kernel.git/mm/damon, branch linux-5.19.y

mm/damon: validate if the pmd entry is present before accessing

2022-10-24T07:56:48Z

commit c8b9aff419303e4d4219b5ff64b1c7e062dee48e upstream. pmd_huge() is used to validate if the pmd entry is mapped by a huge page, also including the case of non-present (migration or hwpoisoned) pmd entry on arm64 or x86 architectures. This means that pmd_pfn() can not get the correct pfn number for a non-present pmd entry, which will cause damon_get_page() to get an incorrect page struct (also may be NULL by pfn_to_online_page()), making the access statistics incorrect. This means that the DAMON may make incorrect decision according to the incorrect statistics, for example, DAMON may can not reclaim cold page in time due to this cold page was regarded as accessed mistakenly if DAMOS_PAGEOUT operation is specified. Moreover it does not make sense that we still waste time to get the page of the non-present entry. Just treat it as not-accessed and skip it, which maintains consistency with non-present pte level entries. So add pmd entry present validation to fix the above issues. Link: https://lkml.kernel.org/r/58b1d1f5fbda7db49ca886d9ef6783e3dcbbbc98.1660805030.git.baolin.wang@linux.alibaba.com Fixes: 3f49584b262c ("mm/damon: implement primitives for the virtual memory address spaces") Signed-off-by: Baolin Wang Reviewed-by: SeongJae Park Reviewed-by: Muchun Song Cc: Mike Kravetz Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

damon/sysfs: fix possible memleak on damon_sysfs_add_target

2022-10-05T08:40:55Z

commit 1c8e2349f2d033f634d046063b704b2ca6c46972 upstream. When damon_sysfs_add_target couldn't find proper task, New allocated damon_target structure isn't registered yet, So, it's impossible to free new allocated one by damon_sysfs_destroy_targets. By calling damon_add_target as soon as allocating new target, Fix this possible memory leak. Link: https://lkml.kernel.org/r/20220926160611.48536-1-sj@kernel.org Fixes: a61ea561c871 ("mm/damon/sysfs: link DAMON for virtual address spaces monitoring") Signed-off-by: Levi Yun Signed-off-by: SeongJae Park Reviewed-by: SeongJae Park Cc: [5.17.x] Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

mm/damon/dbgfs: fix memory leak when using debugfs_lookup()

2022-10-05T08:40:44Z

commit 1552fd3ef7dbe07208b8ae84a0a6566adf7dfc9d upstream. When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. Fix this up by properly calling dput(). Link: https://lkml.kernel.org/r/20220902191149.112434-1-sj@kernel.org Fixes: 75c1c2b53c78b ("mm/damon/dbgfs: support multiple contexts") Signed-off-by: Greg Kroah-Hartman Signed-off-by: SeongJae Park Cc: Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

mm/damon/dbgfs: avoid duplicate context directory creation

2022-08-31T15:18:15Z

commit d26f60703606ab425eee9882b32a1781a8bed74d upstream. When user tries to create a DAMON context via the DAMON debugfs interface with a name of an already existing context, the context directory creation fails but a new context is created and added in the internal data structure, due to absence of the directory creation success check. As a result, memory could leak and DAMON cannot be turned on. An example test case is as below: # cd /sys/kernel/debug/damon/ # echo "off" > monitor_on # echo paddr > target_ids # echo "abc" > mk_context # echo "abc" > mk_context # echo $$ > abc/target_ids # echo "on" > monitor_on <<< fails Return value of 'debugfs_create_dir()' is expected to be ignored in general, but this is an exceptional case as DAMON feature is depending on the debugfs functionality and it has the potential duplicate name issue. This commit therefore fixes the issue by checking the directory creation failure and immediately return the error in the case. Link: https://lkml.kernel.org/r/20220821180853.2400-1-sj@kernel.org Fixes: 75c1c2b53c78 ("mm/damon/dbgfs: support multiple contexts") Signed-off-by: Badari Pulavarty Signed-off-by: SeongJae Park Cc: [ 5.15.x] Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

mm/damon/reclaim: fix potential memory leak in damon_reclaim_init()

