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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B291BC3DA64 for ; Thu, 1 Aug 2024 00:36:13 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=XYQx16om; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4WZ94X1KXvz3dC5 for ; Thu, 1 Aug 2024 10:36:12 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=XYQx16om; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=139.178.84.217; helo=dfw.source.kernel.org; envelope-from=sashal@kernel.org; receiver=lists.ozlabs.org) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) (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 4WZ93m34Qcz2y8m for ; Thu, 1 Aug 2024 10:35:32 +1000 (AEST) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 8334962551; Thu, 1 Aug 2024 00:35:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0963FC4AF0E; Thu, 1 Aug 2024 00:35:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722472530; bh=Lp/CkH9sWC8WcDgHAMzi3z91a5u20XsSX+ogEhcdnHo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XYQx16omu0xWhRkPSGksPfM8jtB2E8IUFsZE2b++hn7UMuiHis4yCUWuYbIsyeCPm 5477vrmXqTwCnW+p14amOx45OMfkcamNJBnNOEHRcdnb221g4VDVbcSLNA/Y4i7qyX sh5SuYQCT7RtSIhsmn8Pjp5kHyRiJ3piBT2ZvtDZPbrgQVPJYF1ebC6qbK1oFg31J3 YFrK+/uhxnitfqhamf0UoQPDvveEg0EoVXZDRXo5mpe0fjCWYF/u+XQAbd6LadckmK Y0q85Aw7drHNvEZQ8pSFpX+wsko6M7HX43LWLwhDJZlQJ4RDPXj+kyhLSsgKZAG8gu 1m3MDC2F+xAHQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.15 42/47] pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv Date: Wed, 31 Jul 2024 20:31:32 -0400 Message-ID: <20240801003256.3937416-42-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240801003256.3937416-1-sashal@kernel.org> References: <20240801003256.3937416-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.15.164 Content-Transfer-Encoding: 8bit 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: Sasha Levin , Shawn Anastasio , Bjorn Helgaas , Timothy Pearson , linux-pci@vger.kernel.org, Krishna Kumar , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Krishna Kumar [ Upstream commit 335e35b748527f0c06ded9eebb65387f60647fda ] The hotplug driver for powerpc (pci/hotplug/pnv_php.c) causes a kernel crash when we try to hot-unplug/disable the PCIe switch/bridge from the PHB. The crash occurs because although the MSI data structure has been released during disable/hot-unplug path and it has been assigned with NULL, still during unregistration the code was again trying to explicitly disable the MSI which causes the NULL pointer dereference and kernel crash. The patch fixes the check during unregistration path to prevent invoking pci_disable_msi/msix() since its data structure is already freed. Reported-by: Timothy Pearson Closes: https://lore.kernel.org/all/1981605666.2142272.1703742465927.JavaMail.zimbra@raptorengineeringinc.com/ Acked-by: Bjorn Helgaas Tested-by: Shawn Anastasio Signed-off-by: Krishna Kumar Signed-off-by: Michael Ellerman Link: https://msgid.link/20240701074513.94873-2-krishnak@linux.ibm.com Signed-off-by: Sasha Levin --- drivers/pci/hotplug/pnv_php.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c index f4c2e6e01be04..e233f8402e8cc 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -38,7 +38,6 @@ static void pnv_php_disable_irq(struct pnv_php_slot *php_slot, bool disable_device) { struct pci_dev *pdev = php_slot->pdev; - int irq = php_slot->irq; u16 ctrl; if (php_slot->irq > 0) { @@ -57,7 +56,7 @@ static void pnv_php_disable_irq(struct pnv_php_slot *php_slot, php_slot->wq = NULL; } - if (disable_device || irq > 0) { + if (disable_device) { if (pdev->msix_enabled) pci_disable_msix(pdev); else if (pdev->msi_enabled) -- 2.43.0