[IA64] fix interrupt masking for pending works on kernel leave
[Bug-fix for "[BUG?][2.6.25-mm1] sleeping during IRQ disabled"]
This patch does:
- enable interrupts before calling schedule() as same as others, ex. x86
- enable interrupts during ia64_do_signal() and ia64_sync_krbs()
- do_notify_resume_user() is still called with interrupts disabled, since
we can take short path of fsys_mode if-statement quickly.
- pfm_handle_work() is also called with interrupts disabled, since
it can deal interrupt mask within itself.
- fix/add some comments/notes
Reported-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S
index e49ad8c..ef6b031 100644
--- a/arch/ia64/kernel/entry.S
+++ b/arch/ia64/kernel/entry.S
@@ -1156,6 +1156,9 @@
* r31 = current->thread_info->flags
* On exit:
* p6 = TRUE if work-pending-check needs to be redone
+ *
+ * Interrupts are disabled on entry, reenabled depend on work, and
+ * disabled on exit.
*/
.work_pending_syscall:
add r2=-8,r2
@@ -1170,8 +1173,8 @@
(pKStk) dep r21=-1,r0,PREEMPT_ACTIVE_BIT,1
;;
(pKStk) st4 [r20]=r21
- ssm psr.i // enable interrupts
#endif
+ ssm psr.i // enable interrupts
br.call.spnt.many rp=schedule
.ret9: cmp.eq p6,p0=r0,r0 // p6 <- 1
rsm psr.i // disable interrupts
@@ -1234,9 +1237,12 @@
END(ia64_invoke_schedule_tail)
/*
- * Setup stack and call do_notify_resume_user(). Note that pSys and pNonSys need to
- * be set up by the caller. We declare 8 input registers so the system call
- * args get preserved, in case we need to restart a system call.
+ * Setup stack and call do_notify_resume_user(), keeping interrupts
+ * disabled.
+ *
+ * Note that pSys and pNonSys need to be set up by the caller.
+ * We declare 8 input registers so the system call args get preserved,
+ * in case we need to restart a system call.
*/
ENTRY(notify_resume_user)
.prologue ASM_UNW_PRLG_RP|ASM_UNW_PRLG_PFS, ASM_UNW_PRLG_GRSAVE(8)
