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 31E771CD2C; Sun, 1 Mar 2026 01:36:44 +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=1772329005; cv=none; b=Yp6egdlWBDdHCScAU1PzjiJHfWUjtTD8ajbHOEgSeg4/vJtkwlw8PPoEyuWC+g1ltmtLu/n8XTL+0+LgcyKjJr111QqYCmRylYHvfPWy3G+4UYI4JLaqZwWnldNJm//6OUPMXFPpFzqpPzCm2Ncg3IxJnc3ziUzC9Y0txjCuk7A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772329005; c=relaxed/simple; bh=4+s8UOxyl3+9j0sEeu1gBMLiqag+x8ZiDV9+Cvh8OtA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Uv8nr06d4tqCPO/W6roSBjQuAfUs9rO68nyFSbAd+64mwRaG41F6wqLbn0IJizkgqnVO3eFQRPqL1EeY7W7g+d846gBysIHLkU+ARJ1H31fKmIXk5rCfzlXOJhqDowH5yb8Q59/UUYGpzVaeULbvFkZGfbLbP1k/at8rI2BTP+g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eQKHrdPJ; 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="eQKHrdPJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36AABC19421; Sun, 1 Mar 2026 01:36:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772329004; bh=4+s8UOxyl3+9j0sEeu1gBMLiqag+x8ZiDV9+Cvh8OtA=; h=From:To:Cc:Subject:Date:From; b=eQKHrdPJet7D23XX21PLwY6o566JMeSzuGhx6irM9FAzibozrP1EPCMwD+1m0a/hG ZMKibPpAyipOV5D/Rh8tmQtfc798LYGGgZDDsAy4X20c3iXAnPKHbqshKoQx9DSKzf kUxtVp2QkMyb1RtSPeoHTtRmurXUO3o/9KhAAN2UKPTJKBGVj04V5QrGrBANUmbsM9 092TNRTCvpIE3YTt+Xv4a+veLKIDfvSpAYLmnn8RNH6lzpSJSmkbjtwjLcPl6lqHZt MvELjkjErPlGjfRFPWfCBrw1Ku97uF/hwh32XDFrJZT8R6Y+bdN9TfeVvCbuD0rLhx pm9MsWx+ZcryQ== From: Sasha Levin To: stable@vger.kernel.org, guojinhui.liam@bytedance.com Cc: Bjorn Helgaas , Dan Williams , linux-pci@vger.kernel.org Subject: FAILED: Patch "PCI: Fix pci_slot_trylock() error handling" failed to apply to 6.6-stable tree Date: Sat, 28 Feb 2026 20:36:42 -0500 Message-ID: <20260301013643.1696741-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Hint: ignore X-stable: review Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.6-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 9368d1ee62829b08aa31836b3ca003803caf0b72 Mon Sep 17 00:00:00 2001 From: Jinhui Guo Date: Fri, 12 Dec 2025 22:55:28 +0800 Subject: [PATCH] PCI: Fix pci_slot_trylock() error handling 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 --- 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 13dbb405dc31f..59319e08fca61 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5346,10 +5346,8 @@ 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