linux-kernel - Re: EFI Boot Stub Early Console

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]

Date:	Mon, 19 Mar 2012 16:03:09 +0000
From:	Matt Fleming <matt.fleming@...el.com>
To:	Alan Cox <alan@...rguk.ukuu.org.uk>
Cc:	Shea Levy <shea@...alevy.com>, "H. Peter Anvin" <hpa@...or.com>,
	linux-kernel@...r.kernel.org
Subject: Re: EFI Boot Stub Early Console

On Mon, 2012-03-19 at 15:56 +0000, Alan Cox wrote:
> > > any bootloader (including the bootstub) will call ExitBootServices() 
> > > before any printk'ing actually happens?? Or am I misunderstanding the 
> > > spec somehow? I suppose I could just try it and see what happens...
> > 
> > Oops. Good point, that isn't going to work.
> 
> Surely it works fine if you are using bootstub directly from EFI ?

Yeah, up until the point you call ExitBootServices(), which is very
early in the boot process. After that you can't rely on the validity of
the console pointers in the system table.

--
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/