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[209.132.180.67]) by mx.google.com with ESMTP id v10si2995556edc.224.2019.10.09.21.15.08; Wed, 09 Oct 2019 21:15:32 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=CwECIOKu; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726523AbfJJENA (ORCPT + 99 others); Thu, 10 Oct 2019 00:13:00 -0400 Received: from mail-yb1-f194.google.com ([209.85.219.194]:39929 "EHLO mail-yb1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725822AbfJJEM7 (ORCPT ); Thu, 10 Oct 2019 00:12:59 -0400 Received: by mail-yb1-f194.google.com with SMTP id v37so1496843ybi.6 for ; Wed, 09 Oct 2019 21:12:59 -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=qEPtjPzuGjvOl9Qgb3Ue32NDgtmQlr5z0USmUCvMf2I=; b=CwECIOKuXMrMo1bMsiN/eiNxrU9knsTsmCRbc6gpRI0B28U8ASS4oX6VX/4tgUoKNK 4eLEclcWJwhYFVgVPvXGbXy6b/k6uA8j+i6erNp+Fzef3NJs3Jn5935k6gvRrvWPUTN1 S45aWKRHs+cR3MMr0/0V8Xbvck4kqke22iUZ/j6NAoJtBNHDo6JzFzRqHqekEJ4QjBJ9 r2gyHp+vzMvJMBQyDkznCisJ6Zjjl3zMGh+zIk4OJP/O+SmtK7h9056ZkT7G80jj5kPN Dkt+vjE/6LnD8UvudwscHX18bE20TkibN77zqMIQZpaXvJCPqcqr/a5jYSP6Mj1TSY9E 9mng== 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=qEPtjPzuGjvOl9Qgb3Ue32NDgtmQlr5z0USmUCvMf2I=; b=RskxygEpsiF/3ucqst5jhuPKTNvEIHEUKOWTqioKREmoMtFVmp93M2Ozs7e0VnKY5G OGx33/P+7j0uHKbhxLdcHCQrgOEiWAvydhcyImbEi+KrXkAoEebV7i0tR/vZbuvfNWLo oc9oJsk+Mnf0r16OW4NXuXgmLmgmISthEDMa7QF7Ao+n+6nJRy+aaomggrjEq+5tiCvQ ZEHra4BPQIkshsE0XocIULFvyBMuhaiqqrCR+2defWQ5Op+g7SLzyrVbGZi2bVMsetW1 ZMOBEvJy5k9QwqyDkc6yFcYFdVIcO/d3Neh7nApjvoopXL23QRPY7ACBV8jQ+YEuFof0 gu8w== X-Gm-Message-State: APjAAAXHP6AdRMQwTjLXWhCP3hmS/kw9tkFN0rTGoJ1x0lmU2hqfR/fT WD+CY+N37YJ0b6Og9LTQPXxk8eeMkC0XbVeAX13TQg== X-Received: by 2002:a25:26c9:: with SMTP id m192mr4979554ybm.274.1570680778434; Wed, 09 Oct 2019 21:12:58 -0700 (PDT) MIME-Version: 1.0 References: <20191009212154.24709-1-edumazet@google.com> <20191010031820.GD2689@paulmck-ThinkPad-P72> In-Reply-To: <20191010031820.GD2689@paulmck-ThinkPad-P72> From: Eric Dumazet Date: Wed, 9 Oct 2019 21:12:46 -0700 Message-ID: Subject: Re: [PATCH] rcu: avoid data-race in rcu_gp_fqs_check_wake() To: paulmck@kernel.org Cc: linux-kernel , Eric Dumazet , syzbot Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 9, 2019 at 8:18 PM Paul E. McKenney wrote: > Again, good catch, applied for review and testing, thank you! > > I added another READ_ONCE() to dump_blkd_tasks(), which is not exercised > unless you get an RCU CPU stall warning or some such. The updated patch > is below, please let me know if I messed anything up. > > Thanx, Paul This looks good to me, thanks Paul.