[PATCH 1/5] drm/i915/gem: Typecheck page lookups
Gwan-gyeong Mun
gwan-gyeong.mun at intel.com
Thu Jun 2 11:26:15 UTC 2022
From: Chris Wilson <chris at chris-wilson.co.uk>
We need to check that we avoid integer overflows when looking up a page,
and so fix all the instances where we have mistakenly used a plain
integer instead of a more suitable long. Be pedantic and add integer
typechecking to the lookup so that we can be sure that we are safe.
And it also uses pgoff_t as our page lookups must remain compatible with
the page cache, pgoff_t is currently exactly unsigned long.
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun at intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin at linux.intel.com>
Cc: Matthew Auld <matthew.auld at intel.com>
Cc: Thomas Hellström <thomas.hellstrom at linux.intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_object.c | 7 +-
drivers/gpu/drm/i915/gem/i915_gem_object.h | 67 ++++++++++++++-----
drivers/gpu/drm/i915/gem/i915_gem_pages.c | 25 ++++---
drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 2 +-
.../drm/i915/gem/selftests/i915_gem_context.c | 12 ++--
.../drm/i915/gem/selftests/i915_gem_mman.c | 8 +--
.../drm/i915/gem/selftests/i915_gem_object.c | 8 +--
drivers/gpu/drm/i915/i915_gem.c | 18 +++--
drivers/gpu/drm/i915/i915_utils.h | 6 ++
drivers/gpu/drm/i915/i915_vma.c | 8 +--
10 files changed, 106 insertions(+), 55 deletions(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c b/drivers/gpu/drm/i915/gem/i915_gem_object.c
index 06b1b188ce5a..a5af74f78d57 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
@@ -421,10 +421,11 @@ void __i915_gem_object_invalidate_frontbuffer(struct drm_i915_gem_object *obj,
static void
i915_gem_object_read_from_page_kmap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
{
+ pgoff_t idx = offset >> PAGE_SHIFT;
void *src_map;
void *src_ptr;
- src_map = kmap_atomic(i915_gem_object_get_page(obj, offset >> PAGE_SHIFT));
+ src_map = kmap_atomic(i915_gem_object_get_page(obj, idx));
src_ptr = src_map + offset_in_page(offset);
if (!(obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ))
@@ -437,9 +438,10 @@ i915_gem_object_read_from_page_kmap(struct drm_i915_gem_object *obj, u64 offset,
static void
i915_gem_object_read_from_page_iomap(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
{
+ pgoff_t idx = offset >> PAGE_SHIFT;
+ dma_addr_t dma = i915_gem_object_get_dma_address(obj, idx);
void __iomem *src_map;
void __iomem *src_ptr;
- dma_addr_t dma = i915_gem_object_get_dma_address(obj, offset >> PAGE_SHIFT);
src_map = io_mapping_map_wc(&obj->mm.region->iomap,
dma - obj->mm.region->region.start,
@@ -468,6 +470,7 @@ i915_gem_object_read_from_page_iomap(struct drm_i915_gem_object *obj, u64 offset
*/
int i915_gem_object_read_from_page(struct drm_i915_gem_object *obj, u64 offset, void *dst, int size)
{
+ GEM_BUG_ON(overflows_type(offset >> PAGE_SHIFT, pgoff_t));
GEM_BUG_ON(offset >= obj->base.size);
GEM_BUG_ON(offset_in_page(offset) > PAGE_SIZE - size);
GEM_BUG_ON(!i915_gem_object_has_pinned_pages(obj));
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.h b/drivers/gpu/drm/i915/gem/i915_gem_object.h
index e11d82a9f7c3..22c4ba0cd106 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.h
@@ -27,8 +27,10 @@ enum intel_region_id;
* spot such a local variable, please consider fixing!
*
* Aside from our own locals (for which we have no excuse!):
- * - sg_table embeds unsigned int for num_pages
- * - get_user_pages*() mixed ints with longs
+ * - sg_table embeds unsigned int for nents
+ *
+ * We can check for invalidly typed locals with typecheck(), see for example
+ * i915_gem_object_get_sg().
