From: Brijesh Singh <brijesh.singh@amd.com>
To: <x86@kernel.org>, <linux-kernel@vger.kernel.org>,
<kvm@vger.kernel.org>, <linux-efi@vger.kernel.org>,
<platform-driver-x86@vger.kernel.org>,
<linux-coco@lists.linux.dev>, <linux-mm@kvack.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Joerg Roedel <jroedel@suse.de>,
Tom Lendacky <thomas.lendacky@amd.com>,
"H. Peter Anvin" <hpa@zytor.com>,
Ard Biesheuvel <ardb@kernel.org>,
Paolo Bonzini <pbonzini@redhat.com>,
Sean Christopherson <seanjc@google.com>,
"Vitaly Kuznetsov" <vkuznets@redhat.com>,
Jim Mattson <jmattson@google.com>,
"Andy Lutomirski" <luto@kernel.org>,
Dave Hansen <dave.hansen@linux.intel.com>,
Sergio Lopez <slp@redhat.com>, Peter Gonda <pgonda@google.com>,
"Peter Zijlstra" <peterz@infradead.org>,
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
David Rientjes <rientjes@google.com>,
Dov Murik <dovmurik@linux.ibm.com>,
Tobin Feldman-Fitzthum <tobin@ibm.com>,
Borislav Petkov <bp@alien8.de>,
Michael Roth <michael.roth@amd.com>,
Vlastimil Babka <vbabka@suse.cz>,
"Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>,
Andi Kleen <ak@linux.intel.com>,
"Dr . David Alan Gilbert" <dgilbert@redhat.com>,
<brijesh.ksingh@gmail.com>, <tony.luck@intel.com>,
<marcorr@google.com>,
<sathyanarayanan.kuppuswamy@linux.intel.com>,
Brijesh Singh <brijesh.singh@amd.com>
Subject: [PATCH v12 24/46] x86/compressed/acpi: Move EFI detection to helper
Date: Mon, 7 Mar 2022 15:33:34 -0600 [thread overview]
Message-ID: <20220307213356.2797205-25-brijesh.singh@amd.com> (raw)
In-Reply-To: <20220307213356.2797205-1-brijesh.singh@amd.com>
From: Michael Roth <michael.roth@amd.com>
Future patches for SEV-SNP-validated CPUID will also require early
parsing of the EFI configuration. Incrementally move the related
code into a set of helpers that can be re-used for that purpose.
Signed-off-by: Michael Roth <michael.roth@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
---
arch/x86/boot/compressed/Makefile | 1 +
arch/x86/boot/compressed/acpi.c | 28 +++++++----------
arch/x86/boot/compressed/efi.c | 50 +++++++++++++++++++++++++++++++
arch/x86/boot/compressed/misc.h | 16 ++++++++++
4 files changed, 77 insertions(+), 18 deletions(-)
create mode 100644 arch/x86/boot/compressed/efi.c
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 6115274fe10f..e69c3d2e0628 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -103,6 +103,7 @@ endif
vmlinux-objs-$(CONFIG_ACPI) += $(obj)/acpi.o
vmlinux-objs-$(CONFIG_EFI_MIXED) += $(obj)/efi_thunk_$(BITS).o
+vmlinux-objs-$(CONFIG_EFI) += $(obj)/efi.o
efi-obj-$(CONFIG_EFI_STUB) = $(objtree)/drivers/firmware/efi/libstub/lib.a
$(obj)/vmlinux: $(vmlinux-objs-y) $(efi-obj-y) FORCE
diff --git a/arch/x86/boot/compressed/acpi.c b/arch/x86/boot/compressed/acpi.c
index 8bcbcee54aa1..db6c561920f0 100644
--- a/arch/x86/boot/compressed/acpi.c
+++ b/arch/x86/boot/compressed/acpi.c
