The patch below does not apply to the 4.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From c37406e05d1e541df40b8b81c4bd40753fcaf414 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Christian=20K=C3=B6nig?= ckoenig.leichtzumerken@gmail.com Date: Mon, 26 Feb 2018 14:51:13 -0600 Subject: [PATCH] PCI: Allow release of resources that were never assigned MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

It is entirely possible that the BIOS wasn't able to assign resources to a device. In this case don't crash in pci_release_resource() when we try to resize the resource.

Fixes: 8bb705e3e79d ("PCI: Add pci_resize_resource() for resizing BARs") Signed-off-by: Christian König christian.koenig@amd.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com CC: stable@vger.kernel.org # v4.15+

diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c index 369d48d6c6f1..365447240d95 100644 --- a/drivers/pci/setup-res.c +++ b/drivers/pci/setup-res.c @@ -401,6 +401,10 @@ void pci_release_resource(struct pci_dev *dev, int resno) struct resource *res = dev->resource + resno;

pci_info(dev, "BAR %d: releasing %pR\n", resno, res); + + if (!res->parent) + return; + release_resource(res); res->end = resource_size(res) - 1; res->start = 0;