From 8e0c4ab36c61c514a9c1caaf5707d1f55ab5f6df Mon Sep 17 00:00:00 2001 From: Patrick Wang Date: Sat, 11 Jun 2022 11:55:49 +0800 Subject: [PATCH] mm: kmemleak: add OBJECT_PHYS flag for objects allocated with physical address Add OBJECT_PHYS flag for object. This flag is used to identify the objects allocated with physical address. The create_object_phys() function is added as well to set that flag and is used by kmemleak_alloc_phys(). Link: https://lkml.kernel.org/r/20220611035551.1823303-3-patrick.wang.shcn@gmail.com Signed-off-by: Patrick Wang Suggested-by: Catalin Marinas Reviewed-by: Catalin Marinas Cc: Yee Lee Signed-off-by: Andrew Morton --- mm/kmemleak.c | 40 +++++++++++++++++++++++++++++++--------- 1 file changed, 31 insertions(+), 9 deletions(-) diff --git a/mm/kmemleak.c b/mm/kmemleak.c index 156eafa..d82d8db 100644 --- a/mm/kmemleak.c +++ b/mm/kmemleak.c @@ -172,6 +172,8 @@ struct kmemleak_object { #define OBJECT_NO_SCAN (1 << 2) /* flag set to fully scan the object when scan_area allocation failed */ #define OBJECT_FULL_SCAN (1 << 3) +/* flag set for object allocated with physical address */ +#define OBJECT_PHYS (1 << 4) #define HEX_PREFIX " " /* number of bytes to print per line; must be 16 or 32 */ @@ -574,8 +576,9 @@ static int __save_stack_trace(unsigned long *trace) * Create the metadata (struct kmemleak_object) corresponding to an allocated * memory block and add it to the object_list and object_tree_root. */ -static struct kmemleak_object *create_object(unsigned long ptr, size_t size, - int min_count, gfp_t gfp) +static struct kmemleak_object *__create_object(unsigned long ptr, size_t size, + int min_count, gfp_t gfp, + bool is_phys) { unsigned long flags; struct kmemleak_object *object, *parent; @@ -595,7 +598,7 @@ static struct kmemleak_object *create_object(unsigned long ptr, size_t size, INIT_HLIST_HEAD(&object->area_list); raw_spin_lock_init(&object->lock); atomic_set(&object->use_count, 1); - object->flags = OBJECT_ALLOCATED; + object->flags = OBJECT_ALLOCATED | (is_phys ? OBJECT_PHYS : 0); object->pointer = ptr; object->size = kfence_ksize((void *)ptr) ?: size; object->excess_ref = 0; @@ -662,6 +665,20 @@ out: return object; } +/* Create kmemleak object which allocated with virtual address. */ +static struct kmemleak_object *create_object(unsigned long ptr, size_t size, + int min_count, gfp_t gfp) +{ + return __create_object(ptr, size, min_count, gfp, false); +} + +/* Create kmemleak object which allocated with physical address. */ +static struct kmemleak_object *create_object_phys(unsigned long ptr, size_t size, + int min_count, gfp_t gfp) +{ + return __create_object(ptr, size, min_count, gfp, true); +} + /* * Mark the object as not allocated and schedule RCU freeing via put_object(). */ @@ -728,11 +745,11 @@ static void delete_object_part(unsigned long ptr, size_t size) start = object->pointer; end = object->pointer + object->size; if (ptr > start) - create_object(start, ptr - start, object->min_count, - GFP_KERNEL); + __create_object(start, ptr - start, object->min_count, + GFP_KERNEL, object->flags & OBJECT_PHYS); if (ptr + size < end) - create_object(ptr + size, end - ptr - size, object->min_count, - GFP_KERNEL); + __create_object(ptr + size, end - ptr - size, object->min_count, + GFP_KERNEL, object->flags & OBJECT_PHYS); __delete_object(object); } @@ -1129,9 +1146,14 @@ EXPORT_SYMBOL(kmemleak_no_scan); */ void __ref kmemleak_alloc_phys(phys_addr_t phys, size_t size, gfp_t gfp) { + pr_debug("%s(0x%pa, %zu)\n", __func__, &phys, size); + if (PHYS_PFN(phys) >= min_low_pfn && PHYS_PFN(phys) < max_low_pfn) - /* assume min_count 0 */ - kmemleak_alloc(__va(phys), size, 0, gfp); + /* + * Create object with OBJECT_PHYS flag and + * assume min_count 0. + */ + create_object_phys((unsigned long)__va(phys), size, 0, gfp); } EXPORT_SYMBOL(kmemleak_alloc_phys); -- 2.7.4