linux-kernel - [PATCH v2 05/11] iommufd/hw_pagetable: Do not populate user-managed hw

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: <20230511143844.22693-6-yi.l.liu@intel.com>
Date:   Thu, 11 May 2023 07:38:38 -0700
From:   Yi Liu <yi.l.liu@...el.com>
To:     joro@...tes.org, alex.williamson@...hat.com, jgg@...dia.com,
        kevin.tian@...el.com, robin.murphy@....com,
        baolu.lu@...ux.intel.com
Cc:     cohuck@...hat.com, eric.auger@...hat.com, nicolinc@...dia.com,
        kvm@...r.kernel.org, mjrosato@...ux.ibm.com,
        chao.p.peng@...ux.intel.com, yi.l.liu@...el.com,
        yi.y.sun@...ux.intel.com, peterx@...hat.com, jasowang@...hat.com,
        shameerali.kolothum.thodi@...wei.com, lulu@...hat.com,
        suravee.suthikulpanit@....com, iommu@...ts.linux.dev,
        linux-kernel@...r.kernel.org, linux-kselftest@...r.kernel.org,
        zhenzhong.duan@...el.com
Subject: [PATCH v2 05/11] iommufd/hw_pagetable: Do not populate user-managed hw_pagetables

From: Nicolin Chen <nicolinc@...dia.com>

A user-managed hw_pagetable does not need to get populated, since it is
managed by a guest OS. Move the iopt_table_add_domain and list_add_tail
calls into a helper, where the hwpt pointer will be redirected to its
hwpt->parent if it's available.

Signed-off-by: Nicolin Chen <nicolinc@...dia.com>
Signed-off-by: Yi Liu <yi.l.liu@...el.com>
---
 drivers/iommu/iommufd/hw_pagetable.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index ec9b140939ce..73d7d9d07726 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -58,6 +58,24 @@ int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt)
 	return 0;
 }
 
+static int iommufd_hw_pagetable_link_ioas(struct iommufd_hw_pagetable *hwpt)
+{
+	int rc;
+
+	/*
+	 * Only a parent hwpt needs to be linked to the IOAS. And a hwpt->parent
+	 * must be linked to the IOAS already, when it's being allocated.
+	 */
+	if (hwpt->parent)
+		return 0;
+
+	rc = iopt_table_add_domain(&hwpt->ioas->iopt, hwpt->domain);
+	if (rc)
+		return rc;
+	list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list);
+	return 0;
+}
+
 /**
  * iommufd_hw_pagetable_alloc() - Get an iommu_domain for a device
  * @ictx: iommufd context
@@ -151,10 +169,9 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
 			goto out_abort;
 	}
 
-	rc = iopt_table_add_domain(&hwpt->ioas->iopt, hwpt->domain);
+	rc = iommufd_hw_pagetable_link_ioas(hwpt);
 	if (rc)
 		goto out_detach;
-	list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list);
 	return hwpt;
 
 out_detach:
-- 
2.34.1