Boot via EFI on arm64 and x86_64

.gitignore

@@ -1,3 +1,4 @@
+*.fd
 *.swp
 *.tar.gz
 .ccache

driver.sh

@@ -85,8 +85,15 @@ setup_variables() {
       image_name=Image.gz
       qemu="qemu-system-aarch64"
       qemu_cmdline=( -cpu cortex-a57
-                     -drive "file=images/arm64/rootfs.ext4,format=raw"
-                     -append "console=ttyAMA0 root=/dev/vda" )
+                     -drive "file=images/arm64/rootfs.ext4,format=raw,id=rootfs,if=none"
+                     -device "virtio-blk-device,drive=rootfs"
+                     -append "console=ttyAMA0 earlycon root=/dev/vda" )
+      aavmf=/usr/share/AAVMF
+      if [[ ${tree} != common && -f ${aavmf}/AAVMF_CODE.fd && -f ${aavmf}/AAVMF_VARS.fd ]]; then
+        cp ${aavmf}/AAVMF_VARS.fd images/arm64
+        qemu_cmdline+=( -drive "if=pflash,format=raw,readonly,file=${aavmf}/AAVMF_CODE.fd"
+                        -drive "if=pflash,format=raw,file=images/arm64/AAVMF_VARS.fd" )
+      fi
       export CROSS_COMPILE=aarch64-linux-gnu- ;;
 
     "mipsel")
@@ -144,9 +151,15 @@ setup_variables() {
                          -initrd "images/x86_64/rootfs.cpio" ) ;;
         *)
           config=defconfig
-          qemu_cmdline=( -drive "file=images/x86_64/rootfs.ext4,format=raw,if=ide"
-                         -append "console=ttyS0 root=/dev/sda" ) ;;
+          qemu_cmdline=( -drive "file=images/x86_64/rootfs.ext4,format=raw,if=virtio"
+                         -append "console=ttyS0 root=/dev/vda" ) ;;
       esac
+      ovmf=/usr/share/OVMF
+      if [[ ${tree} != common && -f ${ovmf}/OVMF_CODE.fd && -f ${ovmf}/OVMF_VARS.fd ]]; then
+        cp ${ovmf}/OVMF_VARS.fd images/x86_64
+        qemu_cmdline+=( -drive "if=pflash,format=raw,readonly,file=${ovmf}/OVMF_CODE.fd"
+                        -drive "if=pflash,format=raw,file=images/x86_64/OVMF_VARS.fd" )
+      fi
       # Use KVM if the processor supports it (first part) and the KVM module is loaded (second part)
       [[ $(grep -c -E 'vmx|svm' /proc/cpuinfo) -gt 0 && $(lsmod 2>/dev/null | grep -c kvm) -gt 0 ]] && qemu_cmdline=( "${qemu_cmdline[@]}" -enable-kvm )
       image_name=bzImage

patches/llvm-all/linux/arm64/0001-arm64-efi-Move-variable-assignments-after-SECTIONS.patch

