4 files changed, 40 insertions, 6 deletions

diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index 24d2e30f1b46..a6a7a1c83f54 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -99,13 +99,7 @@
  * as arm where pointers are 32-bit aligned but there are data types such as
  * u64 which require 64-bit alignment.
  */
-#if defined(ARCH_KMALLOC_MINALIGN)
 #define CRYPTO_MINALIGN ARCH_KMALLOC_MINALIGN
-#elif defined(ARCH_SLAB_MINALIGN)
-#define CRYPTO_MINALIGN ARCH_SLAB_MINALIGN
-#else
-#define CRYPTO_MINALIGN __alignof__(unsigned long long)
-#endif
 
 #define CRYPTO_MINALIGN_ATTR __attribute__ ((__aligned__(CRYPTO_MINALIGN)))
 
diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h
index ca6b2b317991..1812dac8c496 100644
--- a/include/linux/slab_def.h
+++ b/include/linux/slab_def.h
@@ -16,6 +16,30 @@
 #include <linux/compiler.h>
 #include <linux/kmemtrace.h>
 
+#ifndef ARCH_KMALLOC_MINALIGN
+/*
+ * Enforce a minimum alignment for the kmalloc caches.
+ * Usually, the kmalloc caches are cache_line_size() aligned, except when
+ * DEBUG and FORCED_DEBUG are enabled, then they are BYTES_PER_WORD aligned.
+ * Some archs want to perform DMA into kmalloc caches and need a guaranteed
+ * alignment larger than the alignment of a 64-bit integer.
+ * ARCH_KMALLOC_MINALIGN allows that.
+ * Note that increasing this value may disable some debug features.
+ */
+#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
+#endif
+
+#ifndef ARCH_SLAB_MINALIGN
+/*
+ * Enforce a minimum alignment for all caches.
+ * Intended for archs that get misalignment faults even for BYTES_PER_WORD
+ * aligned buffers. Includes ARCH_KMALLOC_MINALIGN.
+ * If possible: Do not enable this flag for CONFIG_DEBUG_SLAB, it disables
+ * some debug features.
+ */
+#define ARCH_SLAB_MINALIGN 0
+#endif
+
 /*
  * struct kmem_cache
  *
diff --git a/include/linux/slob_def.h b/include/linux/slob_def.h
index 0ec00b39d006..62667f72c2ef 100644
--- a/include/linux/slob_def.h
+++ b/include/linux/slob_def.h
@@ -1,6 +1,14 @@
 #ifndef __LINUX_SLOB_DEF_H
 #define __LINUX_SLOB_DEF_H
 
+#ifndef ARCH_KMALLOC_MINALIGN
+#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long)
+#endif
+
+#ifndef ARCH_SLAB_MINALIGN
+#define ARCH_SLAB_MINALIGN __alignof__(unsigned long)
+#endif
+
 void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
 
 static __always_inline void *kmem_cache_alloc(struct kmem_cache *cachep,
diff --git a/include/linux/slub_def.h b/include/linux/slub_def.h
index 0249d4175bac..55695c8d2f8a 100644
--- a/include/linux/slub_def.h
+++ b/include/linux/slub_def.h
@@ -116,6 +116,14 @@ struct kmem_cache {
 
 #define KMALLOC_SHIFT_LOW ilog2(KMALLOC_MIN_SIZE)
 
+#ifndef ARCH_KMALLOC_MINALIGN
+#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
+#endif
+
+#ifndef ARCH_SLAB_MINALIGN
+#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
+#endif
+
 /*
  * Maximum kmalloc object size handled by SLUB. Larger object allocations
  * are passed through to the page allocator. The page allocator "fastpath"