Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932408Ab1BKV0H (ORCPT ); Fri, 11 Feb 2011 16:26:07 -0500 Received: from cantor2.suse.de ([195.135.220.15]:41560 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932175Ab1BKV0F (ORCPT ); Fri, 11 Feb 2011 16:26:05 -0500 Date: Fri, 11 Feb 2011 13:23:52 -0800 From: Greg KH To: KY Srinivasan Cc: "linux-kernel@vger.kernel.org" , "devel@linuxdriverproject.org" , "virtualization@lists.osdl.org" , Hank Janssen Subject: Re: [PATCH 1/3]: Staging: hv: Use native page allocation/free functions Message-ID: <20110211212352.GA10845@suse.de> References: <1297447140-21777-1-git-send-email-kys@microsoft.com> <20110211182949.GA10751@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2123 Lines: 54 On Fri, Feb 11, 2011 at 08:55:56PM +0000, KY Srinivasan wrote: > > > > -----Original Message----- > > From: Greg KH [mailto:gregkh@suse.de] > > Sent: Friday, February 11, 2011 1:30 PM > > To: KY Srinivasan > > Cc: linux-kernel@vger.kernel.org; devel@linuxdriverproject.org; > > virtualization@lists.osdl.org; Hank Janssen > > Subject: Re: [PATCH 1/3]: Staging: hv: Use native page allocation/free functions > > > > On Fri, Feb 11, 2011 at 09:59:00AM -0800, K. Y. Srinivasan wrote: > > > --- a/drivers/staging/hv/hv.c > > > +++ b/drivers/staging/hv/hv.c > > > @@ -230,7 +230,12 @@ int hv_init(void) > > > * Allocate the hypercall page memory > > > * virtaddr = osd_page_alloc(1); > > > */ > > > - virtaddr = osd_virtual_alloc_exec(PAGE_SIZE); > > > +#ifdef __x86_64__ > > > + virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, PAGE_KERNEL_EXEC); > > #else > > > + virtaddr = __vmalloc(PAGE_SIZE, GFP_KERNEL, > > > + __pgprot(__PAGE_KERNEL & (~_PAGE_NX))); #endif > > > > I'm not saying this patch is wrong at all, but I still don't understand why this is > > different depending on the architecture of the machine. Why is this necessary, it > > should be ok to do the same type of allocation no matter what the processor is, > > right? > > You are right Greg; I don't think there is a need to specify different page > protection bits based on the architecture - PAGE_KERNEL_EXEC should be enough. I thought so, but for some reason Hank said there this was needed. Hank, is it still true? > However, this is the code that is currently in the tree - refer to osd.c. Oh, I remember, it's not a critique of this patch, it just reminded me of this question I always had for this code. > If it is ok with you, I could submit an additional patch to clean this up. If Hank says it is ok, and you all test it to verify nothing breaks, please send it on. thanks, greg k-h -- 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/