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From: "Brijesh Singh" <brijesh.singh@amd.com>
To: devel@edk2.groups.io
Cc: James Bottomley <jejb@linux.ibm.com>, Min Xu <min.m.xu@intel.com>,
	Jiewen Yao <jiewen.yao@intel.com>,
	Tom Lendacky <thomas.lendacky@amd.com>,
	Jordan Justen <jordan.l.justen@intel.com>,
	Ard Biesheuvel <ardb+tianocore@kernel.org>,
	Erdem Aktas <erdemaktas@google.com>,
	Michael Roth <Michael.Roth@amd.com>,
	Gerd Hoffmann <kraxel@redhat.com>,
	Brijesh Singh <brijesh.singh@amd.com>,
	Michael Roth <michael.roth@amd.com>,
	Jiewen Yao <Jiewen.yao@intel.com>,
	Laszlo Ersek <lersek@redhat.com>
Subject: [PATCH v8 13/32] OvmfPkg/AmdSevDxe: do not use extended PCI config space
Date: Mon, 20 Sep 2021 13:45:45 -0500	[thread overview]
Message-ID: <20210920184604.31590-14-brijesh.singh@amd.com> (raw)
In-Reply-To: <20210920184604.31590-1-brijesh.singh@amd.com>

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=3275

Commit 85b8eac59b8c5bd9c7eb9afdb64357ce1aa2e803 added support to ensure
that MMIO is only performed against the un-encrypted memory. If MMIO
is performed against encrypted memory, a #GP is raised.

The AmdSevDxe uses the functions provided by the MemEncryptSevLib to
clear the memory encryption mask from the page table. If the
MemEncryptSevLib is extended to include VmgExitLib then depedency
chain will look like this:

OvmfPkg/AmdSevDxe/AmdSevDxe.inf
-----> MemEncryptSevLib                    class
-----> "OvmfPkg/BaseMemEncryptSevLib/DxeMemEncryptSevLib.inf"   instance
-----> VmgExitLib                          class
-----> "OvmfPkg/VmgExitLib"    instance
-----> LocalApicLib                        class
-----> "UefiCpuPkg/BaseXApicX2ApicLib/BaseXApicX2ApicLib.inf" instance
-----> TimerLib                            class
-----> "OvmfPkg/AcpiTimerLib/DxeAcpiTimerLib.inf"   instance
-----> PciLib                                           class
-----> "OvmfPkg/DxePciLibI440FxQ35/DxePciLibI440FxQ35.inf"    instance
-----> PciExpressLib                                          class
-----> "MdePkg/BasePciExpressLib/BasePciExpressLib.inf"  instance

The LocalApicLib provides a constructor that gets called before the
AmdSevDxe can clear the memory encryption mask from the MMIO regions.

When running under the Q35 machine type, the call chain looks like this:

AcpiTimerLibConstructor ()  [AcpiTimerLib]
  PciRead32 ()              [DxePciLibI440FxQ35]
   PciExpressRead32 ()      [PciExpressLib]

The PciExpressRead32 () reads the MMIO region. The MMIO regions are not
yet mapped un-encrypted, so the check introduced in the commit
85b8eac59b8c5bd9c7eb9afdb64357ce1aa2e803 raises a #GP.

The AmdSevDxe driver does not require the access to the extended PCI
config space. Accessing a normal PCI config space, via IO port should be
sufficent. Use the module-scope override to make the AmdSevDxe use the
BasePciLib instead of BasePciExpressLib so that PciRead32 () uses the
IO ports instead of the extended config space.

