powerpc: Add TIF_NOTIFY_RESUME support for tracehook
This adds TIF_NOTIFY_RESUME support for powerpc. When set,
we call tracehook_notify_resume() on the way to user mode.
This overloads do_signal() to do the work, but changes its
arguments to it has the TIF_* bits handy in a register and
drops the useless first argument that was always zero.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index e6fca6a..1cbbf70 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -1060,8 +1060,8 @@
SAVE_NVGPRS(r1)
rlwinm r3,r3,0,0,30
stw r3,_TRAP(r1)
-2: li r3,0
- addi r4,r1,STACK_FRAME_OVERHEAD
+2: addi r3,r1,STACK_FRAME_OVERHEAD
+ mr r4,r9
bl do_signal
REST_NVGPRS(r1)
b recheck
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 79c089e..2d802e9 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -643,8 +643,7 @@
b .ret_from_except_lite
1: bl .save_nvgprs
- li r3,0
- addi r4,r1,STACK_FRAME_OVERHEAD
+ addi r3,r1,STACK_FRAME_OVERHEAD
bl .do_signal
b .ret_from_except
diff --git a/arch/powerpc/kernel/signal.c b/arch/powerpc/kernel/signal.c
index e74aa0e..a54405e 100644
--- a/arch/powerpc/kernel/signal.c
+++ b/arch/powerpc/kernel/signal.c
@@ -112,7 +112,7 @@
}
}
-int do_signal(sigset_t *oldset, struct pt_regs *regs)
+static int do_signal_pending(sigset_t *oldset, struct pt_regs *regs)
{
siginfo_t info;
int signr;
@@ -188,6 +188,17 @@
return ret;
}
+void do_signal(struct pt_regs *regs, unsigned long thread_info_flags)
+{
+ if (thread_info_flags & _TIF_SIGPENDING)
+ do_signal_pending(NULL, regs);
+
+ if (thread_info_flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
+}
+
long sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
unsigned long r5, unsigned long r6, unsigned long r7,
unsigned long r8, struct pt_regs *regs)
diff --git a/include/asm-powerpc/signal.h b/include/asm-powerpc/signal.h
index a8c7bab..a7360cd 100644
--- a/include/asm-powerpc/signal.h
+++ b/include/asm-powerpc/signal.h
@@ -122,8 +122,7 @@
#ifdef __KERNEL__
struct pt_regs;
-extern int do_signal(sigset_t *oldset, struct pt_regs *regs);
-extern int do_signal32(sigset_t *oldset, struct pt_regs *regs);
+extern void do_signal(struct pt_regs *regs, unsigned long thread_info_flags);
#define ptrace_signal_deliver(regs, cookie) do { } while (0)
#endif /* __KERNEL__ */
diff --git a/include/asm-powerpc/thread_info.h b/include/asm-powerpc/thread_info.h
index a9db562..9665a26 100644
--- a/include/asm-powerpc/thread_info.h
+++ b/include/asm-powerpc/thread_info.h
@@ -108,6 +108,7 @@
#define TIF_SECCOMP 10 /* secure computing */
#define TIF_RESTOREALL 11 /* Restore all regs (implies NOERROR) */
#define TIF_NOERROR 12 /* Force successful syscall return */
+#define TIF_NOTIFY_RESUME 13 /* callback before returning to user */
#define TIF_FREEZE 14 /* Freezing for suspend */
#define TIF_RUNLATCH 15 /* Is the runlatch enabled? */
#define TIF_ABI_PENDING 16 /* 32/64 bit switch needed */
@@ -125,12 +126,14 @@
#define _TIF_SECCOMP (1<<TIF_SECCOMP)
#define _TIF_RESTOREALL (1<<TIF_RESTOREALL)
#define _TIF_NOERROR (1<<TIF_NOERROR)
+#define _TIF_NOTIFY_RESUME (1<<TIF_NOTIFY_RESUME)
#define _TIF_FREEZE (1<<TIF_FREEZE)
#define _TIF_RUNLATCH (1<<TIF_RUNLATCH)
#define _TIF_ABI_PENDING (1<<TIF_ABI_PENDING)
#define _TIF_SYSCALL_T_OR_A (_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SECCOMP)
-#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED)
+#define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \
+ _TIF_NOTIFY_RESUME)
#define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR)
/* Bits in local_flags */
