On Wed, Mar 02, 2016 at 10:47:59AM +0800, MaJun wrote:
> From: Ma Jun <majun...@huawei.com>
>
> The spin_lock/unlock_irq interface is not safe when this function is called
> at some case which need irq disabled.
> For example:
> spin_lock_irqsave()
> |
> request_irq() --> proc_alloc_inum()
> |
> spin_unlock_irqrestore()
Do you even read your own patch?
> if (!ida_pre_get(&proc_inum_ida, GFP_KERNEL))
^^^^^^^^^^
This.
It can block. You *can't* call that under spin_lock_irqsave(). At all.
You also can't do request_irq() under a spinlock, no matter whether you
disable irqs or not - it also blocks. So does proc_mkdir(), for that
matter, and not only in proc_alloc_inum().
NAKed. Don't do it. request_irq() is not to be called under spinlocks,
with or without irqs disabled.
