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-rw-r--r--meta/recipes-core/glibc/glibc/mte-backports.patch1238
1 files changed, 0 insertions, 1238 deletions
diff --git a/meta/recipes-core/glibc/glibc/mte-backports.patch b/meta/recipes-core/glibc/glibc/mte-backports.patch
deleted file mode 100644
index d9604fdf45..0000000000
--- a/meta/recipes-core/glibc/glibc/mte-backports.patch
+++ /dev/null
@@ -1,1238 +0,0 @@
-Backport a number of patches from master to improve Arm MTE support.
-
-Upstream-Status: Backport [will be in 2.34]
-Signed-off-by: Ross Burton <ross.burton@arm.com>
-
-From 2643466c2928a93de7b80a61f6a8f61a653862e1 Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Thu, 11 Mar 2021 14:09:56 +0000
-Subject: [PATCH 01/11] malloc: Fix a potential realloc issue with memory
- tagging
-
-At an _int_free call site in realloc the wrong size was used for tag
-clearing: the chunk header of the next chunk was also cleared which
-in practice may work, but logically wrong.
-
-The tag clearing is moved before the memcpy to save a tag computation,
-this avoids a chunk2mem. Another chunk2mem is removed because newmem
-does not have to be recomputed. Whitespaces got fixed too.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/malloc.c | 14 +++++++-------
- 1 file changed, 7 insertions(+), 7 deletions(-)
-
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 8f8f12c276..51cec67e55 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -4851,14 +4851,14 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T oldsize,
- }
- else
- {
-- void *oldmem = chunk2mem (oldp);
-+ void *oldmem = chunk2rawmem (oldp);
-+ size_t sz = CHUNK_AVAILABLE_SIZE (oldp) - CHUNK_HDR_SZ;
-+ (void) TAG_REGION (oldmem, sz);
- newmem = TAG_NEW_USABLE (newmem);
-- memcpy (newmem, oldmem,
-- CHUNK_AVAILABLE_SIZE (oldp) - CHUNK_HDR_SZ);
-- (void) TAG_REGION (chunk2rawmem (oldp), oldsize);
-- _int_free (av, oldp, 1);
-- check_inuse_chunk (av, newp);
-- return chunk2mem (newp);
-+ memcpy (newmem, oldmem, sz);
-+ _int_free (av, oldp, 1);
-+ check_inuse_chunk (av, newp);
-+ return newmem;
- }
- }
- }
---
-2.25.1
-
-
-From 32f3132be063e4b16a5cdb058980af354126e2f4 Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Thu, 28 Jan 2021 17:34:36 +0000
-Subject: [PATCH 02/11] malloc: Move MTAG_MMAP_FLAGS definition
-
-This is only used internally in malloc.c, the extern declaration
-was wrong, __mtag_mmap_flags has internal linkage.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- include/malloc.h | 7 -------
- malloc/malloc.c | 2 ++
- 2 files changed, 2 insertions(+), 7 deletions(-)
-
-diff --git a/include/malloc.h b/include/malloc.h
-index 7ae08d53d3..b77761f74d 100644
---- a/include/malloc.h
-+++ b/include/malloc.h
-@@ -16,11 +16,4 @@ typedef struct malloc_state *mstate;
-
- # endif /* !_ISOMAC */
-
--#ifdef USE_MTAG
--extern int __mtag_mmap_flags;
--#define MTAG_MMAP_FLAGS __mtag_mmap_flags
--#else
--#define MTAG_MMAP_FLAGS 0
--#endif
--
- #endif
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 51cec67e55..61c25d0f93 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -463,11 +463,13 @@ static void *(*__tag_region)(void *, size_t) = __default_tag_region;
- static void *(*__tag_new_usable)(void *) = __default_tag_nop;
- static void *(*__tag_at)(void *) = __default_tag_nop;
-
-+# define MTAG_MMAP_FLAGS __mtag_mmap_flags
- # define TAG_NEW_MEMSET(ptr, val, size) __tag_new_memset (ptr, val, size)
- # define TAG_REGION(ptr, size) __tag_region (ptr, size)
- # define TAG_NEW_USABLE(ptr) __tag_new_usable (ptr)
- # define TAG_AT(ptr) __tag_at (ptr)
- #else
-+# define MTAG_MMAP_FLAGS 0
- # define TAG_NEW_MEMSET(ptr, val, size) memset (ptr, val, size)
- # define TAG_REGION(ptr, size) (ptr)
- # define TAG_NEW_USABLE(ptr) (ptr)
---
-2.25.1
-
-
-From 4b13f77fb97f9618a7868ab767d05e0c2d7c6f6f Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Thu, 4 Feb 2021 11:38:23 +0000
-Subject: [PATCH 03/11] malloc: Simplify __mtag_tag_new_usable
-
-The chunk cannot be a dumped one here. The only non-obvious cases
-are free and realloc which may be called on a dumped area chunk,
-but in both cases it can be verified that tagging is already
-avoided for dumped area chunks.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/arena.c | 5 -----
- 1 file changed, 5 deletions(-)
-
-diff --git a/malloc/arena.c b/malloc/arena.c
-index bf17be27d4..0777dc70c6 100644
---- a/malloc/arena.c
-+++ b/malloc/arena.c
-@@ -298,11 +298,6 @@ __mtag_tag_new_usable (void *ptr)
- if (ptr)
- {
- mchunkptr cp = mem2chunk(ptr);
-- /* This likely will never happen, but we can't handle retagging
-- chunks from the dumped main arena. So just return the
-- existing pointer. */
-- if (DUMPED_MAIN_ARENA_CHUNK (cp))
-- return ptr;
- ptr = __libc_mtag_tag_region (__libc_mtag_new_tag (ptr),
- CHUNK_AVAILABLE_SIZE (cp) - CHUNK_HDR_SZ);
- }
---
-2.25.1
-
-
-From 4f05837ba6934c5b8bbc6738f8883890493f50b6 Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Thu, 4 Feb 2021 11:52:14 +0000
-Subject: [PATCH 04/11] malloc: Avoid taggig mmaped memory on free
-
-Either the memory belongs to the dumped area, in which case we don't
-want to tag (the dumped area has the same tag as malloc internal data
-so tagging is unnecessary, but chunks there may not have the right
-alignment for the tag granule), or the memory will be unmapped
-immediately (and thus tagging is not useful).
