kmemcheck: remove annotations

Patch series "kmemcheck: kill kmemcheck", v2.

As discussed at LSF/MM, kill kmemcheck.

KASan is a replacement that is able to work without the limitation of
kmemcheck (single CPU, slow).  KASan is already upstream.

We are also not aware of any users of kmemcheck (or users who don't
consider KASan as a suitable replacement).

The only objection was that since KASAN wasn't supported by all GCC
versions provided by distros at that time we should hold off for 2
years, and try again.

Now that 2 years have passed, and all distros provide gcc that supports
KASAN, kill kmemcheck again for the very same reasons.

This patch (of 4):

Remove kmemcheck annotations, and calls to kmemcheck from the kernel.

[alexander.levin@verizon.com: correctly remove kmemcheck call from dma_map_sg_attrs]
  Link: http://lkml.kernel.org/r/20171012192151.26531-1-alexander.levin@verizon.com
Link: http://lkml.kernel.org/r/20171007030159.22241-2-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Hansen <devtimhansen@gmail.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

7 files changed, 1 insertions, 30 deletions

diff --git a/include/linux/c2port.h b/include/linux/c2port.h
index 4efabcb51347..f2736348ca26 100644
--- a/include/linux/c2port.h
+++ b/include/linux/c2port.h
@@ -9,8 +9,6 @@
  * the Free Software Foundation
  */
 
-#include <linux/kmemcheck.h>
-
 #define C2PORT_NAME_LEN			32
 
 struct device;
@@ -22,10 +20,8 @@ struct device;
 /* Main struct */
 struct c2port_ops;
 struct c2port_device {
-	kmemcheck_bitfield_begin(flags);
 	unsigned int access:1;
 	unsigned int flash_access:1;
-	kmemcheck_bitfield_end(flags);
 
 	int id;
 	char name[C2PORT_NAME_LEN];
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index eee1499db396..e8f8e8fb244d 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -9,7 +9,6 @@
 #include <linux/dma-debug.h>
 #include <linux/dma-direction.h>
 #include <linux/scatterlist.h>
-#include <linux/kmemcheck.h>
 #include <linux/bug.h>
 #include <linux/mem_encrypt.h>
 
@@ -232,7 +231,6 @@ static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
 	const struct dma_map_ops *ops = get_dma_ops(dev);
 	dma_addr_t addr;
 
-	kmemcheck_mark_initialized(ptr, size);
 	BUG_ON(!valid_dma_direction(dir));
 	addr = ops->map_page(dev, virt_to_page(ptr),
 			     offset_in_page(ptr), size,
@@ -265,11 +263,8 @@ static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 				   unsigned long attrs)
 {
 	const struct dma_map_ops *ops = get_dma_ops(dev);
-	int i, ents;
-	struct scatterlist *s;
+	int ents;
 
-	for_each_sg(sg, s, nents, i)
-		kmemcheck_mark_initialized(sg_virt(s), s->length);
 	BUG_ON(!valid_dma_direction(dir));
 	ents = ops->map_sg(dev, sg, nents, dir, attrs);
 	BUG_ON(ents < 0);
@@ -299,7 +294,6 @@ static inline dma_addr_t dma_map_page_attrs(struct device *dev,
 	const struct dma_map_ops *ops = get_dma_ops(dev);
 	dma_addr_t addr;
 
-	kmemcheck_mark_initialized(page_address(page) + offset, size);
 	BUG_ON(!valid_dma_direction(dir));
 	addr = ops->map_page(dev, page, offset, size, dir, attrs);
 	debug_dma_map_page(dev, page, offset, size, dir, addr, false);
diff --git a/include/linux/filter.h b/include/linux/filter.h
index 48ec57e70f9f..42197b16dd78 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -454,13 +454,11 @@ struct bpf_binary_header {
 
 struct bpf_prog {
 	u16			pages;		/* Number of allocated pages */
-	kmemcheck_bitfield_begin(meta);
 	u16			jited:1,	/* Is our filter JIT'ed? */
 				locked:1,	/* Program image locked? */
 				gpl_compatible:1, /* Is filter GPL compatible? */
 				cb_access:1,	/* Is control block accessed? */
 				dst_needed:1;	/* Do we need dst entry? */
-	kmemcheck_bitfield_end(meta);
 	enum bpf_prog_type	type;		/* Type of BPF program */
 	u32			len;		/* Number of filter blocks */
 	u32			jited_len;	/* Size of jited insns in bytes */
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 09643e0472fc..cfd0ac4e5e0e 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -209,14 +209,6 @@ struct page {
 					   not kmapped, ie. highmem) */
 #endif /* WANT_PAGE_VIRTUAL */
 
-#ifdef CONFIG_KMEMCHECK
-	/*
-	 * kmemcheck wants to track the status of each byte in a page; this
-	 * is a pointer to such a status block. NULL if not tracked.
-	 */
-	void *shadow;
-#endif
-
 #ifdef LAST_CPUPID_NOT_IN_PAGE_FLAGS
 	int _last_cpupid;
 #endif
diff --git a/include/linux/net.h b/include/linux/net.h
index d97d80d7fdf8..caeb159abda5 100644
--- a/include/linux/net.h
+++ b/include/linux/net.h
@@ -22,7 +22,6 @@
 #include <linux/random.h>
 #include <linux/wait.h>
 #include <linux/fcntl.h>	/* For O_CLOEXEC and O_NONBLOCK */
-#include <linux/kmemcheck.h>
 #include <linux/rcupdate.h>
 #include <linux/once.h>
 #include <linux/fs.h>
@@ -111,9 +110,7 @@ struct socket_wq {
 struct socket {
 	socket_state		state;
 
-	kmemcheck_bitfield_begin(type);
 	short			type;
-	kmemcheck_bitfield_end(type);
 
 	unsigned long		flags;
 
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index fa6ace66fea5..289e4d54e3e0 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -2,7 +2,6 @@
 #ifndef _LINUX_RING_BUFFER_H
 #define _LINUX_RING_BUFFER_H
 
-#include <linux/kmemcheck.h>
 #include <linux/mm.h>
 #include <linux/seq_file.h>
 #include <linux/poll.h>
@@ -14,9 +13,7 @@ struct ring_buffer_iter;
  * Don't refer to this struct directly, use functions below.
  */
 struct ring_buffer_event {
-	kmemcheck_bitfield_begin(bitfield);
 	u32		type_len:5, time_delta:27;
-	kmemcheck_bitfield_end(bitfield);
 
 	u32		array[];
 };
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index d448a4804aea..aa1341474916 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -15,7 +15,6 @@
 #define _LINUX_SKBUFF_H
 
 #include <linux/kernel.h>
-#include <linux/kmemcheck.h>
 #include <linux/compiler.h>
 #include <linux/time.h>
 #include <linux/bug.h>
@@ -704,7 +703,6 @@ struct sk_buff {
 	/* Following fields are _not_ copied in __copy_skb_header()
 	 * Note that queue_mapping is here mostly to fill a hole.
 	 */
-	kmemcheck_bitfield_begin(flags1);
 	__u16			queue_mapping;
 
 /* if you move cloned around you also must adapt those constants */
@@ -723,7 +721,6 @@ struct sk_buff {
 				head_frag:1,
 				xmit_more:1,
 				__unused:1; /* one bit hole */
-	kmemcheck_bitfield_end(flags1);
 
 	/* fields enclosed in headers_start/headers_end are copied
 	 * using a single memcpy() in __copy_skb_header()