diff mbox series

[3/3] slub: Actually use 'message' in restore_bytes()

Message ID 20210520013539.3733631-4-swboyd@chromium.org (mailing list archive)
State New, archived
Headers show
Series slub: Print non-hashed pointers in slub debugging | expand

Commit Message

Stephen Boyd May 20, 2021, 1:35 a.m. UTC
The message argument isn't used here. Let's pass the string to the
printk message so that the developer can figure out what's happening,
instead of guessing that a redzone is being restored, etc.

Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---
 mm/slub.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Vlastimil Babka May 20, 2021, 10:02 a.m. UTC | #1
On 5/20/21 3:35 AM, Stephen Boyd wrote:
> The message argument isn't used here. Let's pass the string to the
> printk message so that the developer can figure out what's happening,
> instead of guessing that a redzone is being restored, etc.
> 
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>

Reviewed-by: Vlastimil Babka <vbabka@suse.cz>

> ---
>  mm/slub.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/mm/slub.c b/mm/slub.c
> index 87eeeed1f369..16e8e8f8dc0c 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -777,7 +777,7 @@ static void init_object(struct kmem_cache *s, void *object, u8 val)
>  static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
>  						void *from, void *to)
>  {
> -	slab_fix(s, "Restoring 0x%px-0x%px=0x%x\n", from, to - 1, data);
> +	slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x\n", message, from, to - 1, data);
>  	memset(from, data, to - from);
>  }
>  
>
David Rientjes May 24, 2021, 5:12 a.m. UTC | #2
On Wed, 19 May 2021, Stephen Boyd wrote:

> The message argument isn't used here. Let's pass the string to the
> printk message so that the developer can figure out what's happening,
> instead of guessing that a redzone is being restored, etc.
> 
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>

Acked-by: David Rientjes <rientjes@google.com>
Joe Perches May 25, 2021, 7:37 a.m. UTC | #3
On Sun, 2021-05-23 at 22:12 -0700, David Rientjes wrote:
> On Wed, 19 May 2021, Stephen Boyd wrote:
> 
> > The message argument isn't used here. Let's pass the string to the
> > printk message so that the developer can figure out what's happening,
> > instead of guessing that a redzone is being restored, etc.
> > 
> > Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> 
> Acked-by: David Rientjes <rientjes@google.com>

Ideally, the slab_fix function would be marked with __printf and the
format here would not use \n as that's emitted by the slab_fix.
---
 mm/slub.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/mm/slub.c b/mm/slub.c
index ee51857d8e9bc..46f9b043089b6 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -702,6 +702,7 @@ static void slab_bug(struct kmem_cache *s, char *fmt, ...)
 	va_end(args);
 }
 
+__printf(2, 3)
 static void slab_fix(struct kmem_cache *s, char *fmt, ...)
 {
 	struct va_format vaf;
@@ -816,7 +817,8 @@ static void init_object(struct kmem_cache *s, void *object, u8 val)
 static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
 						void *from, void *to)
 {
-	slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x\n", message, from, to - 1, data);
+	slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x",
+		 message, from, to - 1, data);
 	memset(from, data, to - from);
 }
 
@@ -1069,13 +1071,13 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
 		slab_err(s, page, "Wrong number of objects. Found %d but should be %d",
 			 page->objects, max_objects);
 		page->objects = max_objects;
-		slab_fix(s, "Number of objects adjusted.");
+		slab_fix(s, "Number of objects adjusted");
 	}
 	if (page->inuse != page->objects - nr) {
 		slab_err(s, page, "Wrong object count. Counter is %d but counted were %d",
 			 page->inuse, page->objects - nr);
 		page->inuse = page->objects - nr;
-		slab_fix(s, "Object count adjusted.");
+		slab_fix(s, "Object count adjusted");
 	}
 	return search == NULL;
 }
Stephen Boyd May 26, 2021, 2:32 a.m. UTC | #4
Quoting Joe Perches (2021-05-25 00:37:45)
> On Sun, 2021-05-23 at 22:12 -0700, David Rientjes wrote:
> > On Wed, 19 May 2021, Stephen Boyd wrote:
> >
> > > The message argument isn't used here. Let's pass the string to the
> > > printk message so that the developer can figure out what's happening,
> > > instead of guessing that a redzone is being restored, etc.
> > >
> > > Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> >
> > Acked-by: David Rientjes <rientjes@google.com>
>
> Ideally, the slab_fix function would be marked with __printf and the
> format here would not use \n as that's emitted by the slab_fix.

Thanks. I can make this into a proper patch and author it from you. Can
you provide a signed-off-by? The restore_bytes() hunk is slightly
different but I can fix that up.

