linux-kernel - [PATCH v2 06/10] iommu/arm-smmu-v3: Allocate vmid in arm_vsmmu

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: <3f7c5b84c4f8605688ac08fc2ea2dab08a3c5c0c.1769044718.git.nicolinc@nvidia.com>
Date: Wed, 21 Jan 2026 17:24:24 -0800
From: Nicolin Chen <nicolinc@...dia.com>
To: <will@...nel.org>, <robin.murphy@....com>, <jgg@...dia.com>
CC: <joro@...tes.org>, <jpb@...nel.org>, <praan@...gle.com>,
	<miko.lenczewski@....com>, <linux-arm-kernel@...ts.infradead.org>,
	<iommu@...ts.linux.dev>, <linux-kernel@...r.kernel.org>,
	<patches@...ts.linux.dev>
Subject: [PATCH v2 06/10] iommu/arm-smmu-v3: Allocate vmid in arm_vsmmu_init

VMID owned by a vSMMU should be allocated in the viommu_init callback, as
HW like tegra241-cmdqv needs to setup VINTF with the VMID.

Signed-off-by: Nicolin Chen <nicolinc@...dia.com>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h   |  1 +
 .../arm/arm-smmu-v3/arm-smmu-v3-iommufd.c     | 21 +++++++++++++++++--
 .../iommu/arm/arm-smmu-v3/tegra241-cmdqv.c    |  1 +
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 696ebb89ffa3..8aecdbceb974 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -1190,6 +1190,7 @@ size_t arm_smmu_get_viommu_size(struct device *dev,
 int arm_vsmmu_init(struct iommufd_viommu *viommu,
 		   struct iommu_domain *parent_domain,
 		   const struct iommu_user_data *user_data);
+void arm_vsmmu_destroy(struct iommufd_viommu *viommu);
 int arm_smmu_attach_prepare_vmaster(struct arm_smmu_attach_state *state,
 				    struct arm_smmu_nested_domain *nested_domain);
 void arm_smmu_attach_commit_vmaster(struct arm_smmu_attach_state *state);
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
index 34c7bd4cfd84..9998871f69a0 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3-iommufd.c
@@ -404,7 +404,17 @@ int arm_vsmmu_cache_invalidate(struct iommufd_viommu *viommu,
 	return ret;
 }
 
+void arm_vsmmu_destroy(struct iommufd_viommu *viommu)
+{
+	struct arm_vsmmu *vsmmu = container_of(viommu, struct arm_vsmmu, core);
+
+	mutex_lock(&arm_smmu_asid_lock);
+	ida_free(&vsmmu->smmu->vmid_map, vsmmu->vmid);
+	mutex_unlock(&arm_smmu_asid_lock);
+}
+
 static const struct iommufd_viommu_ops arm_vsmmu_ops = {
+	.destroy = arm_vsmmu_destroy,
 	.alloc_domain_nested = arm_vsmmu_alloc_domain_nested,
 	.cache_invalidate = arm_vsmmu_cache_invalidate,
 };
@@ -454,14 +464,21 @@ int arm_vsmmu_init(struct iommufd_viommu *viommu,
 	struct arm_smmu_device *smmu =
 		container_of(viommu->iommu_dev, struct arm_smmu_device, iommu);
 	struct arm_smmu_domain *s2_parent = to_smmu_domain(parent_domain);
+	int id;
 
 	if (s2_parent->smmu != smmu)
 		return -EINVAL;
 
+	mutex_lock(&arm_smmu_asid_lock);
+	id = ida_alloc_range(&smmu->vmid_map, 1, (1 << smmu->vmid_bits) - 1,
+			     GFP_KERNEL);
+	mutex_unlock(&arm_smmu_asid_lock);
+	if (id < 0)
+		return id;
+
+	vsmmu->vmid = id;
 	vsmmu->smmu = smmu;
 	vsmmu->s2_parent = s2_parent;
-	/* FIXME Move VMID allocation from the S2 domain allocation to here */
-	vsmmu->vmid = s2_parent->s2_cfg.vmid;
 
 	if (viommu->type == IOMMU_VIOMMU_TYPE_ARM_SMMUV3) {
 		viommu->ops = &arm_vsmmu_ops;
diff --git a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
index 378104cd395e..67e72115d43a 100644
--- a/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
+++ b/drivers/iommu/arm/arm-smmu-v3/tegra241-cmdqv.c
@@ -1209,6 +1209,7 @@ static void tegra241_cmdqv_destroy_vintf_user(struct iommufd_viommu *viommu)
 		iommufd_viommu_destroy_mmap(&vintf->vsmmu.core,
 					    vintf->mmap_offset);
 	tegra241_cmdqv_remove_vintf(vintf->cmdqv, vintf->idx);
+	arm_vsmmu_destroy(viommu);
 }
 
 static void tegra241_vintf_destroy_vsid(struct iommufd_vdevice *vdev)
-- 
2.43.0