__add_memory_block() calls both put_device() and device_unregister() when
storing the memory block into the xarray. This is incorrect because xarray
doesn't take an additional reference and device_unregister() already calls
put_device().
Triggering the issue looks really unlikely and its only effect should be to
log a spurious warning about a ref counted issue.
Fixes: 4fb6eabf1037 ("drivers/base/memory.c: cache memory blocks in xarray to accelerate lookup")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxxx>
Reviewed-by: David Hildenbrand <david@xxxxxxxxxx>
---
v2: Update Changelog
Add 'unlikely' in the title
Add Acked/Reviewed-by tags
---
drivers/base/memory.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 7222ff9b5e05..084d67fd55cc 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -636,10 +636,9 @@ static int __add_memory_block(struct memory_block *memory)
}
ret = xa_err(xa_store(&memory_blocks, memory->dev.id, memory,
GFP_KERNEL));
- if (ret) {
- put_device(&memory->dev);
+ if (ret)
device_unregister(&memory->dev);
- }
+
return ret;
}
--
2.32.0
