[PATCH 3.12 069/116] vgaarb: fix signal handling in vga_get()

From: Jiri Slaby
Date: Fri Mar 04 2016 - 04:04:48 EST


From: "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx>

3.12-stable review patch. If anyone has any objections, please let me know.

===============

commit 9f5bd30818c42c6c36a51f93b4df75a2ea2bd85e upstream.

There are few defects in vga_get() related to signal hadning:

- we shouldn't check for pending signals for TASK_UNINTERRUPTIBLE
case;

- if we found pending signal we must remove ourself from wait queue
and change task state back to running;

- -ERESTARTSYS is more appropriate, I guess.

Signed-off-by: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx>
Reviewed-by: David Herrmann <dh.herrmann@xxxxxxxxx>
Signed-off-by: Dave Airlie <airlied@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/gpu/vga/vgaarb.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/vga/vgaarb.c b/drivers/gpu/vga/vgaarb.c
index af0259708358..bbb554d586d4 100644
--- a/drivers/gpu/vga/vgaarb.c
+++ b/drivers/gpu/vga/vgaarb.c
@@ -392,8 +392,10 @@ int vga_get(struct pci_dev *pdev, unsigned int rsrc, int interruptible)
set_current_state(interruptible ?
TASK_INTERRUPTIBLE :
TASK_UNINTERRUPTIBLE);
- if (signal_pending(current)) {
- rc = -EINTR;
+ if (interruptible && signal_pending(current)) {
+ __set_current_state(TASK_RUNNING);
+ remove_wait_queue(&vga_wait_queue, &wait);
+ rc = -ERESTARTSYS;
break;
}
schedule();
--
2.7.2