linux-kernel - [RFC PATCH v2 26/32] iommu/vt-d: reclaim domain ids of the preserved devices

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251202230303.1017519-27-skhawaja@google.com>
Date: Tue,  2 Dec 2025 23:02:56 +0000
From: Samiullah Khawaja <skhawaja@...gle.com>
To: David Woodhouse <dwmw2@...radead.org>, Lu Baolu <baolu.lu@...ux.intel.com>, 
	Joerg Roedel <joro@...tes.org>, Will Deacon <will@...nel.org>, 
	Pasha Tatashin <pasha.tatashin@...een.com>, Jason Gunthorpe <jgg@...pe.ca>, iommu@...ts.linux.dev
Cc: Samiullah Khawaja <skhawaja@...gle.com>, Robin Murphy <robin.murphy@....com>, 
	Pratyush Yadav <pratyush@...nel.org>, Kevin Tian <kevin.tian@...el.com>, 
	Alex Williamson <alex@...zbot.org>, linux-kernel@...r.kernel.org, 
	Saeed Mahameed <saeedm@...dia.com>, Adithya Jayachandran <ajayachandra@...dia.com>, 
	Parav Pandit <parav@...dia.com>, Leon Romanovsky <leonro@...dia.com>, William Tu <witu@...dia.com>, 
	Vipin Sharma <vipinsh@...gle.com>, dmatlack@...gle.com, YiFei Zhu <zhuyifei@...gle.com>, 
	Chris Li <chrisl@...nel.org>, praan@...gle.com
Subject: [RFC PATCH v2 26/32] iommu/vt-d: reclaim domain ids of the preserved devices

During IOMMU unit state restore, reclaim the domain ids of the preserved
devices so these are not acquired by another device.

Signed-off-by: Samiullah Khawaja <skhawaja@...gle.com>
---
 drivers/iommu/intel/liveupdate.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/iommu/intel/liveupdate.c b/drivers/iommu/intel/liveupdate.c
index 140887187084..fc1e8545ed0e 100644
--- a/drivers/iommu/intel/liveupdate.c
+++ b/drivers/iommu/intel/liveupdate.c
@@ -92,6 +92,15 @@ static void restore_iommu_context(struct intel_iommu *iommu)
 	}
 }
 
+static int __restore_used_domain_ids(struct device_ser *ser, void *arg)
+{
+	int id = ser->domain_iommu_ser.did;
+	struct intel_iommu *iommu = arg;
+
+	ida_alloc_range(&iommu->domain_ida, id, id, GFP_KERNEL);
+	return 0;
+}
+
 void intel_iommu_liveupdate_restore_root_table(struct intel_iommu *iommu,
 					       struct iommu_ser *iommu_ser)
 {
@@ -99,6 +108,7 @@ void intel_iommu_liveupdate_restore_root_table(struct intel_iommu *iommu,
 	iommu->root_entry = __va(iommu_ser->intel.root_table);
 
 	restore_iommu_context(iommu);
+	iommu_for_each_preserved_device(__restore_used_domain_ids, iommu);
 	pr_info("Restored IOMMU[0x%llx] Root Table at: 0x%llx\n",
 		iommu->reg_phys, iommu_ser->intel.root_table);
 }
-- 
2.52.0.158.g65b55ccf14-goog