From patchwork Sat Aug 20 11:51:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Pali_Roh=C3=A1r?= X-Patchwork-Id: 12949630 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 B1E95C25B08 for ; Sat, 20 Aug 2022 11:51:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345729AbiHTLvd (ORCPT ); Sat, 20 Aug 2022 07:51:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42912 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345327AbiHTLvc (ORCPT ); Sat, 20 Aug 2022 07:51:32 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 509C39E136; Sat, 20 Aug 2022 04:51:31 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 12225B8013A; Sat, 20 Aug 2022 11:51:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 44D6AC433D6; Sat, 20 Aug 2022 11:51:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1660996288; bh=Vj6nj5sawIYuwYfgAEZmjkahlR/5Zp1Ma3yQSqvSWjs=; h=From:To:Cc:Subject:Date:From; b=iFY0nygdd6IAogWPWqKWP5XoqHCJ5azIpvjhO+zIuIQuLJVxXV3+Xo5GvNceWRjtf rU4k4V1JSwG677uBGHnLtI1rFPjw+dIH6rk3/7RZEgciXvCJP9/3P38M5iy420Kn13 15lu9c3h/at5oPvOmG3Qwr22zNDd/4CFqpfI0VMDTMLOooYHVBYHwKYxISPCPRgrm/ oJr1Btx10CaTL8bzRpjQkkmvf5ybGr9FHtBZLnrvwMOTYgybcqsEI0JpUYVDRfl0xA H7oxMGuSgRwjwjiORdzM+7RAO48Mg8a5c7EZF7zGTgdoJSITwE5a6Xh7zuqYmO0AUT o5V/b3Q0xEs+g== Received: by pali.im (Postfix) id 7040E5D0; Sat, 20 Aug 2022 13:51:25 +0200 (CEST) From: =?utf-8?q?Pali_Roh=C3=A1r?= To: Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras Cc: linuxppc-dev@lists.ozlabs.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] powerpc/pci: Enable PCI domains in /proc when PCI bus numbers are not unique Date: Sat, 20 Aug 2022 13:51:13 +0200 Message-Id: <20220820115113.30581-1-pali@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On 32-bit powerpc systems with more PCIe controllers and more PCI domains, where on more PCI domains are same PCI numbers, when kernel is compiled with CONFIG_PROC_FS=y and CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT=y options, kernel prints "proc_dir_entry 'pci/01' already registered" error message. [ 1.708861] ------------[ cut here ]------------ [ 1.713429] proc_dir_entry 'pci/01' already registered [ 1.718595] WARNING: CPU: 0 PID: 1 at fs/proc/generic.c:377 proc_register+0x1a8/0x1ac [ 1.726361] Modules linked in: [ 1.729404] CPU: 0 PID: 1 Comm: swapper/0 Tainted: G W 5.19.0-rc5-0caacb197b677410bdac81bc34f05235+ #109 [ 1.740183] NIP: c02846e8 LR: c02846e8 CTR: c0015154 [ 1.745225] REGS: c146fc90 TRAP: 0700 Tainted: G W (5.19.0-rc5-0caacb197b677410bdac81bc34f05235+) [ 1.755657] MSR: 00029000 CR: 28000822 XER: 00000000 [ 1.761829] [ 1.761829] GPR00: c02846e8 c146fd80 c14a8000 0000002a 3fffefff c146fc40 c146fc38 00000000 [ 1.761829] GPR08: 3fffefff 00000000 00000000 c10ac04c 24000824 00000000 c0004548 00000000 [ 1.761829] GPR16: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000007 [ 1.761829] GPR24: c10000d0 c167da54 c167da00 c1120000 c167dd6c c10b4abc c167dc58 c167dd00 [ 1.796707] NIP [c02846e8] proc_register+0x1a8/0x1ac [ 1.801663] LR [c02846e8] proc_register+0x1a8/0x1ac [ 1.806532] Call Trace: [ 1.808966] [c146fd80] [c02846e8] proc_register+0x1a8/0x1ac (unreliable) [ 1.815659] [c146fdb0] [c028481c] _proc_mkdir+0x78/0xa4 [ 1.820875] [c146fdd0] [c05a92e4] pci_proc_attach_device+0x11c/0x168 [ 1.827221] [c146fe10] [c101f7a4] pci_proc_init+0x80/0x98 [ 1.832611] [c146fe30] [c0004150] do_one_initcall+0x80/0x284 [ 1.838262] [c146fea0] [c10011a8] kernel_init_freeable+0x1f4/0x2a0 [ 1.844434] [c146fee0] [c000456c] kernel_init+0x24/0x150 [ 1.849737] [c146ff00] [c001326c] ret_from_kernel_thread+0x5c/0x64 [ 1.855910] Instruction dump: [ 1.858866] 83810020 83a10024 83c10028 83e1002c 38210030 4e800020 809a0064 3c60c0a8 [ 1.866602] 7f85e378 3863af28 4cc63182 4bdb8155 <0fe00000> 9421ffe0 39200000 7c0802a6 [ 1.874513] ---[ end trace 0000000000000000 ]--- This regression started appearing after commit 566356813082 ("powerpc/pci: Add config option for using all 256 PCI buses") in case in each mPCIe slot is connected PCIe card and therefore PCI bus 1 is populated in for every PCIe controller / PCI domain. The reason is that PCI procfs code expects that when PCI bus numbers are not unique across all PCI domains, function pci_proc_domain() returns true for domain dependent buses. Fix this issue by setting PCI_ENABLE_PROC_DOMAINS and PCI_COMPAT_DOMAIN_0 flags for 32-bit powerpc code when CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT is enabled. Same approach is already implemented for 64-bit powerpc code (where PCI bus numbers are always domain dependent). Fixes: 566356813082 ("powerpc/pci: Add config option for using all 256 PCI buses") Signed-off-by: Pali Rohár --- arch/powerpc/kernel/pci_32.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/powerpc/kernel/pci_32.c b/arch/powerpc/kernel/pci_32.c index ffc4e1928c80..8acbc9592ebb 100644 --- a/arch/powerpc/kernel/pci_32.c +++ b/arch/powerpc/kernel/pci_32.c @@ -249,6 +249,15 @@ static int __init pcibios_init(void) printk(KERN_INFO "PCI: Probing PCI hardware\n"); +#ifdef CONFIG_PPC_PCI_BUS_NUM_DOMAIN_DEPENDENT + /* + * Enable PCI domains in /proc when PCI bus numbers are not unique + * across all PCI domains to prevent conflicts. And keep PCI domain 0 + * backward compatible in /proc for video cards. + */ + pci_add_flags(PCI_ENABLE_PROC_DOMAINS | PCI_COMPAT_DOMAIN_0); +#endif + if (pci_has_flag(PCI_REASSIGN_ALL_BUS)) pci_assign_all_buses = 1;