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From: Bob Pearson <rpearsonhpe@gmail.com>
To: Jason Gunthorpe <jgg@nvidia.com>,
	Linus Walleij <linus.walleij@linaro.org>
Cc: Leon Romanovsky <leonro@nvidia.com>,
	Bernard Metzler <BMT@zurich.ibm.com>,
	linux-rdma@vger.kernel.org
Subject: Re: [PATCH] RDMA/rxe: Pass a pointer to virt_to_page()
Date: Wed, 29 Mar 2023 21:45:45 -0500	[thread overview]
Message-ID: <66639a8e-e8b8-64b4-5b04-dec357db86a8@gmail.com> (raw)
In-Reply-To: <ZCTGw3+9rYQAmlJS@nvidia.com>

On 3/29/23 18:16, Jason Gunthorpe wrote:
> On Wed, Mar 29, 2023 at 04:28:08PM +0200, Linus Walleij wrote:
> 
>> I'm a bit puzzled: could the above code (which exist in
>> three instances in the driver) even work as it is? Or is it not used?
>> Or is there some failover from DMA to something else that is constantly
>> happening?
> 
> The physical address dma type IB_MR_TYPE_DMA is rarely used and maybe
> nobody ever tested it, at least in a configuration where kva != pa
> 
> Then again, maybe I got it wrong and it is still a kva in this case
> because it is still ultimately DMA mapped when using IB_MR_TYPE_DMA?
> 
> Bob?
> 
> Jason

In the amd64 environment I use to dev and test there is no difference AFAIK.
I have to go on faith that other platforms work but have very little experience.

Bob

  reply	other threads:[~2023-03-30  2:45 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-03-24 10:32 [PATCH] RDMA/rxe: Pass a pointer to virt_to_page() Linus Walleij
2023-03-24 12:27 ` kernel test robot
2023-03-24 13:59 ` Jason Gunthorpe
2023-03-29 14:28   ` Linus Walleij
2023-03-29 20:17     ` Bob Pearson
2023-03-29 23:16     ` Jason Gunthorpe
2023-03-30  2:45       ` Bob Pearson [this message]
2023-03-30 12:06         ` Jason Gunthorpe
2023-03-30 15:19           ` Linus Walleij

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