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/malloc.c | 7 ++++---
- 1 file changed, 4 insertions(+), 3 deletions(-)
-
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 61c25d0f93..ecb87350b0 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -3284,9 +3284,6 @@ __libc_free (void *mem)
-
- p = mem2chunk (mem);
-
-- /* Mark the chunk as belonging to the library again. */
-- (void)TAG_REGION (chunk2rawmem (p), CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
--
- if (chunk_is_mmapped (p)) /* release mmapped memory. */
- {
- /* See if the dynamic brk/mmap threshold needs adjusting.
-@@ -3307,6 +3304,10 @@ __libc_free (void *mem)
- {
- MAYBE_INIT_TCACHE ();
-
-+ /* Mark the chunk as belonging to the library again. */
-+ (void)TAG_REGION (chunk2rawmem (p),
-+ CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
-+
- ar_ptr = arena_for_chunk (p);
- _int_free (ar_ptr, p, 0);
- }
---
-2.25.1
-
-
-From 673fad3798846101b77a89595cfa17f334a1c898 Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Tue, 16 Feb 2021 14:12:25 +0000
-Subject: [PATCH 05/11] malloc: Refactor TAG_ macros to avoid indirection
-
-This does not change behaviour, just removes one layer of indirection
-in the internal memory tagging logic.
-
-Use tag_ and mtag_ prefixes instead of __tag_ and __mtag_ since these
-are all symbols with internal linkage, private to malloc.c, so there
-is no user namespace pollution issue.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/arena.c | 16 +++++-----
- malloc/hooks.c | 10 +++---
- malloc/malloc.c | 81 +++++++++++++++++++++++--------------------------
- 3 files changed, 51 insertions(+), 56 deletions(-)
-
-diff --git a/malloc/arena.c b/malloc/arena.c
-index 0777dc70c6..d0778fea92 100644
---- a/malloc/arena.c
-+++ b/malloc/arena.c
-@@ -332,12 +332,12 @@ ptmalloc_init (void)
- if (__MTAG_SBRK_UNTAGGED)
- __morecore = __failing_morecore;
-
-- __mtag_mmap_flags = __MTAG_MMAP_FLAGS;
-- __tag_new_memset = __mtag_tag_new_memset;
-- __tag_region = __libc_mtag_tag_region;
-- __tag_new_usable = __mtag_tag_new_usable;
-- __tag_at = __libc_mtag_address_get_tag;
-- __mtag_granule_mask = ~(size_t)(__MTAG_GRANULE_SIZE - 1);
-+ mtag_mmap_flags = __MTAG_MMAP_FLAGS;
-+ tag_new_memset = __mtag_tag_new_memset;
-+ tag_region = __libc_mtag_tag_region;
-+ tag_new_usable = __mtag_tag_new_usable;
-+ tag_at = __libc_mtag_address_get_tag;
-+ mtag_granule_mask = ~(size_t)(__MTAG_GRANULE_SIZE - 1);
- }
- #endif
-
-@@ -557,7 +557,7 @@ new_heap (size_t size, size_t top_pad)
- }
- }
- }
-- if (__mprotect (p2, size, MTAG_MMAP_FLAGS | PROT_READ | PROT_WRITE) != 0)
-+ if (__mprotect (p2, size, mtag_mmap_flags | PROT_READ | PROT_WRITE) != 0)
- {
- __munmap (p2, HEAP_MAX_SIZE);
- return 0;
-@@ -587,7 +587,7 @@ grow_heap (heap_info *h, long diff)
- {
- if (__mprotect ((char *) h + h->mprotect_size,
- (unsigned long) new_size - h->mprotect_size,
-- MTAG_MMAP_FLAGS | PROT_READ | PROT_WRITE) != 0)
-+ mtag_mmap_flags | PROT_READ | PROT_WRITE) != 0)
- return -2;
-
- h->mprotect_size = new_size;
-diff --git a/malloc/hooks.c b/malloc/hooks.c
-index efec05f0a8..d8e304c31c 100644
---- a/malloc/hooks.c
-+++ b/malloc/hooks.c
-@@ -68,7 +68,7 @@ __malloc_check_init (void)
- tags, so fetch the tag at each location before dereferencing
- it. */
- #define SAFE_CHAR_OFFSET(p,offset) \
-- ((unsigned char *) TAG_AT (((unsigned char *) p) + offset))
-+ ((unsigned char *) tag_at (((unsigned char *) p) + offset))
-
- /* A simple, standard set of debugging hooks. Overhead is `only' one
- byte per chunk; still this will catch most cases of double frees or
-@@ -249,7 +249,7 @@ malloc_check (size_t sz, const void *caller)
- top_check ();
- victim = _int_malloc (&main_arena, nb);
- __libc_lock_unlock (main_arena.mutex);
-- return mem2mem_check (TAG_NEW_USABLE (victim), sz);
-+ return mem2mem_check (tag_new_usable (victim), sz);
- }
-
- static void
-@@ -280,7 +280,7 @@ free_check (void *mem, const void *caller)
- else
- {
- /* Mark the chunk as belonging to the library again. */
-- (void)TAG_REGION (chunk2rawmem (p), CHUNK_AVAILABLE_SIZE (p)
-+ (void)tag_region (chunk2rawmem (p), CHUNK_AVAILABLE_SIZE (p)
- - CHUNK_HDR_SZ);
- _int_free (&main_arena, p, 1);
- __libc_lock_unlock (main_arena.mutex);
-@@ -375,7 +375,7 @@ invert:
-
- __libc_lock_unlock (main_arena.mutex);
-
-- return mem2mem_check (TAG_NEW_USABLE (newmem), bytes);
-+ return mem2mem_check (tag_new_usable (newmem), bytes);
- }
-
- static void *
-@@ -417,7 +417,7 @@ memalign_check (size_t alignment, size_t bytes, const void *caller)
- top_check ();
- mem = _int_memalign (&main_arena, alignment, bytes + 1);
- __libc_lock_unlock (main_arena.mutex);
-- return mem2mem_check (TAG_NEW_USABLE (mem), bytes);
-+ return mem2mem_check (tag_new_usable (mem), bytes);
- }
-
- #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_25)
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index ecb87350b0..62d00f54cc 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -413,26 +413,26 @@ void *(*__morecore)(ptrdiff_t) = __default_morecore;
- operations can continue to be used. Support macros are used to do
- this:
-
-- void *TAG_NEW_MEMSET (void *ptr, int, val, size_t size)
-+ void *tag_new_memset (void *ptr, int, val, size_t size)
-
- Has the same interface as memset(), but additionally allocates a
- new tag, colors the memory with that tag and returns a pointer that
- is correctly colored for that location. The non-tagging version
- will simply call memset.
