linux-kernel - Re: [PATCH -mm 0/3] i386 boot: replace boot_ioremap with enhanced bt

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <478CB75B.70503@zytor.com>
Date:	Tue, 15 Jan 2008 08:38:35 -0500
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Ingo Molnar <mingo@...e.hu>
CC:	"Huang, Ying" <ying.huang@...el.com>,
	venkatesh.pallipadi@...el.com, akpm@...ux-foundation.org,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>, Andi Kleen <ak@...e.de>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH -mm 0/3] i386 boot: replace boot_ioremap with enhanced
 bt_ioremap

Ingo Molnar wrote:
> * H. Peter Anvin <hpa@...or.com> wrote:
> 
>> I did a quick scan over the patchset (not quite awake yet, so I may 
>> very well have missed something), but it looks like EFI (again!) is 
>> the only user of ioremapping before paging_init().  This makes me 
>> wonder if that code can't be restructured so that isn't necessary.
> 
> i think that in general making access to unmapped memory a bit easier is 
> generally a good robustness idea as ACPI could be impacted by it as 
> well.
> 
> Fundamentally, paging_init() has obvious dependency on "figuring out the 
> memory setup" of the box, and "figuring out the memory setup" means 
> interpreting various data structures passed in by the BIOS - some of 
> which might be in not yet mapped areas or iommu areas (if we have to do 
> some early quirk). So having a robust implementation of ioremap_early() 
> sounds like a definitive plus.
> 

Fair enough.  If it's generally useful, I certainly have no objections.

	-hpa
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/