Re: Question Regarding ERMS memcpy

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From	Borislav Petkov <bp@suse.de>
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Subject	Re: Question Regarding ERMS memcpy
Date	Mon, 06 Mar 2017 15:10:04 +0100
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On Mon, Mar 06, 2017 at 05:41:22AM -0800, hpa@zytor.com wrote:
> It isn't really that straightforward IMO.
>
> For UC memory transaction size really needs to be specified explicitly
> at all times and should be part of the API, rather than implicit.
>
> For WC/WT/WB device memory, the ordinary memcpy is valid and
> preferred.

I'm practically partially reverting

6175ddf06b61 ("x86: Clean up mem*io functions.")

Are you saying, this was wrong before too?

Maybe it was wrong, strictly speaking, but maybe that was good enough
for our purposes...

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nürnberg)
--

Thread

Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-04 22:20 +0100
  Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-04 23:50 +0100
    Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-05 01:00 +0100
      Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 01:20 +0100
        Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-05 01:30 +0100
          Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 01:40 +0100
            Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-05 02:00 +0100
              Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 11:00 +0100
                Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 12:20 +0100
                Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 14:10 +0100
                Re: Question Regarding ERMS memcpy Linus Torvalds <torvalds@linux-foundation.org> - 2017-03-05 20:30 +0100
                Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 21:20 +0100
                Re: Question Regarding ERMS memcpy Linus Torvalds <torvalds@linux-foundation.org> - 2017-03-05 21:20 +0100
                Re: Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-06 08:10 +0100
                Re: Question Regarding ERMS memcpy "H. Peter Anvin" <hpa@zytor.com> - 2017-03-06 08:40 +0100
                Re: Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-06 18:50 +0100
                Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-06 20:10 +0100
                Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-06 14:40 +0100
                Re: Question Regarding ERMS memcpy hpa@zytor.com - 2017-03-06 14:50 +0100
                Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-06 15:10 +0100
            Re: Question Regarding ERMS memcpy Logan Gunthorpe <logang@deltatee.com> - 2017-03-05 06:00 +0100
              Re: Question Regarding ERMS memcpy Borislav Petkov <bp@suse.de> - 2017-03-05 11:00 +0100

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