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 675EB1E80BE; Thu, 1 Aug 2024 00:40:13 +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=1722472813; cv=none; b=UCvX7aWcYKa/R9a3fb3msJclBxtGeuOQun+MMlhG7C8cmF7IvInzfBm9kIpWV/A8klC+8hzNliDtmmduDZJbs6W/GCaxlElwADAtFZQLr33YE7HtGucxgdgiODqXxfU6dzysrkoRBD7G5YOrNqZtZFnjBi7upiBAlLA5KnlXYz0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722472813; c=relaxed/simple; bh=hDFH0xuVEwXXPx+0//7xppgQ92FJEKmcmTYJrdk8Hrs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Z9TNWBC+oayreV5jQxat2ABSK5oz39O/BGjbuqPUIQz6Y6Xb82LpIeFtGQJibaN0iOPBnA85So2YsnzO/F3QVGkOpc1Y3Ad8Bgdh1F8ciSYeEde0iB3gVkxT2fvWCFCfwlpnTzjOVGtvVDqA+Y2GOLXUAVXCAIdmZRBYgV58BP8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=RN2K7M3U; 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="RN2K7M3U" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E423C4AF10; Thu, 1 Aug 2024 00:40:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1722472813; bh=hDFH0xuVEwXXPx+0//7xppgQ92FJEKmcmTYJrdk8Hrs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=RN2K7M3U8Qgq2A6iJgKNgsmHLeB1N+zFlYsA8FEzdLlvDBUlu7ru2LpRxrYGVpP/T QdWkRr9ShCvJ/lZKmEXND89rR25qkp/a1LpwKR4zniuBvcLAffm0wWHbjibW+dAkOq JAwhJqabHkT0VyORT/dyjIU1piSPwG7PgqIexc9Gn6UuTWAhJuCTqGyHmnDm/yHiaY uW94kG7z7qp0r8d8ie6bKbYoXVHWFBqlLBTmXixuuFP1jM1d+uDk0zf7VSTKcLMrom USCeL2d4viVeKFXZjgJWhz6rywJ80Cld9laqgyV89HDrU/Hl4A3t4xWcsaowFnvj7w rRsKVofXZsJOg== 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 5.4 18/22] pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv Date: Wed, 31 Jul 2024 20:38:47 -0400 Message-ID: <20240801003918.3939431-18-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240801003918.3939431-1-sashal@kernel.org> References: <20240801003918.3939431-1-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 5.4.281 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 d7b2b47bc33eb..3824942618305 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -35,7 +35,6 @@ 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) { @@ -54,7 +53,7 @@ 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