@@ -87,7 +87,7 @@ static acpi_physical_address kexec_get_rsdp_addr(void)
efi_system_table_64_t *systab;
struct efi_setup_data *esd;
struct efi_info *ei;
- char *sig;
+ enum efi_type et;
esd = (struct efi_setup_data *)get_kexec_setup_data_addr();
if (!esd)
@@ -98,10 +98,9 @@ static acpi_physical_address kexec_get_rsdp_addr(void)
return 0;
}
- ei = &boot_params->efi_info;
- sig = (char *)&ei->efi_loader_signature;
- if (strncmp(sig, EFI64_LOADER_SIGNATURE, 4)) {
- debug_putstr("Wrong kexec EFI loader signature.\n");
+ et = efi_get_type(boot_params);
+ if (et != EFI_TYPE_64) {
+ debug_putstr("Unexpected kexec EFI environment (expected 64-bit EFI).\n");
return 0;
}
@@ -122,29 +121,22 @@ static acpi_physical_address efi_get_rsdp_addr(void)
unsigned long systab, config_tables;
unsigned int nr_tables;
struct efi_info *ei;
+ enum efi_type et;
bool efi_64;
- char *sig;
-
- ei = &boot_params->efi_info;
- sig = (char *)&ei->efi_loader_signature;
- if (!strncmp(sig, EFI64_LOADER_SIGNATURE, 4)) {
+ et = efi_get_type(boot_params);
+ if (et == EFI_TYPE_64)
efi_64 = true;
- } else if (!strncmp(sig, EFI32_LOADER_SIGNATURE, 4)) {
+ else if (et == EFI_TYPE_32)
efi_64 = false;
- } else {
- debug_putstr("Wrong EFI loader signature.\n");
+ else
return 0;
- }
/* Get systab from boot params. */
+ ei = &boot_params->efi_info;
#ifdef CONFIG_X86_64
systab = ei->efi_systab | ((__u64)ei->efi_systab_hi << 32);
#else
- if (ei->efi_systab_hi || ei->efi_memmap_hi) {
- debug_putstr("Error getting RSDP address: EFI system table located above 4GB.\n");
- return 0;
- }
systab = ei->efi_systab;
#endif
if (!systab)
diff --git a/arch/x86/boot/compressed/efi.c b/arch/x86/boot/compressed/efi.c
new file mode 100644
index 000000000000..bad0ce3e2ef6
--- /dev/null
+++ b/arch/x86/boot/compressed/efi.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Helpers for early access to EFI configuration table.
+ *
+ * Originally derived from arch/x86/boot/compressed/acpi.c
+ */
+
+#include "misc.h"
+#include <linux/efi.h>
+#include <asm/efi.h>
+
+/**
+ * efi_get_type - Given a pointer to boot_params, determine the type of EFI environment.
+ *
+ * @bp: pointer to boot_params
+ *
+ * Return: EFI_TYPE_{32,64} for valid EFI environments, EFI_TYPE_NONE otherwise.
+ */
+enum efi_type efi_get_type(struct boot_params *bp)
+{
+ struct efi_info *ei;
+ enum efi_type et;
+ const char *sig;
+
+ ei = &bp->efi_info;
+ sig = (char *)&ei->efi_loader_signature;
+
+ if (!strncmp(sig, EFI64_LOADER_SIGNATURE, 4)) {
+ et = EFI_TYPE_64;
+ } else if (!strncmp(sig, EFI32_LOADER_SIGNATURE, 4)) {
+ et = EFI_TYPE_32;
+ } else {
+ debug_putstr("No EFI environment detected.\n");
+ et = EFI_TYPE_NONE;
+ }
+
+#ifndef CONFIG_X86_64
+ /*
+ * Existing callers like acpi.c treat this case as an indicator to
+ * fall-through to non-EFI, rather than an error, so maintain that
+ * functionality here as well.
