2014-11-05 15:12:33

by Andrey Ryabinin

[permalink] [raw]
Subject: [PATCH] mm: slub: fix format mismatches in slab_err() callers

Adding __printf(3, 4) to slab_err exposed following:

mm/slub.c: In function ‘check_slab’:
mm/slub.c:852:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
s->name, page->objects, maxobj);
^
mm/slub.c:852:4: warning: too many arguments for format [-Wformat-extra-args]
mm/slub.c:857:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
s->name, page->inuse, page->objects);
^
mm/slub.c:857:4: warning: too many arguments for format [-Wformat-extra-args]

mm/slub.c: In function ‘on_freelist’:
mm/slub.c:905:4: warning: format ‘%d’ expects argument of type ‘int’, but argument 5 has type ‘long unsigned int’ [-Wformat=]
"should be %d", page->objects, max_objects);

Signed-off-by: Andrey Ryabinin <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
---
mm/slub.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 80c170e..850a94a 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -849,12 +849,12 @@ static int check_slab(struct kmem_cache *s, struct page *page)
maxobj = order_objects(compound_order(page), s->size, s->reserved);
if (page->objects > maxobj) {
slab_err(s, page, "objects %u > max %u",
- s->name, page->objects, maxobj);
+ page->objects, maxobj);
return 0;
}
if (page->inuse > page->objects) {
slab_err(s, page, "inuse %u > max %u",
- s->name, page->inuse, page->objects);
+ page->inuse, page->objects);
return 0;
}
/* Slab_pad_check fixes things up after itself */
@@ -902,7 +902,7 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)

if (page->objects != max_objects) {
slab_err(s, page, "Wrong number of objects. Found %d but "
- "should be %d", page->objects, max_objects);
+ "should be %ld", page->objects, max_objects);
page->objects = max_objects;
slab_fix(s, "Number of objects adjusted.");
}
--
2.1.3


Subject: Re: [PATCH] mm: slub: fix format mismatches in slab_err() callers

On Wed, 5 Nov 2014, Andrey Ryabinin wrote:

> Adding __printf(3, 4) to slab_err exposed following:

Acked-by: Christoph Lameter <[email protected]>

2014-11-05 21:48:48

by David Rientjes

[permalink] [raw]
Subject: Re: [PATCH] mm: slub: fix format mismatches in slab_err() callers

On Wed, 5 Nov 2014, Andrey Ryabinin wrote:

> Adding __printf(3, 4) to slab_err exposed following:
>
> mm/slub.c: In function ‘check_slab’:
> mm/slub.c:852:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
> s->name, page->objects, maxobj);
> ^
> mm/slub.c:852:4: warning: too many arguments for format [-Wformat-extra-args]
> mm/slub.c:857:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
> s->name, page->inuse, page->objects);
> ^
> mm/slub.c:857:4: warning: too many arguments for format [-Wformat-extra-args]
>

Wow, that's an ancient issue, thanks for finding it.

> mm/slub.c: In function ‘on_freelist’:
> mm/slub.c:905:4: warning: format ‘%d’ expects argument of type ‘int’, but argument 5 has type ‘long unsigned int’ [-Wformat=]
> "should be %d", page->objects, max_objects);
>
> Signed-off-by: Andrey Ryabinin <[email protected]>
> Cc: Christoph Lameter <[email protected]>
> Cc: Pekka Enberg <[email protected]>
> Cc: David Rientjes <[email protected]>
> Cc: Joonsoo Kim <[email protected]>
> ---
> mm/slub.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/mm/slub.c b/mm/slub.c
> index 80c170e..850a94a 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -849,12 +849,12 @@ static int check_slab(struct kmem_cache *s, struct page *page)
> maxobj = order_objects(compound_order(page), s->size, s->reserved);
> if (page->objects > maxobj) {
> slab_err(s, page, "objects %u > max %u",
> - s->name, page->objects, maxobj);
> + page->objects, maxobj);
> return 0;
> }
> if (page->inuse > page->objects) {
> slab_err(s, page, "inuse %u > max %u",
> - s->name, page->inuse, page->objects);
> + page->inuse, page->objects);
> return 0;
> }
> /* Slab_pad_check fixes things up after itself */
> @@ -902,7 +902,7 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
>
> if (page->objects != max_objects) {
> slab_err(s, page, "Wrong number of objects. Found %d but "
> - "should be %d", page->objects, max_objects);
> + "should be %ld", page->objects, max_objects);
> page->objects = max_objects;
> slab_fix(s, "Number of objects adjusted.");
> }

Instead of this hunk, I think that max_objects should be declared as int
rather than unsigned long since that's what order_objects() returns and it
is being compared to page->objects which is also int.

