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 CE01A2DCBFA; Sun, 1 Mar 2026 01:34:03 +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=1772328843; cv=none; b=bQKOPUS2xx6aTNXAxhfPcX5lpSOpbbKzQf79/lma5o/F0kZTYFCW4JX0PO2xgdiGWoO7bNcgDdczKzzAaM0JuqrWvqhwgpbpGXgwYGcIAK6H2RuummGfNiSaUvhNrfIQ03fc6h0fShlp20DPAlmU5EW/NUbOcCtZpbMJHYEke+s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772328843; c=relaxed/simple; bh=0Q276LfkLkXsD1NaLQlf+Wme6Karbo2sw89fG6cvPwA=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=ptKabo5P5EZDuyyIBPQg/bWK+K65oBceTqVq+NZgFuu1iMy+OTkXXFJ5h/cxU9z8MGDfsVbmaTo++aoblBBgVoDaI4Y7lMzLUOddjkU7eryWTiVm9+R0fmCMLWz0MZIIBDZHedX/jU2SmDSsRguQxYyARXw6M6JSdpSVworigGk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=b0iF91X1; 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="b0iF91X1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 20A84C19421; Sun, 1 Mar 2026 01:34:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772328843; bh=0Q276LfkLkXsD1NaLQlf+Wme6Karbo2sw89fG6cvPwA=; h=From:To:Cc:Subject:Date:From; b=b0iF91X1vLA6kAbjGd6cMgdTZ27YmEv4NYrXcriFDBplTY6LXZ+zvXaRG+HHHSYuF j8u03oIx7e61TSc32rABcxDKb65p2AnhL3thdG+bx//XKdxzK5z3EEBLmtAbkVIo8m MEev4T3EyPuG0uEnmYzjFpA0T94hPliIFN25iSjctGUTS8ogDHB4mNfnnlQc7vilea AGnxA5/5F06TvVLPNfaNiL2Qy1OZcSIDqJemMhLkkm5ijlusiNUvwob0FYCqWUsBMQ vZnSz8HFoC105MHRSHC8t8za9+3WqJOiDgeY9fC7oIKWYi2TTscIuHq9q5HSxuIDqJ rgON0Ash0x+xQ== From: Sasha Levin To: stable@vger.kernel.org, guojinhui.liam@bytedance.com Cc: Lu Baolu , Joerg Roedel , iommu@lists.linux.dev Subject: FAILED: Patch "iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode" failed to apply to 6.6-stable tree Date: Sat, 28 Feb 2026 20:34:01 -0500 Message-ID: <20260301013401.1693386-1-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-Type: text/plain; charset=UTF-8 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 10e60d87813989e20eac1f3eda30b3bae461e7f9 Mon Sep 17 00:00:00 2001 From: Jinhui Guo Date: Thu, 22 Jan 2026 09:48:51 +0800 Subject: [PATCH] iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected") relies on pci_dev_is_disconnected() to skip ATS invalidation for safely-removed devices, but it does not cover link-down caused by faults, which can still hard-lock the system. For example, if a VM fails to connect to the PCIe device, "virsh destroy" is executed to release resources and isolate the fault, but a hard-lockup occurs while releasing the group fd. Call Trace: qi_submit_sync qi_flush_dev_iotlb intel_pasid_tear_down_entry device_block_translation blocking_domain_attach_dev __iommu_attach_device __iommu_device_set_domain __iommu_group_set_domain_internal iommu_detach_group vfio_iommu_type1_detach_group vfio_group_detach_container vfio_group_fops_release __fput Although pci_device_is_present() is slower than pci_dev_is_disconnected(), it still takes only ~70 µs on a ConnectX-5 (8 GT/s, x2) and becomes even faster as PCIe speed and width increase. Besides, devtlb_invalidation_with_pasid() is called only in the paths below, which are far less frequent than memory map/unmap. 1. mm-struct release 2. {attach,release}_dev 3. set/remove PASID 4. dirty-tracking setup The gain in system stability far outweighs the negligible cost of using pci_device_is_present() instead of pci_dev_is_disconnected() to decide when to skip ATS invalidation, especially under GDR high-load conditions. Fixes: 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected") Cc: stable@vger.kernel.org Signed-off-by: Jinhui Guo Link: https://lore.kernel.org/r/20251211035946.2071-3-guojinhui.liam@bytedance.com Signed-off-by: Lu Baolu Signed-off-by: Joerg Roedel --- drivers/iommu/intel/pasid.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index 3f6d78180d799..99692f88b8834 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -218,7 +218,7 @@ devtlb_invalidation_with_pasid(struct intel_iommu *iommu, if (!info || !info->ats_enabled) return; - if (pci_dev_is_disconnected(to_pci_dev(dev))) + if (!pci_device_is_present(to_pci_dev(dev))) return; sid = PCI_DEVID(info->bus, info->devfn); -- 2.51.0