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 EDDACC8EB; Wed, 23 Apr 2025 15:04:13 +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=1745420654; cv=none; b=UqMknopLZOQmQkCO4bEbSYOW1wGaK7vPII2VgMR5ZPwN+GZZ6T8QJ8aYIxnRDR22hoK70S7RNx4gRDgf6LAi1IxC2nD32PVNx05IIKB2Iu8KICemfx6bPrWBvtAOXCe/JZkguAdGqWkwmGJPYX06I1HME/kLH/HK3e+Bh1ggwNY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745420654; c=relaxed/simple; bh=IKoYqb4RnSm/Y/bi5SEKlf0Xr6FkVsXHtsby7QPP3m8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aSNNZHO4PSNSe/BJRp12hgZ8XEFcgWj/craB2DTrsoZ1VYnarUYDrVRy3hn9TtPHsdi1L/zadKSvqrETXAryjpUcu+BPkQcWz5YVtohZBKzIMlip+vEFGUvKuEB6yh5jIkX2qj8cMMoQzGaIl4Ew5KfDVzBbQGsysji4nKd1d/U= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ENEeqoBj; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="ENEeqoBj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E89B6C4CEE2; Wed, 23 Apr 2025 15:04:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745420653; bh=IKoYqb4RnSm/Y/bi5SEKlf0Xr6FkVsXHtsby7QPP3m8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ENEeqoBjLXRPvJrMVY4N3ai/yxJSj1KjCkQZU85kURM0Ti7HqExtrLSi1hMNnPzov eR0fZJ2zq6Zq+QxWVajPIZSfrCwe5Jlx54VCPBn09dKbOubuAub8Ydcrw93Os8G/tp KDJs0Jx1kcmr4ZYZpIgsP0YCYQOx76wohWD/6JXU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ryo Takakura , "Luis Claudio R. Goncalves" , Sebastian Andrzej Siewior , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Bjorn Helgaas , Sasha Levin Subject: [PATCH 6.1 068/291] PCI: vmd: Make vmd_dev::cfg_lock a raw_spinlock_t type Date: Wed, 23 Apr 2025 16:40:57 +0200 Message-ID: <20250423142627.151646345@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250423142624.409452181@linuxfoundation.org> References: <20250423142624.409452181@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ryo Takakura [ Upstream commit 18056a48669a040bef491e63b25896561ee14d90 ] The access to the PCI config space via pci_ops::read and pci_ops::write is a low-level hardware access. The functions can be accessed with disabled interrupts even on PREEMPT_RT. The pci_lock is a raw_spinlock_t for this purpose. A spinlock_t becomes a sleeping lock on PREEMPT_RT, so it cannot be acquired with disabled interrupts. The vmd_dev::cfg_lock is accessed in the same context as the pci_lock. Make vmd_dev::cfg_lock a raw_spinlock_t type so it can be used with interrupts disabled. This was reported as: BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:48 Call Trace: rt_spin_lock+0x4e/0x130 vmd_pci_read+0x8d/0x100 [vmd] pci_user_read_config_byte+0x6f/0xe0 pci_read_config+0xfe/0x290 sysfs_kf_bin_read+0x68/0x90 Signed-off-by: Ryo Takakura Tested-by: Luis Claudio R. Goncalves Acked-by: Luis Claudio R. Goncalves [bigeasy: reword commit message] Signed-off-by: Sebastian Andrzej Siewior Tested-off-by: Luis Claudio R. Goncalves Link: https://lore.kernel.org/r/20250218080830.ufw3IgyX@linutronix.de [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński [bhelgaas: add back report info from https://lore.kernel.org/lkml/20241218115951.83062-1-ryotkkr98@gmail.com/] Signed-off-by: Bjorn Helgaas Signed-off-by: Sasha Levin --- drivers/pci/controller/vmd.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c index a1dd614bdc324..09995b6e73bcc 100644 --- a/drivers/pci/controller/vmd.c +++ b/drivers/pci/controller/vmd.c @@ -110,7 +110,7 @@ struct vmd_irq_list { struct vmd_dev { struct pci_dev *dev; - spinlock_t cfg_lock; + raw_spinlock_t cfg_lock; void __iomem *cfgbar; int msix_count; @@ -387,7 +387,7 @@ static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg, if (!addr) return -EFAULT; - spin_lock_irqsave(&vmd->cfg_lock, flags); + raw_spin_lock_irqsave(&vmd->cfg_lock, flags); switch (len) { case 1: *value = readb(addr); @@ -402,7 +402,7 @@ static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg, ret = -EINVAL; break; } - spin_unlock_irqrestore(&vmd->cfg_lock, flags); + raw_spin_unlock_irqrestore(&vmd->cfg_lock, flags); return ret; } @@ -422,7 +422,7 @@ static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg, if (!addr) return -EFAULT; - spin_lock_irqsave(&vmd->cfg_lock, flags); + raw_spin_lock_irqsave(&vmd->cfg_lock, flags); switch (len) { case 1: writeb(value, addr); @@ -440,7 +440,7 @@ static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg, ret = -EINVAL; break; } - spin_unlock_irqrestore(&vmd->cfg_lock, flags); + raw_spin_unlock_irqrestore(&vmd->cfg_lock, flags); return ret; } @@ -958,7 +958,7 @@ static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id) if (features & VMD_FEAT_OFFSET_FIRST_VECTOR) vmd->first_vec = 1; - spin_lock_init(&vmd->cfg_lock); + raw_spin_lock_init(&vmd->cfg_lock); pci_set_drvdata(dev, vmd); err = vmd_enable_domain(vmd, features); if (err) -- 2.39.5