@@ -0,0 +1,172 @@
+From f43cc4ed67f44f22754bef5bec98bf8aad3e6e8d Mon Sep 17 00:00:00 2001
+From: Kees Cook <keescook@chromium.org>
+Date: Tue, 13 Aug 2019 16:04:50 -0700
+Subject: [PATCH] arm64/efi: Move variable assignments after SECTIONS
+
+It seems that LLVM's linker does not correctly handle variable assignments
+involving section positions that are updated during the SECTIONS
+parsing. Commit aa69fb62bea1 ("arm64/efi: Mark __efistub_stext_offset as
+an absolute symbol explicitly") ran into this too, but found a different
+workaround.
+
+However, this was not enough, as other variables were also miscalculated
+which manifested as boot failures under UEFI where __efistub__end was
+not taking the correct _end value (they should be the same):
+
+$ ld.lld -EL -maarch64elf --no-undefined -X -shared \
+	-Bsymbolic -z notext -z norelro --no-apply-dynamic-relocs \
+	-o vmlinux.lld -T poc.lds --whole-archive vmlinux.o && \
+  readelf -Ws vmlinux.lld | egrep '\b(__efistub_|)_end\b'
+368272: ffff000002218000     0 NOTYPE  LOCAL  HIDDEN    38 __efistub__end
+368322: ffff000012318000     0 NOTYPE  GLOBAL DEFAULT   38 _end
+
+$ aarch64-linux-gnu-ld.bfd -EL -maarch64elf --no-undefined -X -shared \
+	-Bsymbolic -z notext -z norelro --no-apply-dynamic-relocs \
+	-o vmlinux.bfd -T poc.lds --whole-archive vmlinux.o && \
+  readelf -Ws vmlinux.bfd | egrep '\b(__efistub_|)_end\b'
+338124: ffff000012318000     0 NOTYPE  LOCAL  DEFAULT  ABS __efistub__end
+383812: ffff000012318000     0 NOTYPE  GLOBAL DEFAULT 15325 _end
+
+To work around this, all of the __efistub_-prefixed variable assignments
+need to be moved after the linker script's SECTIONS entry. As it turns
+out, this also solves the problem fixed in commit aa69fb62bea1, so those
+changes are reverted here.
+
+Link: https://github.com/ClangBuiltLinux/linux/issues/634
+Link: https://bugs.llvm.org/show_bug.cgi?id=42990
+Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
+Signed-off-by: Kees Cook <keescook@chromium.org>
+Signed-off-by: Will Deacon <will@kernel.org>
+(am from https://git.kernel.org/arm64/c/90776dd1c427cbb4d381aa4b13338f1fb1d20f5e)
+Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
+---
+ arch/arm64/kernel/image-vars.h  | 51 +++++++++++++++++++++++++++++++++
+ arch/arm64/kernel/image.h       | 42 ---------------------------
+ arch/arm64/kernel/vmlinux.lds.S |  2 ++
+ 3 files changed, 53 insertions(+), 42 deletions(-)
+ create mode 100644 arch/arm64/kernel/image-vars.h
+
+diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h
+new file mode 100644
+index 000000000000..25a2a9b479c2
+--- /dev/null
++++ b/arch/arm64/kernel/image-vars.h
+@@ -0,0 +1,51 @@
++/* SPDX-License-Identifier: GPL-2.0-only */
++/*
++ * Linker script variables to be set after section resolution, as
++ * ld.lld does not like variables assigned before SECTIONS is processed.
++ */
++#ifndef __ARM64_KERNEL_IMAGE_VARS_H
++#define __ARM64_KERNEL_IMAGE_VARS_H
++
++#ifndef LINKER_SCRIPT
++#error This file should only be included in vmlinux.lds.S
++#endif
++
++#ifdef CONFIG_EFI
++
++__efistub_stext_offset = stext - _text;
++
++/*
++ * The EFI stub has its own symbol namespace prefixed by __efistub_, to
++ * isolate it from the kernel proper. The following symbols are legally
++ * accessed by the stub, so provide some aliases to make them accessible.
++ * Only include data symbols here, or text symbols of functions that are
++ * guaranteed to be safe when executed at another offset than they were
++ * linked at. The routines below are all implemented in assembler in a
++ * position independent manner
++ */
++__efistub_memcmp		= __pi_memcmp;
++__efistub_memchr		= __pi_memchr;
++__efistub_memcpy		= __pi_memcpy;
++__efistub_memmove		= __pi_memmove;
++__efistub_memset		= __pi_memset;
++__efistub_strlen		= __pi_strlen;
++__efistub_strnlen		= __pi_strnlen;
++__efistub_strcmp		= __pi_strcmp;
++__efistub_strncmp		= __pi_strncmp;
++__efistub_strrchr		= __pi_strrchr;
++__efistub___flush_dcache_area	= __pi___flush_dcache_area;
++
++#ifdef CONFIG_KASAN
++__efistub___memcpy		= __pi_memcpy;
++__efistub___memmove		= __pi_memmove;
++__efistub___memset		= __pi_memset;
++#endif
++
++__efistub__text			= _text;
++__efistub__end			= _end;
++__efistub__edata		= _edata;
++__efistub_screen_info		= screen_info;
++
++#endif
++
++#endif /* __ARM64_KERNEL_IMAGE_VARS_H */
+diff --git a/arch/arm64/kernel/image.h b/arch/arm64/kernel/image.h
+index 2b85c0d6fa3d..c7d38c660372 100644
+--- a/arch/arm64/kernel/image.h
++++ b/arch/arm64/kernel/image.h
+@@ -65,46 +65,4 @@
+ 	DEFINE_IMAGE_LE64(_kernel_offset_le, TEXT_OFFSET);	\
+ 	DEFINE_IMAGE_LE64(_kernel_flags_le, __HEAD_FLAGS);
+
+-#ifdef CONFIG_EFI
+-
+-/*
+- * Use ABSOLUTE() to avoid ld.lld treating this as a relative symbol:
+- * https://github.com/ClangBuiltLinux/linux/issues/561
+- */
+-__efistub_stext_offset = ABSOLUTE(stext - _text);
+-
+-/*
+- * The EFI stub has its own symbol namespace prefixed by __efistub_, to
+- * isolate it from the kernel proper. The following symbols are legally
+- * accessed by the stub, so provide some aliases to make them accessible.
+- * Only include data symbols here, or text symbols of functions that are
+- * guaranteed to be safe when executed at another offset than they were
+- * linked at. The routines below are all implemented in assembler in a
+- * position independent manner
+- */
+-__efistub_memcmp		= __pi_memcmp;
+-__efistub_memchr		= __pi_memchr;
+-__efistub_memcpy		= __pi_memcpy;
+-__efistub_memmove		= __pi_memmove;
+-__efistub_memset		= __pi_memset;
+-__efistub_strlen		= __pi_strlen;
+-__efistub_strnlen		= __pi_strnlen;
+-__efistub_strcmp		= __pi_strcmp;
+-__efistub_strncmp		= __pi_strncmp;
+-__efistub_strrchr		= __pi_strrchr;
+-__efistub___flush_dcache_area	= __pi___flush_dcache_area;
+-
+-#ifdef CONFIG_KASAN
+-__efistub___memcpy		= __pi_memcpy;
+-__efistub___memmove		= __pi_memmove;
+-__efistub___memset		= __pi_memset;
+-#endif
+-
+-__efistub__text			= _text;
+-__efistub__end			= _end;
+-__efistub__edata		= _edata;
+-__efistub_screen_info		= screen_info;
+-
+-#endif
+-
+ #endif /* __ARM64_KERNEL_IMAGE_H */
+diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S
+index 7fa008374907..803b24d2464a 100644
+--- a/arch/arm64/kernel/vmlinux.lds.S
++++ b/arch/arm64/kernel/vmlinux.lds.S
+@@ -245,6 +245,8 @@ SECTIONS
+ 	HEAD_SYMBOLS
+ }
+
++#include "image-vars.h"
++
+ /*
+  * The HYP init code and ID map text can't be longer than a page each,
+  * and should not cross a page boundary.
+-- 
+2.23.0.rc2
+