From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9B88F1DE0DB; Thu, 1 Aug 2024 00:35:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722472530; cv=none; b=aGvcyACA2LZHeN4pZ2v+eWmJK94CSeL/KmK8tY3Mc8L6duPP4vrn5cMY1yb6viEzabTF5oZP3mZKJB338tohQJBPNpuj6MySMeSGY2sFs+aUGjKAX3DCaR40kFZ2dS3LFqzlCPVM8WBrWoq2nitiAZB0voArIpLj4kSzGyPDKFw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722472530; c=relaxed/simple; bh=Lp/CkH9sWC8WcDgHAMzi3z91a5u20XsSX+ogEhcdnHo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pX23Nnwn9lMIUd3VFHHYEqz0zp7AM09COKpgNtxVImc3EJXR3mI0qvCO+OQ4wjVDniI1KpPHXSOK1HFxrZw88Niqxo4aXCboeTWSm5rdFBx/hmHcVG30RS5ZfC3a23GfV77cn+773V4NraZeD7Ip5Ey50HHSlC/X6r3FQYj8E+Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XYQx16om; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="XYQx16om" 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 Cc: Krishna Kumar , Timothy Pearson , Bjorn Helgaas , Shawn Anastasio , Michael Ellerman , Sasha Levin , linuxppc-dev@lists.ozlabs.org, linux-pci@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> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 5.15.164 Content-Transfer-Encoding: 8bit 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