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>

3 files changed, 0 insertions, 12 deletions

diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c
index 7b62df86be1d..11ad089f2c74 100644
--- a/kernel/bpf/core.c
+++ b/kernel/bpf/core.c
@@ -85,8 +85,6 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
 	if (fp == NULL)
 		return NULL;
 
-	kmemcheck_annotate_bitfield(fp, meta);
-
 	aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
 	if (aux == NULL) {
 		vfree(fp);
@@ -127,8 +125,6 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
 	if (fp == NULL) {
 		__bpf_prog_uncharge(fp_old->aux->user, delta);
 	} else {
-		kmemcheck_annotate_bitfield(fp, meta);
-
 		memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
 		fp->pages = pages;
 		fp->aux->prog = fp;
@@ -662,8 +658,6 @@ static struct bpf_prog *bpf_prog_clone_create(struct bpf_prog *fp_other,
 
 	fp = __vmalloc(fp_other->pages * PAGE_SIZE, gfp_flags, PAGE_KERNEL);
 	if (fp != NULL) {
-		kmemcheck_annotate_bitfield(fp, meta);
-
 		/* aux->prog still points to the fp_other one, so
 		 * when promoting the clone to the real program,
 		 * this still needs to be adapted.
diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
index db933d063bfc..9776da8db180 100644
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -47,7 +47,6 @@
 #include <linux/stringify.h>
 #include <linux/bitops.h>
 #include <linux/gfp.h>
-#include <linux/kmemcheck.h>
 #include <linux/random.h>
 #include <linux/jhash.h>
 
@@ -3238,8 +3237,6 @@ static void __lockdep_init_map(struct lockdep_map *lock, const char *name,
 {
 	int i;
 
-	kmemcheck_mark_initialized(lock, sizeof(*lock));
-
 	for (i = 0; i < NR_LOCKDEP_CACHING_CLASSES; i++)
 		lock->class_cache[i] = NULL;
 
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 845f3805c73d..d57fede84b38 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -13,7 +13,6 @@
 #include <linux/uaccess.h>
 #include <linux/hardirq.h>
 #include <linux/kthread.h>	/* for self test */
-#include <linux/kmemcheck.h>
 #include <linux/module.h>
 #include <linux/percpu.h>
 #include <linux/mutex.h>
@@ -2055,7 +2054,6 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
 	}
 
 	event = __rb_page_index(tail_page, tail);
-	kmemcheck_annotate_bitfield(event, bitfield);
 
 	/* account for padding bytes */
 	local_add(BUF_PAGE_SIZE - tail, &cpu_buffer->entries_bytes);
@@ -2686,7 +2684,6 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
 	/* We reserved something on the buffer */
 
 	event = __rb_page_index(tail_page, tail);
-	kmemcheck_annotate_bitfield(event, bitfield);
 	rb_update_event(cpu_buffer, event, info);
 
 	local_inc(&tail_page->entries);