*/
#define GEM_CHECK_SIZE_OVERFLOW(sz) \
GEM_WARN_ON((sz) >> PAGE_SHIFT > INT_MAX)
@@ -366,41 +368,70 @@ int i915_gem_object_set_tiling(struct drm_i915_gem_object *obj,
struct scatterlist *
__i915_gem_object_get_sg(struct drm_i915_gem_object *obj,
struct i915_gem_object_page_iter *iter,
- unsigned int n,
- unsigned int *offset, bool dma);
+ pgoff_t n,
+ unsigned int *offset);
+
+#define __i915_gem_object_get_sg(obj, it, n, offset) ({ \
+ exactly_pgoff_t(n); \
+ (__i915_gem_object_get_sg)(obj, it, n, offset); \
+})
static inline struct scatterlist *
-i915_gem_object_get_sg(struct drm_i915_gem_object *obj,
- unsigned int n,
+i915_gem_object_get_sg(struct drm_i915_gem_object *obj, pgoff_t n,
unsigned int *offset)
{
- return __i915_gem_object_get_sg(obj, &obj->mm.get_page, n, offset, false);
+ return __i915_gem_object_get_sg(obj, &obj->mm.get_page, n, offset);
}
+#define i915_gem_object_get_sg(obj, n, offset) ({ \
+ exactly_pgoff_t(n); \
+ (i915_gem_object_get_sg)(obj, n, offset); \
+})
+
static inline struct scatterlist *
-i915_gem_object_get_sg_dma(struct drm_i915_gem_object *obj,
- unsigned int n,
+i915_gem_object_get_sg_dma(struct drm_i915_gem_object *obj, pgoff_t n,
unsigned int *offset)
{
- return __i915_gem_object_get_sg(obj, &obj->mm.get_dma_page, n, offset, true);
+ return __i915_gem_object_get_sg(obj, &obj->mm.get_dma_page, n, offset);
}
+#define i915_gem_object_get_sg_dma(obj, n, offset) ({ \
+ exactly_pgoff_t(n); \
+ (i915_gem_object_get_sg_dma)(obj, n, offset); \
+})
+
struct page *
-i915_gem_object_get_page(struct drm_i915_gem_object *obj,
- unsigned int n);
+i915_gem_object_get_page(struct drm_i915_gem_object *obj, pgoff_t n);
+
+#define i915_gem_object_get_page(obj, n) ({ \
+ exactly_pgoff_t(n); \
+ (i915_gem_object_get_page)(obj, n); \
+})
struct page *
-i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj,
- unsigned int n);
+i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj, pgoff_t n);
+
+#define i915_gem_object_get_dirty_page(obj, n) ({ \
+ exactly_pgoff_t(n); \
+ (i915_gem_object_get_dirty_page)(obj, n); \
+})
dma_addr_t
-i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj,
- unsigned long n,
+i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj, pgoff_t n,
unsigned int *len);
+#define i915_gem_object_get_dma_address_len(obj, n, len) ({ \
+ exactly_pgoff_t(n); \
+ (i915_gem_object_get_dma_address_len)(obj, n, len); \
+})
+
dma_addr_t
-i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,
- unsigned long n);
+i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj, pgoff_t n);
+
+#define i915_gem_object_get_dma_address(obj, n) ({ \
+ exactly_pgoff_t(n); \
+ (i915_gem_object_get_dma_address)(obj, n); \
+})
void __i915_gem_object_set_pages(struct drm_i915_gem_object *obj,
struct sg_table *pages,
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_pages.c b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
index 97c820eee115..1d1edcb3514b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_pages.c
@@ -503,14 +503,16 @@ void __i915_gem_object_release_map(struct drm_i915_gem_object *obj)
}
struct scatterlist *
-__i915_gem_object_get_sg(struct drm_i915_gem_object *obj,
+(__i915_gem_object_get_sg)(struct drm_i915_gem_object *obj,
struct i915_gem_object_page_iter *iter,
- unsigned int n,
- unsigned int *offset,
- bool dma)
+ pgoff_t n,
+ unsigned int *offset)
+
{
- struct scatterlist *sg;
+ const bool dma = iter == &obj->mm.get_dma_page ||
+ iter == &obj->ttm.get_io_page;
unsigned int idx, count;
+ struct scatterlist *sg;
might_sleep();
GEM_BUG_ON(n >= obj->base.size >> PAGE_SHIFT);
