[PATCH v3 1/2] treewide: Add a flag to detect the Apple T2 chip
From: Atharva Tiwari
Date: Tue Jul 21 2026 - 02:42:52 EST
Add a flag to detect Apple T2 chips on Intel Macs.
Cache the result to avoid repeated checks. That will
be used in upcoming patches.
Signed-off-by: Atharva Tiwari <atharvatiwarilinuxdev@xxxxxxxxx>
---
arch/x86/kernel/quirks.c | 105 ++++++++++++++++++
include/linux/platform_data/x86/apple.h | 5 +
.../platform_certs/keyring_handler.h | 8 --
security/integrity/platform_certs/load_uefi.c | 38 ++-----
4 files changed, 118 insertions(+), 38 deletions(-)
diff --git a/arch/x86/kernel/quirks.c b/arch/x86/kernel/quirks.c
index a92f18db9610..300d6436060d 100644
--- a/arch/x86/kernel/quirks.c
+++ b/arch/x86/kernel/quirks.c
@@ -664,8 +664,113 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2083, quirk_intel_purley_xeon_ras
bool x86_apple_machine;
EXPORT_SYMBOL(x86_apple_machine);
+bool has_apple_t2_chip;
+EXPORT_SYMBOL(has_apple_t2_chip);
+
+static const struct dmi_system_id apple_t2_devices[] __initconst = {
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,1"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,2"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,3"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro15,4"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,1"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,2"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,3"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro16,4"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir8,1"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir8,2"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacBookAir9,1"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "Macmini8,1"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "MacPro7,1"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "iMac20,1"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "iMac20,2"),
+ },
+ },
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "iMacPro1,1"),
+ },
+ },
+ { }
+};
+
void __init early_platform_quirks(void)
{
x86_apple_machine = dmi_match(DMI_SYS_VENDOR, "Apple Inc.") ||
dmi_match(DMI_SYS_VENDOR, "Apple Computer, Inc.");
+
+ has_apple_t2_chip = dmi_check_system(apple_t2_devices);
}
diff --git a/include/linux/platform_data/x86/apple.h b/include/linux/platform_data/x86/apple.h
index 079e816c3c21..47b27dceab18 100644
--- a/include/linux/platform_data/x86/apple.h
+++ b/include/linux/platform_data/x86/apple.h
@@ -6,8 +6,13 @@
* x86_apple_machine - whether the machine is an x86 Apple Macintosh
*/
extern bool x86_apple_machine;
+/**
+ * has_apple_t2_chip - whether the machine has the Apple T2 chip
+ */
+extern bool has_apple_t2_chip;
#else
#define x86_apple_machine false
+#define has_apple_t2_chip false
#endif
#endif
diff --git a/security/integrity/platform_certs/keyring_handler.h b/security/integrity/platform_certs/keyring_handler.h
index f92895cc50f6..a355f4400179 100644
--- a/security/integrity/platform_certs/keyring_handler.h
+++ b/security/integrity/platform_certs/keyring_handler.h
@@ -45,11 +45,3 @@ efi_element_handler_t get_handler_for_code_signing_keys(const efi_guid_t *sig_ty
efi_element_handler_t get_handler_for_dbx(const efi_guid_t *sig_type);
#endif
-
-#ifndef UEFI_QUIRK_SKIP_CERT
-#define UEFI_QUIRK_SKIP_CERT(vendor, product) \
- .matches = { \
- DMI_MATCH(DMI_BOARD_VENDOR, vendor), \
- DMI_MATCH(DMI_PRODUCT_NAME, product), \
- },
-#endif
diff --git a/security/integrity/platform_certs/load_uefi.c b/security/integrity/platform_certs/load_uefi.c
index c0d6948446c3..b4096d4c828d 100644
--- a/security/integrity/platform_certs/load_uefi.c
+++ b/security/integrity/platform_certs/load_uefi.c
@@ -3,42 +3,16 @@
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/cred.h>
-#include <linux/dmi.h>
#include <linux/err.h>
#include <linux/efi.h>
#include <linux/slab.h>
#include <linux/ima.h>
+#include <linux/platform_data/x86/apple.h>
#include <keys/asymmetric-type.h>
#include <keys/system_keyring.h>
#include "../integrity.h"
#include "keyring_handler.h"
-/*
- * On T2 Macs reading the db and dbx efi variables to load UEFI Secure Boot
- * certificates causes occurrence of a page fault in Apple's firmware and
- * a crash disabling EFI runtime services. The following quirk skips reading
- * these variables.
- */
-static const struct dmi_system_id uefi_skip_cert[] = {
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,1") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,2") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,3") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro15,4") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,1") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,2") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,3") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookPro16,4") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookAir8,1") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookAir8,2") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacBookAir9,1") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "Macmini8,1") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "MacPro7,1") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "iMac20,1") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "iMac20,2") },
- { UEFI_QUIRK_SKIP_CERT("Apple Inc.", "iMacPro1,1") },
- { }
-};
-
/*
* Look to see if a UEFI variable called MokIgnoreDB exists and return true if
* it does.
@@ -165,10 +139,14 @@ static int __init load_uefi_certs(void)
unsigned long dbsize = 0, dbxsize = 0, mokxsize = 0;
efi_status_t status;
int rc = 0;
- const struct dmi_system_id *dmi_id;
- dmi_id = dmi_first_match(uefi_skip_cert);
- if (dmi_id) {
+ /*
+ * On T2 Macs reading the db and dbx efi variables to load UEFI Secure Boot
+ * certificates causes occurrence of a page fault in Apple's firmware and
+ * a crash disabling EFI runtime services. The following quirk skips reading
+ * these variables.
+ */
+ if (has_apple_t2_chip) {
pr_err("Reading UEFI Secure Boot Certs is not supported on T2 Macs.\n");
return false;
}
--
2.43.0