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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 0C850C433ED for ; Mon, 17 May 2021 14:41:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA69E61CFF for ; Mon, 17 May 2021 14:41:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240387AbhEQOml (ORCPT ); Mon, 17 May 2021 10:42:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:60372 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240943AbhEQOgt (ORCPT ); Mon, 17 May 2021 10:36:49 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id E792F613F5; Mon, 17 May 2021 14:17:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621261051; bh=mvSNo2h6pfdLUgGDYX/30/W/KCYOBhTjAIbMZFnCgUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hCdj5yyRj+9OGzzx0hx0RRjIcbGiV6rea9+sJpCyF+XhMTLHfrtCuBPpgNIa3EdPO u7m+s4Pj+NhX5l6zO872GW2fp5ZNH6W0Sm7kdisr04AIYl/HUh8MeSzrxIkgGpw5tJ HyZwG95/XQ89QuLo6tSAtC+JGFn4uaZUqind9VzE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Chaitanya Kulkarni , Sagi Grimberg , Christoph Hellwig , Sasha Levin Subject: [PATCH 5.12 298/363] nvmet: fix inline bio check for passthru Date: Mon, 17 May 2021 16:02:44 +0200 Message-Id: <20210517140312.677846662@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210517140302.508966430@linuxfoundation.org> References: <20210517140302.508966430@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chaitanya Kulkarni [ Upstream commit ab96de5def854d8fc51280b6a20597e64b14ac31 ] When handling passthru commands, for inline bio allocation we only consider the transfer size. This works well when req->sg_cnt fits into the req->inline_bvec, but it will result in the early return from bio_add_hw_page() when req->sg_cnt > NVMET_MAX_INLINE_BVEC. Consider an I/O of size 32768 and first buffer is not aligned to the page boundary, then I/O is split in following manner :- [ 2206.256140] nvmet: sg->length 3440 sg->offset 656 [ 2206.256144] nvmet: sg->length 4096 sg->offset 0 [ 2206.256148] nvmet: sg->length 4096 sg->offset 0 [ 2206.256152] nvmet: sg->length 4096 sg->offset 0 [ 2206.256155] nvmet: sg->length 4096 sg->offset 0 [ 2206.256159] nvmet: sg->length 4096 sg->offset 0 [ 2206.256163] nvmet: sg->length 4096 sg->offset 0 [ 2206.256166] nvmet: sg->length 4096 sg->offset 0 [ 2206.256170] nvmet: sg->length 656 sg->offset 0 Now the req->transfer_size == NVMET_MAX_INLINE_DATA_LEN i.e. 32768, but the req->sg_cnt is (9) > NVMET_MAX_INLINE_BIOVEC which is (8). This will result in early return in the following code path :- nvmet_bdev_execute_rw() bio_add_pc_page() bio_add_hw_page() if (bio_full(bio, len)) return 0; Use previously introduced helper nvmet_use_inline_bvec() to consider req->sg_cnt when using inline bio. This only affects nvme-loop transport. Fixes: dab3902b19a0 ("nvmet: use inline bio for passthru fast path") Signed-off-by: Chaitanya Kulkarni Reviewed-by: Sagi Grimberg Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin --- drivers/nvme/target/passthru.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvme/target/passthru.c b/drivers/nvme/target/passthru.c index 2798944899b7..39b1473f7204 100644 --- a/drivers/nvme/target/passthru.c +++ b/drivers/nvme/target/passthru.c @@ -194,7 +194,7 @@ static int nvmet_passthru_map_sg(struct nvmet_req *req, struct request *rq) if (req->sg_cnt > BIO_MAX_VECS) return -EINVAL; - if (req->transfer_len <= NVMET_MAX_INLINE_DATA_LEN) { + if (nvmet_use_inline_bvec(req)) { bio = &req->p.inline_bio; bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec)); } else { -- 2.30.2