Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull rseq fixes from Thomas Gleixer:
 "A pile of rseq related fixups:

   - Prevent infinite recursion when delivering SIGSEGV

   - Remove the abort of rseq critical section on fork() as syscalls
     inside rseq critical sections are explicitely forbidden. So no
     point in doing the abort on the child.

   - Align the rseq structure on 32 bytes in the ARM selftest code.

   - Fix file permissions of the test script"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rseq: Avoid infinite recursion when delivering SIGSEGV
  rseq/cleanup: Do not abort rseq c.s. in child on fork()
  rseq/selftests/arm: Align 'struct rseq_cs' on 32 bytes
  rseq/selftests: Make run_param_test.sh executable

1 files changed, 12 insertions, 11 deletions

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 87bf02d93a27..9256118bd40c 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1799,20 +1799,22 @@ static inline void rseq_set_notify_resume(struct task_struct *t)
                 set_tsk_thread_flag(t, TIF_NOTIFY_RESUME);
 }
 
-void __rseq_handle_notify_resume(struct pt_regs *regs);
+void __rseq_handle_notify_resume(struct ksignal *sig, struct pt_regs *regs);
 
-static inline void rseq_handle_notify_resume(struct pt_regs *regs)
+static inline void rseq_handle_notify_resume(struct ksignal *ksig,
+                                             struct pt_regs *regs)
 {
         if (current->rseq)
-                __rseq_handle_notify_resume(regs);
+                __rseq_handle_notify_resume(ksig, regs);
 }
 
-static inline void rseq_signal_deliver(struct pt_regs *regs)
+static inline void rseq_signal_deliver(struct ksignal *ksig,
+                                       struct pt_regs *regs)
 {
         preempt_disable();
         __set_bit(RSEQ_EVENT_SIGNAL_BIT, &current->rseq_event_mask);
         preempt_enable();
-        rseq_handle_notify_resume(regs);
+        rseq_handle_notify_resume(ksig, regs);
 }
 
 /* rseq_preempt() requires preemption to be disabled. */
@@ -1831,9 +1833,7 @@ static inline void rseq_migrate(struct task_struct *t)
 
 /*
  * If parent process has a registered restartable sequences area, the
- * child inherits. Only applies when forking a process, not a thread. In
- * case a parent fork() in the middle of a restartable sequence, set the
- * resume notifier to force the child to retry.
+ * child inherits. Only applies when forking a process, not a thread.
  */
 static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
 {
@@ -1847,7 +1847,6 @@ static inline void rseq_fork(struct task_struct *t, unsigned long clone_flags)
                 t->rseq_len = current->rseq_len;
                 t->rseq_sig = current->rseq_sig;
                 t->rseq_event_mask = current->rseq_event_mask;
-                rseq_preempt(t);
         }
 }
 
@@ -1864,10 +1863,12 @@ static inline void rseq_execve(struct task_struct *t)
 static inline void rseq_set_notify_resume(struct task_struct *t)
 {
 }
-static inline void rseq_handle_notify_resume(struct pt_regs *regs)
+static inline void rseq_handle_notify_resume(struct ksignal *ksig,
+                                             struct pt_regs *regs)
 {
 }
-static inline void rseq_signal_deliver(struct pt_regs *regs)
+static inline void rseq_signal_deliver(struct ksignal *ksig,
+                                       struct pt_regs *regs)
 {
 }
 static inline void rseq_preempt(struct task_struct *t)