Re: [Xen-devel] [PATCH v3 14/39] ARM: new VGIC: Add GICv2 world switch backend

[Julien Grall <julien.grall@xxxxxxx>]

Hi Andre,

On 03/22/2018 11:04 AM, Andre Przywara wrote:
> This is a "patch to the patch" mentioned above, to make it clear what
> changed:
> We now take the desc lock in vgic_v2_fold_lr_state() when we are dealing
> with a hardware IRQ. This is a bit complicated, because we have to obey
> the existing locking order, so do our infamous "drop-take-retake" dance.
> Also I print a message about using the new VGIC and fix that last
> remaining "u32" usage.
>
> Please note that I had to initialise "desc" to NULL because my compiler
> (GCC 5.3) is not smart enough to see that we only use it with irq->hw
> set and it's safe. Please let me know if it's me not being smart enough
> here instead ;-)
I would not be surprised that even recent compiler can't deal with that. 
It would require quite some work from the compiler to know that desc is 
only used when irq->hw.
I will comment the code on 3a.

Cheers,

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel