mm: kmemleak: avoid using __va() on addresses that don't have a lowmem mapping

Some of the kmemleak_*() callbacks in memblock, bootmem, CMA convert a
physical address to a virtual one using __va().  However, such physical
addresses may sometimes be located in highmem and using __va() is
incorrect, leading to inconsistent object tracking in kmemleak.

The following functions have been added to the kmemleak API and they take
a physical address as the object pointer.  They only perform the
corresponding action if the address has a lowmem mapping:

kmemleak_alloc_phys
kmemleak_free_part_phys
kmemleak_not_leak_phys
kmemleak_ignore_phys

The affected calling places have been updated to use the new kmemleak
API.

Link: http://lkml.kernel.org/r/1471531432-16503-1-git-send-email-catalin.marinas@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Catalin Marinas 2016-10-11 13:55:11 -07:00 коммит произвёл Linus Torvalds
Родитель 0549a3c02e
Коммит 9099daed9c
7 изменённых файлов: 83 добавлений и 9 удалений

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@ -162,6 +162,15 @@ See the include/linux/kmemleak.h header for the functions prototype.
- ``kmemleak_alloc_recursive`` - as kmemleak_alloc but checks the recursiveness
- ``kmemleak_free_recursive`` - as kmemleak_free but checks the recursiveness
The following functions take a physical address as the object pointer
and only perform the corresponding action if the address has a lowmem
mapping:
- ``kmemleak_alloc_phys``
- ``kmemleak_free_part_phys``
- ``kmemleak_not_leak_phys``
- ``kmemleak_ignore_phys``
Dealing with false positives/negatives
--------------------------------------

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@ -38,6 +38,11 @@ extern void kmemleak_not_leak(const void *ptr) __ref;
extern void kmemleak_ignore(const void *ptr) __ref;
extern void kmemleak_scan_area(const void *ptr, size_t size, gfp_t gfp) __ref;
extern void kmemleak_no_scan(const void *ptr) __ref;
extern void kmemleak_alloc_phys(phys_addr_t phys, size_t size, int min_count,
gfp_t gfp) __ref;
extern void kmemleak_free_part_phys(phys_addr_t phys, size_t size) __ref;
extern void kmemleak_not_leak_phys(phys_addr_t phys) __ref;
extern void kmemleak_ignore_phys(phys_addr_t phys) __ref;
static inline void kmemleak_alloc_recursive(const void *ptr, size_t size,
int min_count, unsigned long flags,
@ -106,6 +111,19 @@ static inline void kmemleak_erase(void **ptr)
static inline void kmemleak_no_scan(const void *ptr)
{
}
static inline void kmemleak_alloc_phys(phys_addr_t phys, size_t size,
int min_count, gfp_t gfp)
{
}
static inline void kmemleak_free_part_phys(phys_addr_t phys, size_t size)
{
}
static inline void kmemleak_not_leak_phys(phys_addr_t phys)
{
}
static inline void kmemleak_ignore_phys(phys_addr_t phys)
{
}
#endif /* CONFIG_DEBUG_KMEMLEAK */

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@ -155,7 +155,7 @@ void __init free_bootmem_late(unsigned long physaddr, unsigned long size)
{
unsigned long cursor, end;
kmemleak_free_part(__va(physaddr), size);
kmemleak_free_part_phys(physaddr, size);
cursor = PFN_UP(physaddr);
end = PFN_DOWN(physaddr + size);
@ -399,7 +399,7 @@ void __init free_bootmem_node(pg_data_t *pgdat, unsigned long physaddr,
{
unsigned long start, end;
kmemleak_free_part(__va(physaddr), size);
kmemleak_free_part_phys(physaddr, size);
start = PFN_UP(physaddr);
end = PFN_DOWN(physaddr + size);
@ -420,7 +420,7 @@ void __init free_bootmem(unsigned long physaddr, unsigned long size)
{
unsigned long start, end;
kmemleak_free_part(__va(physaddr), size);
kmemleak_free_part_phys(physaddr, size);
start = PFN_UP(physaddr);
end = PFN_DOWN(physaddr + size);

