]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
dmaengine: idxd: Fix refcount underflow on module unload
authorYi Sun <yi.sun@intel.com>
Tue, 29 Jul 2025 15:03:13 +0000 (23:03 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 19 Sep 2025 14:35:50 +0000 (16:35 +0200)
commitce81905bec91da585341fdfdbc8553607a3084c6
tree6bf4bb9075ff6f506cee365fe2609fb533580aa7
parentdd7a7e43269711d757fc260b0bbdf7138f75de11
dmaengine: idxd: Fix refcount underflow on module unload

[ Upstream commit b7cb9a034305d52222433fad10c3de10204f29e7 ]

A recent refactor introduced a misplaced put_device() call, resulting in a
reference count underflow during module unload.

There is no need to add additional put_device() calls for idxd groups,
engines, or workqueues. Although the commit claims: "Note, this also
fixes the missing put_device() for idxd groups, engines, and wqs."

It appears no such omission actually existed. The required cleanup is
already handled by the call chain:
idxd_unregister_devices() -> device_unregister() -> put_device()

Extend idxd_cleanup() to handle the remaining necessary cleanup and
remove idxd_cleanup_internals(), which duplicates deallocation logic
for idxd, engines, groups, and workqueues. Memory management is also
properly handled through the Linux device model.

Fixes: a409e919ca32 ("dmaengine: idxd: Refactor remove call with idxd_cleanup() helper")
Signed-off-by: Yi Sun <yi.sun@intel.com>
Tested-by: Shuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://lore.kernel.org/r/20250729150313.1934101-3-yi.sun@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/dma/idxd/init.c