From: Daniel Thompson <daniel.thompson@xxxxxxxxxx> Subject: mm/slub.c: trace free objects at KERN_INFO Currently when trace is enabled (e.g. slub_debug=T,kmalloc-128 ) the trace messages are mostly output at KERN_INFO. However the trace code also calls print_section() to hexdump the head of a free object. This is hard coded to use KERN_ERR, meaning the console is deluged with trace messages even if we've asked for quiet. Fix this the obvious way but adding a level parameter to print_section(), allowing calls from the trace code to use the same trace level as other trace messages. Link: http://lkml.kernel.org/r/20170113154850.518-1-daniel.thompson@xxxxxxxxxx Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx> Acked-by: Christoph Lameter <cl@xxxxxxxxx> Acked-by: David Rientjes <rientjes@xxxxxxxxxx> Cc: Pekka Enberg <penberg@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/slub.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff -puN mm/slub.c~slub-trace-free-objects-at-kern_info mm/slub.c --- a/mm/slub.c~slub-trace-free-objects-at-kern_info +++ a/mm/slub.c @@ -496,10 +496,11 @@ static inline int check_valid_pointer(st return 1; } -static void print_section(char *text, u8 *addr, unsigned int length) +static void print_section(char *level, char *text, u8 *addr, + unsigned int length) { metadata_access_enable(); - print_hex_dump(KERN_ERR, text, DUMP_PREFIX_ADDRESS, 16, 1, addr, + print_hex_dump(level, text, DUMP_PREFIX_ADDRESS, 16, 1, addr, length, 1); metadata_access_disable(); } @@ -636,14 +637,15 @@ static void print_trailer(struct kmem_ca p, p - addr, get_freepointer(s, p)); if (s->flags & SLAB_RED_ZONE) - print_section("Redzone ", p - s->red_left_pad, s->red_left_pad); + print_section(KERN_ERR, "Redzone ", p - s->red_left_pad, + s->red_left_pad); else if (p > addr + 16) - print_section("Bytes b4 ", p - 16, 16); + print_section(KERN_ERR, "Bytes b4 ", p - 16, 16); - print_section("Object ", p, min_t(unsigned long, s->object_size, - PAGE_SIZE)); + print_section(KERN_ERR, "Object ", p, + min_t(unsigned long, s->object_size, PAGE_SIZE)); if (s->flags & SLAB_RED_ZONE) - print_section("Redzone ", p + s->object_size, + print_section(KERN_ERR, "Redzone ", p + s->object_size, s->inuse - s->object_size); if (s->offset) @@ -658,7 +660,8 @@ static void print_trailer(struct kmem_ca if (off != size_from_object(s)) /* Beginning of the filler is the free pointer */ - print_section("Padding ", p + off, size_from_object(s) - off); + print_section(KERN_ERR, "Padding ", p + off, + size_from_object(s) - off); dump_stack(); } @@ -820,7 +823,7 @@ static int slab_pad_check(struct kmem_ca end--; slab_err(s, page, "Padding overwritten. 0x%p-0x%p", fault, end - 1); - print_section("Padding ", end - remainder, remainder); + print_section(KERN_ERR, "Padding ", end - remainder, remainder); restore_bytes(s, "slab padding", POISON_INUSE, end - remainder, end); return 0; @@ -973,7 +976,7 @@ static void trace(struct kmem_cache *s, page->freelist); if (!alloc) - print_section("Object ", (void *)object, + print_section(KERN_INFO, "Object ", (void *)object, s->object_size); dump_stack(); _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
