From: Jia-Ju Bai Date: Mon, 9 Apr 2018 15:03:53 +0000 (+0800) Subject: xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_init_device X-Git-Tag: v4.19~1057^2~7 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=bb52e3169cb7dd5a9deea39b94342fce36235a5b;p=platform%2Fkernel%2Flinux-rpi.git xen: xen-pciback: Replace GFP_ATOMIC with GFP_KERNEL in pcistub_init_device pcistub_init_device() is never called in atomic context. The call chain ending up at pcistub_init_device() is: [1] pcistub_init_device() <- pcistub_seize() <- pcistub_probe() [2] pcistub_init_device() <- pcistub_init_devices_late() <- xen_pcibk_init() pcistub_probe() is only set as ".probe" in struct pci_driver. xen_pcibk_init() is is only set as a parameter of module_init(). These functions are not called in atomic context. Despite never getting called from atomic context, pcistub_init_device() calls kzalloc() with GFP_ATOMIC, which does not sleep for allocation. GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL, which can sleep and improve the possibility of sucessful allocation. This is found by a static analysis tool named DCNS written by myself. And I also manually check it. Signed-off-by: Jia-Ju Bai Reviewed-by: Boris Ostrovsky Signed-off-by: Boris Ostrovsky --- diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index 95e6ddd..b36fa76 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -364,7 +364,7 @@ static int pcistub_init_device(struct pci_dev *dev) * here and then to call kfree(pci_get_drvdata(psdev->dev)). */ dev_data = kzalloc(sizeof(*dev_data) + strlen(DRV_NAME "[]") - + strlen(pci_name(dev)) + 1, GFP_ATOMIC); + + strlen(pci_name(dev)) + 1, GFP_KERNEL); if (!dev_data) { err = -ENOMEM; goto out;