KEYS: Extend TIF_NOTIFY_RESUME to (almost) all architectures [try #6]
Implement TIF_NOTIFY_RESUME for most of those architectures in which isn't yet
available, and, whilst we're at it, have it call the appropriate tracehook.
After this patch, blackfin, m68k* and xtensa still lack support and need
alteration of assembly code to make it work.
Resume notification can then be used (by a later patch) to install a new
session keyring on the parent of a process.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
cc: linux-arch@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/arch/avr32/include/asm/thread_info.h b/arch/avr32/include/asm/thread_info.h
index fc42de5..fd0c5d7 100644
--- a/arch/avr32/include/asm/thread_info.h
+++ b/arch/avr32/include/asm/thread_info.h
@@ -84,6 +84,7 @@
#define TIF_MEMDIE 6
#define TIF_RESTORE_SIGMASK 7 /* restore signal mask in do_signal */
#define TIF_CPU_GOING_TO_SLEEP 8 /* CPU is entering sleep 0 mode */
+#define TIF_NOTIFY_RESUME 9 /* callback before returning to user */
#define TIF_FREEZE 29
#define TIF_DEBUG 30 /* debugging enabled */
#define TIF_USERSPACE 31 /* true if FS sets userspace */
@@ -96,6 +97,7 @@
#define _TIF_MEMDIE (1 << TIF_MEMDIE)
#define _TIF_RESTORE_SIGMASK (1 << TIF_RESTORE_SIGMASK)
#define _TIF_CPU_GOING_TO_SLEEP (1 << TIF_CPU_GOING_TO_SLEEP)
+#define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME)
#define _TIF_FREEZE (1 << TIF_FREEZE)
/* Note: The masks below must never span more than 16 bits! */
@@ -103,13 +105,15 @@
/* work to do on interrupt/exception return */
#define _TIF_WORK_MASK \
((1 << TIF_SIGPENDING) \
+ | _TIF_NOTIFY_RESUME \
| (1 << TIF_NEED_RESCHED) \
| (1 << TIF_POLLING_NRFLAG) \
| (1 << TIF_BREAKPOINT) \
| (1 << TIF_RESTORE_SIGMASK))
/* work to do on any return to userspace */
-#define _TIF_ALLWORK_MASK (_TIF_WORK_MASK | (1 << TIF_SYSCALL_TRACE))
+#define _TIF_ALLWORK_MASK (_TIF_WORK_MASK | (1 << TIF_SYSCALL_TRACE) | \
+ _TIF_NOTIFY_RESUME)
/* work to do on return from debug mode */
#define _TIF_DBGWORK_MASK (_TIF_WORK_MASK & ~(1 << TIF_BREAKPOINT))
diff --git a/arch/avr32/kernel/entry-avr32b.S b/arch/avr32/kernel/entry-avr32b.S
index 009a801..169268c 100644
--- a/arch/avr32/kernel/entry-avr32b.S
+++ b/arch/avr32/kernel/entry-avr32b.S
@@ -281,7 +281,7 @@
ld.w r1, r0[TI_flags]
rjmp 1b
-2: mov r2, _TIF_SIGPENDING | _TIF_RESTORE_SIGMASK
+2: mov r2, _TIF_SIGPENDING | _TIF_RESTORE_SIGMASK | _TIF_NOTIFY_RESUME
tst r1, r2
breq 3f
unmask_interrupts
diff --git a/arch/avr32/kernel/signal.c b/arch/avr32/kernel/signal.c
index 2722756..62d242e 100644
--- a/arch/avr32/kernel/signal.c
+++ b/arch/avr32/kernel/signal.c
@@ -322,4 +322,9 @@
if (ti->flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK))
do_signal(regs, ¤t->blocked, syscall);
+
+ if (ti->flags & _TIF_NOTIFY_RESUME) {
+ clear_thread_flag(TIF_NOTIFY_RESUME);
+ tracehook_notify_resume(regs);
+ }
}