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To:     Jann Horn <jannh@google.com>
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From:   Logan Gunthorpe <logang@deltatee.com>
Message-ID: <6a41d1f8-4be6-40d6-e30d-71abf70f4468@deltatee.com>
Date:   Fri, 29 Mar 2019 15:43:23 -0600
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Subject: Re: [PATCH] x86/calgary: fix bitcast type warnings
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On 2019-03-29 3:40 p.m., Jann Horn wrote:
> So what is the right thing to do in the context of
> arch/x86/kernel/pci-calgary_64.c? That code wants to perform MMIO with
> endianness conversion, and these accesses are always performed as
> MMIO. Using the non-atomic 64-bit I/O helpers for this would be kind
> of awkward, since the accesses would never actually be split...

Well, if you know you're only ever doing MMIO, you'd probably just want
to use readq() directly.

Logan