@@ -618,7 +620,7 @@ __i915_gem_object_get_sg(struct drm_i915_gem_object *obj,
}
struct page *
-i915_gem_object_get_page(struct drm_i915_gem_object *obj, unsigned int n)
+(i915_gem_object_get_page)(struct drm_i915_gem_object *obj, pgoff_t n)
{
struct scatterlist *sg;
unsigned int offset;
@@ -631,8 +633,7 @@ i915_gem_object_get_page(struct drm_i915_gem_object *obj, unsigned int n)
/* Like i915_gem_object_get_page(), but mark the returned page dirty */
struct page *
-i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj,
- unsigned int n)
+(i915_gem_object_get_dirty_page)(struct drm_i915_gem_object *obj, pgoff_t n)
{
struct page *page;
@@ -644,9 +645,8 @@ i915_gem_object_get_dirty_page(struct drm_i915_gem_object *obj,
}
dma_addr_t
-i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj,
- unsigned long n,
- unsigned int *len)
+(i915_gem_object_get_dma_address_len)(struct drm_i915_gem_object *obj,
+ pgoff_t n, unsigned int *len)
{
struct scatterlist *sg;
unsigned int offset;
@@ -660,8 +660,7 @@ i915_gem_object_get_dma_address_len(struct drm_i915_gem_object *obj,
}
dma_addr_t
-i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,
- unsigned long n)
+(i915_gem_object_get_dma_address)(struct drm_i915_gem_object *obj, pgoff_t n)
{
return i915_gem_object_get_dma_address_len(obj, n, NULL);
}
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
index 4c25d9b2f138..bcdbefd8f269 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c
@@ -711,7 +711,7 @@ static unsigned long i915_ttm_io_mem_pfn(struct ttm_buffer_object *bo,
GEM_WARN_ON(bo->ttm);
base = obj->mm.region->iomap.base - obj->mm.region->region.start;
- sg = __i915_gem_object_get_sg(obj, &obj->ttm.get_io_page, page_offset, &ofs, true);
+ sg = __i915_gem_object_get_sg(obj, &obj->ttm.get_io_page, page_offset, &ofs);
return ((base + sg_dma_address(sg)) >> PAGE_SHIFT) + ofs;
}
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c
index 93a67422ca3b..84d6edd9c204 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_context.c
@@ -455,7 +455,8 @@ static int gpu_fill(struct intel_context *ce,
static int cpu_fill(struct drm_i915_gem_object *obj, u32 value)
{
const bool has_llc = HAS_LLC(to_i915(obj->base.dev));
- unsigned int n, m, need_flush;
+ unsigned int need_flush;
+ unsigned long n, m;
int err;
i915_gem_object_lock(obj, NULL);
@@ -485,7 +486,8 @@ static int cpu_fill(struct drm_i915_gem_object *obj, u32 value)
static noinline int cpu_check(struct drm_i915_gem_object *obj,
unsigned int idx, unsigned int max)
{
- unsigned int n, m, needs_flush;
+ unsigned int needs_flush;
+ unsigned long n;
int err;
i915_gem_object_lock(obj, NULL);
@@ -494,7 +496,7 @@ static noinline int cpu_check(struct drm_i915_gem_object *obj,
goto out_unlock;
for (n = 0; n < real_page_count(obj); n++) {
- u32 *map;
+ u32 *map, m;
map = kmap_atomic(i915_gem_object_get_page(obj, n));
if (needs_flush & CLFLUSH_BEFORE)
@@ -502,7 +504,7 @@ static noinline int cpu_check(struct drm_i915_gem_object *obj,
for (m = 0; m < max; m++) {
if (map[m] != m) {
- pr_err("%pS: Invalid value at object %d page %d/%ld, offset %d/%d: found %x expected %x\n",
+ pr_err("%pS: Invalid value at object %d page %ld/%ld, offset %d/%d: found %x expected %x\n",
__builtin_return_address(0), idx,
n, real_page_count(obj), m, max,
map[m], m);
@@ -513,7 +515,7 @@ static noinline int cpu_check(struct drm_i915_gem_object *obj,
for (; m < DW_PER_PAGE; m++) {
if (map[m] != STACK_MAGIC) {
- pr_err("%pS: Invalid value at object %d page %d, offset %d: found %x expected %x (uninitialised)\n",