+ */
+ if (ei->efi_systab_hi || ei->efi_memmap_hi) {
+ debug_putstr("EFI system table is located above 4GB and cannot be accessed.\n");
+ et = EFI_TYPE_NONE;
+ }
+#endif
+
+ return et;
+}
diff --git a/arch/x86/boot/compressed/misc.h b/arch/x86/boot/compressed/misc.h
index 01cc13c12059..fede1afa39e9 100644
--- a/arch/x86/boot/compressed/misc.h
+++ b/arch/x86/boot/compressed/misc.h
@@ -176,4 +176,20 @@ void boot_stage2_vc(void);
unsigned long sev_verify_cbit(unsigned long cr3);
+enum efi_type {
+ EFI_TYPE_64,
+ EFI_TYPE_32,
+ EFI_TYPE_NONE,
+};
+
+#ifdef CONFIG_EFI
+/* helpers for early EFI config table access */
+enum efi_type efi_get_type(struct boot_params *bp);
+#else
+static inline enum efi_type efi_get_type(struct boot_params *bp)
+{
+ return EFI_TYPE_NONE;
+}
+#endif /* CONFIG_EFI */
+
#endif /* BOOT_COMPRESSED_MISC_H */
--
2.25.1
next prev parent reply other threads:[~2022-03-07 21:36 UTC|newest]
Thread overview: 129+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-07 21:33 [PATCH v12 00/46] Add AMD Secure Nested Paging (SEV-SNP) Guest Support Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 01/46] KVM: SVM: Define sev_features and vmpl field in the VMSA Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] KVM: SVM: Define sev_features and VMPL " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 02/46] KVM: SVM: Create a separate mapping for the SEV-ES save area Brijesh Singh
2022-04-05 18:27 ` [PATCH v12 2.1/46] " Brijesh Singh
2022-04-05 18:55 ` Borislav Petkov
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Tom Lendacky
2022-03-07 21:33 ` [PATCH v12 03/46] KVM: SVM: Create a separate mapping for the GHCB " Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Tom Lendacky
2022-03-07 21:33 ` [PATCH v12 04/46] KVM: SVM: Update the SEV-ES save area mapping Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Tom Lendacky
2022-03-07 21:33 ` [PATCH v12 05/46] x86/boot: Introduce helpers for MSR reads/writes Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 06/46] x86/boot: Use MSR read/write helpers instead of inline assembly Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 07/46] x86/compressed/64: Detect/setup SEV/SME features earlier in boot Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] x86/compressed/64: Detect/setup SEV/SME features earlier during boot tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 08/46] x86/sev: Detect/setup SEV/SME features earlier in boot Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 09/46] x86/mm: Extend cc_attr to include AMD SEV-SNP Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 10/46] x86/sev: Define the Linux specific guest termination reasons Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] x86/sev: Define the Linux-specific " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 11/46] x86/sev: Save the negotiated GHCB version Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 12/46] x86/sev: Check SEV-SNP features support Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 13/46] x86/sev: Add a helper for the PVALIDATE instruction Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 14/46] x86/sev: Check the vmpl level Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] x86/sev: Check the VMPL level tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 15/46] x86/compressed: Add helper for validating pages in the decompression stage Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 16/46] x86/compressed: Register GHCB memory when SEV-SNP is active Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 17/46] x86/sev: " Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 18/46] x86/sev: Add helper for validating pages in early enc attribute changes Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 19/46] x86/kernel: Make the .bss..decrypted section shared in RMP table Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] x86/kernel: Mark the .bss..decrypted section as shared in the " tip-bot2 for Brijesh Singh
2022-06-14 0:46 ` [PATCH v12 19/46] x86/kernel: Make the .bss..decrypted section shared in " Sean Christopherson
2022-06-14 15:43 ` Sean Christopherson
2022-06-14 16:01 ` Tom Lendacky
2022-06-14 16:13 ` Sean Christopherson
2022-06-14 19:00 ` Tom Lendacky
2022-06-14 19:52 ` Sean Christopherson
2022-06-16 16:17 ` Tom Lendacky
2022-06-16 16:41 ` Sean Christopherson
2022-07-01 16:51 ` Borislav Petkov
2022-07-07 20:43 ` Sean Christopherson
