Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755279AbbFLWpx (ORCPT ); Fri, 12 Jun 2015 18:45:53 -0400 Received: from mail-qk0-f177.google.com ([209.85.220.177]:34707 "EHLO mail-qk0-f177.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755171AbbFLWpu (ORCPT ); Fri, 12 Jun 2015 18:45:50 -0400 MIME-Version: 1.0 In-Reply-To: References: <1434066338-6619-1-git-send-email-srinivas.pandruvada@linux.intel.com> <20150612060747.GA25024@gmail.com> <20150612075013.GA8759@gmail.com> <20150612083625.GA22760@gmail.com> From: Denys Vlasenko Date: Sat, 13 Jun 2015 00:45:29 +0200 Message-ID: Subject: Re: [PATCH] x86: General protection fault after STR (32 bit systems only) To: Brian Gerst Cc: Ingo Molnar , "H. Peter Anvin" , Andy Lutomirski , Srinivas Pandruvada , Ingo Molnar , Thomas Gleixner , Pavel Machek , "Rafael J. Wysocki" , X86 ML , "linux-pm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Denys Vlasenko , Borislav Petkov , Linus Torvalds Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 910 Lines: 33 On Fri, Jun 12, 2015 at 5:48 PM, Brian Gerst wrote: > If you follow the convoluted flow of the calls in this file, > ... Speaking of which. It is indeed quite bad. For one, saved_eip is only ever set to point to ret_point: ENTRY(saved_eip) .long 0 ... movl $ret_point, saved_eip and it has just a single user, where an indirect jump through it is performed: # jump to place where we left off movl saved_eip, %eax jmp *%eax No comments why it is so. All this seems to be equivalent to trivial # jump to place where we left off jmp ret_point Am I missing something? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/