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@ -336,7 +336,7 @@ int __init cma_declare_contiguous(phys_addr_t base,
* kmemleak scans/reads tracked objects for pointers to other
* objects but this address isn't mapped and accessible
*/
kmemleak_ignore(phys_to_virt(addr));
kmemleak_ignore_phys(addr);
base = addr;
}

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@ -90,6 +90,8 @@
#include <linux/cache.h>
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/bootmem.h>
#include <linux/pfn.h>
#include <linux/mmzone.h>
#include <linux/slab.h>
#include <linux/thread_info.h>
@ -1121,6 +1123,51 @@ void __ref kmemleak_no_scan(const void *ptr)
}
EXPORT_SYMBOL(kmemleak_no_scan);
/**
* kmemleak_alloc_phys - similar to kmemleak_alloc but taking a physical
* address argument
*/
void __ref kmemleak_alloc_phys(phys_addr_t phys, size_t size, int min_count,
gfp_t gfp)
{
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn)
kmemleak_alloc(__va(phys), size, min_count, gfp);
}
EXPORT_SYMBOL(kmemleak_alloc_phys);
/**
* kmemleak_free_part_phys - similar to kmemleak_free_part but taking a
* physical address argument
*/
void __ref kmemleak_free_part_phys(phys_addr_t phys, size_t size)
{
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn)
kmemleak_free_part(__va(phys), size);
}
EXPORT_SYMBOL(kmemleak_free_part_phys);
/**
* kmemleak_not_leak_phys - similar to kmemleak_not_leak but taking a physical
* address argument
*/
void __ref kmemleak_not_leak_phys(phys_addr_t phys)
{
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn)
kmemleak_not_leak(__va(phys));
}
EXPORT_SYMBOL(kmemleak_not_leak_phys);
/**
* kmemleak_ignore_phys - similar to kmemleak_ignore but taking a physical
* address argument
*/
void __ref kmemleak_ignore_phys(phys_addr_t phys)
{
if (!IS_ENABLED(CONFIG_HIGHMEM) || PHYS_PFN(phys) < max_low_pfn)
kmemleak_ignore(__va(phys));
}
EXPORT_SYMBOL(kmemleak_ignore_phys);
/*
* Update an object's checksum and return true if it was modified.
*/

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@ -723,7 +723,7 @@ int __init_memblock memblock_free(phys_addr_t base, phys_addr_t size)
(unsigned long long)base + size - 1,
(void *)_RET_IP_);
kmemleak_free_part(__va(base), size);
kmemleak_free_part_phys(base, size);
return memblock_remove_range(&memblock.reserved, base, size);
}
@ -1152,7 +1152,7 @@ static phys_addr_t __init memblock_alloc_range_nid(phys_addr_t size,
* The min_count is set to 0 so that memblock allocations are
* never reported as leaks.
*/
kmemleak_alloc(__va(found), size, 0, 0);
kmemleak_alloc_phys(found, size, 0, 0);
return found;
}
return 0;
@ -1399,7 +1399,7 @@ void __init __memblock_free_early(phys_addr_t base, phys_addr_t size)
memblock_dbg("%s: [%#016llx-%#016llx] %pF\n",
__func__, (u64)base, (u64)base + size - 1,
(void *)_RET_IP_);
kmemleak_free_part(__va(base), size);
kmemleak_free_part_phys(base, size);
memblock_remove_range(&memblock.reserved, base, size);
}
@ -1419,7 +1419,7 @@ void __init __memblock_free_late(phys_addr_t base, phys_addr_t size)
memblock_dbg("%s: [%#016llx-%#016llx] %pF\n",
__func__, (u64)base, (u64)base + size - 1,
(void *)_RET_IP_);
kmemleak_free_part(__va(base), size);
kmemleak_free_part_phys(base, size);
cursor = PFN_UP(base);
end = PFN_DOWN(base + size);

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@ -84,7 +84,7 @@ void __init free_bootmem_late(unsigned long addr, unsigned long size)
{
unsigned long cursor, end;
kmemleak_free_part(__va(addr), size);
kmemleak_free_part_phys(addr, size);
cursor = PFN_UP(addr);
end = PFN_DOWN(addr + size);