linux-kernel - Re: [RFT] Port 0x80 I/O speed

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-next>] [day] [month] [year] [list]

Date:	Wed, 12 Dec 2007 14:20:16 +0100
From:	Rene Herman <rene.herman@...access.nl>
To:	"linux-os (Dick Johnson)" <linux-os@...logic.com>
CC:	Alejandro Riveira Fernández 
	<ariveira@...il.com>, Linux Kernel <linux-kernel@...r.kernel.org>,
	dpreed@...d.com, Alan Cox <alan@...rguk.ukuu.org.uk>, pavel@....cz,
	andi@...stfloor.org, rol@...917.net,
	Krzysztof Halasa <khc@...waw.pl>, david@...idnewall.com,
	hpa@...or.com, john@...ffel.org
Subject: Re: [RFT] Port 0x80 I/O speed

On 12-12-07 13:59, linux-os (Dick Johnson) wrote:

> On Tue, 11 Dec 2007, [utf-8] Alejandro Riveira Fern?ndez wrote:

>> On my AMD 3800 X2 (2000MHz) ULi M1697 2.6.24-rc5 i get:
>>
>> cycles: out 1844674407370808, in 1844674407369087
>>
>> It is not constant but variations are not significant afaics
>>
> 
> It looks as though this hardware does not have a port 0x80
> and its access is trapped by the hardware with a long time-out!
> This may be the reason when the _p was called "harmful" on this
> platform!
> 
> I'm not sure the "rules" for port access allow for this kind of
> behavior. This design may be defective, needing to be brought
> to the attention of the vendor. A decent vendor would update
> a FPGA and provide code to burn a new BIOS.

I'm afraid it's just the test that is "defective" as 64-bit code. For some 
reason "=A" doesn't mean edx:eax on amd64 even though it's a useful register 
pair to be able to name there as well. Didn't catch that being without amd64 
machines myself.

Oh well. gcc -m32 fixes it...

Rene.
--
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/