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 D1ED4C32772 for ; Tue, 23 Aug 2022 15:47:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243865AbiHWPrH (ORCPT ); Tue, 23 Aug 2022 11:47:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43238 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243751AbiHWPqv (ORCPT ); Tue, 23 Aug 2022 11:46:51 -0400 Received: from smtp-out1.suse.de (smtp-out1.suse.de [IPv6:2001:67c:2178:6::1c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 71CE02AB3C2 for ; Tue, 23 Aug 2022 04:47:08 -0700 (PDT) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id F3E5A2249F; Tue, 23 Aug 2022 11:46:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1661255197; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=9o5iSdVTRwCUBgwkGJPpuGhtLCLbWfRwPX9fK6q7WKU=; b=oQtudiJdms3SmnDi5sa5DnPCU57m9UeixY3Xdmh1Mlfw9rwYTdx/Y8QmKWs3oKC2JvuWoT v4zGdfNnP4hGJSv0n8/1oiWEN/6i74OzjzaMI0EMmx4XlhxIjoqET9pLqPB2WWfet49QZ2 J4iy10FMb+nwaopI+K2MZjLYls5WSHo= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1661255197; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=9o5iSdVTRwCUBgwkGJPpuGhtLCLbWfRwPX9fK6q7WKU=; b=e/lU9SYExuOuyeB4j/bQaW92vLIhHMDHPPo1CUTPDe64WM2ACKDI0pSDprkbVkVQB80aZ/ U4Ku1BAYIl5+jlCw== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id BA6D713AB7; Tue, 23 Aug 2022 11:46:36 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id ClWrLBy+BGOlMwAAMHmgww (envelope-from ); Tue, 23 Aug 2022 11:46:36 +0000 Date: Tue, 23 Aug 2022 13:46:36 +0200 Message-ID: <87ilmjqj1f.wl-tiwai@suse.de> From: Takashi Iwai To: Jason Gunthorpe Cc: Lu Baolu , Joerg Roedel , Greg Kroah-Hartman , Bjorn Helgaas , Robin Murphy , Eric Auger , regressions@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [REGRESSION 5.19.x] AMD HD-audio devices missing on 5.19 In-Reply-To: <87h723sdde.wl-tiwai@suse.de> References: <874jy4cqok.wl-tiwai@suse.de> <20220823010021.GA5967@nvidia.com> <87h723sdde.wl-tiwai@suse.de> User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/27.2 Mule/6.0 MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 23 Aug 2022 08:06:05 +0200, Takashi Iwai wrote: > > On Tue, 23 Aug 2022 03:00:21 +0200, > Jason Gunthorpe wrote: > > > > On Mon, Aug 22, 2022 at 04:12:59PM +0200, Takashi Iwai wrote: > > > Hi, > > > > > > we've received regression reports about the missing HD-audio devices > > > on AMD platforms, and this turned out to be caused by the commit > > > 512881eacfa72c2136b27b9934b7b27504a9efc2 > > > bus: platform,amba,fsl-mc,PCI: Add device DMA ownership management > > > > > > The details are found in openSUSE bugzilla: > > > https://bugzilla.suse.com/show_bug.cgi?id=1202492 > > > > > > The problem seems to be that HD-audio (both onboard analog and HDMI) > > > PCI devices are assigned to the same IOMMU group as AMD graphics PCI > > > device, and once after the AMDGPU is initialized beforehand, those > > > audio devices can't be probed since iommu_device_use_default_domain() > > > returns -EBUSY. > > > > Can you describe exactly what drivers are involved in this? If it is > > the above commit then several devices are sharing an iommu group and > > one of them (well, the only one already attached, I suppose) has made > > the group unsharable. > > > > With grep I don't see an obvious place where the AMDGPU driver would > > mess with the iommu configuration, so I have no guess. > > I have also no concrete clue, either :) > At least, drivers/gpu/drm/amd/amdkfd/kfd_iommu.c calls > amd_iommu_init_device(), and this invokes iommu_attach_group(), which > may change group->domain. But it was just my wild guess, and it might > be others, indeed. > > > It would be good to have some debugging to confirm if it is > > group->owner (should be impossible, suggests memory corruption if it > > is) or group->domain != group->default_domain. > > > > Most likely it is the later, but I can't see how that could happen on > > a system like this.. There is no obvious manipulation in AMDGPU, for > > instance. > > > > So debugging to find the backtrace for exactly when > > group->domain != group->default_domain > > Occurs for the troubled group would be necessary. > > OK, will try to build a test kernel with some debug prints and ask the > reporters. It may take some time. It was tested now and confirmed that the call path is via AMDGPU, as expected: amdgpu_pci_probe -> amdgpu_driver_load_kms -> amdgpu_device_init -> amdgpu_amdkfd_device_init -> kgd2kfd_device_init -> kgd2kfd_resume_iommu -> kfd_iommu_resume -> amd_iommu_init_device -> iommu_attach_group -> __iommu_attach_group At first AMDGPU driver is probed, and the iommu_attach_group() call above changes the assigned group->domain. Afterwards, when HD-audio devices are probed, it fails because: - Both HD-audio PCI devices belong to the very same IOMMU group as the AMD graphics PCI device - PCI core calls iommu_device_use_default_domain() and the check fails there because group->domain != group->default_domain Takashi