-
-- void *TAG_REGION (void *ptr, size_t size)
-+ void *tag_region (void *ptr, size_t size)
-
- Color the region of memory pointed to by PTR and size SIZE with
- the color of PTR. Returns the original pointer.
-
-- void *TAG_NEW_USABLE (void *ptr)
-+ void *tag_new_usable (void *ptr)
-
- Allocate a new random color and use it to color the user region of
- a chunk; this may include data from the subsequent chunk's header
- if tagging is sufficiently fine grained. Returns PTR suitably
- recolored for accessing the memory there.
-
-- void *TAG_AT (void *ptr)
-+ void *tag_at (void *ptr)
-
- Read the current color of the memory at the address pointed to by
- PTR (ignoring it's current color) and return PTR recolored to that
-@@ -455,25 +455,20 @@ __default_tag_nop (void *ptr)
- return ptr;
- }
-
--static int __mtag_mmap_flags = 0;
--static size_t __mtag_granule_mask = ~(size_t)0;
-+static int mtag_mmap_flags = 0;
-+static size_t mtag_granule_mask = ~(size_t)0;
-
--static void *(*__tag_new_memset)(void *, int, size_t) = memset;
--static void *(*__tag_region)(void *, size_t) = __default_tag_region;
--static void *(*__tag_new_usable)(void *) = __default_tag_nop;
--static void *(*__tag_at)(void *) = __default_tag_nop;
-+static void *(*tag_new_memset)(void *, int, size_t) = memset;
-+static void *(*tag_region)(void *, size_t) = __default_tag_region;
-+static void *(*tag_new_usable)(void *) = __default_tag_nop;
-+static void *(*tag_at)(void *) = __default_tag_nop;
-
--# define MTAG_MMAP_FLAGS __mtag_mmap_flags
--# define TAG_NEW_MEMSET(ptr, val, size) __tag_new_memset (ptr, val, size)
--# define TAG_REGION(ptr, size) __tag_region (ptr, size)
--# define TAG_NEW_USABLE(ptr) __tag_new_usable (ptr)
--# define TAG_AT(ptr) __tag_at (ptr)
- #else
--# define MTAG_MMAP_FLAGS 0
--# define TAG_NEW_MEMSET(ptr, val, size) memset (ptr, val, size)
--# define TAG_REGION(ptr, size) (ptr)
--# define TAG_NEW_USABLE(ptr) (ptr)
--# define TAG_AT(ptr) (ptr)
-+# define mtag_mmap_flags 0
-+# define tag_new_memset(ptr, val, size) memset (ptr, val, size)
-+# define tag_region(ptr, size) (ptr)
-+# define tag_new_usable(ptr) (ptr)
-+# define tag_at(ptr) (ptr)
- #endif
-
- #include <string.h>
-@@ -1305,8 +1300,8 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- /* Convert between user mem pointers and chunk pointers, updating any
- memory tags on the pointer to respect the tag value at that
- location. */
--#define chunk2mem(p) ((void*)TAG_AT (((char*)(p) + CHUNK_HDR_SZ)))
--#define mem2chunk(mem) ((mchunkptr)TAG_AT (((char*)(mem) - CHUNK_HDR_SZ)))
-+#define chunk2mem(p) ((void *)tag_at (((char*)(p) + CHUNK_HDR_SZ)))
-+#define mem2chunk(mem) ((mchunkptr)tag_at (((char*)(mem) - CHUNK_HDR_SZ)))
-
- /* The smallest possible chunk */
- #define MIN_CHUNK_SIZE (offsetof(struct malloc_chunk, fd_nextsize))
-@@ -1337,7 +1332,7 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- #ifdef USE_MTAG
- #define CHUNK_AVAILABLE_SIZE(p) \
- ((chunksize (p) + (chunk_is_mmapped (p) ? 0 : SIZE_SZ)) \
-- & __mtag_granule_mask)
-+ & mtag_granule_mask)
- #else
- #define CHUNK_AVAILABLE_SIZE(p) \
- (chunksize (p) + (chunk_is_mmapped (p) ? 0 : SIZE_SZ))
-@@ -1361,7 +1356,7 @@ checked_request2size (size_t req, size_t *sz) __nonnull (1)
- number. Ideally, this would be part of request2size(), but that
- must be a macro that produces a compile time constant if passed
- a constant literal. */
-- req = (req + ~__mtag_granule_mask) & __mtag_granule_mask;
-+ req = (req + ~mtag_granule_mask) & mtag_granule_mask;
- #endif
-
- *sz = request2size (req);
-@@ -2467,7 +2462,7 @@ sysmalloc (INTERNAL_SIZE_T nb, mstate av)
- if ((unsigned long) (size) > (unsigned long) (nb))
- {
- mm = (char *) (MMAP (0, size,
-- MTAG_MMAP_FLAGS | PROT_READ | PROT_WRITE, 0));
-+ mtag_mmap_flags | PROT_READ | PROT_WRITE, 0));
-
- if (mm != MAP_FAILED)
- {
-@@ -2665,7 +2660,7 @@ sysmalloc (INTERNAL_SIZE_T nb, mstate av)
- if ((unsigned long) (size) > (unsigned long) (nb))
- {
- char *mbrk = (char *) (MMAP (0, size,
-- MTAG_MMAP_FLAGS | PROT_READ | PROT_WRITE,
-+ mtag_mmap_flags | PROT_READ | PROT_WRITE,
- 0));
-
- if (mbrk != MAP_FAILED)
-@@ -3221,14 +3216,14 @@ __libc_malloc (size_t bytes)
- && tcache->counts[tc_idx] > 0)
- {
- victim = tcache_get (tc_idx);
-- return TAG_NEW_USABLE (victim);
-+ return tag_new_usable (victim);
- }
- DIAG_POP_NEEDS_COMMENT;
- #endif
-
- if (SINGLE_THREAD_P)
- {
-- victim = TAG_NEW_USABLE (_int_malloc (&main_arena, bytes));
-+ victim = tag_new_usable (_int_malloc (&main_arena, bytes));
- assert (!victim || chunk_is_mmapped (mem2chunk (victim)) ||
- &main_arena == arena_for_chunk (mem2chunk (victim)));
- return victim;
-@@ -3249,7 +3244,7 @@ __libc_malloc (size_t bytes)
- if (ar_ptr != NULL)
- __libc_lock_unlock (ar_ptr->mutex);
-
-- victim = TAG_NEW_USABLE (victim);
-+ victim = tag_new_usable (victim);
-
- assert (!victim || chunk_is_mmapped (mem2chunk (victim)) ||
- ar_ptr == arena_for_chunk (mem2chunk (victim)));
