Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752250AbbLDN11 (ORCPT ); Fri, 4 Dec 2015 08:27:27 -0500 Received: from mx1.redhat.com ([209.132.183.28]:34775 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751348AbbLDN10 (ORCPT ); Fri, 4 Dec 2015 08:27:26 -0500 Date: Fri, 4 Dec 2015 07:27:24 -0600 From: Josh Poimboeuf To: Jiri Kosina Cc: Rusty Russell , Seth Jennings , Vojtech Pavlik , linux-kernel@vger.kernel.org, live-patching@vger.kernel.org, Miroslav Benes Subject: Re: [PATCH v4] livepatch: Cleanup module page permission changes Message-ID: <20151204132724.GH11394@treble.redhat.com> References: <9b321c4c2edeaff43f21040a883891a691fc1978.1449181535.git.jpoimboe@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2553 Lines: 59 On Fri, Dec 04, 2015 at 01:11:29AM +0100, Jiri Kosina wrote: > On Thu, 3 Dec 2015, Josh Poimboeuf wrote: > > > Calling set_memory_rw() and set_memory_ro() for every iteration of the > > loop in klp_write_object_relocations() is messy, inefficient, and > > error-prone. > > > > Change all the read-only pages to read-write before the loop and convert > > them back to read-only again afterwards. > > > > Suggested-by: Miroslav Benes > > Signed-off-by: Josh Poimboeuf > > --- > > Based on the following branches: > > - git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching.git for-4.5/core > > - git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux.git modules-next > > > > - v4: rebase onto Chris's sympos changes > > - v3: use new module_{disable,enable}_ro() functions (in linux-next) > > Rusty, > > how would you like to handle this cross-tree dependency? > > My proposals: > > (1) I pull your 'modules-next' branch, apply this patch on top, and wait > for your merge with Linus and send merge request afterwards > (2) If you are okay with rebasing your tree (seems like this is > ocassionally happening), how about you prepare a branch that'd have > just b3212ec77 ("module: keep percpu symbols in module's symtab") on > top of some common base, I merge it, and the cross-dependency is gone > (3) I cherry-pick b3212ec77 ("module: keep percpu symbols in > module's symtab") from your tree, and apply this on top. git will > handle duplicate commits when Linus merges both just fine > (4) I sign this patch off and you merge it > > (4) seems really outside the regular process. (1) is really tricky wrt. > coordination of timing during the merge window. I'd prefer (2) (more > git-ish way of doing things, but would require you rebasing your tree) or > eventually (3) (git will handle this with grace). [ off-list ] Quick question. Just curious, because I'm new at this... My impression was that #1 was standard operating procedure. Merge a (non-rebasable) modules branch into livepatch, and then make sure to submit the livepatch pull request after Rusty sends his, with a note in the mail to Linus stating the dependency. That seems pretty straightforward to me. Or am I missing something? -- Josh -- 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/