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charset=us-ascii Content-Disposition: inline In-Reply-To: <20220815071332.627393-9-yuzhao@google.com> ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=DibP47fu; spf=none (imf05.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=peterz@infradead.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1665673490; a=rsa-sha256; cv=none; b=pWmb/toiVOnI5NPIz6j4rLrE8HADwj7OVfwZAarVpy4t9/rGI71/8NOUZeAZP1t+tWptoY UReiy9/Wi5rO+zH10iOcY1kqHbP3L2xyg2jMjeVjRfti+EOuQMEI4oXCGqdwvoEv4N6tnU qtvhJGfLJrla6Y4YuOLUphb/IqhNbGk= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1665673490; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=u/yanSpQBsDeBmQh9RGkX0Jb1t4uGPjofYGMl0NSrBE=; b=TLEYftX6yIN29hr8jzaa4DsXnwrum0mF+0T0iWFMJzVYOfJDv9HNgrNyah+AvA2Cho3Mf4 b5QBkjWZtKzqyCRWw/VGLYSuavADlHYN2xTv5P3oYlRLBF80TjfvaVQAjsI03UJI/XuKS7 ffMwVklr4ixHR8I5VEm3YIsXYGP/j8k= X-Rspamd-Server: rspam05 X-Rspam-User: Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=DibP47fu; spf=none (imf05.hostedemail.com: domain of peterz@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=peterz@infradead.org; dmarc=none X-Stat-Signature: zrzr1se1ges1bkkihscio77ndwigx5i6 X-Rspamd-Queue-Id: 6C520100036 X-HE-Tag: 1665673490-52310 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Aug 15, 2022 at 01:13:27AM -0600, Yu Zhao wrote: > + for (i = pmd_index(start), addr = start; addr != end; i++, addr = next) { > + pmd_t val = pmd_read_atomic(pmd + i); > + > + /* for pmd_read_atomic() */ > + barrier(); Please clarify the above. This is an entirely inadequate ordering comment. > + > + next = pmd_addr_end(addr, end);