Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

5 files changed, 327 insertions, 0 deletions

diff --git a/arch/x86/purgatory/Makefile b/arch/x86/purgatory/Makefile
new file mode 100644
index 000000000..2cfa0caef
--- /dev/null
+++ b/arch/x86/purgatory/Makefile
@@ -0,0 +1,70 @@
+# SPDX-License-Identifier: GPL-2.0
+OBJECT_FILES_NON_STANDARD := y
+
+purgatory-y := purgatory.o stack.o setup-x86_$(BITS).o sha256.o entry64.o string.o
+
+targets += $(purgatory-y)
+PURGATORY_OBJS = $(addprefix $(obj)/,$(purgatory-y))
+
+$(obj)/string.o: $(srctree)/arch/x86/boot/compressed/string.c FORCE
+	$(call if_changed_rule,cc_o_c)
+
+$(obj)/sha256.o: $(srctree)/lib/sha256.c FORCE
+	$(call if_changed_rule,cc_o_c)
+
+LDFLAGS_purgatory.ro := -e purgatory_start -r --no-undefined -nostdlib -z nodefaultlib
+targets += purgatory.ro
+
+# Sanitizer, etc. runtimes are unavailable and cannot be linked here.
+GCOV_PROFILE	:= n
+KASAN_SANITIZE	:= n
+UBSAN_SANITIZE	:= n
+KCOV_INSTRUMENT := n
+
+# These are adjustments to the compiler flags used for objects that
+# make up the standalone purgatory.ro
+
+PURGATORY_CFLAGS_REMOVE := -mcmodel=kernel
+PURGATORY_CFLAGS := -mcmodel=large -ffreestanding -fno-zero-initialized-in-bss
+PURGATORY_CFLAGS += $(DISABLE_STACKLEAK_PLUGIN) -DDISABLE_BRANCH_PROFILING
+
+# Default KBUILD_CFLAGS can have -pg option set when FTRACE is enabled. That
+# in turn leaves some undefined symbols like __fentry__ in purgatory and not
+# sure how to relocate those.
+ifdef CONFIG_FUNCTION_TRACER
+PURGATORY_CFLAGS_REMOVE		+= $(CC_FLAGS_FTRACE)
+endif
+
+ifdef CONFIG_STACKPROTECTOR
+PURGATORY_CFLAGS_REMOVE		+= -fstack-protector
+endif
+
+ifdef CONFIG_STACKPROTECTOR_STRONG
+PURGATORY_CFLAGS_REMOVE		+= -fstack-protector-strong
+endif
+
+ifdef CONFIG_RETPOLINE
+PURGATORY_CFLAGS_REMOVE		+= $(RETPOLINE_CFLAGS)
+endif
+
+CFLAGS_REMOVE_purgatory.o	+= $(PURGATORY_CFLAGS_REMOVE)
+CFLAGS_purgatory.o		+= $(PURGATORY_CFLAGS)
+
+CFLAGS_REMOVE_sha256.o		+= $(PURGATORY_CFLAGS_REMOVE)
+CFLAGS_sha256.o			+= $(PURGATORY_CFLAGS)
+
+CFLAGS_REMOVE_string.o		+= $(PURGATORY_CFLAGS_REMOVE)
+CFLAGS_string.o			+= $(PURGATORY_CFLAGS)
+
+$(obj)/purgatory.ro: $(PURGATORY_OBJS) FORCE
+		$(call if_changed,ld)
+
+targets += kexec-purgatory.c
+
+quiet_cmd_bin2c = BIN2C   $@
+      cmd_bin2c = $(objtree)/scripts/bin2c kexec_purgatory < $< > $@
+
+$(obj)/kexec-purgatory.c: $(obj)/purgatory.ro FORCE
+	$(call if_changed,bin2c)
+
+obj-$(CONFIG_KEXEC_FILE)	+= kexec-purgatory.o
diff --git a/arch/x86/purgatory/entry64.S b/arch/x86/purgatory/entry64.S
new file mode 100644
index 000000000..d1a4291d3
--- /dev/null
+++ b/arch/x86/purgatory/entry64.S
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2003,2004  Eric Biederman (ebiederm@xmission.com)
+ * Copyright (C) 2014  Red Hat Inc.
