]> www.infradead.org Git - users/hch/misc.git/commitdiff
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)
committerVinod Koul <vkoul@kernel.org>
Wed, 20 Aug 2025 17:29:58 +0000 (22:59 +0530)
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>
drivers/dma/idxd/init.c

index 487268fc527b0c84935a32177514d51efe4db388..efe614a528faf3656dde19735c2166a52138f6f7 100644 (file)
@@ -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);