4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Mikulas Patocka <mpatocka@xxxxxxxxxx>
commit 080fb5240bdcabed7387b814139c3ea172d59fc5 upstream.
Allocations larger than PAGE_ALLOC_COSTLY_ORDER are unreliable and they
may fail anytime. This patch fixes the udlfb driver so that when a large
alloactions fails, it tries to do multiple smaller allocations.
Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/video/fbdev/udlfb.c | 26 +++++++++++++++++---------
1 file changed, 17 insertions(+), 9 deletions(-)
--- a/drivers/video/fbdev/udlfb.c
+++ b/drivers/video/fbdev/udlfb.c
@@ -1843,17 +1843,22 @@ static void dlfb_free_urb_list(struct dl
static int dlfb_alloc_urb_list(struct dlfb_data *dlfb, int count, size_t size)
{
- int i = 0;
struct urb *urb;
struct urb_node *unode;
char *buf;
+ size_t wanted_size = count * size;
spin_lock_init(&dlfb->urbs.lock);
+retry:
dlfb->urbs.size = size;
INIT_LIST_HEAD(&dlfb->urbs.list);
- while (i < count) {
+ sema_init(&dlfb->urbs.limit_sem, 0);
+ dlfb->urbs.count = 0;
+ dlfb->urbs.available = 0;
+
+ while (dlfb->urbs.count * size < wanted_size) {
unode = kzalloc(sizeof(*unode), GFP_KERNEL);
if (!unode)
break;
@@ -1866,11 +1871,16 @@ static int dlfb_alloc_urb_list(struct dl
}
unode->urb = urb;
- buf = usb_alloc_coherent(dlfb->udev, MAX_TRANSFER, GFP_KERNEL,
+ buf = usb_alloc_coherent(dlfb->udev, size, GFP_KERNEL,
&urb->transfer_dma);
if (!buf) {
kfree(unode);
usb_free_urb(urb);
+ if (size > PAGE_SIZE) {
+ size /= 2;
+ dlfb_free_urb_list(dlfb);
+ goto retry;
+ }
break;
}
@@ -1881,14 +1891,12 @@ static int dlfb_alloc_urb_list(struct dl
list_add_tail(&unode->entry, &dlfb->urbs.list);
- i++;
+ up(&dlfb->urbs.limit_sem);
+ dlfb->urbs.count++;
+ dlfb->urbs.available++;
}
- sema_init(&dlfb->urbs.limit_sem, i);
- dlfb->urbs.count = i;
- dlfb->urbs.available = i;
-
- return i;
+ return dlfb->urbs.count;
}
static struct urb *dlfb_get_urb(struct dlfb_data *dlfb)