+ pr_err("%pS: Invalid value at object %d page %ld, offset %d: found %x expected %x (uninitialised)\n",
__builtin_return_address(0), idx, n, m,
map[m], STACK_MAGIC);
err = -EINVAL;
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
index 5bc93a1ce3e3..b674c1d7a045 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_mman.c
@@ -93,11 +93,11 @@ static int check_partial_mapping(struct drm_i915_gem_object *obj,
struct drm_i915_private *i915 = to_i915(obj->base.dev);
struct i915_ggtt_view view;
struct i915_vma *vma;
+ unsigned long offset;
unsigned long page;
u32 __iomem *io;
struct page *p;
unsigned int n;
- u64 offset;
u32 *cpu;
int err;
@@ -154,7 +154,7 @@ static int check_partial_mapping(struct drm_i915_gem_object *obj,
cpu = kmap(p) + offset_in_page(offset);
drm_clflush_virt_range(cpu, sizeof(*cpu));
if (*cpu != (u32)page) {
- pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%llu + %u [0x%llx]) of 0x%x, found 0x%x\n",
+ pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%lu + %u [0x%lx]) of 0x%x, found 0x%x\n",
page, n,
view.partial.offset,
view.partial.size,
@@ -210,10 +210,10 @@ static int check_partial_mappings(struct drm_i915_gem_object *obj,
for_each_prime_number_from(page, 1, npages) {
struct i915_ggtt_view view =
compute_partial_view(obj, page, MIN_CHUNK_PAGES);
+ unsigned long offset;
u32 __iomem *io;
struct page *p;
unsigned int n;
- u64 offset;
u32 *cpu;
GEM_BUG_ON(view.partial.size > nreal);
@@ -250,7 +250,7 @@ static int check_partial_mappings(struct drm_i915_gem_object *obj,
cpu = kmap(p) + offset_in_page(offset);
drm_clflush_virt_range(cpu, sizeof(*cpu));
if (*cpu != (u32)page) {
- pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%llu + %u [0x%llx]) of 0x%x, found 0x%x\n",
+ pr_err("Partial view for %lu [%u] (offset=%llu, size=%u [%llu, row size %u], fence=%d, tiling=%d, stride=%d) misalignment, expected write to page (%lu + %u [0x%lx]) of 0x%x, found 0x%x\n",
page, n,
view.partial.offset,
view.partial.size,
diff --git a/drivers/gpu/drm/i915/gem/selftests/i915_gem_object.c b/drivers/gpu/drm/i915/gem/selftests/i915_gem_object.c
index fe0a890775e2..bf30763ee6bc 100644
--- a/drivers/gpu/drm/i915/gem/selftests/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/selftests/i915_gem_object.c
@@ -33,10 +33,10 @@ static int igt_gem_object(void *arg)
static int igt_gem_huge(void *arg)
{
- const unsigned int nreal = 509; /* just to be awkward */
+ const unsigned long nreal = 509; /* just to be awkward */
struct drm_i915_private *i915 = arg;
struct drm_i915_gem_object *obj;
- unsigned int n;
+ unsigned long n;
int err;
/* Basic sanitycheck of our huge fake object allocation */
@@ -49,7 +49,7 @@ static int igt_gem_huge(void *arg)
err = i915_gem_object_pin_pages_unlocked(obj);
if (err) {
- pr_err("Failed to allocate %u pages (%lu total), err=%d\n",
+ pr_err("Failed to allocate %lu pages (%lu total), err=%d\n",
nreal, obj->base.size / PAGE_SIZE, err);
goto out;
}
@@ -57,7 +57,7 @@ static int igt_gem_huge(void *arg)
for (n = 0; n < obj->base.size / PAGE_SIZE; n++) {
if (i915_gem_object_get_page(obj, n) !=
i915_gem_object_get_page(obj, n % nreal)) {
- pr_err("Page lookup mismatch at index %u [%u]\n",
+ pr_err("Page lookup mismatch at index %lu [%lu]\n",
n, n % nreal);
err = -EINVAL;
goto out_unpin;
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 702e5b89be22..dba58a3c3238 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -229,8 +229,9 @@ i915_gem_shmem_pread(struct drm_i915_gem_object *obj,
struct drm_i915_gem_pread *args)
{
unsigned int needs_clflush;
- unsigned int idx, offset;
