From patchwork Thu Sep 28 06:15:19 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Kuai X-Patchwork-Id: 13401991 X-Patchwork-Delegate: song@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8EED6CE7AFD for ; Thu, 28 Sep 2023 06:22:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230304AbjI1GWD (ORCPT ); Thu, 28 Sep 2023 02:22:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230220AbjI1GWB (ORCPT ); Thu, 28 Sep 2023 02:22:01 -0400 Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6569DA3; Wed, 27 Sep 2023 23:21:59 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4Rx3Kb4TFxz4f3jZR; Thu, 28 Sep 2023 14:21:55 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.104.67]) by APP4 (Coremail) with SMTP id gCh0CgAnvdyCGxVl3v1WBg--.22861S5; Thu, 28 Sep 2023 14:21:56 +0800 (CST) From: Yu Kuai To: xni@redhat.com, agk@redhat.com, snitzer@kernel.org, dm-devel@redhat.com, song@kernel.org Cc: linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org, yukuai3@huawei.com, yukuai1@huaweicloud.com, yi.zhang@huawei.com, yangerkun@huawei.com Subject: [PATCH -next v3 01/25] md: use READ_ONCE/WRITE_ONCE for 'suspend_lo' and 'suspend_hi' Date: Thu, 28 Sep 2023 14:15:19 +0800 Message-Id: <20230928061543.1845742-2-yukuai1@huaweicloud.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230928061543.1845742-1-yukuai1@huaweicloud.com> References: <20230928061543.1845742-1-yukuai1@huaweicloud.com> MIME-Version: 1.0 X-CM-TRANSID: gCh0CgAnvdyCGxVl3v1WBg--.22861S5 X-Coremail-Antispam: 1UD129KBjvJXoW7CF4fAw13JF4xAF18Kw43trb_yoW8tw4rp3 yIqFWYgr45tas5AryUt3WkCFy5XwsxKrWqyrZrWryUG3W7Gw1rGr15XF43XryFvas3CFsx Gws8A3W8A348GFUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBE14x267AKxVW5JVWrJwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_Jr4l82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_tr0E3s1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr1j6F4UJw A2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAS 0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2 IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628vn2kIc2 xKxwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v2 6r1j6r18MI8I3I0E7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2 Ij64vIr41lIxAIcVC0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_ Gr0_Cr1lIxAIcVCF04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMI IF0xvEx4A2jsIEc7CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JU2_M3UUUUU = X-CM-SenderInfo: 51xn3trlr6x35dzhxuhorxvhhfrp/ X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org From: Yu Kuai Because reading 'suspend_lo' and 'suspend_hi' from md_handle_request() is not protected, use READ_ONCE/WRITE_ONCE to prevent reading abnormal value. Signed-off-by: Yu Kuai --- drivers/md/md.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 0b83a406e797..18a0f12dbf5f 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -359,11 +359,11 @@ static bool is_suspended(struct mddev *mddev, struct bio *bio) return true; if (bio_data_dir(bio) != WRITE) return false; - if (mddev->suspend_lo >= mddev->suspend_hi) + if (READ_ONCE(mddev->suspend_lo) >= READ_ONCE(mddev->suspend_hi)) return false; - if (bio->bi_iter.bi_sector >= mddev->suspend_hi) + if (bio->bi_iter.bi_sector >= READ_ONCE(mddev->suspend_hi)) return false; - if (bio_end_sector(bio) < mddev->suspend_lo) + if (bio_end_sector(bio) < READ_ONCE(mddev->suspend_lo)) return false; return true; } @@ -5176,7 +5176,8 @@ __ATTR(sync_max, S_IRUGO|S_IWUSR, max_sync_show, max_sync_store); static ssize_t suspend_lo_show(struct mddev *mddev, char *page) { - return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_lo); + return sprintf(page, "%llu\n", + (unsigned long long)READ_ONCE(mddev->suspend_lo)); } static ssize_t @@ -5196,7 +5197,7 @@ suspend_lo_store(struct mddev *mddev, const char *buf, size_t len) return err; mddev_suspend(mddev); - mddev->suspend_lo = new; + WRITE_ONCE(mddev->suspend_lo, new); mddev_resume(mddev); mddev_unlock(mddev); @@ -5208,7 +5209,8 @@ __ATTR(suspend_lo, S_IRUGO|S_IWUSR, suspend_lo_show, suspend_lo_store); static ssize_t suspend_hi_show(struct mddev *mddev, char *page) { - return sprintf(page, "%llu\n", (unsigned long long)mddev->suspend_hi); + return sprintf(page, "%llu\n", + (unsigned long long)READ_ONCE(mddev->suspend_hi)); } static ssize_t @@ -5228,7 +5230,7 @@ suspend_hi_store(struct mddev *mddev, const char *buf, size_t len) return err; mddev_suspend(mddev); - mddev->suspend_hi = new; + WRITE_ONCE(mddev->suspend_hi, new); mddev_resume(mddev); mddev_unlock(mddev);