+
+ * Author(s): Vivek Goyal <vgoyal@redhat.com>
+ *
+ * This code has been taken from kexec-tools.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+	.text
+	.balign 16
+	.code64
+	.globl entry64, entry64_regs
+
+
+entry64:
+	/* Setup a gdt that should be preserved */
+	lgdt gdt(%rip)
+
+	/* load the data segments */
+	movl    $0x18, %eax     /* data segment */
+	movl    %eax, %ds
+	movl    %eax, %es
+	movl    %eax, %ss
+	movl    %eax, %fs
+	movl    %eax, %gs
+
+	/* Setup new stack */
+	leaq    stack_init(%rip), %rsp
+	pushq   $0x10 /* CS */
+	leaq    new_cs_exit(%rip), %rax
+	pushq   %rax
+	lretq
+new_cs_exit:
+
+	/* Load the registers */
+	movq	rax(%rip), %rax
+	movq	rbx(%rip), %rbx
+	movq	rcx(%rip), %rcx
+	movq	rdx(%rip), %rdx
+	movq	rsi(%rip), %rsi
+	movq	rdi(%rip), %rdi
+	movq    rsp(%rip), %rsp
+	movq	rbp(%rip), %rbp
+	movq	r8(%rip), %r8
+	movq	r9(%rip), %r9
+	movq	r10(%rip), %r10
+	movq	r11(%rip), %r11
+	movq	r12(%rip), %r12
+	movq	r13(%rip), %r13
+	movq	r14(%rip), %r14
+	movq	r15(%rip), %r15
+
+	/* Jump to the new code... */
+	jmpq	*rip(%rip)
+
+	.section ".rodata"
+	.balign 4
+entry64_regs:
+rax:	.quad 0x0
+rcx:	.quad 0x0
+rdx:	.quad 0x0
+rbx:	.quad 0x0
+rsp:	.quad 0x0
+rbp:	.quad 0x0
+rsi:	.quad 0x0
+rdi:	.quad 0x0
+r8:	.quad 0x0
+r9:	.quad 0x0
+r10:	.quad 0x0
+r11:	.quad 0x0
+r12:	.quad 0x0
+r13:	.quad 0x0
+r14:	.quad 0x0
+r15:	.quad 0x0
+rip:	.quad 0x0
+	.size entry64_regs, . - entry64_regs
+
+	/* GDT */
+	.section ".rodata"
+	.balign 16
+gdt:
+	/* 0x00 unusable segment
+	 * 0x08 unused
+	 * so use them as gdt ptr
+	 */
+	.word gdt_end - gdt - 1
+	.quad gdt
+	.word 0, 0, 0
+
+	/* 0x10 4GB flat code segment */
+	.word 0xFFFF, 0x0000, 0x9A00, 0x00AF
+
+	/* 0x18 4GB flat data segment */
+	.word 0xFFFF, 0x0000, 0x9200, 0x00CF
+gdt_end:
+stack:	.quad   0, 0
+stack_init:
diff --git a/arch/x86/purgatory/purgatory.c b/arch/x86/purgatory/purgatory.c
new file mode 100644
index 000000000..7971f7a8a
--- /dev/null
+++ b/arch/x86/purgatory/purgatory.c
@@ -0,0 +1,78 @@
+/*
+ * purgatory: Runs between two kernels
+ *
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * Author:
+ *       Vivek Goyal <vgoyal@redhat.com>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+#include <linux/bug.h>
+#include <linux/sha256.h>
+#include <asm/purgatory.h>
+
+#include "../boot/string.h"
+
+unsigned long purgatory_backup_dest __section(.kexec-purgatory);
+unsigned long purgatory_backup_src __section(.kexec-purgatory);
+unsigned long purgatory_backup_sz __section(.kexec-purgatory);
+
+u8 purgatory_sha256_digest[SHA256_DIGEST_SIZE] __section(.kexec-purgatory);
+
+struct kexec_sha_region purgatory_sha_regions[KEXEC_SEGMENT_MAX] __section(.kexec-purgatory);
+
+/*
+ * On x86, second kernel requries first 640K of memory to boot. Copy
+ * first 640K to a backup region in reserved memory range so that second
+ * kernel can use first 640K.
