Commit ea97e44f authored by Venkata Sandeep Dhanalakota's avatar Venkata Sandeep Dhanalakota Committed by John Harrison
Browse files

drm/i915: Do not define vma on stack 



Defining vma on stack can cause stack overflow, if
vma gets populated with new fields.

v2:
 (Daniel Vetter)
  - Add kerneldoc for new field

Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: default avatarVenkata Sandeep Dhanalakota <venkata.s.dhanalakota@intel.com>
Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Reviewed-by: default avatarMatthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210916162819.27848-2-matthew.brost@intel.com
parent 53718bff

drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c

+9 −9
Original line number Diff line number Diff line
@@ -413,20 +413,20 @@ static void uc_fw_bind_ggtt(struct intel_uc_fw *uc_fw) 
{

	struct drm_i915_gem_object *obj = uc_fw->obj;

	struct i915_ggtt *ggtt = __uc_fw_to_gt(uc_fw)->ggtt;

	struct i915_vma dummy = {

		.node.start = uc_fw_ggtt_offset(uc_fw),

		.node.size = obj->base.size,

		.pages = obj->mm.pages,

		.vm = &ggtt->vm,

	};

	struct i915_vma *dummy = &uc_fw->dummy;



	dummy->node.start = uc_fw_ggtt_offset(uc_fw);

	dummy->node.size = obj->base.size;

	dummy->pages = obj->mm.pages;

	dummy->vm = &ggtt->vm;



	GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));

	GEM_BUG_ON(dummy.node.size > ggtt->uc_fw.size);

	GEM_BUG_ON(dummy->node.size > ggtt->uc_fw.size);



	/* uc_fw->obj cache domains were not controlled across suspend */

	drm_clflush_sg(dummy.pages);

	drm_clflush_sg(dummy->pages);



	ggtt->vm.insert_entries(&ggtt->vm, &dummy, I915_CACHE_NONE, 0);

	ggtt->vm.insert_entries(&ggtt->vm, dummy, I915_CACHE_NONE, 0);

}



static void uc_fw_unbind_ggtt(struct intel_uc_fw *uc_fw)

drivers/gpu/drm/i915/gt/uc/intel_uc_fw.h

+9 −0
Original line number Diff line number Diff line
@@ -10,6 +10,7 @@ 
#include "intel_uc_fw_abi.h"

#include "intel_device_info.h"

#include "i915_gem.h"

#include "i915_vma.h"



struct drm_printer;

struct drm_i915_private;
@@ -75,6 +76,14 @@ struct intel_uc_fw { 
	bool user_overridden;

	size_t size;

	struct drm_i915_gem_object *obj;

	/**

	 * @dummy: A vma used in binding the uc fw to ggtt. We can't define this

	 * vma on the stack as it can lead to a stack overflow, so we define it

	 * here. Safe to have 1 copy per uc fw because the binding is single

	 * threaded as it done during driver load (inherently single threaded)

	 * or during a GT reset (mutex guarantees single threaded).

	 */

	struct i915_vma dummy;



	/*

	 * The firmware build process will generate a version header file with major and