char/agp: Disable frontend without CONFIG_DRM_LEGACY

It's probably full of bugs ready for exploiting by userspace. And
there's not going to be any userspace for this without any of the drm
legacy drivers enabled too. So just couple it together.

Note that the frontend is only the /dev/agp ioctl interface, which per
Adam is only used by the i810 userspace drivers. All other drivers go
through the drm bufmap agp handling abstraction apparently.

v2: Augment commit message a bit from m-l feedback.

Acked-by: Adam Jackson <ajax@redhat.com>
Acked-by: Christian König <christian.koenig@amd.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Adam Jackson <ajax@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201117214029.591896-1-daniel.vetter@ffwll.ch
This commit is contained in:
Daniel Vetter 2020-11-17 22:40:29 +01:00
parent 58a74c6f1d
commit f9f92e7c58
2 changed files with 10 additions and 1 deletions

View File

@ -1,7 +1,11 @@
# SPDX-License-Identifier: GPL-2.0
agpgart-y := backend.o frontend.o generic.o isoch.o
agpgart-y := backend.o generic.o isoch.o
ifeq ($(CONFIG_DRM_LEGACY),y)
agpgart-$(CONFIG_COMPAT) += compat_ioctl.o
agpgart-y += frontend.o
endif
obj-$(CONFIG_AGP) += agpgart.o
obj-$(CONFIG_AGP_ALI) += ali-agp.o

View File

@ -186,8 +186,13 @@ int agp_add_bridge(struct agp_bridge_data *bridge);
void agp_remove_bridge(struct agp_bridge_data *bridge);
/* Frontend routines. */
#if IS_ENABLED(CONFIG_DRM_LEGACY)
int agp_frontend_initialize(void);
void agp_frontend_cleanup(void);
#else
static inline int agp_frontend_initialize(void) { return 0; }
static inline void agp_frontend_cleanup(void) {}
#endif
/* Generic routines. */
void agp_generic_enable(struct agp_bridge_data *bridge, u32 mode);