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 5C543C54EBE for ; Mon, 16 Jan 2023 12:16:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229799AbjAPMQJ (ORCPT ); Mon, 16 Jan 2023 07:16:09 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229517AbjAPMQG (ORCPT ); Mon, 16 Jan 2023 07:16:06 -0500 X-Greylist: delayed 576 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Mon, 16 Jan 2023 04:16:01 PST Received: from smtp-out-07.comm2000.it (smtp-out-07.comm2000.it [212.97.32.77]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FF3E270C; Mon, 16 Jan 2023 04:16:01 -0800 (PST) Received: from francesco-nb.int.toradex.com (31-10-206-125.static.upc.ch [31.10.206.125]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: francesco@dolcini.it) by smtp-out-07.comm2000.it (Postfix) with ESMTPSA id CF6653C2901; Mon, 16 Jan 2023 13:06:23 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=mailserver.it; s=mailsrv; t=1673870784; bh=ww3wNkm2WTEAwlFgREQLZhocFDwbXyOXH1fBRgEgaL4=; h=Date:From:To:Cc:Subject; b=uXGcYwb3+5pn9KIDDhsxnjBf1hJEeDy+YDO0map1xvvdCpieM+o5ZrUseMm2V+eWo ZOY1l2NA2mQJuaSP27Z14/JNzRXKOsJjBLTAQ0QqYa1WaKQ+Tr4NOtg3adl2ty1bP3 TX9iyKW+t63ZsCqENFs/YXqcCKAnbvIViqH6xDYj2MBXQiAHCxKAJ/J0O14sycRQFD k18kGoEZGFr4Kah6SZ2AYOJ6JZfFCCs5BIluvej07r1z5yHKvu/90gTZwt74hp0fPe AMUEUGHA7k0brU8u9ov16M1+ETCbq9HC3uUVplwZJhpM6x2vMO20MZvJfp8mwTUDsQ ZhuCWvfo+I+ug== Date: Mon, 16 Jan 2023 13:06:22 +0100 From: Francesco Dolcini To: Bartosz Golaszewski , Mark Brown , bartosz.golaszewski@linaro.org Cc: linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, max.krummenacher@toradex.com Subject: spidev regression in 6.2-rc kernel Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, we spotted a regression on spidev on latest 6.2-rc kernel. [ 214.047619] [ 214.049198] ============================================ [ 214.054533] WARNING: possible recursive locking detected [ 214.059858] 6.2.0-rc3-0.0.0-devel+git.97ec4d559d93 #1 Not tainted [ 214.065969] -------------------------------------------- [ 214.071290] spidev_test/1454 is trying to acquire lock: [ 214.076530] c4925dbc (&spidev->spi_lock){+.+.}-{3:3}, at: spidev_ioctl+0x8e0/0xab8 [ 214.084164] [ 214.084164] but task is already holding lock: [ 214.090007] c4925dbc (&spidev->spi_lock){+.+.}-{3:3}, at: spidev_ioctl+0x44/0xab8 [ 214.097537] [ 214.097537] other info that might help us debug this: [ 214.104075] Possible unsafe locking scenario: [ 214.104075] [ 214.110004] CPU0 [ 214.112461] ---- [ 214.114916] lock(&spidev->spi_lock); [ 214.118687] lock(&spidev->spi_lock); [ 214.122457] [ 214.122457] *** DEADLOCK *** [ 214.122457] [ 214.128386] May be due to missing lock nesting notation [ 214.128386] [ 214.135183] 2 locks held by spidev_test/1454: [ 214.139553] #0: c4925dbc (&spidev->spi_lock){+.+.}-{3:3}, at: spidev_ioctl+0x44/0xab8 [ 214.147524] #1: c4925e14 (&spidev->buf_lock){+.+.}-{3:3}, at: spidev_ioctl+0x70/0xab8 [ 214.155493] [ 214.155493] stack backtrace: [ 214.159861] CPU: 0 PID: 1454 Comm: spidev_test Not tainted 6.2.0-rc3-0.0.0-devel+git.97ec4d559d93 #1 [ 214.169012] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree) [ 214.175555] unwind_backtrace from show_stack+0x10/0x14 [ 214.180819] show_stack from dump_stack_lvl+0x60/0x90 [ 214.185900] dump_stack_lvl from __lock_acquire+0x874/0x2858 [ 214.191584] __lock_acquire from lock_acquire+0xfc/0x378 [ 214.196918] lock_acquire from __mutex_lock+0x9c/0x8a8 [ 214.202083] __mutex_lock from mutex_lock_nested+0x1c/0x24 [ 214.207597] mutex_lock_nested from spidev_ioctl+0x8e0/0xab8 [ 214.213284] spidev_ioctl from sys_ioctl+0x4d0/0xe2c [ 214.218277] sys_ioctl from ret_fast_syscall+0x0/0x1c [ 214.223351] Exception stack(0xe75cdfa8 to 0xe75cdff0) [ 214.228422] dfa0: 00000000 00001000 00000003 40206b00 bee266e8 bee266e0 [ 214.236617] dfc0: 00000000 00001000 006a71a0 00000036 004c0040 004bfd18 00000000 00000003 [ 214.244809] dfe0: 00000036 bee266c8 b6f16dc5 b6e8e5f6 This is not running the latest rc4, but on sha 97ec4d559d93 (this is just what our CI had available when this test was run). I was not able to bisect it, but it seems something that you could have introduced. The log is from an apalis-imx6, but I have the same on other ARM SOC. Can you have a look? Thanks Francesco