-@@ -3305,7 +3300,7 @@ __libc_free (void *mem)
- MAYBE_INIT_TCACHE ();
-
- /* Mark the chunk as belonging to the library again. */
-- (void)TAG_REGION (chunk2rawmem (p),
-+ (void)tag_region (chunk2rawmem (p),
- CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
-
- ar_ptr = arena_for_chunk (p);
-@@ -3408,7 +3403,7 @@ __libc_realloc (void *oldmem, size_t bytes)
- reused. There's a performance hit for both us and the
- caller for doing this, so we might want to
- reconsider. */
-- return TAG_NEW_USABLE (newmem);
-+ return tag_new_usable (newmem);
- }
- #endif
- /* Note the extra SIZE_SZ overhead. */
-@@ -3451,7 +3446,7 @@ __libc_realloc (void *oldmem, size_t bytes)
- {
- size_t sz = CHUNK_AVAILABLE_SIZE (oldp) - CHUNK_HDR_SZ;
- memcpy (newp, oldmem, sz);
-- (void) TAG_REGION (chunk2rawmem (oldp), sz);
-+ (void) tag_region (chunk2rawmem (oldp), sz);
- _int_free (ar_ptr, oldp, 0);
- }
- }
-@@ -3509,7 +3504,7 @@ _mid_memalign (size_t alignment, size_t bytes, void *address)
- p = _int_memalign (&main_arena, alignment, bytes);
- assert (!p || chunk_is_mmapped (mem2chunk (p)) ||
- &main_arena == arena_for_chunk (mem2chunk (p)));
-- return TAG_NEW_USABLE (p);
-+ return tag_new_usable (p);
- }
-
- arena_get (ar_ptr, bytes + alignment + MINSIZE);
-@@ -3527,7 +3522,7 @@ _mid_memalign (size_t alignment, size_t bytes, void *address)
-
- assert (!p || chunk_is_mmapped (mem2chunk (p)) ||
- ar_ptr == arena_for_chunk (mem2chunk (p)));
-- return TAG_NEW_USABLE (p);
-+ return tag_new_usable (p);
- }
- /* For ISO C11. */
- weak_alias (__libc_memalign, aligned_alloc)
-@@ -3544,7 +3539,7 @@ __libc_valloc (size_t bytes)
- void *address = RETURN_ADDRESS (0);
- size_t pagesize = GLRO (dl_pagesize);
- p = _mid_memalign (pagesize, bytes, address);
-- return TAG_NEW_USABLE (p);
-+ return tag_new_usable (p);
- }
-
- void *
-@@ -3569,7 +3564,7 @@ __libc_pvalloc (size_t bytes)
- rounded_bytes = rounded_bytes & -(pagesize - 1);
-
- p = _mid_memalign (pagesize, rounded_bytes, address);
-- return TAG_NEW_USABLE (p);
-+ return tag_new_usable (p);
- }
-
- void *
-@@ -3666,7 +3661,7 @@ __libc_calloc (size_t n, size_t elem_size)
- regardless of MORECORE_CLEARS, so we zero the whole block while
- doing so. */
- #ifdef USE_MTAG
-- return TAG_NEW_MEMSET (mem, 0, CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
-+ return tag_new_memset (mem, 0, CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
- #else
- INTERNAL_SIZE_T csz = chunksize (p);
-
-@@ -4821,7 +4816,7 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T oldsize,
- av->top = chunk_at_offset (oldp, nb);
- set_head (av->top, (newsize - nb) | PREV_INUSE);
- check_inuse_chunk (av, oldp);
-- return TAG_NEW_USABLE (chunk2rawmem (oldp));
-+ return tag_new_usable (chunk2rawmem (oldp));
- }
-
- /* Try to expand forward into next chunk; split off remainder below */
-@@ -4856,8 +4851,8 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T oldsize,
- {
- void *oldmem = chunk2rawmem (oldp);
- size_t sz = CHUNK_AVAILABLE_SIZE (oldp) - CHUNK_HDR_SZ;
-- (void) TAG_REGION (oldmem, sz);
-- newmem = TAG_NEW_USABLE (newmem);
-+ (void) tag_region (oldmem, sz);
-+ newmem = tag_new_usable (newmem);
- memcpy (newmem, oldmem, sz);
- _int_free (av, oldp, 1);
- check_inuse_chunk (av, newp);
-@@ -4881,7 +4876,7 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T oldsize,
- {
- remainder = chunk_at_offset (newp, nb);
- /* Clear any user-space tags before writing the header. */
-- remainder = TAG_REGION (remainder, remainder_size);
-+ remainder = tag_region (remainder, remainder_size);
- set_head_size (newp, nb | (av != &main_arena ? NON_MAIN_ARENA : 0));
- set_head (remainder, remainder_size | PREV_INUSE |
- (av != &main_arena ? NON_MAIN_ARENA : 0));
-@@ -4891,7 +4886,7 @@ _int_realloc(mstate av, mchunkptr oldp, INTERNAL_SIZE_T oldsize,
- }
-
- check_inuse_chunk (av, newp);
-- return TAG_NEW_USABLE (chunk2rawmem (newp));
-+ return tag_new_usable (chunk2rawmem (newp));
- }
-
- /*
-@@ -5108,7 +5103,7 @@ musable (void *mem)
- /* The usable space may be reduced if memory tagging is needed,
- since we cannot share the user-space data with malloc's internal
- data structure. */
-- result &= __mtag_granule_mask;
-+ result &= mtag_granule_mask;
- #endif
- return result;
- }
---
-2.25.1
-
-
-From f0ea41e819f40aacedf25431bedd95da9c5db534 Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Wed, 27 Jan 2021 15:45:43 +0000
-Subject: [PATCH 06/11] malloc: Use global flag instead of function pointer
- dispatch for mtag
-
-A flag check can be faster than function pointers because of how
-branch prediction and speculation works and it can also remove a layer
-of indirection when there is a mismatch between the malloc internal
-tag_* api and __libc_mtag_* target hooks.
-
-Memory tagging wrapper functions are moved to malloc.c from arena.c and
-the logic now checks mmap_enabled. The definition of tag_new_usable is
-moved after chunk related definitions.
