From c1a493d4eea7425002d81ce0b412e71ef34fe80b Mon Sep 17 00:00:00 2001
From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Date: Mon, 9 May 2022 16:51:43 +0300
Subject: drm/xen: Add missing VM_DONTEXPAND flag in mmap callback
Git-commit: ca6969013d13282b42cb5edcc13db731a08e0ad8
Patch-mainline: v5.19-rc4
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
With Xen PV Display driver in use the "expected" VM_DONTEXPAND flag
is not set (neither explicitly nor implicitly), so the driver hits
the code path in drm_gem_mmap_obj() which triggers the WARNING.
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Reviewed-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Link: https://lore.kernel.org/r/1652104303-5098-1-git-send-email-olekstysh@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c
index 5a5bf4e5b717..e31554d7139f 100644
--- a/drivers/gpu/drm/xen/xen_drm_front_gem.c
+++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c
@@ -71,7 +71,7 @@ static int xen_drm_front_gem_object_mmap(struct drm_gem_object *gem_obj,
* the whole buffer.
*/
vma->vm_flags &= ~VM_PFNMAP;
- vma->vm_flags |= VM_MIXEDMAP;
+ vma->vm_flags |= VM_MIXEDMAP | VM_DONTEXPAND;
vma->vm_pgoff = 0;
/*
--
2.38.1