[PATCH 5.19 0819/1157] mm: percpu: use kmemleak_ignore_phys() instead of kmemleak_free()

Greg Kroah-Hartman
2022-08-16T00:24:19Z

From: Patrick Wang <patrick.wang.shcn@gmail.com>

[ Upstream commit a317ebccaa3609917a2c021af870cf3fa607ab0c ]

Kmemleak recently added a rbtree to store the objects allocted with
physical address. Those objects can't be freed with kmemleak_free().

According to the comments, percpu allocations are tracked by kmemleak
separately. Kmemleak_free() was used to avoid the unnecessary
tracking. If kmemleak_free() fails, those objects would be scanned by
kmemleak, which is unnecessary but shouldn't lead to other effects.

Use kmemleak_ignore_phys() instead of kmemleak_free() for those
objects.

Link: https://lkml.kernel.org/r/20220705113158.127600-1-patrick.wang.shcn@gmail.com
Fixes: 0c24e061196c ("mm: kmemleak: add rbtree and store physical address for objects allocated with PA")
Signed-off-by: Patrick Wang <patrick.wang.shcn@gmail.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
mm/percpu.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/mm/percpu.c b/mm/percpu.c
index 3633eeefaa0d..27697b2429c2 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -3104,7 +3104,7 @@ int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
goto out_free_areas;
}
/* kmemleak tracks the percpu allocations separately */
- kmemleak_free(ptr);
+ kmemleak_ignore_phys(__pa(ptr));
areas[group] = ptr;

base = min(ptr, base);
@@ -3304,7 +3304,7 @@ int __init pcpu_page_first_chunk(size_t reserved_size, pcpu_fc_cpu_to_node_fn_t
goto enomem;
}
/* kmemleak tracks the percpu allocations separately */
- kmemleak_free(ptr);
+ kmemleak_ignore_phys(__pa(ptr));
pages[j++] = virt_to_page(ptr);
}
}
@@ -3417,7 +3417,7 @@ void __init setup_per_cpu_areas(void)
if (!ai || !fc)
panic("Failed to allocate memory for percpu areas.");
/* kmemleak tracks the percpu allocations separately */
- kmemleak_free(fc);
+ kmemleak_ignore_phys(__pa(fc));

ai->dyn_size = unit_size;
ai->unit_size = unit_size;
--
2.35.1