From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:46920 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728173AbeIHCIP (ORCPT ); Fri, 7 Sep 2018 22:08:15 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mikulas Patocka , Bartlomiej Zolnierkiewicz Subject: [PATCH 4.18 126/145] udlfb: handle allocation failure Date: Fri, 7 Sep 2018 23:09:52 +0200 Message-Id: <20180907210913.301071343@linuxfoundation.org> In-Reply-To: <20180907210903.617721278@linuxfoundation.org> References: <20180907210903.617721278@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mikulas Patocka 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 Cc: stable@vger.kernel.org Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Greg Kroah-Hartman --- 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)