-
-This refactoring also allows using mtag_enabled checks instead of
-USE_MTAG ifdefs when memory tagging support only changes code logic
-when memory tagging is enabled at runtime. Note: an "if (false)" code
-block is optimized away even at -O0 by gcc.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/arena.c | 33 +---------------------------
- malloc/malloc.c | 58 ++++++++++++++++++++++++++++++++-----------------
- 2 files changed, 39 insertions(+), 52 deletions(-)
-
-diff --git a/malloc/arena.c b/malloc/arena.c
-index d0778fea92..1e83bb66bd 100644
---- a/malloc/arena.c
-+++ b/malloc/arena.c
-@@ -287,34 +287,6 @@ extern struct dl_open_hook *_dl_open_hook;
- libc_hidden_proto (_dl_open_hook);
- #endif
-
--#ifdef USE_MTAG
--
--/* Generate a new (random) tag value for PTR and tag the memory it
-- points to upto the end of the usable size for the chunk containing
-- it. Return the newly tagged pointer. */
--static void *
--__mtag_tag_new_usable (void *ptr)
--{
-- if (ptr)
-- {
-- mchunkptr cp = mem2chunk(ptr);
-- ptr = __libc_mtag_tag_region (__libc_mtag_new_tag (ptr),
-- CHUNK_AVAILABLE_SIZE (cp) - CHUNK_HDR_SZ);
-- }
-- return ptr;
--}
--
--/* Generate a new (random) tag value for PTR, set the tags for the
-- memory to the new tag and initialize the memory contents to VAL.
-- In practice this function will only be called with VAL=0, but we
-- keep this parameter to maintain the same prototype as memset. */
--static void *
--__mtag_tag_new_memset (void *ptr, int val, size_t size)
--{
-- return __libc_mtag_memset_with_tag (__libc_mtag_new_tag (ptr), val, size);
--}
--#endif
--
- static void
- ptmalloc_init (void)
- {
-@@ -332,11 +304,8 @@ ptmalloc_init (void)
- if (__MTAG_SBRK_UNTAGGED)
- __morecore = __failing_morecore;
-
-+ mtag_enabled = true;
- mtag_mmap_flags = __MTAG_MMAP_FLAGS;
-- tag_new_memset = __mtag_tag_new_memset;
-- tag_region = __libc_mtag_tag_region;
-- tag_new_usable = __mtag_tag_new_usable;
-- tag_at = __libc_mtag_address_get_tag;
- mtag_granule_mask = ~(size_t)(__MTAG_GRANULE_SIZE - 1);
- }
- #endif
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 62d00f54cc..253a919ec5 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -441,35 +441,41 @@ void *(*__morecore)(ptrdiff_t) = __default_morecore;
- */
-
- #ifdef USE_MTAG
-+static bool mtag_enabled = false;
-+static int mtag_mmap_flags = 0;
-+static size_t mtag_granule_mask = ~(size_t)0;
-+#else
-+# define mtag_enabled false
-+# define mtag_mmap_flags 0
-+#endif
-
--/* Default implementaions when memory tagging is supported, but disabled. */
--static void *
--__default_tag_region (void *ptr, size_t size)
-+static __always_inline void *
-+tag_region (void *ptr, size_t size)
- {
-+ if (__glibc_unlikely (mtag_enabled))
-+ return __libc_mtag_tag_region (ptr, size);
- return ptr;
- }
-
--static void *
--__default_tag_nop (void *ptr)
-+static __always_inline void *
-+tag_new_memset (void *ptr, int val, size_t size)
- {
-- return ptr;
-+ if (__glibc_unlikely (mtag_enabled))
-+ return __libc_mtag_memset_with_tag (__libc_mtag_new_tag (ptr), val, size);
-+ return memset (ptr, val, size);
- }
-
--static int mtag_mmap_flags = 0;
--static size_t mtag_granule_mask = ~(size_t)0;
--
--static void *(*tag_new_memset)(void *, int, size_t) = memset;
--static void *(*tag_region)(void *, size_t) = __default_tag_region;
--static void *(*tag_new_usable)(void *) = __default_tag_nop;
--static void *(*tag_at)(void *) = __default_tag_nop;
-+/* Defined later. */
-+static void *
-+tag_new_usable (void *ptr);
-
--#else
--# define mtag_mmap_flags 0
--# define tag_new_memset(ptr, val, size) memset (ptr, val, size)
--# define tag_region(ptr, size) (ptr)
--# define tag_new_usable(ptr) (ptr)
--# define tag_at(ptr) (ptr)
--#endif
-+static __always_inline void *
-+tag_at (void *ptr)
-+{
-+ if (__glibc_unlikely (mtag_enabled))
-+ return __libc_mtag_address_get_tag (ptr);
-+ return ptr;
-+}
-
- #include <string.h>
-
-@@ -1460,6 +1466,18 @@ checked_request2size (size_t req, size_t *sz) __nonnull (1)
- #pragma GCC poison mchunk_size
- #pragma GCC poison mchunk_prev_size
-
-+static __always_inline void *
-+tag_new_usable (void *ptr)
-+{
-+ if (__glibc_unlikely (mtag_enabled) && ptr)
-+ {
-+ mchunkptr cp = mem2chunk(ptr);
-+ ptr = __libc_mtag_tag_region (__libc_mtag_new_tag (ptr),
-+ CHUNK_AVAILABLE_SIZE (cp) - CHUNK_HDR_SZ);
-+ }
-+ return ptr;
-+}
-+
- /*
- -------------------- Internal data structures --------------------
-
---
-2.25.1
-
-
-From 8597244d5c3edbd672b285eea5f6dea833256f9d Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Wed, 17 Feb 2021 10:39:37 +0000
-Subject: [PATCH 07/11] malloc: Ensure the generic mtag hooks are not used
-
-Use inline functions instead of macros, because macros can cause unused
-variable warnings and type conversion issues. We assume these functions
-may appear in the code but only in dead code paths (hidden by a runtime
-check), so it's important that they can compile with correct types, but
-if they are actually used that should be an error.
-
-Currently the hooks are only used when USE_MTAG is true which only
-happens on aarch64 and then the aarch64 specific code is used not this
-generic header. However followup refactoring will allow the hooks to
-be used with !USE_MTAG.
