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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4E74CC54FB9 for ; Sat, 18 Nov 2023 11:59:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229700AbjKRL7d (ORCPT ); Sat, 18 Nov 2023 06:59:33 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229510AbjKRL7c (ORCPT ); Sat, 18 Nov 2023 06:59:32 -0500 Received: from mail-pg1-f198.google.com (mail-pg1-f198.google.com [209.85.215.198]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 01362E0 for ; Sat, 18 Nov 2023 03:59:28 -0800 (PST) Received: by mail-pg1-f198.google.com with SMTP id 41be03b00d2f7-5c17cff57f9so3153546a12.0 for ; Sat, 18 Nov 2023 03:59:28 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700308768; x=1700913568; h=to:from:subject:message-id:in-reply-to:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=d5cvEyP9e5+539SPTpJVNjpYxSJw1r+zQ1Jb6FbCprY=; b=XIw1hoLfzkWnPeasWLgYePz0uXKZFB9sAlkn/dzoTrSpVPRFe00TwyiXBeYKogURUz DadAzlQbDLVOV973lNX8rcv/9PbuRk4gxpCCY7wtK93Uae9bl0lcMhQpiOG252vAvfOg PCMOLAnxAautzolstvzOEzKCTGSRgz24IBTxmpq/lSuAjE+PgaWtJrYEEpYn2g0//W1K sJHFSAzSRimsWOOMD1qqgxNmsw2o65fKRLVeUIplwi/uSWVmTkcC2dkUYgOvZSOMMhDh dYK4e4JLLAuylrPpJJSmrlM/I+GhYXtkra0srddTJ2XC+vN8QKuwDeETGIsiq6ymkAjT gGtQ== X-Gm-Message-State: AOJu0YyWQD7/9pUIrlKA2OL/+kZjLFzfzaJf+Irb/SBCuqND6Nm8hVW+ vHEYE3KU0brZqxt7hy508lbrv1tmHoFA+gO9G6i0GhPrjx1Gi5w= X-Google-Smtp-Source: AGHT+IGb59x5K9AxPxE33MHw08zqL4ZqV6KyzwP2E3pCpNWIrOUWao3HhR45r0enyH8SJqYrn/4aZy4HsC8+yZKe0DBfmKGSlDh1 MIME-Version: 1.0 X-Received: by 2002:a63:5c59:0:b0:5c2:1ffc:ffb9 with SMTP id n25-20020a635c59000000b005c21ffcffb9mr333746pgm.5.1700308768564; Sat, 18 Nov 2023 03:59:28 -0800 (PST) Date: Sat, 18 Nov 2023 03:59:28 -0800 In-Reply-To: <000000000000bf0b1f060a2d9bea@google.com> X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <00000000000028ab9d060a6bfcf2@google.com> Subject: Re: [syzbot] [PATCH] Test divide err in drm From: syzbot To: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For archival purposes, forwarding an incoming command email to linux-kernel@vger.kernel.org. *** Subject: [PATCH] Test divide err in drm Author: eadavis@qq.com please test divide err in drm #syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git ac347a0655db diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c index ac9a406250c5..539aa26cfc72 100644 --- a/drivers/gpu/drm/drm_modes.c +++ b/drivers/gpu/drm/drm_modes.c @@ -1285,7 +1285,8 @@ EXPORT_SYMBOL(drm_mode_set_name); */ int drm_mode_vrefresh(const struct drm_display_mode *mode) { - unsigned int num, den; + unsigned int num, den, n1k; + int ret; if (mode->htotal == 0 || mode->vtotal == 0) return 0; @@ -1297,9 +1298,17 @@ int drm_mode_vrefresh(const struct drm_display_mode *mode) num *= 2; if (mode->flags & DRM_MODE_FLAG_DBLSCAN) den *= 2; - if (mode->vscan > 1) - den *= mode->vscan; + n1k = mul_u32_u32(num, 1000); + if (mode->vscan > 1) { + if (den < n1k) + den *= mode->vscan; + } + if (den < n1k) + den = n1k + 1; + ret = DIV_ROUND_CLOSEST_ULL(mul_u32_u32(num, 1000), den); + printk("mode: %p, ht: %d, vt: %d, c: %d, vsc: %d, den: %ld, num: %ld, n1k: %ld, %d, %s", + mode, mode->htotal, mode->vtotal, mode->clock, mode->vscan, den, num, n1k, ret, __func__); return DIV_ROUND_CLOSEST_ULL(mul_u32_u32(num, 1000), den); } EXPORT_SYMBOL(drm_mode_vrefresh);