On Tue, 1 Apr 2025 01:40:19 +0900 Moon Yeounsu wrote:

On Tue, Dec 10, 2024 at 07:15:19PM -0800, Jakub Kicinski wrote:

quoted

On Mon,  9 Dec 2024 18:28:27 +0900 Moon Yeounsu wrote:  

quoted

+	unsigned long flags;
+
+	spin_lock_irqsave(&np->stats_lock, flags);  

I believe spin_lock_bh() is sufficient here, no need to save IRQ flags.
 

Anyway, base on what I have learned, I believe `spin_lock_irq()`
should be used in this context instead of `spin_lock_bh()`.

The reason is that the `get_stats()` function can be called from
an interrupt context (in the top-half).

If my understanding is correct, calling `spin_lock_bh()` in the
top-half may lead to a deadlock.

The calling sequence is as follows:
	1. `rio_interrupt()` (registered via `request_irq()`)
	2. `rio_error()`
	3. `get_stats()`

Makes sense, please document this in the commit message for v6.