-
-Note: the const qualifier in the comment was wrong: changing tags is a
-write operation.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- sysdeps/generic/libc-mtag.h | 41 ++++++++++++++++++++++++++++---------
- 1 file changed, 31 insertions(+), 10 deletions(-)
-
-diff --git a/sysdeps/generic/libc-mtag.h b/sysdeps/generic/libc-mtag.h
-index 1a866cdc0c..e8fc236b6c 100644
---- a/sysdeps/generic/libc-mtag.h
-+++ b/sysdeps/generic/libc-mtag.h
-@@ -31,22 +31,43 @@
- /* Extra flags to pass to mmap() to request a tagged region of memory. */
- #define __MTAG_MMAP_FLAGS 0
-
-+/* Memory tagging target hooks are only called when memory tagging is
-+ enabled at runtime. The generic definitions here must not be used. */
-+void __libc_mtag_link_error (void);
-+
- /* Set the tags for a region of memory, which must have size and alignment
-- that are multiples of __MTAG_GRANULE_SIZE. Size cannot be zero.
-- void *__libc_mtag_tag_region (const void *, size_t) */
--#define __libc_mtag_tag_region(p, s) (p)
-+ that are multiples of __MTAG_GRANULE_SIZE. Size cannot be zero. */
-+static inline void *
-+__libc_mtag_tag_region (void *p, size_t n)
-+{
-+ __libc_mtag_link_error ();
-+ return p;
-+}
-
- /* Optimized equivalent to __libc_mtag_tag_region followed by memset. */
--#define __libc_mtag_memset_with_tag memset
-+static inline void *
-+__libc_mtag_memset_with_tag (void *p, int c, size_t n)
-+{
-+ __libc_mtag_link_error ();
-+ return memset (p, c, n);
-+}
-
- /* Convert address P to a pointer that is tagged correctly for that
-- location.
-- void *__libc_mtag_address_get_tag (void*) */
--#define __libc_mtag_address_get_tag(p) (p)
-+ location. */
-+static inline void *
-+__libc_mtag_address_get_tag (void *p)
-+{
-+ __libc_mtag_link_error ();
-+ return p;
-+}
-
- /* Assign a new (random) tag to a pointer P (does not adjust the tag on
-- the memory addressed).
-- void *__libc_mtag_new_tag (void*) */
--#define __libc_mtag_new_tag(p) (p)
-+ the memory addressed). */
-+static inline void *
-+__libc_mtag_new_tag (void *p)
-+{
-+ __libc_mtag_link_error ();
-+ return p;
-+}
-
- #endif /* _GENERIC_LIBC_MTAG_H */
---
-2.25.1
-
-
-From 3d9e16280ad881d038aedba0b6fcbd9e78b29072 Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Fri, 29 Jan 2021 17:07:28 +0000
-Subject: [PATCH 08/11] malloc: Only support zeroing and not arbitrary memset
- with mtag
-
-The memset api is suboptimal and does not provide much benefit. Memory
-tagging only needs a zeroing memset (and only for memory that's sized
-and aligned to multiples of the tag granule), so change the internal
-api and the target hooks accordingly. This is to simplify the
-implementation of the target hook.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/malloc.c | 17 ++++++++---------
- sysdeps/aarch64/Makefile | 2 +-
- ...g_memset_tag.S => __mtag_tag_zero_region.S} | 18 +++++++-----------
- sysdeps/aarch64/libc-mtag.h | 4 ++--
- sysdeps/generic/libc-mtag.h | 6 +++---
- 5 files changed, 21 insertions(+), 26 deletions(-)
- rename sysdeps/aarch64/{__mtag_memset_tag.S => __mtag_tag_zero_region.S} (82%)
-
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 253a919ec5..01cf6e9325 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -413,12 +413,11 @@ void *(*__morecore)(ptrdiff_t) = __default_morecore;
- operations can continue to be used. Support macros are used to do
- this:
-
-- void *tag_new_memset (void *ptr, int, val, size_t size)
-+ void *tag_new_zero_region (void *ptr, size_t size)
-
-- Has the same interface as memset(), but additionally allocates a
-- new tag, colors the memory with that tag and returns a pointer that
-- is correctly colored for that location. The non-tagging version
-- will simply call memset.
-+ Allocates a new tag, colors the memory with that tag, zeros the
-+ memory and returns a pointer that is correctly colored for that
-+ location. The non-tagging version will simply call memset with 0.
-
- void *tag_region (void *ptr, size_t size)
-
-@@ -458,11 +457,11 @@ tag_region (void *ptr, size_t size)
- }
-
- static __always_inline void *
--tag_new_memset (void *ptr, int val, size_t size)
-+tag_new_zero_region (void *ptr, size_t size)
- {
- if (__glibc_unlikely (mtag_enabled))
-- return __libc_mtag_memset_with_tag (__libc_mtag_new_tag (ptr), val, size);
-- return memset (ptr, val, size);
-+ return __libc_mtag_tag_zero_region (__libc_mtag_new_tag (ptr), size);
-+ return memset (ptr, 0, size);
- }
-
- /* Defined later. */
-@@ -3679,7 +3678,7 @@ __libc_calloc (size_t n, size_t elem_size)
- regardless of MORECORE_CLEARS, so we zero the whole block while
- doing so. */
- #ifdef USE_MTAG
-- return tag_new_memset (mem, 0, CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
-+ return tag_new_zero_region (mem, CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
- #else
- INTERNAL_SIZE_T csz = chunksize (p);
-
-diff --git a/sysdeps/aarch64/Makefile b/sysdeps/aarch64/Makefile
-index d3ab37a40a..259070cfad 100644
---- a/sysdeps/aarch64/Makefile
-+++ b/sysdeps/aarch64/Makefile
-@@ -41,7 +41,7 @@ endif
- ifeq ($(subdir),misc)
- sysdep_headers += sys/ifunc.h
- sysdep_routines += __mtag_address_get_tag \
-- __mtag_memset_tag \
-+ __mtag_tag_zero_region \
- __mtag_new_tag \
- __mtag_tag_region
-
-diff --git a/sysdeps/aarch64/__mtag_memset_tag.S b/sysdeps/aarch64/__mtag_tag_zero_region.S
-similarity index 82%
-rename from sysdeps/aarch64/__mtag_memset_tag.S
-rename to sysdeps/aarch64/__mtag_tag_zero_region.S
-index 3c202888a4..74d398bba5 100644
---- a/sysdeps/aarch64/__mtag_memset_tag.S
-+++ b/sysdeps/aarch64/__mtag_tag_zero_region.S
-@@ -20,9 +20,6 @@
-
- #ifdef USE_MTAG
-
--/* Use the same register names and assignments as memset. */
--#include "memset-reg.h"
--
- .arch armv8.5-a
- .arch_extension memtag
-
-@@ -31,16 +28,15 @@
- /* FIXME: This is a minimal implementation. We could do much better than
- this for large values of COUNT. */
-
--ENTRY(__libc_mtag_memset_with_tag)
-+#define dstin x0
-+#define count x1
-+#define dst x2
-
-- and valw, valw, 255
-- orr valw, valw, valw, lsl 8
-- orr valw, valw, valw, lsl 16
-- orr val, val, val, lsl 32
-- mov dst, dstin
-+ENTRY(__libc_mtag_tag_zero_region)
-
-+ mov dst, dstin
- L(loop):
-- stgp val, val, [dst], #16
-+ stzg dst, [dst], #16
- subs count, count, 16
- bne L(loop)
- #if 0
-@@ -49,5 +45,5 @@ L(loop):
- ldg dstin, [dstin] // Recover the tag created (might be untagged).
