@@ -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
@@ -239,6 +239,7 @@ 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);
@@ -324,4 +325,10 @@ 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
@@ -127,6 +127,8 @@ void new_thread_handler(void)
fn = current->thread.request.u.thread.proc;
arg = current->thread.request.u.thread.arg;
+ um_trace_signals_on();
+
/*
* callback returns only if the kernel thread execs a process
*/
@@ -6,14 +6,40 @@
#include <linux/module.h>
#include <linux/ptrace.h>
#include <linux/sched.h>
+#include <linux/ftrace.h>
#include <asm/siginfo.h>
#include <asm/signal.h>
#include <asm/unistd.h>
#include <frame_kern.h>
#include <kern_util.h>
+#include <os.h>
-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
@@ -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;
@@ -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;
@@ -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 */
@@ -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)
@@ -34,6 +34,8 @@ static void sig_handler_common(int sig, struct siginfo *si, mcontext_t *mc)
struct uml_pt_regs r;
int save_errno = errno;
+ um_trace_signals_off();
+
r.is_user = 0;
if (sig == SIGSEGV) {
/* For segfaults, we want the data from the sigcontext. */
@@ -43,7 +45,7 @@ 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 +78,11 @@ 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 +106,7 @@ 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 +114,7 @@ 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 +255,8 @@ 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 +266,9 @@ 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 +281,13 @@ 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 +310,9 @@ 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 +335,21 @@ 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;
@@ -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);
}