The patch below does not apply to the 4.19-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 14dee058610446aa464254fc5c8e88c7535195e0 Mon Sep 17 00:00:00 2001

From: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com Date: Thu, 13 Aug 2020 09:21:10 +0300 Subject: [PATCH] drm/xen-front: Fix misused IS_ERR_OR_NULL checks

The patch c575b7eeb89f: "drm/xen-front: Add support for Xen PV display frontend" from Apr 3, 2018, leads to the following static checker warning:

drivers/gpu/drm/xen/xen_drm_front_gem.c:140 xen_drm_front_gem_create() warn: passing zero to 'ERR_CAST'

drivers/gpu/drm/xen/xen_drm_front_gem.c 133 struct drm_gem_object *xen_drm_front_gem_create(struct drm_device *dev, 134 size_t size) 135 { 136 struct xen_gem_object *xen_obj; 137 138 xen_obj = gem_create(dev, size); 139 if (IS_ERR_OR_NULL(xen_obj)) 140 return ERR_CAST(xen_obj);

Fix this and the rest of misused places with IS_ERR_OR_NULL in the driver.

Fixes: c575b7eeb89f: "drm/xen-front: Add support for Xen PV display frontend"

Signed-off-by: Oleksandr Andrushchenko oleksandr_andrushchenko@epam.com Reported-by: Dan Carpenter dan.carpenter@oracle.com Reviewed-by: Dan Carpenter dan.carpenter@oracle.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200813062113.11030-3-andr2000@gmail.com Signed-off-by: Juergen Gross jgross@suse.com

diff --git a/drivers/gpu/drm/xen/xen_drm_front.c b/drivers/gpu/drm/xen/xen_drm_front.c index 1fd458e877ca..51818e76facd 100644 --- a/drivers/gpu/drm/xen/xen_drm_front.c +++ b/drivers/gpu/drm/xen/xen_drm_front.c @@ -400,8 +400,8 @@ static int xen_drm_drv_dumb_create(struct drm_file *filp, args->size = args->pitch * args->height;

obj = xen_drm_front_gem_create(dev, args->size); - if (IS_ERR_OR_NULL(obj)) { - ret = PTR_ERR_OR_ZERO(obj); + if (IS_ERR(obj)) { + ret = PTR_ERR(obj); goto fail; }

diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c index f0b85e094111..4ec8a49241e1 100644 --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c @@ -83,7 +83,7 @@ static struct xen_gem_object *gem_create(struct drm_device *dev, size_t size)

size = round_up(size, PAGE_SIZE); xen_obj = gem_create_obj(dev, size); - if (IS_ERR_OR_NULL(xen_obj)) + if (IS_ERR(xen_obj)) return xen_obj;

if (drm_info->front_info->cfg.be_alloc) { @@ -117,7 +117,7 @@ static struct xen_gem_object *gem_create(struct drm_device *dev, size_t size) */ xen_obj->num_pages = DIV_ROUND_UP(size, PAGE_SIZE); xen_obj->pages = drm_gem_get_pages(&xen_obj->base); - if (IS_ERR_OR_NULL(xen_obj->pages)) { + if (IS_ERR(xen_obj->pages)) { ret = PTR_ERR(xen_obj->pages); xen_obj->pages = NULL; goto fail; @@ -136,7 +136,7 @@ struct drm_gem_object *xen_drm_front_gem_create(struct drm_device *dev, struct xen_gem_object *xen_obj;

xen_obj = gem_create(dev, size); - if (IS_ERR_OR_NULL(xen_obj)) + if (IS_ERR(xen_obj)) return ERR_CAST(xen_obj);

return &xen_obj->base; @@ -194,7 +194,7 @@ xen_drm_front_gem_import_sg_table(struct drm_device *dev,

size = attach->dmabuf->size; xen_obj = gem_create_obj(dev, size); - if (IS_ERR_OR_NULL(xen_obj)) + if (IS_ERR(xen_obj)) return ERR_CAST(xen_obj);

ret = gem_alloc_pages_array(xen_obj, size); diff --git a/drivers/gpu/drm/xen/xen_drm_front_kms.c b/drivers/gpu/drm/xen/xen_drm_front_kms.c index 78096bbcd226..ef11b1e4de39 100644 --- a/drivers/gpu/drm/xen/xen_drm_front_kms.c +++ b/drivers/gpu/drm/xen/xen_drm_front_kms.c @@ -60,7 +60,7 @@ fb_create(struct drm_device *dev, struct drm_file *filp, int ret;

fb = drm_gem_fb_create_with_funcs(dev, filp, mode_cmd, &fb_funcs); - if (IS_ERR_OR_NULL(fb)) + if (IS_ERR(fb)) return fb;

gem_obj = fb->obj[0];