- #endif
- ret
--END (__libc_mtag_memset_with_tag)
-+END (__libc_mtag_tag_zero_region)
- #endif /* USE_MTAG */
-diff --git a/sysdeps/aarch64/libc-mtag.h b/sysdeps/aarch64/libc-mtag.h
-index 979cbb743e..f58402ccf9 100644
---- a/sysdeps/aarch64/libc-mtag.h
-+++ b/sysdeps/aarch64/libc-mtag.h
-@@ -39,8 +39,8 @@
- void *__libc_mtag_tag_region (const void *, size_t) */
- void *__libc_mtag_tag_region (void *, size_t);
-
--/* Optimized equivalent to __libc_mtag_tag_region followed by memset. */
--void *__libc_mtag_memset_with_tag (void *, int, size_t);
-+/* Optimized equivalent to __libc_mtag_tag_region followed by memset to 0. */
-+void *__libc_mtag_tag_zero_region (void *, size_t);
-
- /* Convert address P to a pointer that is tagged correctly for that
- location.
-diff --git a/sysdeps/generic/libc-mtag.h b/sysdeps/generic/libc-mtag.h
-index e8fc236b6c..4743e873f1 100644
---- a/sysdeps/generic/libc-mtag.h
-+++ b/sysdeps/generic/libc-mtag.h
-@@ -44,12 +44,12 @@ __libc_mtag_tag_region (void *p, size_t n)
- return p;
- }
-
--/* Optimized equivalent to __libc_mtag_tag_region followed by memset. */
-+/* Optimized equivalent to __libc_mtag_tag_region followed by memset to 0. */
- static inline void *
--__libc_mtag_memset_with_tag (void *p, int c, size_t n)
-+__libc_mtag_tag_zero_region (void *p, size_t n)
- {
- __libc_mtag_link_error ();
-- return memset (p, c, n);
-+ return memset (p, 0, n);
- }
-
- /* Convert address P to a pointer that is tagged correctly for that
---
-2.25.1
-
-
-From 4d596cb72342ba0734dc847653431e078a70edfc Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Tue, 16 Feb 2021 17:02:44 +0000
-Subject: [PATCH 09/11] malloc: Change calloc when tagging is disabled
-
-When glibc is built with memory tagging support (USE_MTAG) but it is not
-enabled at runtime (mtag_enabled) then unconditional memset was used
-even though that can be often avoided.
-
-This is for performance when tagging is supported but not enabled.
-The extra check should have no overhead: tag_new_zero_region already
-had a runtime check which the compiler can now optimize away.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/malloc.c | 10 ++++------
- 1 file changed, 4 insertions(+), 6 deletions(-)
-
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 01cf6e9325..0b2aff3768 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -3591,11 +3591,9 @@ __libc_calloc (size_t n, size_t elem_size)
- mchunkptr oldtop;
- INTERNAL_SIZE_T sz, oldtopsize;
- void *mem;
--#ifndef USE_MTAG
- unsigned long clearsize;
- unsigned long nclears;
- INTERNAL_SIZE_T *d;
--#endif
- ptrdiff_t bytes;
-
- if (__glibc_unlikely (__builtin_mul_overflow (n, elem_size, &bytes)))
-@@ -3674,12 +3672,13 @@ __libc_calloc (size_t n, size_t elem_size)
- return 0;
-
- mchunkptr p = mem2chunk (mem);
-+
- /* If we are using memory tagging, then we need to set the tags
- regardless of MORECORE_CLEARS, so we zero the whole block while
- doing so. */
--#ifdef USE_MTAG
-- return tag_new_zero_region (mem, CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
--#else
-+ if (__glibc_unlikely (mtag_enabled))
-+ return tag_new_zero_region (mem, CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ);
-+
- INTERNAL_SIZE_T csz = chunksize (p);
-
- /* Two optional cases in which clearing not necessary */
-@@ -3733,7 +3732,6 @@ __libc_calloc (size_t n, size_t elem_size)
- }
-
- return mem;
--#endif
- }
-
- /*
---
-2.25.1
-
-
-From 287a35fba55a0a817db7af71ee966a37b7642bf0 Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Mon, 8 Feb 2021 12:39:01 +0000
-Subject: [PATCH 10/11] malloc: Use branches instead of mtag_granule_mask
-
-The branches may be better optimized since mtag_enabled is widely used.
-
-Granule size larger than a chunk header is not supported since then we
-cannot have both the chunk header and user area granule aligned. To
-fix that for targets with large granule, the chunk layout has to change.
-
-So code that attempted to handle the granule mask generally was changed.
