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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 2A88BC4CECD for ; Mon, 27 Apr 2020 20:52:32 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5155E2070B for ; Mon, 27 Apr 2020 20:52:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5155E2070B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 499xmY0tNNzDqgV for ; Tue, 28 Apr 2020 06:52:29 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=ftp.linux.org.uk (client-ip=2002:c35c:fd02::1; helo=zeniv.linux.org.uk; envelope-from=viro@ftp.linux.org.uk; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=zeniv.linux.org.uk Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [IPv6:2002:c35c:fd02::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 499xjy5PzmzDqKJ for ; Tue, 28 Apr 2020 06:50:14 +1000 (AEST) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jTAhN-00D2oe-Sy; Mon, 27 Apr 2020 20:49:54 +0000 Date: Mon, 27 Apr 2020 21:49:53 +0100 From: Al Viro To: Christoph Hellwig Subject: Re: [PATCH 1/5] powerpc/spufs: simplify spufs core dumping Message-ID: <20200427204953.GY23230@ZenIV.linux.org.uk> References: <20200427200626.1622060-1-hch@lst.de> <20200427200626.1622060-2-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200427200626.1622060-2-hch@lst.de> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Arnd Bergmann , Linus Torvalds , linux-kernel@vger.kernel.org, Jeremy Kerr , linux-fsdevel@vger.kernel.org, Andrew Morton , linuxppc-dev@lists.ozlabs.org, "Eric W . Biederman" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Apr 27, 2020 at 10:06:21PM +0200, Christoph Hellwig wrote: > @@ -1988,7 +1984,12 @@ static ssize_t spufs_mbox_info_read(struct file *file, char __user *buf, > if (ret) > return ret; > spin_lock(&ctx->csa.register_lock); > - ret = __spufs_mbox_info_read(ctx, buf, len, pos); > + /* EOF if there's no entry in the mbox */ > + if (ctx->csa.prob.mb_stat_R & 0x0000ff) { > + ret = simple_read_from_buffer(buf, len, pos, > + &ctx->csa.prob.pu_mb_R, > + sizeof(ctx->csa.prob.pu_mb_R)); > + } > spin_unlock(&ctx->csa.register_lock); > spu_release_saved(ctx); Again, this really needs fixing. Preferably - as a separate commit preceding this series, so that it could be backported. simple_read_from_buffer() is a blocking operation. Yes, I understand that mainline has the same bug; it really does need to be fixed and having to backport this series is not a good idea, for obvious reasons.