linux-kernel - Re: [PATCH v2 1/3] x86, boot: add mmio serial during compressed boot

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: <51E169F1.5010301@zytor.com>
Date:	Sat, 13 Jul 2013 07:53:37 -0700
From:	"H. Peter Anvin" <hpa@...or.com>
To:	Yinghai Lu <yinghai@...nel.org>
CC:	Kees Cook <keescook@...omium.org>,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Rob Landley <rob@...dley.net>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	the arch/x86 maintainers <x86@...nel.org>,
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	linux-doc@...r.kernel.org, linux-serial@...r.kernel.org
Subject: Re: [PATCH v2 1/3] x86, boot: add mmio serial during compressed boot

On 07/12/2013 11:47 PM, Yinghai Lu wrote:
> 
> for 32 bit, that is ok.
> for 64 bit via 32bit bootloader, arch/x86/boot/compressed/head_64.S
> will set page table for first 4G still ok.
> for 64 bit via 64bit loader, like kexec via bzImage64, First Kernel/Kexec only
> set ident mapping for usable range, so mmio just under 64 is not mapped.
> 
> Looks like we need to update boot.txt to add requirement for 64bit bootloader
> that 0-4G need to be all ident mapping?
> 

I think that is an unrealistic requirement, especially if this is the
sole user.

	-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/