Le jeu. 20 août 2020 à 20:23, Lars-Peter Clausen <l...@metafoo.de> a écrit :
On 8/20/20 1:59 PM, Paul Cercueil wrote:
Hi,

Le dim. 16 août 2020 à 12:52, madhuparnabhowmi...@gmail.com a écrit :
From: Madhuparna Bhowmik <madhuparnabhowmi...@gmail.com>

In probe IRQ is requested before zchan->id is initialized which can be read in the irq handler. Hence, shift request irq and enable clock after other initializations complete. Here, enable clock part is not part of the race, it is just shifted down after request_irq to keep the error
path same as before.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmi...@gmail.com>

I don't think there is a race at all, the interrupt handler won't be called before the DMA is registered.

From a purely formal verification perspective there is a bug. The interrupt could fire if i.e. the hardware is buggy or something. In general it is a good idea to not request the IRQ until all the resources that are used in the interrupt handler are properly set up. Even if you know that in practice the interrupt will never fire this early.


Fair enough, I'm fine with that, but the patch should be reworked so that the clk_prepare_enable() call is not moved.

Cheers,
-Paul


Reply via email to