linux-kernel - Re: Does Itanium permit speculative stores?

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:	Tue, 26 Nov 2013 23:55:58 -0500
From:	Jon Masters <jonathan@...masters.org>
To:	paulmck@...ux.vnet.ibm.com
CC:	tony.luck@...el.com, peterz@...radead.org,
	linux-kernel@...r.kernel.org
Subject: Re: Does Itanium permit speculative stores?

On 11/11/2013 12:13 PM, Paul E. McKenney wrote:
> Hello, Tony,
> 
> Does Itanium permit speculative stores?  For example, on Itanium what are
> the permitted outcomes of the following litmus test, where both x and y
> are initially zero?
> 
> 	CPU 0				CPU 1
> 
> 	r1 = ACCESS_ONCE(x);		r2 = ACCESS_ONCE(y);
> 	if (r1)				if (r2)
> 		ACCESS_ONCE(y) = 1;		ACCESS_ONCE(x) = 1;
> 
> In particular, is the outcome (r1 == 1 && r2 == 1) possible on Itanium
> given this litmus test?
> 
> 							Thanx, Paul
> 
> --
> 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/
> 

Btw, I was reading through some UEFI docs and noticed a reference to "A
Formal Specification of Intel Itanium Processor Family Memory Ordering",
then remembered this thread. In case it's of use:

http://www.intel.com/design/itanium/downloads/251429.htm

Jon.

--
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/