linux-kernel - [PATCH 1/4] iommu/amd: Check SNP support before enabling IOMMU

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: <0b74c3fce90ea464621c0be1dbf681bf46f1aadd.1737505394.git.ashish.kalra@amd.com>
Date: Wed, 22 Jan 2025 01:00:04 +0000
From: Ashish Kalra <Ashish.Kalra@....com>
To: <seanjc@...gle.com>, <pbonzini@...hat.com>, <tglx@...utronix.de>,
	<mingo@...hat.com>, <bp@...en8.de>, <dave.hansen@...ux.intel.com>,
	<x86@...nel.org>, <hpa@...or.com>, <thomas.lendacky@....com>,
	<john.allen@....com>, <herbert@...dor.apana.org.au>, <davem@...emloft.net>,
	<joro@...tes.org>, <suravee.suthikulpanit@....com>, <will@...nel.org>,
	<robin.murphy@....com>
CC: <michael.roth@....com>, <dionnaglaze@...gle.com>, <vasant.hegde@....com>,
	<kvm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	<linux-crypto@...r.kernel.org>, <linux-coco@...ts.linux.dev>,
	<iommu@...ts.linux.dev>
Subject: [PATCH 1/4] iommu/amd: Check SNP support before enabling IOMMU

From: Vasant Hegde <vasant.hegde@....com>

iommu_snp_enable() checks for IOMMU feature support and page table
compatibility. Ideally this check should be done before enabling
IOMMUs. Currently its done after enabling IOMMUs. Also its causes
issue if kvm_amd is builtin.

Hence move SNP enable check before enabling IOMMUs.

Fixes: 04d65a9dbb33 ("iommu/amd: Don't rely on external callers to enable IOMMU SNP support")
Cc: Ashish Kalra <ashish.kalra@....com>
Signed-off-by: Vasant Hegde <vasant.hegde@....com>
---
 drivers/iommu/amd/init.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index c5cd92edada0..419a0bc8eeea 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -3256,13 +3256,14 @@ static int __init state_next(void)
 		}
 		break;
 	case IOMMU_ACPI_FINISHED:
+		/* SNP enable has to be called after early_amd_iommu_init() */
+		iommu_snp_enable();
 		early_enable_iommus();
 		x86_platform.iommu_shutdown = disable_iommus;
 		init_state = IOMMU_ENABLED;
 		break;
 	case IOMMU_ENABLED:
 		register_syscore_ops(&amd_iommu_syscore_ops);
-		iommu_snp_enable();
 		ret = amd_iommu_init_pci();
 		init_state = ret ? IOMMU_INIT_ERROR : IOMMU_PCI_INIT;
 		break;
-- 
2.34.1