> ---
>  mm/slub.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
>
> diff --git a/mm/slub.c b/mm/slub.c
> index ee51857d8e9bc..46f9b043089b6 100644
> --- a/mm/slub.c
> +++ b/mm/slub.c
> @@ -702,6 +702,7 @@ static void slab_bug(struct kmem_cache *s, char *fmt, ...)
>         va_end(args);
>  }
>
> +__printf(2, 3)
>  static void slab_fix(struct kmem_cache *s, char *fmt, ...)
>  {
>         struct va_format vaf;
> @@ -816,7 +817,8 @@ static void init_object(struct kmem_cache *s, void *object, u8 val)
>  static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
>                                                 void *from, void *to)
>  {
> -       slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x\n", message, from, to - 1, data);
> +       slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x",
> +                message, from, to - 1, data);
>         memset(from, data, to - from);
>  }
>
> @@ -1069,13 +1071,13 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
>                 slab_err(s, page, "Wrong number of objects. Found %d but should be %d",
>                          page->objects, max_objects);
>                 page->objects = max_objects;
> -               slab_fix(s, "Number of objects adjusted.");
> +               slab_fix(s, "Number of objects adjusted");
>         }
>         if (page->inuse != page->objects - nr) {
>                 slab_err(s, page, "Wrong object count. Counter is %d but counted were %d",
>                          page->inuse, page->objects - nr);
>                 page->inuse = page->objects - nr;
> -               slab_fix(s, "Object count adjusted.");
> +               slab_fix(s, "Object count adjusted");
>         }
>         return search == NULL;
>  }
>
>
Joe Perches May 26, 2021, 2:38 a.m. UTC | #5
On Tue, 2021-05-25 at 22:32 -0400, Stephen Boyd wrote:
> Quoting Joe Perches (2021-05-25 00:37:45)
> > On Sun, 2021-05-23 at 22:12 -0700, David Rientjes wrote:
> > > On Wed, 19 May 2021, Stephen Boyd wrote:
> > > 
> > > > The message argument isn't used here. Let's pass the string to the
> > > > printk message so that the developer can figure out what's happening,
> > > > instead of guessing that a redzone is being restored, etc.
> > > > 
> > > > Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> > > 
> > > Acked-by: David Rientjes <rientjes@google.com>
> > 
> > Ideally, the slab_fix function would be marked with __printf and the
> > format here would not use \n as that's emitted by the slab_fix.
> 
> Thanks. I can make this into a proper patch and author it from you. Can
> you provide a signed-off-by? The restore_bytes() hunk is slightly
> different but I can fix that up.

If you want...

Signed-off-by: Joe Perches <joe@perches.com>

> 
> > ---
> >  mm/slub.c | 8 +++++---
> >  1 file changed, 5 insertions(+), 3 deletions(-)
> > 
> > diff --git a/mm/slub.c b/mm/slub.c
> > index ee51857d8e9bc..46f9b043089b6 100644
> > --- a/mm/slub.c
> > +++ b/mm/slub.c
> > @@ -702,6 +702,7 @@ static void slab_bug(struct kmem_cache *s, char *fmt, ...)
> >         va_end(args);
> >  }
> > 
> > +__printf(2, 3)
> >  static void slab_fix(struct kmem_cache *s, char *fmt, ...)
> >  {
> >         struct va_format vaf;
> > @@ -816,7 +817,8 @@ static void init_object(struct kmem_cache *s, void *object, u8 val)
> >  static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
> >                                                 void *from, void *to)
> >  {
> > -       slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x\n", message, from, to - 1, data);
> > +       slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x",
> > +                message, from, to - 1, data);
> >         memset(from, data, to - from);
> >  }
> > 
> > @@ -1069,13 +1071,13 @@ static int on_freelist(struct kmem_cache *s, struct page *page, void *search)
> >                 slab_err(s, page, "Wrong number of objects. Found %d but should be %d",
> >                          page->objects, max_objects);
> >                 page->objects = max_objects;
> > -               slab_fix(s, "Number of objects adjusted.");
> > +               slab_fix(s, "Number of objects adjusted");
> >         }
> >         if (page->inuse != page->objects - nr) {
> >                 slab_err(s, page, "Wrong object count. Counter is %d but counted were %d",
> >                          page->inuse, page->objects - nr);
> >                 page->inuse = page->objects - nr;
> > -               slab_fix(s, "Object count adjusted.");
> > +               slab_fix(s, "Object count adjusted");
> >         }
> >         return search == NULL;
> >  }
> > 
> >
diff mbox series

Patch

diff --git a/mm/slub.c b/mm/slub.c
index 87eeeed1f369..16e8e8f8dc0c 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -777,7 +777,7 @@  static void init_object(struct kmem_cache *s, void *object, u8 val)
 static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
 						void *from, void *to)
 {
-	slab_fix(s, "Restoring 0x%px-0x%px=0x%x\n", from, to - 1, data);
+	slab_fix(s, "Restoring %s 0x%px-0x%px=0x%x\n", message, from, to - 1, data);
 	memset(from, data, to - from);
 }