+ */
+static int copy_backup_region(void)
+{
+	if (purgatory_backup_dest) {
+		memcpy((void *)purgatory_backup_dest,
+		       (void *)purgatory_backup_src, purgatory_backup_sz);
+	}
+	return 0;
+}
+
+static int verify_sha256_digest(void)
+{
+	struct kexec_sha_region *ptr, *end;
+	u8 digest[SHA256_DIGEST_SIZE];
+	struct sha256_state sctx;
+
+	sha256_init(&sctx);
+	end = purgatory_sha_regions + ARRAY_SIZE(purgatory_sha_regions);
+
+	for (ptr = purgatory_sha_regions; ptr < end; ptr++)
+		sha256_update(&sctx, (uint8_t *)(ptr->start), ptr->len);
+
+	sha256_final(&sctx, digest);
+
+	if (memcmp(digest, purgatory_sha256_digest, sizeof(digest)))
+		return 1;
+
+	return 0;
+}
+
+void purgatory(void)
+{
+	int ret;
+
+	ret = verify_sha256_digest();
+	if (ret) {
+		/* loop forever */
+		for (;;)
+			;
+	}
+	copy_backup_region();
+}
+
+/*
+ * Defined in order to reuse memcpy() and memset() from
+ * arch/x86/boot/compressed/string.c
+ */
+void warn(const char *msg) {}
diff --git a/arch/x86/purgatory/setup-x86_64.S b/arch/x86/purgatory/setup-x86_64.S
new file mode 100644
index 000000000..dfae9b9e6
--- /dev/null
+++ b/arch/x86/purgatory/setup-x86_64.S
@@ -0,0 +1,59 @@
+/*
+ * purgatory:  setup code
+ *
+ * Copyright (C) 2003,2004  Eric Biederman (ebiederm@xmission.com)
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * This code has been taken from kexec-tools.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+#include <asm/purgatory.h>
+
+	.text
+	.globl purgatory_start
+	.balign 16
+purgatory_start:
+	.code64
+
+	/* Load a gdt so I know what the segment registers are */
+	lgdt	gdt(%rip)
+
+	/* load the data segments */
+	movl	$0x18, %eax	/* data segment */
+	movl	%eax, %ds
+	movl	%eax, %es
+	movl	%eax, %ss
+	movl	%eax, %fs
+	movl	%eax, %gs
+
+	/* Setup a stack */
+	leaq	lstack_end(%rip), %rsp
+
+	/* Call the C code */
+	call purgatory
+	jmp	entry64
+
+	.section ".rodata"
+	.balign 16
+gdt:	/* 0x00 unusable segment
+	 * 0x08 unused
+	 * so use them as the gdt ptr
+	 */
+	.word	gdt_end - gdt - 1
+	.quad	gdt
+	.word	0, 0, 0
+
+	/* 0x10 4GB flat code segment */
+	.word	0xFFFF, 0x0000, 0x9A00, 0x00AF
+
+	/* 0x18 4GB flat data segment */
+	.word	0xFFFF, 0x0000, 0x9200, 0x00CF
+gdt_end:
+
+	.bss
+	.balign 4096
+lstack:
+	.skip 4096
+lstack_end:
diff --git a/arch/x86/purgatory/stack.S b/arch/x86/purgatory/stack.S
new file mode 100644
index 000000000..50a4147f9
--- /dev/null
+++ b/arch/x86/purgatory/stack.S
@@ -0,0 +1,19 @@
+/*
+ * purgatory:  stack
+ *
+ * Copyright (C) 2014 Red Hat Inc.
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2.  See the file COPYING for more details.
+ */
+
+	/* A stack for the loaded kernel.
+	 * Separate and in the data section so it can be prepopulated.
+	 */
+	.data
+	.balign 4096
+	.globl stack, stack_end
+
+stack:
+	.skip 4096
+stack_end: