RE: [PATCH v8 6/7] apei/ghes: Use unrcu_pointer for cmpxchg

From: Justin He
Date: Wed Oct 12 2022 - 00:35:36 EST




> -----Original Message-----
> From: Borislav Petkov <bp@xxxxxxxxx>
> Sent: Tuesday, October 11, 2022 10:46 PM
> To: Justin He <Justin.He@xxxxxxx>
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> Subject: Re: [PATCH v8 6/7] apei/ghes: Use unrcu_pointer for cmpxchg
>
> On Tue, Oct 11, 2022 at 02:32:48PM +0000, Justin He wrote:
> > My original purpose is to make it pass the sparse checking.
>
> Then do this pls.
>
> This is a combined diff - do a second patch which does only remove the
> smp_wmb(). The smp_wmb() there is not needed as the cmpxchg() already
> implies a smp_mb() so there's no need for that separate, explicit one.
>
> But it would be prudent to have it in a separate patch just in case.
>
Sure, I will insert/append your patch in my v9 series if there are no more comments.

Thanks for the