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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham 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 D0C4BC282C7 for ; Tue, 29 Jan 2019 03:27:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8E663214DA for ; Tue, 29 Jan 2019 03:27:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727128AbfA2D1r (ORCPT ); Mon, 28 Jan 2019 22:27:47 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:53074 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727041AbfA2D1q (ORCPT ); Mon, 28 Jan 2019 22:27:46 -0500 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 3E4D7C1DFBDAE7BD24C4; Tue, 29 Jan 2019 11:27:45 +0800 (CST) Received: from [127.0.0.1] (10.177.219.49) by DGGEMS412-HUB.china.huawei.com (10.3.19.212) with Microsoft SMTP Server id 14.3.408.0; Tue, 29 Jan 2019 11:27:42 +0800 Subject: Re: [PATCH] floppy: check_events callback should not return a negative number To: Dan Carpenter CC: , , , References: <20190128090646.44747-1-yuyufen@huawei.com> <20190128131942.GH1795@kadam> From: yuyufen Message-ID: <0c53dcac-94db-a8a7-addf-673c29abe068@huawei.com> Date: Tue, 29 Jan 2019 11:27:23 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20190128131942.GH1795@kadam> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Originating-IP: [10.177.219.49] X-CFilter-Loop: Reflected Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 2019/1/28 21:19, Dan Carpenter wrote: > On Mon, Jan 28, 2019 at 05:06:46PM +0800, Yufen Yu wrote: >> Since .check_events interface return an unsigned int value, >> floppy_check_events() should not return a negative error number. >> Otherwise, disk_check_events() may process wiht an unexpected path. >> >> fixes: a0c80efe5956 ("floppy: fix lock_fdc() signal handling") >> Signed-off-by: Yufen Yu >> --- >> drivers/block/floppy.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c >> index 6f2856c6d0f2..55481b40df9a 100644 >> --- a/drivers/block/floppy.c >> +++ b/drivers/block/floppy.c >> @@ -4075,7 +4075,7 @@ static unsigned int floppy_check_events(struct gendisk *disk, >> >> if (time_after(jiffies, UDRS->last_checked + UDP->checkfreq)) { >> if (lock_fdc(drive)) >> - return -EINTR; >> + return 0; > The patch is correct, but I wish the commit message had said what the > run time impact of the patch is. Or sometimes it's hard to say what the > run time impact is, but it could have at least said why returning zero > is correct. Say something like: > > floppy_check_events() is supposed to return bit flags to say which > events occured. We should return zero to say that no event flags are > set. Only BIT(0) and BIT(1) are used in the caller. This code > returns -4u here so both BIT(0) and BIT(1) are clear. So this patch > shouldn't affect runtime, but it obviously is still worth fixing. OK. Thanks a lot for your suggestion. thanks, Yufen > regards, > dan carpenter > > . >