2022-08-17T13:16:15Z

[ Upstream commit 188043c7f4f2bd662f2a55957d684fffa543e600 ] damon_reclaim_init() allocates a memory chunk for ctx with damon_new_ctx(). When damon_select_ops() fails, ctx is not released, which will lead to a memory leak. We should release the ctx with damon_destroy_ctx() when damon_select_ops() fails to fix the memory leak. Link: https://lkml.kernel.org/r/20220714063746.2343549-1-niejianglei2021@163.com Fixes: 4d69c3457821 ("mm/damon/reclaim: use damon_select_ops() instead of damon_{v,p}a_set_operations()") Signed-off-by: Jianglei Nie Reviewed-by: SeongJae Park Cc: Signed-off-by: Andrew Morton Signed-off-by: Sasha Levin

mm/damon: use set_huge_pte_at() to make huge pte old

2022-07-03T22:42:32Z

The huge_ptep_set_access_flags() can not make the huge pte old according to the discussion [1], that means we will always mornitor the young state of the hugetlb though we stopped accessing the hugetlb, as a result DAMON will get inaccurate accessing statistics. So changing to use set_huge_pte_at() to make the huge pte old to fix this issue. [1] https://lore.kernel.org/all/Yqy97gXI4Nqb7dYo@arm.com/ Link: https://lkml.kernel.org/r/1655692482-28797-1-git-send-email-baolin.wang@linux.alibaba.com Fixes: 49f4203aae06 ("mm/damon: add access checking for hugetlb pages") Signed-off-by: Baolin Wang Reviewed-by: SeongJae Park Acked-by: Mike Kravetz Reviewed-by: Muchun Song Cc: Signed-off-by: Andrew Morton

mm/damon/reclaim: schedule 'damon_reclaim_timer' only after 'system_wq' is initialized

2022-06-17T02:11:30Z

Commit 059342d1dd4e ("mm/damon/reclaim: fix the timer always stays active") made DAMON_RECLAIM's 'enabled' parameter store callback, 'enabled_store()', to schedule 'damon_reclaim_timer'. The scheduling uses 'system_wq', which is initialized in 'workqueue_init_early()'. As kernel parameters parsing function ('parse_args()') is called before 'workqueue_init_early()', 'enabled_store()' can be executed before 'workqueue_init_early()' and end up accessing the uninitialized 'system_wq'. As a result, the booting hang[1]. This commit fixes the issue by checking if the initialization is done before scheduling the timer. [1] https://lkml.kernel.org/20220604192222.1488-1-sj@kernel.org/ Link: https://lkml.kernel.org/r/20220604195051.1589-1-sj@kernel.org Fixes: 059342d1dd4e ("mm/damon/reclaim: fix the timer always stays active") Signed-off-by: SeongJae Park Reported-by: Greg White Cc: Hailong Tu Signed-off-by: Andrew Morton

mm: damon: use HPAGE_PMD_SIZE

2022-05-19T21:08:55Z

Use HPAGE_PMD_SIZE instead of open coding. Link: https://lkml.kernel.org/r/20220517145120.118523-1-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/reclaim: use resource_size function on resource object

2022-05-13T14:20:18Z

Fix the following coccicheck warnings: ./mm/damon/reclaim.c:241:30-33: WARNING: Suspicious code. resource_size is maybe missing with res. Link: https://lkml.kernel.org/r/20220507032512.129598-1-jiapeng.chong@linux.alibaba.com Signed-off-by: Jiapeng Chong Reported-by: Abaci Robot Reviewed-by: SeongJae Park Cc: "Boehme, Markus" Signed-off-by: Andrew Morton

mm/damon/reclaim: support online inputs update

2022-05-13T14:20:09Z

DAMON_RECLAIM reads the user input parameters only when it starts. To allow more efficient online tuning, this commit implements a new input parameter called 'commit_inputs'. Writing true to the parameter makes DAMON_RECLAIM reads the input parameters again. Link: https://lkml.kernel.org/r/20220429160606.127307-14-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton