aboutsummaryrefslogtreecommitdiff
path: root/arch/um/os-Linux/start_up.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/um/os-Linux/start_up.c')
-rw-r--r--arch/um/os-Linux/start_up.c28
1 files changed, 17 insertions, 11 deletions
diff --git a/arch/um/os-Linux/start_up.c b/arch/um/os-Linux/start_up.c
index a8b5b9d9c6e..040cc1472bc 100644
--- a/arch/um/os-Linux/start_up.c
+++ b/arch/um/os-Linux/start_up.c
@@ -161,7 +161,7 @@ __uml_setup("nosysemu", nosysemu_cmd_param,
static void __init check_sysemu(void)
{
void *stack;
- int pid, syscall, n, status, count=0;
+ int pid, n, status, count=0;
printk("Checking syscall emulation patch for ptrace...");
sysemu_supported = 0;
@@ -192,6 +192,12 @@ static void __init check_sysemu(void)
printk("Checking advanced syscall emulation patch for ptrace...");
pid = start_ptraced_child(&stack);
+
+ if(ptrace(PTRACE_OLDSETOPTIONS, pid, 0,
+ (void *) PTRACE_O_TRACESYSGOOD) < 0)
+ panic("check_ptrace: PTRACE_OLDSETOPTIONS failed, errno = %d",
+ errno);
+
while(1){
count++;
if(ptrace(PTRACE_SYSEMU_SINGLESTEP, pid, 0, 0) < 0)
@@ -199,15 +205,10 @@ static void __init check_sysemu(void)
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if(n < 0)
panic("check_ptrace : wait failed, errno = %d", errno);
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP))
- panic("check_ptrace : expected (SIGTRAP|SYSCALL_TRAP), "
- "got status = %d", status);
-
- syscall = ptrace(PTRACE_PEEKUSR, pid, PT_SYSCALL_NR_OFFSET,
- 0);
- if(syscall == __NR_getpid){
+ if(WIFSTOPPED(status) && (WSTOPSIG(status) == (SIGTRAP|0x80))){
if (!count)
- panic("check_ptrace : SYSEMU_SINGLESTEP doesn't singlestep");
+ panic("check_ptrace : SYSEMU_SINGLESTEP "
+ "doesn't singlestep");
n = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_RET_OFFSET,
os_getpid());
if(n < 0)
@@ -215,6 +216,11 @@ static void __init check_sysemu(void)
"call return, errno = %d", errno);
break;
}
+ else if(WIFSTOPPED(status) && (WSTOPSIG(status) == SIGTRAP))
+ count++;
+ else
+ panic("check_ptrace : expected SIGTRAP or "
+ "(SIGTRAP|0x80), got status = %d", status);
}
if (stop_ptraced_child(pid, stack, 0, 0) < 0)
goto fail_stopped;
@@ -250,8 +256,8 @@ static void __init check_ptrace(void)
CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
if(n < 0)
panic("check_ptrace : wait failed, errno = %d", errno);
- if(!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGTRAP + 0x80))
- panic("check_ptrace : expected SIGTRAP + 0x80, "
+ if(!WIFSTOPPED(status) || (WSTOPSIG(status) != (SIGTRAP|0x80)))
+ panic("check_ptrace : expected (SIGTRAP|0x80), "
"got status = %d", status);
syscall = ptrace(PTRACE_PEEKUSR, pid, PT_SYSCALL_NR_OFFSET,