From: Jon Derrick <jonathan.derrick@intel.com>
Date: Sat, 16 Mar 2019 00:05:17 +0000 (-0600)
Subject: drm/nouveau/bar/gf100: ensure BAR is mapped
X-Git-Tag: v4.19.98~14
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3579293f6bace77815ca2ebe47d98ad73b469c95;p=thirdparty%2Fkernel%2Fstable.git

drm/nouveau/bar/gf100: ensure BAR is mapped

commit 12e08beb32d64b6070b718630490db83dd321c8c upstream.

If the BAR is zero size, it indicates it was never successfully mapped.
Ensure that the BAR is valid during initialization before attempting to
use it.

Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Sushma Kalakota <sushmax.kalakota@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gf100.c b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gf100.c
index a3ba7f50198be..a3dcb09a40ee3 100644
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gf100.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/bar/gf100.c
@@ -94,6 +94,8 @@ gf100_bar_oneinit_bar(struct gf100_bar *bar, struct gf100_barN *bar_vm,
 		return ret;
 
 	bar_len = device->func->resource_size(device, bar_nr);
+	if (!bar_len)
+		return -ENOMEM;
 	if (bar_nr == 3 && bar->bar2_halve)
 		bar_len >>= 1;