Commit b7cb9a03 authored by Yi Sun's avatar Yi Sun Committed by Vinod Koul
Browse files

dmaengine: idxd: Fix refcount underflow on module unload 



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: a409e919 ("dmaengine: idxd: Refactor remove call with idxd_cleanup() helper")
Signed-off-by: default avatarYi Sun <yi.sun@intel.com>
Tested-by: default avatarShuai Xue <xueshuai@linux.alibaba.com>
Reviewed-by: default avatarDave Jiang <dave.jiang@intel.com>
Acked-by: default avatarVinicius Costa Gomes <vinicius.gomes@intel.com>

Link: https://lore.kernel.org/r/20250729150313.1934101-3-yi.sun@intel.com


Signed-off-by: default avatarVinod Koul <vkoul@kernel.org>
parent f41c5388

drivers/dma/idxd/init.c

+4 −1
Original line number Diff line number Diff line
@@ -1291,7 +1291,10 @@ static void idxd_remove(struct pci_dev *pdev) 
	device_unregister(idxd_confdev(idxd));

	idxd_shutdown(pdev);

	idxd_device_remove_debugfs(idxd);

	idxd_cleanup(idxd);

	perfmon_pmu_remove(idxd);

	idxd_cleanup_interrupts(idxd);

	if (device_pasid_enabled(idxd))

		idxd_disable_system_pasid(idxd);

	pci_iounmap(pdev, idxd->reg_base);

	put_device(idxd_confdev(idxd));

	pci_disable_device(pdev);