au1000_close() calls free_irq() while aup->lock is still held with
spin_lock_irqsave(). free_irq() can sleep because it takes the IRQ
descriptor request mutex, so it does not belong inside the close-time
spinlocked section.
This was found by our static analysis tool and then confirmed by manual
review of the in-tree au1000_close() .ndo_stop path. The reviewed path
keeps aup->lock held across the MAC reset, queue stop and
free_irq(dev->irq, dev).
A directed runtime validation kept that ndo_stop carrier and the same
free_irq(dev->irq, dev) operation under the driver lock. Lockdep reported
"BUG: sleeping function called from invalid context" and "Invalid wait
context" while free_irq() was taking desc->request_mutex, with
au1000_close() and free_irq() on the stack.
Drop aup->lock before freeing the IRQ. The protected close-time work still
stops the device and queue before IRQ teardown, but the sleepable IRQ core
path now runs outside the spinlocked section.
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260619151816.1144289-1-runyu.xiao@seu.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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