-This simplified CHUNK_AVAILABLE_SIZE and the logic in malloc_usable_size.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/arena.c | 1 -
- malloc/malloc.c | 34 ++++++++++++++--------------------
- 2 files changed, 14 insertions(+), 21 deletions(-)
-
-diff --git a/malloc/arena.c b/malloc/arena.c
-index 1e83bb66bd..9fbbb38a15 100644
---- a/malloc/arena.c
-+++ b/malloc/arena.c
-@@ -306,7 +306,6 @@ ptmalloc_init (void)
-
- mtag_enabled = true;
- mtag_mmap_flags = __MTAG_MMAP_FLAGS;
-- mtag_granule_mask = ~(size_t)(__MTAG_GRANULE_SIZE - 1);
- }
- #endif
-
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 0b2aff3768..849bd8e2c9 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -442,7 +442,6 @@ void *(*__morecore)(ptrdiff_t) = __default_morecore;
- #ifdef USE_MTAG
- static bool mtag_enabled = false;
- static int mtag_mmap_flags = 0;
--static size_t mtag_granule_mask = ~(size_t)0;
- #else
- # define mtag_enabled false
- # define mtag_mmap_flags 0
-@@ -1333,15 +1332,16 @@ nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- ((req) + SIZE_SZ + MALLOC_ALIGN_MASK) & ~MALLOC_ALIGN_MASK)
-
- /* Available size of chunk. This is the size of the real usable data
-- in the chunk, plus the chunk header. */
--#ifdef USE_MTAG
--#define CHUNK_AVAILABLE_SIZE(p) \
-- ((chunksize (p) + (chunk_is_mmapped (p) ? 0 : SIZE_SZ)) \
-- & mtag_granule_mask)
--#else
--#define CHUNK_AVAILABLE_SIZE(p) \
-- (chunksize (p) + (chunk_is_mmapped (p) ? 0 : SIZE_SZ))
--#endif
-+ in the chunk, plus the chunk header. Note: If memory tagging is
-+ enabled the layout changes to accomodate the granule size, this is
-+ wasteful for small allocations so not done by default. The logic
-+ does not work if chunk headers are not granule aligned. */
-+_Static_assert (__MTAG_GRANULE_SIZE <= CHUNK_HDR_SZ,
-+ "memory tagging is not supported with large granule.");
-+#define CHUNK_AVAILABLE_SIZE(p) \
-+ (__MTAG_GRANULE_SIZE > SIZE_SZ && __glibc_unlikely (mtag_enabled) ? \
-+ chunksize (p) : \
-+ chunksize (p) + (chunk_is_mmapped (p) ? 0 : SIZE_SZ))
-
- /* Check if REQ overflows when padded and aligned and if the resulting value
- is less than PTRDIFF_T. Returns TRUE and the requested size or MINSIZE in
-@@ -1353,7 +1353,6 @@ checked_request2size (size_t req, size_t *sz) __nonnull (1)
- if (__glibc_unlikely (req > PTRDIFF_MAX))
- return false;
-
--#ifdef USE_MTAG
- /* When using tagged memory, we cannot share the end of the user
- block with the header for the next chunk, so ensure that we
- allocate blocks that are rounded up to the granule size. Take
-@@ -1361,8 +1360,9 @@ checked_request2size (size_t req, size_t *sz) __nonnull (1)
- number. Ideally, this would be part of request2size(), but that
- must be a macro that produces a compile time constant if passed
- a constant literal. */
-- req = (req + ~mtag_granule_mask) & mtag_granule_mask;
--#endif
-+ if (__glibc_unlikely (mtag_enabled))
-+ req = (req + (__MTAG_GRANULE_SIZE - 1)) &
-+ ~(size_t)(__MTAG_GRANULE_SIZE - 1);
-
- *sz = request2size (req);
- return true;
-@@ -5112,14 +5112,8 @@ musable (void *mem)
- result = chunksize (p) - CHUNK_HDR_SZ;
- }
- else if (inuse (p))
-- result = chunksize (p) - SIZE_SZ;
-+ result = CHUNK_AVAILABLE_SIZE (p) - CHUNK_HDR_SZ;
-
--#ifdef USE_MTAG
-- /* The usable space may be reduced if memory tagging is needed,
-- since we cannot share the user-space data with malloc's internal
-- data structure. */
-- result &= mtag_granule_mask;
--#endif
- return result;
- }
- return 0;
---
-2.25.1
-
-
-From 66de173bf919e601e408dc78772c6841ad6388ab Mon Sep 17 00:00:00 2001
-From: Szabolcs Nagy <szabolcs.nagy@arm.com>
-Date: Wed, 17 Feb 2021 10:15:18 +0000
-Subject: [PATCH 11/11] malloc: Use mtag_enabled instead of USE_MTAG
-
-Use the runtime check where possible: it should not cause slow down in
-the !USE_MTAG case since then mtag_enabled is constant false, but it
-allows compiling the tagging logic so it's less likely to break or
-diverge when developers only test the !USE_MTAG case.
-
-Reviewed-by: DJ Delorie <dj@redhat.com>
----
- malloc/hooks.c | 10 ++++------
- malloc/malloc.c | 10 ++++------
- 2 files changed, 8 insertions(+), 12 deletions(-)
-
-diff --git a/malloc/hooks.c b/malloc/hooks.c
-index d8e304c31c..9474e199c3 100644
---- a/malloc/hooks.c
-+++ b/malloc/hooks.c
-@@ -262,11 +262,10 @@ free_check (void *mem, const void *caller)
-
- int err = errno;
-
--#ifdef USE_MTAG
- /* Quickly check that the freed pointer matches the tag for the memory.
- This gives a useful double-free detection. */
-- *(volatile char *)mem;
--#endif
-+ if (__glibc_unlikely (mtag_enabled))
-+ *(volatile char *)mem;
-
- __libc_lock_lock (main_arena.mutex);
- p = mem2chunk_check (mem, NULL);
-@@ -310,11 +309,10 @@ realloc_check (void *oldmem, size_t bytes, const void *caller)
- return NULL;
- }
-
--#ifdef USE_MTAG
- /* Quickly check that the freed pointer matches the tag for the memory.
- This gives a useful double-free detection. */
-- *(volatile char *)oldmem;
--#endif
-+ if (__glibc_unlikely (mtag_enabled))
-+ *(volatile char *)oldmem;
-
- __libc_lock_lock (main_arena.mutex);
- const mchunkptr oldp = mem2chunk_check (oldmem, &magic_p);
-diff --git a/malloc/malloc.c b/malloc/malloc.c
-index 849bd8e2c9..36583120ce 100644
---- a/malloc/malloc.c
-+++ b/malloc/malloc.c
-@@ -3286,11 +3286,10 @@ __libc_free (void *mem)
- if (mem == 0) /* free(0) has no effect */
- return;
-
--#ifdef USE_MTAG
- /* Quickly check that the freed pointer matches the tag for the memory.
- This gives a useful double-free detection. */
-- *(volatile char *)mem;
--#endif
-+ if (__glibc_unlikely (mtag_enabled))
-+ *(volatile char *)mem;
-
- int err = errno;
-
-@@ -3352,11 +3351,10 @@ __libc_realloc (void *oldmem, size_t bytes)
- if (oldmem == 0)
- return __libc_malloc (bytes);
-
--#ifdef USE_MTAG
- /* Perform a quick check to ensure that the pointer's tag matches the
- memory's tag. */
-- *(volatile char*) oldmem;
--#endif
-+ if (__glibc_unlikely (mtag_enabled))
-+ *(volatile char*) oldmem;
-
- /* chunk corresponding to oldmem */
- const mchunkptr oldp = mem2chunk (oldmem);
---
-2.25.1
-
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-04-26 01:14:54 +0000