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=-10.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 AA153C433E1 for ; Thu, 30 Jul 2020 01:31:12 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 27C1920809 for ; Thu, 30 Jul 2020 01:31:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ellerman.id.au header.i=@ellerman.id.au header.b="Jmc6e8k7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 27C1920809 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4BHCY95sc2zDqtR for ; Thu, 30 Jul 2020 11:31:09 +1000 (AEST) Received: from ozlabs.org (bilbo.ozlabs.org [IPv6:2401:3900:2:1::2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4BHCVL5J3jzDqdf for ; Thu, 30 Jul 2020 11:28:42 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ellerman.id.au Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=ellerman.id.au header.i=@ellerman.id.au header.a=rsa-sha256 header.s=201909 header.b=Jmc6e8k7; dkim-atps=neutral Received: from authenticated.ozlabs.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mail.ozlabs.org (Postfix) with ESMTPSA id 4BHCVL0ZHZz9sRN; Thu, 30 Jul 2020 11:28:41 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ellerman.id.au; s=201909; t=1596072522; bh=CBXQEncx5ICdSQp2iEa2IBvBCwHWDKYPRESmYradVyQ=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=Jmc6e8k7CX0FVJeMzy9n7A0qudqL+MWV/ykUBtaYD3TnFW9axvLLnjlCbcK+U2GA/ UwiO/+Trw1tQuZ2LwdXFXR/ZOgkI8xBpJnSw4p7M5y9olADT0z2C1AbGYOrgyFc/pc OVroqo8DO25h3Bi3tPFoPtkvlj+E6SC5Sckbly6IHnOlUnVU82+QPZH0MCW0HOapnA g9qjIU7i6xkGQmMOtm8Icu31QiCs5UmIsFu1geEZ+tUvBPMu68eQWTvfFaqwcvfhLJ DqLvDQYN8N27W6Y4Zx9aakeLgfDoVwtMybaXGXXZjwuL2+HLM9jDlvOtuwPlPxPIuI kpCTZ392OLEFQ== From: Michael Ellerman To: Thadeu Lima de Souza Cascardo , linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH v2] powerpc/vio: drop bus_type from parent device In-Reply-To: <20200406155748.6761-1-cascardo@canonical.com> References: <20200406155748.6761-1-cascardo@canonical.com> Date: Thu, 30 Jul 2020 11:28:38 +1000 Message-ID: <87ime56bax.fsf@mpe.ellerman.id.au> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: cascardo@canonical.com, Peter Rajnoha , gregkh@linuxfoundation.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" [ Added Peter & Greg to Cc ] Thadeu Lima de Souza Cascardo writes: > Commit df44b479654f62b478c18ee4d8bc4e9f897a9844 ("kobject: return error > code if writing /sys/.../uevent fails") started returning failure when > writing to /sys/devices/vio/uevent. > > This causes an early udevadm trigger to fail. On some installer versions of > Ubuntu, this will cause init to exit, thus panicing the system very early > during boot. > > Removing the bus_type from the parent device will remove some of the extra > empty files from /sys/devices/vio/, but will keep the rest of the layout > for vio devices, keeping them under /sys/devices/vio/. What exactly does it change? I'm finding it hard to evaluate if this change is going to cause a regression somehow. I'm also not clear on why removing the bus type is correct, apart from whether it fixes the bug you're seeing. > It has been tested that uevents for vio devices don't change after this > fix, they still contain MODALIAS. > > Signed-off-by: Thadeu Lima de Souza Cascardo > Fixes: df44b479654f ("kobject: return error code if writing /sys/.../uevent fails") AFAICS there haven't been any other fixes for that commit. Do we know why it is only vio that was affected? (possibly because it's a fake bus to begin with?) cheers > diff --git a/arch/powerpc/platforms/pseries/vio.c b/arch/powerpc/platforms/pseries/vio.c > index 37f1f25ba804..a94dab3972a0 100644 > --- a/arch/powerpc/platforms/pseries/vio.c > +++ b/arch/powerpc/platforms/pseries/vio.c > @@ -36,7 +36,6 @@ static struct vio_dev vio_bus_device = { /* fake "parent" device */ > .name = "vio", > .type = "", > .dev.init_name = "vio", > - .dev.bus = &vio_bus_type, > }; > > #ifdef CONFIG_PPC_SMLPAR > -- > 2.20.1