char __user *user_data;
+ unsigned long offset;
+ pgoff_t idx;
u64 remain;
int ret;
@@ -383,13 +384,17 @@ i915_gem_gtt_pread(struct drm_i915_gem_object *obj,
{
struct drm_i915_private *i915 = to_i915(obj->base.dev);
struct i915_ggtt *ggtt = to_gt(i915)->ggtt;
+ unsigned long remain, offset;
intel_wakeref_t wakeref;
struct drm_mm_node node;
void __user *user_data;
struct i915_vma *vma;
- u64 remain, offset;
int ret = 0;
+ if (overflows_type(args->size, remain) ||
+ overflows_type(args->offset, offset))
+ return -EINVAL;
+
wakeref = intel_runtime_pm_get(&i915->runtime_pm);
vma = i915_gem_gtt_prepare(obj, &node, false);
@@ -540,13 +545,17 @@ i915_gem_gtt_pwrite_fast(struct drm_i915_gem_object *obj,
struct drm_i915_private *i915 = to_i915(obj->base.dev);
struct i915_ggtt *ggtt = to_gt(i915)->ggtt;
struct intel_runtime_pm *rpm = &i915->runtime_pm;
+ unsigned long remain, offset;
intel_wakeref_t wakeref;
struct drm_mm_node node;
struct i915_vma *vma;
- u64 remain, offset;
void __user *user_data;
int ret = 0;
+ if (overflows_type(args->size, remain) ||
+ overflows_type(args->offset, offset))
+ return -EINVAL;
+
if (i915_gem_object_has_struct_page(obj)) {
/*
* Avoid waking the device up if we can fallback, as
@@ -654,8 +663,9 @@ i915_gem_shmem_pwrite(struct drm_i915_gem_object *obj,
{
unsigned int partial_cacheline_write;
unsigned int needs_clflush;
- unsigned int offset, idx;
void __user *user_data;
+ unsigned long offset;
+ pgoff_t idx;
u64 remain;
int ret;
diff --git a/drivers/gpu/drm/i915/i915_utils.h b/drivers/gpu/drm/i915/i915_utils.h
index ea7648e3aa0e..b0b24f352fa9 100644
--- a/drivers/gpu/drm/i915/i915_utils.h
+++ b/drivers/gpu/drm/i915/i915_utils.h
@@ -441,4 +441,10 @@ static inline bool i915_run_as_guest(void)
bool i915_vtd_active(struct drm_i915_private *i915);
+/* A poor man's -Wconversion: only allow variables of an exact type. */
+#define exact_type(T, n) \
+ BUILD_BUG_ON(!__builtin_constant_p(n) && !__builtin_types_compatible_p(T, typeof(n)))
+
+#define exactly_pgoff_t(n) exact_type(pgoff_t, n)
+
#endif /* !__I915_UTILS_H */
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 0bffb70b3c5f..686aa0214e68 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -902,7 +902,7 @@ rotate_pages(struct drm_i915_gem_object *obj, unsigned int offset,
struct sg_table *st, struct scatterlist *sg)
{
unsigned int column, row;
- unsigned int src_idx;
+ pgoff_t src_idx;
for (column = 0; column < width; column++) {
unsigned int left;
@@ -1008,7 +1008,7 @@ add_padding_pages(unsigned int count,
static struct scatterlist *
remap_tiled_color_plane_pages(struct drm_i915_gem_object *obj,
- unsigned int offset, unsigned int alignment_pad,
+ unsigned long offset, unsigned int alignment_pad,
unsigned int width, unsigned int height,
unsigned int src_stride, unsigned int dst_stride,
struct sg_table *st, struct scatterlist *sg,
@@ -1067,7 +1067,7 @@ remap_tiled_color_plane_pages(struct drm_i915_gem_object *obj,
static struct scatterlist *
remap_contiguous_pages(struct drm_i915_gem_object *obj,
- unsigned int obj_offset,
+ pgoff_t obj_offset,
unsigned int count,
struct sg_table *st, struct scatterlist *sg)
{
@@ -1100,7 +1100,7 @@ remap_contiguous_pages(struct drm_i915_gem_object *obj,
static struct scatterlist *
remap_linear_color_plane_pages(struct drm_i915_gem_object *obj,
- unsigned int obj_offset, unsigned int alignment_pad,
+ pgoff_t obj_offset, unsigned int alignment_pad,
unsigned int size,
struct sg_table *st, struct scatterlist *sg,
unsigned int *gtt_offset)
--
2.34.1
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