2014-11-06 08:17:12

by Andrey Ryabinin

[permalink] [raw]
Subject: [PATCH v2] mm: slub: fix format mismatches in slab_err() callers

Adding __printf(3, 4) to slab_err exposed following:

mm/slub.c: In function ‘check_slab’:
mm/slub.c:852:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
s->name, page->objects, maxobj);
^
mm/slub.c:852:4: warning: too many arguments for format [-Wformat-extra-args]
mm/slub.c:857:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
s->name, page->inuse, page->objects);
^
mm/slub.c:857:4: warning: too many arguments for format [-Wformat-extra-args]

mm/slub.c: In function ‘on_freelist’:
mm/slub.c:905:4: warning: format ‘%d’ expects argument of type ‘int’, but argument 5 has type ‘long unsigned int’ [-Wformat=]
"should be %d", page->objects, max_objects);

Fix first two warnings by removing redundant s->name.
Fix the last by changing type of max_object from unsigned long to int.

Signed-off-by: Andrey Ryabinin <[email protected]>
Cc: Christoph Lameter <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: David Rientjes <[email protected]>
Cc: Joonsoo Kim <[email protected]>
---

Changes since v1:
- To fix the last warning change the type of max_objects instead of changing format string (David)
- Slightly update changelog

mm/slub.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index 80c170e..ed816f8 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -849,12 +849,12 @@ static int check_slab(struct kmem_cache *s, struct page *page)
maxobj = order_objects(compound_order(page), s->size, s->reserved);
if (page->objects > maxobj) {
slab_err(s, page, "objects %u > max %u",
- s->name, page->objects, maxobj);
+ page->objects, maxobj);
return 0;
}
if (page->inuse > page->objects) {
slab_err(s, page, "inuse %u > max %u",
- s->name, page->inuse, page->objects);
+ page->inuse, page->objects);
return 0;
}
/* Slab_pad_check fixes things up after itself */
@@ -871,7 +871,7 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
int nr = 0;
void *fp;
void *object = NULL;
- unsigned long max_objects;
+ int max_objects;

fp = page->freelist;
while (fp && nr <= page->objects) {
--
2.1.3

2014-11-06 21:59:27

by David Rientjes

[permalink] [raw]
Subject: Re: [PATCH v2] mm: slub: fix format mismatches in slab_err() callers

On Thu, 6 Nov 2014, Andrey Ryabinin wrote:

> Adding __printf(3, 4) to slab_err exposed following:
>
> mm/slub.c: In function ‘check_slab’:
> mm/slub.c:852:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
> s->name, page->objects, maxobj);
> ^
> mm/slub.c:852:4: warning: too many arguments for format [-Wformat-extra-args]
> mm/slub.c:857:4: warning: format ‘%u’ expects argument of type ‘unsigned int’, but argument 4 has type ‘const char *’ [-Wformat=]
> s->name, page->inuse, page->objects);
> ^
> mm/slub.c:857:4: warning: too many arguments for format [-Wformat-extra-args]
>
> mm/slub.c: In function ‘on_freelist’:
> mm/slub.c:905:4: warning: format ‘%d’ expects argument of type ‘int’, but argument 5 has type ‘long unsigned int’ [-Wformat=]
> "should be %d", page->objects, max_objects);
>
> Fix first two warnings by removing redundant s->name.
> Fix the last by changing type of max_object from unsigned long to int.
>
> Signed-off-by: Andrey Ryabinin <[email protected]>
> Cc: Christoph Lameter <[email protected]>
> Cc: Pekka Enberg <[email protected]>
> Cc: David Rientjes <[email protected]>
> Cc: Joonsoo Kim <[email protected]>

Acked-by: David Rientjes <[email protected]>