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From:   "Luck, Tony" <tony.luck@intel.com>
To:     Boris Brezillon <boris.brezillon@bootlin.com>,
        Arnd Bergmann <arnd@arndb.de>
CC:     Bjorn Helgaas <bhelgaas@google.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "jchandra@broadcom.com" <jchandra@broadcom.com>,
        Sinan Kaya <okaya@codeaurora.org>,
        Tomasz Nowicki <tn@semihalf.com>,
        Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
        "Miquel Raynal" <miquel.raynal@bootlin.com>
Subject: RE: how to fix acpi_pci_root_remap_iospace?
Thread-Topic: how to fix acpi_pci_root_remap_iospace?
Thread-Index: AdQ1ogY0Ns2AKmc+RseoCIXE9twQpAAPjfSA//+wrwCAARIPAIAAAlCAgAABJfA=
Date:   Fri, 17 Aug 2018 15:56:23 +0000
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        <20180816232639.GA25889@agluck-desk>
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>> - Some targets don't have any support for I/O space on their PCI bus and just
>>    want to get things to compile by setting PCI_IOBASE to zero, this still opens
>>     up some of the same problems as above, but doesn't really help otherwise.

That sounds horrible. Why would you want to have a driver that can't possibly
work on your platform compile cleanly? That's just asking for trouble. Sombody
might load that driver, and ... all the outb/outw/outl calls just corrupt low memory.

> Hm, maybe it's just easier to revert the patch since we got rid of
> patches adding COMPILE_TEST to drivers which were using read/writesl()
> (it turned out ia64 and sparc were not the only archs to not implement
> readsx/writesx() variants, and fixing them is not that easy).

That sounds like a better course of action.

-Tony