From: Peter Jones <pjones(a)redhat.com>
efi: x86: Set the NX-compatibility flag in the PE header
Following Baskov Evgeniy's "Handle UEFI NX-restricted page tables"
patches, it's safe to set this compatibility flag to let loaders know
they don't need to make special accommodations for kernel to load if
pre-boot NX is enabled.
Signed-off-by: Peter Jones <pjones(a)redhat.com>
Link:
https://lore.kernel.org/all/20220329184743.798513-1-pjones@redhat.com/
Signed-off-by: Ard Biesheuvel <ardb(a)kernel.org>
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index blahblah..blahblah 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -163,7 +163,11 @@ extra_header_fields:
.long 0x200 # SizeOfHeaders
.long 0 # CheckSum
.word IMAGE_SUBSYSTEM_EFI_APPLICATION # Subsystem (EFI application)
+#ifdef CONFIG_DXE_MEM_ATTRIBUTES
+ .word IMAGE_DLL_CHARACTERISTICS_NX_COMPAT # DllCharacteristics
+#else
.word 0 # DllCharacteristics
+#endif
#ifdef CONFIG_X86_32
.long 0 # SizeOfStackReserve
.long 0 # SizeOfStackCommit
--
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/1771