From patchwork Mon Jan 25 18:37:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 371309 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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 19732C433DB for ; Tue, 26 Jan 2021 21:09:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1CA822B2C for ; Tue, 26 Jan 2021 21:09:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728873AbhAZExU (ORCPT ); Mon, 25 Jan 2021 23:53:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:34004 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726759AbhAYSre (ORCPT ); Mon, 25 Jan 2021 13:47:34 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 59188224B8; Mon, 25 Jan 2021 18:47:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1611600427; bh=uHNVg1ZOxn4o7RXr91kFpduyISj09pE+619/H56nvKc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Wl7VWbDuZOYWr27qHn5OsZMEn01URlSF3ktUa6R0Z9g/WPgrJ9FJZgCeMH2ClcASL tpQfWkCZOv5OM+jwsLXoABOLR5XPxo3RSLkspf0oDBnbrpzqAqneL2LumzOhMSlvVd Ucwrs0bBP5yyIUz4C8AMmdpooBShq8vufUjxVO7w= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kirill Tkhai , Ard Biesheuvel , Herbert Xu Subject: [PATCH 5.10 011/199] crypto: xor - Fix divide error in do_xor_speed() Date: Mon, 25 Jan 2021 19:37:13 +0100 Message-Id: <20210125183216.734988547@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210125183216.245315437@linuxfoundation.org> References: <20210125183216.245315437@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kirill Tkhai commit 3c02e04fd4f57130e4fa75fab6f528f7a52db9b5 upstream. crypto: Fix divide error in do_xor_speed() From: Kirill Tkhai Latest (but not only latest) linux-next panics with divide error on my QEMU setup. The patch at the bottom of this message fixes the problem. xor: measuring software checksum speed divide error: 0000 [#1] PREEMPT SMP KASAN PREEMPT SMP KASAN CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.10.0-next-20201223+ #2177 RIP: 0010:do_xor_speed+0xbb/0xf3 Code: 41 ff cc 75 b5 bf 01 00 00 00 e8 3d 23 8b fe 65 8b 05 f6 49 83 7d 85 c0 75 05 e8 84 70 81 fe b8 00 00 50 c3 31 d2 48 8d 7b 10 f5 41 89 c4 e8 58 07 a2 fe 44 89 63 10 48 8d 7b 08 e8 cb 07 a2 RSP: 0000:ffff888100137dc8 EFLAGS: 00010246 RAX: 00000000c3500000 RBX: ffffffff823f0160 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000808 RDI: ffffffff823f0170 RBP: 0000000000000000 R08: ffffffff8109c50f R09: ffffffff824bb6f7 R10: fffffbfff04976de R11: 0000000000000001 R12: 0000000000000000 R13: ffff888101997000 R14: ffff888101994000 R15: ffffffff823f0178 FS: 0000000000000000(0000) GS:ffff8881f7780000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000220e000 CR4: 00000000000006a0 Call Trace: calibrate_xor_blocks+0x13c/0x1c4 ? do_xor_speed+0xf3/0xf3 do_one_initcall+0xc1/0x1b7 ? start_kernel+0x373/0x373 ? unpoison_range+0x3a/0x60 kernel_init_freeable+0x1dd/0x238 ? rest_init+0xc6/0xc6 kernel_init+0x8/0x10a ret_from_fork+0x1f/0x30 ---[ end trace 5bd3c1d0b77772da ]--- Fixes: c055e3eae0f1 ("crypto: xor - use ktime for template benchmarking") Cc: Signed-off-by: Kirill Tkhai Acked-by: Ard Biesheuvel Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman --- crypto/xor.c | 2 ++ 1 file changed, 2 insertions(+) --- a/crypto/xor.c +++ b/crypto/xor.c @@ -107,6 +107,8 @@ do_xor_speed(struct xor_block_template * preempt_enable(); // bytes/ns == GB/s, multiply by 1000 to get MB/s [not MiB/s] + if (!min) + min = 1; speed = (1000 * REPS * BENCH_SIZE) / (unsigned int)ktime_to_ns(min); tmpl->speed = speed;