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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 16E83C4332B for ; Mon, 4 Jan 2021 13:08:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DE55221D93 for ; Mon, 4 Jan 2021 13:08:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726875AbhADNIH (ORCPT ); Mon, 4 Jan 2021 08:08:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46996 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726829AbhADNIH (ORCPT ); Mon, 4 Jan 2021 08:08:07 -0500 Received: from mail-pj1-x1029.google.com (mail-pj1-x1029.google.com [IPv6:2607:f8b0:4864:20::1029]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E1CB2C061794; Mon, 4 Jan 2021 05:07:26 -0800 (PST) Received: by mail-pj1-x1029.google.com with SMTP id b5so10845600pjk.2; Mon, 04 Jan 2021 05:07:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=b1nywf6L60SmI9ZxVA0bUc4AidIu1KLiq6fBICYuXas=; b=eoqPwHxa2w/HIdzENiSVcV9Fj0kFoNN99+KWTCjmPuACB1GmmKWDz4sq9kdd6tWlH5 PQUDWrFzOr892t//WfI44QVM/oM1PUYDkKAxSnpdRI9zr4eRhLtVKrebf2lOOeMJejEB nZ10TX9rG9J0koa+xyrtihpFJhXkmhEpu5whkNw/ScnWLUFMj94RVva7TPYxCynHJwnd Xz3cbudYvDB32ftkI14O/In+Wn9roqrMwiVnIbA8Hr3bYj24yOoGnORWNrHhRgqkUeJa cDlQf1J8sEQzcj9+y18qnIZLNXlNcS/TL4D+MJthpqyu1Z0Io7DeZulAIPLpWaNgB+2o 2BEw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=b1nywf6L60SmI9ZxVA0bUc4AidIu1KLiq6fBICYuXas=; b=MKrU6OwujtCgt7Obn96PN0zot2n9CL8KLqCgOm2W2fblJB5YNPlX2NH5IZou8X4aIz SlHoARNFCu8bNs+C694/uQniP6xi4L0oo+j5SYSImBdORnvR2x2UCNZrKCXAOYSwMY+4 N1zwDc8TvFT/FM5pAAznC9upoDBALaNM3FCA5LQYwzBA1QirMZU7NmTtPDf0/OFgJoh8 k3vd+JqCqXFXlanxtmBiDKIH8mYdlGtcIZyJYqOHHjZYPdAODNia7mwz3Nndk/mThTB/ aeEniLzXB65hLnPGpV2okmCl4RI+TywEGmAF1kj3ZukoIfiQsMxgKj5Ylsiemj6zMtwM pFDw== X-Gm-Message-State: AOAM531eefQd5tym/vSL3GO+UlU31Yq2EkMDpmIY7213Er5q+uvkgmhV mMdEw8lriJrL8ceB7tNlQOGY0Wy8wgk= X-Google-Smtp-Source: ABdhPJwnW1RvrcVODnW70uNtPrYbnrpCk9WOqcxhEq9h1Nv1rIwy4bvzp7Yhn53VtkNUphXFsu0vOg== X-Received: by 2002:a17:902:7b83:b029:db:d71b:2c4d with SMTP id w3-20020a1709027b83b02900dbd71b2c4dmr72142144pll.81.1609765646299; Mon, 04 Jan 2021 05:07:26 -0800 (PST) Received: from localhost.localdomain ([211.108.35.36]) by smtp.gmail.com with ESMTPSA id b189sm55303786pfb.194.2021.01.04.05.07.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 04 Jan 2021 05:07:25 -0800 (PST) From: Minwoo Im To: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Jens Axboe , Alexander Viro , Christoph Hellwig , Chaitanya Kulkarni , Minwoo Im Subject: [RFC PATCH V3 1/1] block: reject I/O for same fd if block size changed Date: Mon, 4 Jan 2021 22:06:59 +0900 Message-Id: <20210104130659.22511-2-minwoo.im.dev@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210104130659.22511-1-minwoo.im.dev@gmail.com> References: <20210104130659.22511-1-minwoo.im.dev@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org This patch fixes I/O errors during BLKRRPART ioctl() behavior right after format operation that changed logical block size of the block device with a same file descriptor opened. This issue can be easily reproduced with a single format command in case of NVMe (logical block size 512B to 4096B). nvme format /dev/nvme0n1 --lbaf=1 --force This is because the application, nvme-cli format subcommand issues an admin command followed by BLKRRPART ioctl to re-read partition information without closing the file descriptor. If file descriptor stays opened, __blkdev_get() will not be invoked at all even logical block size has been changed. It