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 0C9491B994E; Thu, 1 Aug 2024 00:31:23 +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=1722472283; cv=none; b=mSLyznUr5hiMPQRtfygSqEsBVbAMHtPIABLHl5YRWDAFTwTbzaImWqjHGs16Ljk1+1ZY6OK/tjZFrqp7bxDgDM4RA5b3YTP1da1vBwVp9X9P2XNlFKimjzY4NuzMmPbg98xcx51cpMOGULuhGyd4FMr9xIDi1pDv9OnY/nAua0U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722472283; c=relaxed/simple; bh=zG7zwTNzZpJGhl48N6vwkJx0GeMhonMcxgLMd8V2Fig=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XcipahvYeRO3aIBNMN/A1xb7612YTd9saAEiC3Y+rYdQB+0cMh+RaONtyC2RdaY6g1fCk1APNth8MYu5g9c4fjFA9clxdZTqALdfBkKSStRjowUEJXEYh4whnBDuO8kLh1Ayw2eV0eedwp+s7XcMxeahL9j/ngj+UoC5UTQPQD0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ElWT6Nge; 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="ElWT6Nge" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE0AEC32786; Thu, 1 Aug 2024 00:31:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722472282; bh=zG7zwTNzZpJGhl48N6vwkJx0GeMhonMcxgLMd8V2Fig=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ElWT6NgebivVlDGLueM3Bq6D1y2Dt7QGFEU/78tGfdYyjwPc2XpN1J2pgr3kLbr3U t3H7mFbUZr5PZdchAzzl82rTCPHDiOe0OkeexvuKthpHI28prApjbBr7kmhQm6Snc6 Fn84DnjMnkIXSy+Xel4W+BIaoVYGQJcVekPkrLvL1zGYyvKoySqCw5gluyRdH+ymT4 6QtbtBFpbq86WweYpDkrAJigUSgBicRDnLi8M8BhDzS7V2OpWo7dyx/VBwG5sQMKBh 4E1EaBJQzr6LWahfjhyEDYSmQ5syRVYmjrWiq1gRVyDIlO9AdRxipWKJLL8NZw6BR8 9+pjmeBbYFuTg== 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 6.1 55/61] pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv Date: Wed, 31 Jul 2024 20:26:13 -0400 Message-ID: <20240801002803.3935985-55-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240801002803.3935985-1-sashal@kernel.org> References: <20240801002803.3935985-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.1.102 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 881d420637bf1..092c9ac0d26d2 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -39,7 +39,6 @@ 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) { @@ -58,7 +57,7 @@ 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