Cc: Michael Roth <michael.roth@amd.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Jiewen Yao <Jiewen.yao@intel.com>
Suggested-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
 OvmfPkg/AmdSev/AmdSevX64.dsc | 5 ++++-
 OvmfPkg/Bhyve/BhyveX64.dsc   | 5 ++++-
 OvmfPkg/OvmfPkgIa32X64.dsc   | 5 ++++-
 OvmfPkg/OvmfPkgX64.dsc       | 5 ++++-
 OvmfPkg/OvmfXen.dsc          | 5 ++++-
 5 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/OvmfPkg/AmdSev/AmdSevX64.dsc b/OvmfPkg/AmdSev/AmdSevX64.dsc
index e6cd10b75922..a8ea08a10a99 100644
--- a/OvmfPkg/AmdSev/AmdSevX64.dsc
+++ b/OvmfPkg/AmdSev/AmdSevX64.dsc
@@ -812,7 +812,10 @@ [Components]
 !endif
 
   OvmfPkg/PlatformDxe/Platform.inf
-  OvmfPkg/AmdSevDxe/AmdSevDxe.inf
+  OvmfPkg/AmdSevDxe/AmdSevDxe.inf {
+    <LibraryClasses>
+    PciLib|MdePkg/Library/BasePciLibCf8/BasePciLibCf8.inf
+  }
   OvmfPkg/IoMmuDxe/IoMmuDxe.inf
 
   #
diff --git a/OvmfPkg/Bhyve/BhyveX64.dsc b/OvmfPkg/Bhyve/BhyveX64.dsc
index d8fe607d1cf7..f45634996247 100644
--- a/OvmfPkg/Bhyve/BhyveX64.dsc
+++ b/OvmfPkg/Bhyve/BhyveX64.dsc
@@ -790,7 +790,10 @@ [Components]
 !endif
 
   OvmfPkg/PlatformDxe/Platform.inf
-  OvmfPkg/AmdSevDxe/AmdSevDxe.inf
+  OvmfPkg/AmdSevDxe/AmdSevDxe.inf {
+    <LibraryClasses>
+    PciLib|MdePkg/Library/BasePciLibCf8/BasePciLibCf8.inf
+  }
   OvmfPkg/IoMmuDxe/IoMmuDxe.inf
 
 
diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc
index a467ab7090fb..f42abc041c0c 100644
--- a/OvmfPkg/OvmfPkgIa32X64.dsc
+++ b/OvmfPkg/OvmfPkgIa32X64.dsc
@@ -965,7 +965,10 @@ [Components.X64]
 !endif
 
   OvmfPkg/PlatformDxe/Platform.inf
-  OvmfPkg/AmdSevDxe/AmdSevDxe.inf
+  OvmfPkg/AmdSevDxe/AmdSevDxe.inf {
+    <LibraryClasses>
+    PciLib|MdePkg/Library/BasePciLibCf8/BasePciLibCf8.inf
+  }
   OvmfPkg/IoMmuDxe/IoMmuDxe.inf
 
 !if $(SMM_REQUIRE) == TRUE
diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc
index e56b83d95e09..19cc5d4122e2 100644
--- a/OvmfPkg/OvmfPkgX64.dsc
+++ b/OvmfPkg/OvmfPkgX64.dsc
@@ -963,7 +963,10 @@ [Components]
 !endif
 
   OvmfPkg/PlatformDxe/Platform.inf
-  OvmfPkg/AmdSevDxe/AmdSevDxe.inf
+  OvmfPkg/AmdSevDxe/AmdSevDxe.inf {
+    <LibraryClasses>
+    PciLib|MdePkg/Library/BasePciLibCf8/BasePciLibCf8.inf
+  }
   OvmfPkg/IoMmuDxe/IoMmuDxe.inf
 
 !if $(SMM_REQUIRE) == TRUE
diff --git a/OvmfPkg/OvmfXen.dsc b/OvmfPkg/OvmfXen.dsc
index a31519e356b7..383cb03d2a14 100644
--- a/OvmfPkg/OvmfXen.dsc
+++ b/OvmfPkg/OvmfXen.dsc
@@ -729,7 +729,10 @@ [Components]
   }
 
   OvmfPkg/PlatformDxe/Platform.inf
-  OvmfPkg/AmdSevDxe/AmdSevDxe.inf
+  OvmfPkg/AmdSevDxe/AmdSevDxe.inf {
+    <LibraryClasses>
+    PciLib|MdePkg/Library/BasePciLibCf8/BasePciLibCf8.inf
+  }
   OvmfPkg/IoMmuDxe/IoMmuDxe.inf
 
