From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756425AbbDJWxA (ORCPT ); Fri, 10 Apr 2015 18:53:00 -0400 Received: from one.firstfloor.org ([193.170.194.197]:45718 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756194AbbDJWw7 (ORCPT ); Fri, 10 Apr 2015 18:52:59 -0400 Date: Sat, 11 Apr 2015 00:52:56 +0200 From: Andi Kleen To: Andy Lutomirski Cc: Andi Kleen , Andi Kleen , X86 ML , Andrew Lutomirski , "linux-kernel@vger.kernel.org" , Steven Rostedt , Borislav Petkov Subject: Re: [PATCH 4/8] x86: Add support for rd/wr fs/gs base Message-ID: <20150410225256.GY2366@two.firstfloor.org> References: <1428681033-1549-1-git-send-email-andi@firstfloor.org> <1428681033-1549-5-git-send-email-andi@firstfloor.org> <20150410202132.GQ15335@tassilo.jf.intel.com> <20150410204125.GS15335@tassilo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > I think all of this stems from unfortunate naming. DEBUG_STACK isn't > one stack -- it's a debug stack *array*. The IST shift mechanism > means that we can use different entries in that array as our stacks > depending on how deeply nested we are. It's not. It was always intended as one stack. It still is, for anyone not nesting debuggers (which afaik doesn't happen in-tree, it was only for Jan Beulich's magic debugger) I wrote the original code, so I should know. -Andi -- ak@linux.intel.com -- Speaking for myself only.