From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C0BAC3A59F for ; Thu, 29 Aug 2019 16:42:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C21C12189D for ; Thu, 29 Aug 2019 16:42:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567096939; bh=bRpqTp3EjTmLNhGd3WmD0wtWWTzJRaoQEOOaMMh/9qU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=P6TrXsu3txVKMDwUtPTWz+VxY8MqY8vxD1C4oDbPTwFX960XuEFNTFj1M0AdI1jmh 3Tcfqn5n1yBtjhLWtjWVrNRSlGOZN7wgT3NnPat+766bpZCRqJnaiHSXtfKli3cWCf e3iq/RczjJemNJsLdahqOfAPxN/gDmX2uRVhMvPw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727417AbfH2QmT (ORCPT ); Thu, 29 Aug 2019 12:42:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:48674 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727115AbfH2QmT (ORCPT ); Thu, 29 Aug 2019 12:42:19 -0400 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 031752070B; Thu, 29 Aug 2019 16:42:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567096938; bh=bRpqTp3EjTmLNhGd3WmD0wtWWTzJRaoQEOOaMMh/9qU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KtLG/S2tSMFYc5IJeMsFlWVsyXjpRehwx+Mw4Cy0TBEsERF1DhBJvMZRxuTwnvkp1 uVRPCVZrPmtgecc0hldS6Ie+52Q28fIDUhduZu7Z/L0nV18MC9bRH2qqx/a27YBkx6 YQdw+rvueX/1l73Y6Gri7rMc/Vc/YyKvYOP05VCA= Date: Thu, 29 Aug 2019 12:42:17 -0400 From: Sasha Levin To: Tyler Hicks Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Todd Kjos , Greg Kroah-Hartman , devel@driverdev.osuosl.org Subject: Re: [PATCH AUTOSEL 4.14 05/14] binder: take read mode of mmap_sem in binder_alloc_free_page() Message-ID: <20190829164217.GJ5281@sasha-vm> References: <20190829105043.2508-1-sashal@kernel.org> <20190829105043.2508-5-sashal@kernel.org> <20190829151052.GB27650@elm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20190829151052.GB27650@elm> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Thu, Aug 29, 2019 at 10:10:52AM -0500, Tyler Hicks wrote: >Hello, Sasha! > >On 2019-08-29 06:50:34, Sasha Levin wrote: >> From: Tyler Hicks >> >> [ Upstream commit 60d4885710836595192c42d3e04b27551d30ec91 ] >> >> Restore the behavior of locking mmap_sem for reading in >> binder_alloc_free_page(), as was first done in commit 3013bf62b67a >> ("binder: reduce mmap_sem write-side lock"). That change was >> inadvertently reverted by commit 5cec2d2e5839 ("binder: fix race between >> munmap() and direct reclaim"). >> >> In addition, change the name of the label for the error path to >> accurately reflect that we're taking the lock for reading. >> >> Backporting note: This fix is only needed when *both* of the commits >> mentioned above are applied. That's an unlikely situation since they >> both landed during the development of v5.1 but only one of them is >> targeted for stable. > >This patch isn't meant to be applied to 4.14 since commit 3013bf62b67a >("binder: reduce mmap_sem write-side lock") was never brought back to >4.14. > >My backporting note above isn't helpful for AUTOSEL purposes. Do you >have a suggestion for what I could have done in the patch tags to convey >that guidance to AUTOSEL? Hey Tyler, No, this is just me messing up. AUTOSEL actually handled this well. What happened here you ask? This series is basically a set of patches that fix a different fix that went into stable. It didn't go through the regular AUTOSEL flow and I goofed up manually. Sorry for the noise, I've dropped the patch. -- Thanks, Sasha