From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jes Sorensen Date: Mon, 03 Sep 2007 09:21:41 +0000 Subject: Re: [PATCH 1/1] Allow global purge traslation cache (ptc.g) to be disabled Message-Id: List-Id: References: <200708301338.34246.protasnb@gmail.com> In-Reply-To: <200708301338.34246.protasnb@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org >>>>> "Natalie" = Natalie Protasevich writes: Natalie> From: Natalie Protasevich Natalie> This patch allows to disable ptc.g. The code used to be in Natalie> the kernel, then was removed in 2.4 since the bug that it was Natalie> fixing has gone away. However, some large system vendors now Natalie> want this capability available through a means that can be Natalie> controlled by the platform in the event that there is an Natalie> issue with either processor or their chipset where global Natalie> ptc.g is not operational. They want the mechanism for future Natalie> platforms to work around such issues. It is also needed for Natalie> platform makers when they deliberately do not use the global Natalie> cache purge in their chipset implementation. (For such cases, Natalie> Intel provided a SAL table entry to specify if ptc.g is Natalie> allowed and how many). If you need a special TLB purge implementation, please use the machine vector as we do on the sn2 architecture - there is no reason to implement a boot time option for this. Who are these large system vendors who want this patch in? I presume it's not the people running gmail? :-) Cheers, Jes