From patchwork Wed Jan 3 03:19:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kai-Heng Feng X-Patchwork-Id: 1881855 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ubuntu.com (client-ip=185.125.189.65; helo=lists.ubuntu.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=patchwork.ozlabs.org) Received: from lists.ubuntu.com (lists.ubuntu.com [185.125.189.65]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4T4Zhh0Nvkz23d9 for ; Wed, 3 Jan 2024 14:19:47 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=lists.ubuntu.com) by lists.ubuntu.com with esmtp (Exim 4.86_2) (envelope-from ) id 1rKrmy-0000mH-WD; Wed, 03 Jan 2024 03:19:29 +0000 Received: from smtp-relay-canonical-1.internal ([10.131.114.174] helo=smtp-relay-canonical-1.canonical.com) by lists.ubuntu.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1rKrmu-0000le-Ck for kernel-team@lists.ubuntu.com; Wed, 03 Jan 2024 03:19:25 +0000 Received: from HP-EliteBook-x360-830-G8-Notebook-PC.. (unknown [10.101.196.174]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-1.canonical.com (Postfix) with ESMTPSA id 293493F6BC for ; Wed, 3 Jan 2024 03:19:21 +0000 (UTC) From: Kai-Heng Feng To: kernel-team@lists.ubuntu.com Subject: [M/N] [PATCH] wifi: iwlwifi: pcie: rescan bus if no parent Date: Wed, 3 Jan 2024 11:19:16 +0800 Message-Id: <20240103031916.782306-3-kai.heng.feng@canonical.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240103031916.782306-1-kai.heng.feng@canonical.com> References: <20240103031916.782306-1-kai.heng.feng@canonical.com> MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" From: Johannes Berg BugLink: https://bugs.launchpad.net/bugs/2046217 If the bus has no parent due to the topology, the device rescan (after some kind of reset was detected) wouldn't work. On the other hand, some platforms appear to require scanning the parent, though it's not clear why. However if there's no parent, then we skip the rescan, which isn't a good idea. Change the code to go to the parent only if that exists, and rescan the bus itself where it doesn't. Signed-off-by: Johannes Berg Signed-off-by: Gregory Greenman Link: https://lore.kernel.org/r/20230913145231.f7795a1ccdab.I2b84810a743469a1bcabf3628262cf54311593f4@changeid Signed-off-by: Johannes Berg (cherry picked from commit 111ed1eb175754a9ef11811240329ca40db2072f) Signed-off-by: Kai-Heng Feng --- drivers/net/wireless/intel/iwlwifi/pcie/trans.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c index 583d1011963e..86f6cb5af691 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c @@ -2113,8 +2113,11 @@ static void iwl_trans_pcie_removal_wk(struct work_struct *wk) pci_lock_rescan_remove(); pci_dev_put(pdev); pci_stop_and_remove_bus_device(pdev); - if (removal->rescan) - pci_rescan_bus(bus->parent); + if (removal->rescan && bus) { + if (bus->parent) + bus = bus->parent; + pci_rescan_bus(bus); + } pci_unlock_rescan_remove(); kfree(removal);