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 7EE394170BE; Sat, 28 Feb 2026 17:45:20 +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=1772300720; cv=none; b=NdukO/PlpV9YPnDNuP3Lka+AjL+LPdSnbg/rUeE4a3P2ijQ+Li1PnsKPZQFrKUdfIN1Tdcm0zi5Yea5XWcZ0AoGKhd55z5Fs82JvK7iXI4hMs9awoEsSV+RHnjTw79Bq8SYaS5LRhlXSe/7jo43WriMGZrz/vc6NfQqDW/zF3XI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772300720; c=relaxed/simple; bh=VGRqTs+iJEq+2KfvW+RRrTfqytroJsAWwlaHGjT8bjA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=BVszQXcbgCKHjQ6fvOm630lGwDk1dZN58MDdOwqa0J7mmnle+ju4lqaVWiKw4gZ2QbwgQnmgkNOGpEdJVKvzkPPGhFunqqJh+xFdiesuVG4GMPpg56/aOsPoaNzDjShrzXSQvag6MjzoVt/JBsU0iGMeU9eS22LaWckWjmA0tXM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MvLsS99m; 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="MvLsS99m" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B8A4DC19425; Sat, 28 Feb 2026 17:45:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772300720; bh=VGRqTs+iJEq+2KfvW+RRrTfqytroJsAWwlaHGjT8bjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MvLsS99mlhN/KwGbeczkEhcD6Slk3awo9st0k5rGyCtTFFN8iRDKAUw95j8NCRVZL TmtsAeAsuHlyyJ305FUzqOkFcAouN4hbMe3n6fN/wmj9RLbfm+SHjQKHuZH8XkWumh +mxb6vzHTPJ6z+P007p1cvTCkIP/tJpuhwAgVu1hB3LhI2zSzwSLnWcYf4ZUsHsGWp OafnyyB1QbPDLiIHXli76AQqq1q42nl74L2RcLur1TawsZ5pplCGv6qC3Qj3OQUfEy MMhEAJQ1pxV8bum6opov1HalkKh9nWQtdPk1HrveGYQRwYMSFHVni/xj9ijjOXiSa3 LcageaYIPCM+A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Jinhui Guo , Bjorn Helgaas , Dan Williams , Sasha Levin Subject: [PATCH 6.19 756/844] PCI: Fix pci_slot_trylock() error handling Date: Sat, 28 Feb 2026 12:31:09 -0500 Message-ID: <20260228173244.1509663-757-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20260228173244.1509663-1-sashal@kernel.org> References: <20260228173244.1509663-1-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 Content-Transfer-Encoding: 8bit From: Jinhui Guo [ Upstream commit 9368d1ee62829b08aa31836b3ca003803caf0b72 ] Commit a4e772898f8b ("PCI: Add missing bridge lock to pci_bus_lock()") delegates the bridge device's pci_dev_trylock() to pci_bus_trylock() in pci_slot_trylock(), but it forgets to remove the corresponding pci_dev_unlock() when pci_bus_trylock() fails. Before a4e772898f8b, the code did: if (!pci_dev_trylock(dev)) /* <- lock bridge device */ goto unlock; if (dev->subordinate) { if (!pci_bus_trylock(dev->subordinate)) { pci_dev_unlock(dev); /* <- unlock bridge device */ goto unlock; } } After a4e772898f8b the bridge-device lock is no longer taken, but the pci_dev_unlock(dev) on the failure path was left in place, leading to the bug. This yields one of two errors: 1. A warning that the lock is being unlocked when no one holds it. 2. An incorrect unlock of a lock that belongs to another thread. Fix it by removing the now-redundant pci_dev_unlock(dev) on the failure path. [Same patch later posted by Keith at https://patch.msgid.link/20260116184150.3013258-1-kbusch@meta.com] Fixes: a4e772898f8b ("PCI: Add missing bridge lock to pci_bus_lock()") Signed-off-by: Jinhui Guo Signed-off-by: Bjorn Helgaas Reviewed-by: Dan Williams Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20251212145528.2555-1-guojinhui.liam@bytedance.com Signed-off-by: Sasha Levin --- drivers/pci/pci.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index a4eb3bc2127ae..8500b862f4f2e 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5355,10 +5355,8 @@ static int pci_slot_trylock(struct pci_slot *slot) if (!dev->slot || dev->slot != slot) continue; if (dev->subordinate) { - if (!pci_bus_trylock(dev->subordinate)) { - pci_dev_unlock(dev); + if (!pci_bus_trylock(dev->subordinate)) goto unlock; - } } else if (!pci_dev_trylock(dev)) goto unlock; } -- 2.51.0