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authorMike Rapoport2021-10-21 10:09:29 +0300
committerLinus Torvalds2021-10-21 18:30:49 -1000
commit658aafc8139c23a6a23f6f4d9a0c4c95476838d4 (patch)
tree4ef1a0cb67618f453b0cf065fe785f3e5c0fed1a /mm
parent6c9a54551977ddf2d6e22c21354b4fb88946f96e (diff)
memblock: exclude MEMBLOCK_NOMAP regions from kmemleak
Vladimir Zapolskiy reports: Commit a7259df76702 ("memblock: make memblock_find_in_range method private") invokes a kernel panic while running kmemleak on OF platforms with nomaped regions: Unable to handle kernel paging request at virtual address fff000021e00000 [...] scan_block+0x64/0x170 scan_gray_list+0xe8/0x17c kmemleak_scan+0x270/0x514 kmemleak_write+0x34c/0x4ac The memory allocated from memblock is registered with kmemleak, but if it is marked MEMBLOCK_NOMAP it won't have linear map entries so an attempt to scan such areas will fault. Ideally, memblock_mark_nomap() would inform kmemleak to ignore MEMBLOCK_NOMAP memory, but it can be called before kmemleak interfaces operating on physical addresses can use __va() conversion. Make sure that functions that mark allocated memory as MEMBLOCK_NOMAP take care of informing kmemleak to ignore such memory. Link: https://lore.kernel.org/all/8ade5174-b143-d621-8c8e-dc6a1898c6fb@linaro.org Link: https://lore.kernel.org/all/c30ff0a2-d196-c50d-22f0-bd50696b1205@quicinc.com Fixes: a7259df76702 ("memblock: make memblock_find_in_range method private") Reported-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Vladimir Zapolskiy <vladimir.zapolskiy@linaro.org> Tested-by: Qian Cai <quic_qiancai@quicinc.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r--mm/memblock.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/mm/memblock.c b/mm/memblock.c
index 103b052c016e..5096500b2647 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -932,6 +932,9 @@ int __init_memblock memblock_mark_mirror(phys_addr_t base, phys_addr_t size)
* covered by the memory map. The struct page representing NOMAP memory
* frames in the memory map will be PageReserved()
*
+ * Note: if the memory being marked %MEMBLOCK_NOMAP was allocated from
+ * memblock, the caller must inform kmemleak to ignore that memory
+ *
* Return: 0 on success, -errno on failure.
*/
int __init_memblock memblock_mark_nomap(phys_addr_t base, phys_addr_t size)