   #
-- 
2.25.1


  parent reply	other threads:[~2021-09-20 18:46 UTC|newest]

Thread overview: 40+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-20 18:45 [PATCH v8 00/32] Add AMD Secure Nested Paging (SEV-SNP) support Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 01/32] OvmfPkg/SecMain: move SEV specific routines in AmdSev.c Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 02/32] UefiCpuPkg/MpInitLib: " Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 03/32] OvmfPkg/ResetVector: move clearing GHCB in SecMain Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 04/32] OvmfPkg/ResetVector: introduce metadata descriptor for VMM use Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 05/32] OvmfPkg: reserve SNP secrets page Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 06/32] OvmfPkg: reserve CPUID page Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 07/32] OvmfPkg/ResetVector: pre-validate the data pages used in SEC phase Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 08/32] OvmfPkg/ResetVector: use SEV-SNP-validated CPUID values Brijesh Singh
2021-09-22  7:55   ` Gerd Hoffmann
2021-09-22 23:10     ` Michael Roth
2021-09-23  8:25       ` Gerd Hoffmann
2021-09-20 18:45 ` [PATCH v8 09/32] OvmfPkg/MemEncryptSevLib: add MemEncryptSevSnpEnabled() Brijesh Singh
2021-09-22  8:00   ` Gerd Hoffmann
2021-09-24 10:46     ` Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 10/32] OvmfPkg/SecMain: register GHCB gpa for the SEV-SNP guest Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 11/32] OvmfPkg/VmgExitLib: use SEV-SNP-validated CPUID values Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 12/32] OvmfPkg/PlatformPei: register GHCB gpa for the SEV-SNP guest Brijesh Singh
2021-09-20 18:45 ` Brijesh Singh [this message]
2021-09-20 18:45 ` [PATCH v8 14/32] OvmfPkg/MemEncryptSevLib: add support to validate system RAM Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 15/32] OvmfPkg/MemEncryptSevLib: add function to check the VMPL0 Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 16/32] OvmfPkg/BaseMemEncryptSevLib: skip the pre-validated system RAM Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 17/32] OvmfPkg/MemEncryptSevLib: add support to validate > 4GB memory in PEI phase Brijesh Singh
2021-09-22  8:21   ` Gerd Hoffmann
2021-09-24 10:48     ` Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 18/32] OvmfPkg/SecMain: validate the memory used for decompressing Fv Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 19/32] OvmfPkg/PlatformPei: validate the system RAM when SNP is active Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 20/32] UefiCpuPkg: Define ConfidentialComputingGuestAttr Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 21/32] OvmfPkg/PlatformPei: set PcdConfidentialComputingAttr when SEV is active Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 22/32] UefiCpuPkg/MpInitLib: use PcdConfidentialComputingAttr to check SEV status Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 23/32] UefiCpuPkg: add PcdGhcbHypervisorFeatures Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 24/32] OvmfPkg/PlatformPei: set the Hypervisor Features PCD Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 25/32] MdePkg/GHCB: increase the GHCB protocol max version Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 26/32] UefiCpuPkg/MpLib: add support to register GHCB GPA when SEV-SNP is enabled Brijesh Singh
2021-09-20 18:45 ` [PATCH v8 27/32] UefiCpuPkg/MpInitLib: use BSP to do extended topology check Brijesh Singh
2021-09-20 18:46 ` [PATCH v8 28/32] OvmfPkg/MemEncryptSevLib: change the page state in the RMP table Brijesh Singh
2021-09-20 18:46 ` [PATCH v8 29/32] OvmfPkg/MemEncryptSevLib: skip page state change for Mmio address Brijesh Singh
2021-09-20 18:46 ` [PATCH v8 30/32] OvmfPkg/PlatformPei: mark cpuid and secrets memory reserved in EFI map Brijesh Singh
2021-09-20 18:46 ` [PATCH v8 31/32] OvmfPkg/AmdSev: expose the SNP reserved pages through configuration table Brijesh Singh
2021-09-20 18:46 ` [PATCH v8 32/32] UefiCpuPkg/MpInitLib: Use SEV-SNP AP Creation NAE event to launch APs Brijesh Singh

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