From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 51DB7373BEB; Wed, 20 May 2026 17:08:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779296897; cv=none; b=UU9F1Rz93I7LXnI1aN8W7R2klY24cVmukFSnOgAtuajyH2L5XOVmpqQvWJ/PqvYO5NkRmzjT6BKAAJ3VeWwBUmg4MrSzLL7lVGVeikk7QJL9+UldYwtyT+xJN2oCpQWc51jGTA4WRO3ghnZMJASgPGduAeSvSi42oH/jHviDjLE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779296897; c=relaxed/simple; bh=NKfsz8nsIva7DoWie1H1XQXSZweQxtquPbLYRWjV1QM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CLd9zsa85ZsXTzZlNZBtVa2sEr2TR5irxBO6wZ30sWjOLboH3PTk387ATg7ruDhOKUc/0e/Gz8QQ285eYhqikayuL4blLCtlkRuD+2arfFK5ToQuHyzIUQZZvS5r3YxT2DjBC9ClIJg6TUlaHRJ9RPpCduOOV1AcFpqgKtwrKks= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=k29Ya9Hk; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="k29Ya9Hk" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B83461F000E9; Wed, 20 May 2026 17:08:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779296896; bh=K7gkumkKoqESQNWF5T41jAi9jayz/+iIg2JziZPk7As=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=k29Ya9HkEo6X/t9jsQVjsy/FL4rJX+D1XkZclBKzjppZ4I2xLIcZ/qG/Ntp9gfQdK n+G5PJMTGU50jzt/Rwnqd5L1vtkWmIRqWkE/J3+u/Hb59vFNJSJYNMfBlyKXu2A7ek qIf83OYz6bi1YZBIGKPnCIW7cVKpk4rszSsWo8T8= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yu Kuai , Sasha Levin Subject: [PATCH 7.0 0956/1146] md: add fallback to correct bitmap_ops on version mismatch Date: Wed, 20 May 2026 18:20:06 +0200 Message-ID: <20260520162209.869161306@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162148.390695140@linuxfoundation.org> References: <20260520162148.390695140@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yu Kuai [ Upstream commit 09af773650024279a60348e7319d599e6571b15c ] If default bitmap version and on-disk version doesn't match, and mdadm is not the latest version to set bitmap_type, set bitmap_ops based on the disk version. Link: https://lore.kernel.org/linux-raid/20260323054644.3351791-2-yukuai@fnnas.com/ Signed-off-by: Yu Kuai Stable-dep-of: f2926a533d03 ("md/md-bitmap: add a none backend for bitmap grow") Signed-off-by: Sasha Levin --- drivers/md/md.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 110 insertions(+), 1 deletion(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 9c552904a5ddc..99a5ba1485565 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -6465,15 +6465,124 @@ static void md_safemode_timeout(struct timer_list *t) static int start_dirty_degraded; +/* + * Read bitmap superblock and return the bitmap_id based on disk version. + * This is used as fallback when default bitmap version and on-disk version + * doesn't match, and mdadm is not the latest version to set bitmap_type. + */ +static enum md_submodule_id md_bitmap_get_id_from_sb(struct mddev *mddev) +{ + struct md_rdev *rdev; + struct page *sb_page; + bitmap_super_t *sb; + enum md_submodule_id id = ID_BITMAP_NONE; + sector_t sector; + u32 version; + + if (!mddev->bitmap_info.offset) + return ID_BITMAP_NONE; + + sb_page = alloc_page(GFP_KERNEL); + if (!sb_page) { + pr_warn("md: %s: failed to allocate memory for bitmap\n", + mdname(mddev)); + return ID_BITMAP_NONE; + } + + sector = mddev->bitmap_info.offset; + + rdev_for_each(rdev, mddev) { + u32 iosize; + + if (!test_bit(In_sync, &rdev->flags) || + test_bit(Faulty, &rdev->flags) || + test_bit(Bitmap_sync, &rdev->flags)) + continue; + + iosize = roundup(sizeof(bitmap_super_t), + bdev_logical_block_size(rdev->bdev)); + if (sync_page_io(rdev, sector, iosize, sb_page, REQ_OP_READ, + true)) + goto read_ok; + } + pr_warn("md: %s: failed to read bitmap from any device\n", + mdname(mddev)); + goto out; + +read_ok: + sb = kmap_local_page(sb_page); + if (sb->magic != cpu_to_le32(BITMAP_MAGIC)) { + pr_warn("md: %s: invalid bitmap magic 0x%x\n", + mdname(mddev), le32_to_cpu(sb->magic)); + goto out_unmap; + } + + version = le32_to_cpu(sb->version); + switch (version) { + case BITMAP_MAJOR_LO: + case BITMAP_MAJOR_HI: + case BITMAP_MAJOR_CLUSTERED: + id = ID_BITMAP; + break; + case BITMAP_MAJOR_LOCKLESS: + id = ID_LLBITMAP; + break; + default: + pr_warn("md: %s: unknown bitmap version %u\n", + mdname(mddev), version); + break; + } + +out_unmap: + kunmap_local(sb); +out: + __free_page(sb_page); + return id; +} + static int md_bitmap_create(struct mddev *mddev) { + enum md_submodule_id orig_id = mddev->bitmap_id; + enum md_submodule_id sb_id; + int err; + if (mddev->bitmap_id == ID_BITMAP_NONE) return -EINVAL; if (!mddev_set_bitmap_ops(mddev)) return -ENOENT; - return mddev->bitmap_ops->create(mddev); + err = mddev->bitmap_ops->create(mddev); + if (!err) + return 0; + + /* + * Create failed, if default bitmap version and on-disk version + * doesn't match, and mdadm is not the latest version to set + * bitmap_type, set bitmap_ops based on the disk version. + */ + mddev_clear_bitmap_ops(mddev); + + sb_id = md_bitmap_get_id_from_sb(mddev); + if (sb_id == ID_BITMAP_NONE || sb_id == orig_id) + return err; + + pr_info("md: %s: bitmap version mismatch, switching from %d to %d\n", + mdname(mddev), orig_id, sb_id); + + mddev->bitmap_id = sb_id; + if (!mddev_set_bitmap_ops(mddev)) { + mddev->bitmap_id = orig_id; + return -ENOENT; + } + + err = mddev->bitmap_ops->create(mddev); + if (err) { + mddev_clear_bitmap_ops(mddev); + mddev->bitmap_id = orig_id; + } + + return err; } static void md_bitmap_destroy(struct mddev *mddev) -- 2.53.0