From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Tue, 13 Jul 2004 05:23:11 +0000 Subject: Re: serious performance regression due to NX patch Message-Id: <16627.29119.12240.152760@napali.hpl.hp.com> List-Id: References: <200407100528.i6A5SF8h020094@napali.hpl.hp.com> <20040711123803.GD21264@devserv.devel.redhat.com> <16626.62318.880165.774044@napali.hpl.hp.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Ingo Molnar Cc: davidm@hpl.hp.com, Linus Torvalds , Jakub Jelinek , suresh.b.siddha@intel.com, jun.nakajima@intel.com, Andrew Morton , linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org >>>>> On Tue, 13 Jul 2004 00:23:29 -0400 (EDT), Ingo Molnar said: Ingo> it's not just about the stack! It's a "is the value of the Ingo> PROT_EXEC bit just an embelishment of /proc output or is it Ingo> taken seriously" thing. Fine, but it seems to me NX bit patch wasn't properly integrated with VM_DATA_DEFAULT_FLAGS. In fact, if you hadn't changed the x86 version of VM_DATA_DEFAULT_FLAGS and instead had in mm/mmap.c replaced the macro with (VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE), then things would have behaved exactly right with my patch applied and the logic would make much more sense. There would also need to be a small change to arch/ia64/mm/init.c, but I'd be happy to take care of that. --david