ static void update_thread(void) close(write_sigio_fds[0]); close(write_sigio_fds[1]); /* Critical section end */ - set_signals(flags); + set_signals_trace(flags); } int add_sigio_fd(int fd) diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c index 4cd88b5b9006..bde54c4a27da 100644 --- a/arch/um/os-Linux/signal.c +++ b/arch/um/os-Linux/signal.c @@ -43,7 +43,7 @@ static void sig_handler_common(int sig, struct siginfo *si, mcontext_t *mc) /* enable signals if sig isn't IRQ signal */ if ((sig != SIGIO) && (sig != SIGWINCH)) - unblock_signals(); + unblock_signals_trace(); (*sig_info[sig])(sig, si, &r); @@ -76,11 +76,11 @@ void sig_handler(int sig, struct siginfo *si, mcontext_t *mc) return; } - block_signals(); + block_signals_trace(); sig_handler_common(sig, si, mc); - set_signals(enabled); + set_signals_trace(enabled); } static void timer_real_alarm_handler(mcontext_t *mc) @@ -104,7 +104,7 @@ void timer_alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc) return; } - block_signals(); + block_signals_trace(); signals_active |= SIGALRM_MASK; @@ -112,7 +112,7 @@ void timer_alarm_handler(int sig, struct siginfo *unused_si, mcontext_t *mc) signals_active &= ~SIGALRM_MASK; - set_signals(enabled); + set_signals_trace(enabled); } void deliver_alarm(void) { @@ -253,6 +253,8 @@ void unblock_signals(void) if (signals_enabled == 1) return; + signals_enabled = 1; + /* * We loop because the IRQ handler returns with interrupts off. So, * interrupts may have arrived and we need to re-enable them and @@ -262,12 +264,9 @@ void unblock_signals(void) /* * Save and reset save_pending after enabling signals. This * way, signals_pending won't be changed while we're reading it. - */ - signals_enabled = 1; - - /* + * * Setting signals_enabled and reading signals_pending must - * happen in this order. + * happen in this order, so have the barrier here. */ barrier(); @@ -280,10 +279,13 @@ void unblock_signals(void) /* * We have pending interrupts, so disable signals, as the * handlers expect them off when they are called. They will - * be enabled again above. + * be enabled again above. We need to trace this, as we're + * expected to be enabling interrupts already, but any more + * tracing that happens inside the handlers we call for the + * pending signals will mess up the tracing state. */ - signals_enabled = 0; + um_trace_signals_off(); /* * Deal with SIGIO first because the alarm handler might @@ -306,6 +308,9 @@ void unblock_signals(void) if (!(signals_pending & SIGIO_MASK) && (signals_active & SIGALRM_MASK)) return; + /* Re-enable signals and trace that we're doing so. */ + um_trace_signals_on(); + signals_enabled = 1; } } @@ -328,6 +333,21 @@ int set_signals(int enable) return ret; } +int set_signals_trace(int enable) +{ + int ret; + if (signals_enabled == enable) + return enable; + + ret = signals_enabled; + if (enable) + unblock_signals_trace(); + else + block_signals_trace(); + + return ret; +} + int os_is_signal_stack(void) { stack_t ss; diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c index df4a985716eb..095bff707bb3 100644 --- a/arch/um/os-Linux/skas/process.c +++ b/arch/um/os-Linux/skas/process.c @@ -425,9 +425,9 @@ void userspace(struct uml_pt_regs *regs, unsigned long *aux_fp_regs) case SIGBUS: case SIGFPE: case SIGWINCH: - block_signals(); + block_signals_trace(); (*sig_info[sig])(sig, (struct siginfo *)&si, regs); - unblock_signals(); + unblock_signals_trace(); break; default: printk(UM_KERN_ERR "userspace - child stopped " @@ -625,10 +625,10 @@ void initial_thread_cb_skas(void (*proc)(void *), void *arg) cb_arg = arg; cb_back = &here; - block_signals(); + block_signals_trace(); if (UML_SETJMP(&here) == 0) UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK); - unblock_signals(); + unblock_signals_trace(); cb_proc = NULL; cb_arg = NULL; @@ -637,13 +637,13 @@ void initial_thread_cb_skas(void (*proc)(void *), void *arg) void halt_skas(void) { - block_signals(); + block_signals_trace(); UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT); } void reboot_skas(void) { - block_signals(); + block_signals_trace(); UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT); }