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=-2.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 1963DC3A5A6 for ; Fri, 30 Aug 2019 06:23:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D542221721 for ; Fri, 30 Aug 2019 06:23:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567146233; bh=PRUhatSeU/3T/AMs4GtzyoWnaRohArYodojMqtzoabU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=c+5zX1+h0Ge9nNiMFj5KtxbA5vkfpv4ok3w9ZeV4Qalujagye/2L79vGAsn+dcGcB dwNGnNJwsWH45pb9niA9O6U+qcvly3Rb2QmJIXjTQdmFcxRAIWbqo4Y2037y1nNhF2 ibk+LWES1nfSX/DLoeR6rmpOmyrT8kBQnReCl4Ag= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727901AbfH3GXx (ORCPT ); Fri, 30 Aug 2019 02:23:53 -0400 Received: from mail.kernel.org ([198.145.29.99]:57170 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726716AbfH3GXw (ORCPT ); Fri, 30 Aug 2019 02:23:52 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 650872186A; Fri, 30 Aug 2019 06:23:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567146231; bh=PRUhatSeU/3T/AMs4GtzyoWnaRohArYodojMqtzoabU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=swdgx3EeSI3MsNB2JN+gyh2gKdV4OMK7dXbAeJgOizr6RUJr++DN4edDVGSPIbQxt thdqo0EL1GE5KzHAAuHu40kZs6M/USeadSEQHm4yQV1xz8Nq6639uJSH9VzKlKnA0z +R6kl9HxgSSj7hszfCA3EUQyb1tRogq6pGuEYJdw= Date: Fri, 30 Aug 2019 08:23:49 +0200 From: Greg Kroah-Hartman To: Tyler Hicks Cc: Sasha Levin , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Todd Kjos , 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: <20190830062349.GB15257@kroah.com> 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 Content-Disposition: inline In-Reply-To: <20190829151052.GB27650@elm> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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. But the patch says: Fixes: 5cec2d2e5839 ("binder: fix race between munmap() and direct reclaim") and that commit is in 4.14.124. thanks, greg k-h