2022-03-07 21:33 ` [PATCH v12 20/46] x86/kernel: Validate ROM memory before accessing when SEV-SNP is active Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 21/46] x86/mm: Validate memory when changing the C-bit Brijesh Singh
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 22/46] x86/sev: Use SEV-SNP AP creation to start secondary CPUs Brijesh Singh
2022-04-05 0:24 ` Sean Christopherson
2022-04-05 16:20 ` Brijesh Singh
2022-04-05 19:41 ` Sean Christopherson
2022-04-08 9:09 ` [tip: x86/sev] " tip-bot2 for Tom Lendacky
2022-03-07 21:33 ` [PATCH v12 23/46] x86/head/64: Re-enable stack protection Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` Brijesh Singh [this message]
2022-04-08 9:08 ` [tip: x86/sev] x86/compressed/acpi: Move EFI detection to helper tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 25/46] x86/compressed/acpi: Move EFI system table lookup " Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 26/46] x86/compressed/acpi: Move EFI config " Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 27/46] x86/compressed/acpi: Move EFI vendor " Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 28/46] x86/compressed/acpi: Move EFI kexec handling into common code Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 29/46] x86/boot: Add Confidential Computing type to setup_data Brijesh Singh
2022-04-06 21:19 ` Thomas Gleixner
2022-04-07 14:47 ` Borislav Petkov
2022-04-07 14:57 ` Brijesh Singh
2022-07-17 5:08 ` H. Peter Anvin
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 30/46] KVM: x86: Move lookup of indexed CPUID leafs to helper Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 31/46] x86/sev: Move MSR-based VMGEXITs for CPUID " Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 32/46] x86/compressed/64: Add support for SEV-SNP CPUID table in #VC handlers Brijesh Singh
2022-03-10 14:51 ` Peter Gonda
2022-03-10 21:25 ` Michael Roth
2022-03-11 17:06 ` Joerg Roedel
2022-03-14 17:34 ` Peter Gonda
2022-03-17 13:11 ` Boris Petkov
2022-03-17 20:20 ` Peter Gonda
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 33/46] x86/boot: Add a pointer to Confidential Computing blob in bootparams Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 34/46] x86/compressed: Add SEV-SNP feature detection/setup Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 35/46] x86/compressed: Use firmware-validated CPUID leaves for SEV-SNP guests Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 36/46] x86/compressed: Export and rename add_identity_map() Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 37/46] x86/compressed/64: Add identity mapping for Confidential Computing blob Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 38/46] x86/sev: Add SEV-SNP feature detection/setup Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 39/46] x86/sev: Use firmware-validated CPUID for SEV-SNP guests Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 40/46] x86/sev: add sev=debug cmdline option to dump SNP CPUID table Brijesh Singh
2022-03-25 9:24 ` Borislav Petkov
2022-04-08 9:08 ` [tip: x86/sev] x86/sev: Add a sev= cmdline option tip-bot2 for Michael Roth
2022-03-07 21:33 ` [PATCH v12 41/46] x86/sev: Provide support for SNP guest request NAEs Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 42/46] x86/sev: Register SEV-SNP guest request platform device Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 43/46] virt: Add SEV-SNP guest driver Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-04-18 16:42 ` Dionna Amalie Glaze
2022-04-18 17:14 ` Borislav Petkov
2022-04-18 17:40 ` Tom Lendacky
2022-04-18 21:18 ` Borislav Petkov
2022-08-24 18:01 ` [PATCH v12 43/46] " Dionna Amalie Glaze
2022-08-24 19:28 ` Peter Gonda
2022-08-25 18:54 ` Tom Lendacky
2022-08-25 20:09 ` Peter Gonda
2022-03-07 21:33 ` [PATCH v12 44/46] virt: sevguest: Add support to derive key Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 45/46] virt: sevguest: Add support to get extended report Brijesh Singh
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Brijesh Singh
2022-03-07 21:33 ` [PATCH v12 46/46] virt: sevguest: Add documentation for SEV-SNP CPUID Enforcement Brijesh Singh
2022-03-14 15:37 ` Peter Gonda
2022-04-08 9:08 ` [tip: x86/sev] " tip-bot2 for Michael Roth
2022-03-07 21:53 ` [PATCH v12 43.1/46] virt: Add SEV-SNP guest driver Brijesh Singh
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