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=-13.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_IN_DEF_DKIM_WL 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 33FFCC47080 for ; Tue, 1 Jun 2021 18:05:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id BD1A461375 for ; Tue, 1 Jun 2021 18:05:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BD1A461375 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 4CEA76B006C; Tue, 1 Jun 2021 14:05:47 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 47E406B006E; Tue, 1 Jun 2021 14:05:47 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 346936B0070; Tue, 1 Jun 2021 14:05:47 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0002.hostedemail.com [216.40.44.2]) by kanga.kvack.org (Postfix) with ESMTP id 0485F6B006C for ; Tue, 1 Jun 2021 14:05:46 -0400 (EDT) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 9D397B7BB for ; Tue, 1 Jun 2021 18:05:46 +0000 (UTC) X-FDA: 78205933092.10.C39C281 Received: from mail-pj1-f49.google.com (mail-pj1-f49.google.com [209.85.216.49]) by imf06.hostedemail.com (Postfix) with ESMTP id 1A1CEC00CBE7 for ; Tue, 1 Jun 2021 18:05:34 +0000 (UTC) Received: by mail-pj1-f49.google.com with SMTP id g6-20020a17090adac6b029015d1a9a6f1aso184857pjx.1 for ; Tue, 01 Jun 2021 11:05:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=tFi+0ZXy3DnUaNTWR7lHK+Jvu+Euee8I+krnOUNTIo8=; b=uOhIrF0skcVRYvW/sWyGzJPs4UT01Htakzfx7vc3yQzsMjnKVxV0Wfce9cVPXmlC/s z99yd7kpG6/139ktjuDyzt1OHgvrhKn3qsLaVNrdVeBJTH9HNcb6fsV1GuOGc0wtLz1M EB79TwLnP4jUMIpAvnHG68rQk0JYYaKPri9zyS9W880HpvcGMYjppN9ooy3hffkEic0B odDc9ifCiGlr7scq7BxPOMACHhf0LcEYs3MLh/NL9XBpluljMRzvQaPkF0vD9dxJ9YNq 80Fs3QV0QhKvkJA/2AzWHtDrweSk6RtCqwgHplNbaBJjDdD7b2JIdOgVKE5i/xVybiyx l2LQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=tFi+0ZXy3DnUaNTWR7lHK+Jvu+Euee8I+krnOUNTIo8=; b=B3YbXLbLf0989IbBVKcxRLd7uso3kHhCs8RMKJN3TaXZ69Si2Fgj5tvMAjwVK288So NqUuqtDPW4SZVqtrXG55ZRG/AMvyellHdbtrY4y8+dLvAwEIEYOb1NLnptEi4YyICQrJ srvNxz1cW6WYRELJ0AhGpbjHl3XRPhFehLQWxr/ukVYi1zuuv8aJflJcK0qs4TXjDvGg LY1YDRc5Koucy4/5nq6yyPi7wbmSTnPrknzspN+lRWfnaGVWqukHD6kPt9eUiQBdWNo5 IecWZeI/9U0vntZLdI1wrAffYhmMAsYbQB+vs89TiL33j/oABklTOPA47XofGSNGvXUN r1Zw== X-Gm-Message-State: AOAM5335q5fu767tfAD0r1IN2gbamtuvUujvldTC7hpwpSUH/Q+dk6n8 rIixW6Lm12GCWN2c3I6qXnxm6i5av2C2XcL2oub2vw== X-Google-Smtp-Source: ABdhPJwSvmFlvlvBNl2uR19/9PrU1TWWKo+7aepgOx3AgZNM8LBx5JAocjwfD9LASD/WwCHDZM24bSiyHNHt8DTyzRU= X-Received: by 2002:a17:902:e5ca:b029:109:8857:af7e with SMTP id u10-20020a170902e5cab02901098857af7emr1793368plf.82.1622570745134; Tue, 01 Jun 2021 11:05:45 -0700 (PDT) MIME-Version: 1.0 References: <20210528005029.88088-1-almasrymina@google.com> <20210531162527.caeae9545ea2843c5f62bc9c@linux-foundation.org> <20210531173652.c21404a16a8f8542ce40afa8@linux-foundation.org> <83617ae4-90a1-24d0-a79c-4e259a928e04@oracle.com> In-Reply-To: From: Mina Almasry Date: Tue, 1 Jun 2021 11:05:34 -0700 Message-ID: Subject: Re: [PATCH v4] mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY To: Mike Kravetz Cc: Andrew Morton , Axel Rasmussen , Peter Xu , Linux-MM , open list Content-Type: text/plain; charset="UTF-8" X-Rspamd-Queue-Id: 1A1CEC00CBE7 Authentication-Results: imf06.hostedemail.com; dkim=pass header.d=google.com header.s=20161025 header.b=uOhIrF0s; spf=pass (imf06.hostedemail.com: domain of almasrymina@google.com designates 209.85.216.49 as permitted sender) smtp.mailfrom=almasrymina@google.com; dmarc=pass (policy=reject) header.from=google.com X-Rspamd-Server: rspam04 X-Stat-Signature: oh5cyi6khr8m1rmy96iamsk191kugyhc X-HE-Tag: 1622570734-787569 X-Bogosity: Ham, tests=bogofilter, spamicity=0.127307, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > > Mina, does this patch depend on changes to restore_reserve_on_error()? > > > > Yes, this patch (and only this patch) depends on your changes for > complete and correct functionality. I'm not sure what's the impact ...of missing your changes aside from the underflow. The userfaultfd tests still pass.