will cause I/O errors with invalid Read operations during the BLKRRPART ioctl due to i_blkbits mismatch. The invalid operations in BLKRRPART happens with under-flowed Number of LBA(NLB) values 0xffff(65535) because i_blkbits is still set to 9 even the logical block size has been updated to 4096. The BLKRRPART will lead buffer_head to hold 512B data which is less than the logical lock size of the block device. The root cause, which is because i_blkbits of inode of the block device is not updated, can be solved easily by re-opening file descriptor again from application. But, that's just for application's business and kernel should reject invalid Read operations during the BLKRRPART ioctl. This patch rejects I/O from the path of add_partitions() to avoid issuing invalid Read operations to device. It also sets a flag to gendisk in blk_queue_logical_block_size to minimize caller-side updates. Signed-off-by: Minwoo Im --- block/blk-settings.c | 8 ++++++++ block/partitions/core.c | 11 +++++++++++ fs/block_dev.c | 6 ++++++ include/linux/genhd.h | 1 + 4 files changed, 26 insertions(+) diff --git a/block/blk-settings.c b/block/blk-settings.c index 43990b1d148b..84136ea4e2a4 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -328,6 +328,14 @@ EXPORT_SYMBOL(blk_queue_max_segment_size); void blk_queue_logical_block_size(struct request_queue *q, unsigned int size) { struct queue_limits *limits = &q->limits; + struct block_device *bdev; + + if (q->backing_dev_info && q->backing_dev_info->owner && + limits->logical_block_size != size) { + bdev = blkdev_get_no_open(q->backing_dev_info->owner->devt); + bdev->bd_disk->flags |= GENHD_FL_BLOCK_SIZE_CHANGED; + blkdev_put_no_open(bdev); + } limits->logical_block_size = size; diff --git a/block/partitions/core.c b/block/partitions/core.c index e7d776db803b..5a0330c1b6f9 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -618,6 +618,17 @@ int blk_add_partitions(struct gendisk *disk, struct block_device *bdev) if (!disk_part_scan_enabled(disk)) return 0; + /* + * Reject to check partition information if block size has been changed + * in the runtime. If block size of a block device has been changed, + * the file descriptor should be opened agian to update the blkbits. + */ + if (disk->flags & GENHD_FL_BLOCK_SIZE_CHANGED) { + pr_warn("%s: rejecting checking partition. fd should be opened again.\n", + disk->disk_name); + return -EBADFD; + } + state = check_partition(disk, bdev); if (!state) return 0; diff --git a/fs/block_dev.c b/fs/block_dev.c index 9293045e128c..c996de3d6084 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -131,6 +131,12 @@ EXPORT_SYMBOL(truncate_bdev_range); static void set_init_blocksize(struct block_device *bdev) { bdev->bd_inode->i_blkbits = blksize_bits(bdev_logical_block_size(bdev)); + + /* + * Allow I/O commands for this block device. We can say that this + * block device has been set to a proper block size. + */ + bdev->bd_disk->flags &= ~GENHD_FL_BLOCK_SIZE_CHANGED; } int set_blocksize(struct block_device *bdev, int size) diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 809aaa32d53c..0e0e24917003 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -103,6 +103,7 @@ struct partition_meta_info { #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 0x0100 #define GENHD_FL_NO_PART_SCAN 0x0200 #define GENHD_FL_HIDDEN 0x0400 +#define GENHD_FL_BLOCK_SIZE_CHANGED 0x0800 enum { DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */ -- 2.17.1