[PATCH v2 5/5] arm: kexec_file: load zImage or uImage, initrd and dtb

From: Åukasz Stelmach
Date: Tue Jun 02 2020 - 12:17:50 EST


This is kexec_file_load implementation for ARM. It loads zImage and
initrd from file descripters and resuses DTB.

Most code is derived from arm64 kexec_file_load implementation
and from kexec-tools.

Cc: AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
Signed-off-by: Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
---
arch/arm/Kconfig | 25 ++++
arch/arm/include/asm/image.h | 26 ++++
arch/arm/include/asm/kexec.h | 14 ++
arch/arm/kernel/Makefile | 5 +-
arch/arm/kernel/kexec_uimage.c | 80 ++++++++++
arch/arm/kernel/kexec_zimage.c | 194 ++++++++++++++++++++++++
arch/arm/kernel/machine_kexec.c | 11 +-
arch/arm/kernel/machine_kexec_file.c | 211 +++++++++++++++++++++++++++
8 files changed, 561 insertions(+), 5 deletions(-)
create mode 100644 arch/arm/kernel/kexec_uimage.c
create mode 100644 arch/arm/kernel/kexec_zimage.c
create mode 100644 arch/arm/kernel/machine_kexec_file.c

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index c77c93c485a0..c592c58e78f1 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1917,6 +1917,31 @@ config KEXEC
is properly shutdown, so do not be surprised if this code does not
initially work for you.

+config KEXEC_FILE
+ bool "Kexec file based system call (EXPERIMENTAL)"
+ depends on (!SMP || PM_SLEEP_SMP)
+ depends on USE_OF
+ select KEXEC_CORE
+ select CRC32
+ help
+ This is new version of kexec system call. This system call is
+ file based and takes file descriptors as system call argument
+ for kernel and initramfs as opposed to list of segments as
+ accepted by previous system call.
+
+ The kernel to be loaded MUST support Flattened Device Tree
+ (selected with CONFIG_USE_OF).
+
+config KEXEC_FILE_UIMAGE
+ bool "Load legacy uImage files with kexec_file_load() (EXPERIMENTAL)"
+ depends on KEXEC_FILE
+ default n
+ help
+ This options enables support for the legacy uImage files as
+ created by mkimage. These are not the new FIT files.
+
+ If unsure say N.
+
config ATAGS_PROC
bool "Export atags in procfs"
depends on ATAGS && KEXEC
diff --git a/arch/arm/include/asm/image.h b/arch/arm/include/asm/image.h
index 55b51faa6b7e..596b32952958 100644
--- a/arch/arm/include/asm/image.h
+++ b/arch/arm/include/asm/image.h
@@ -8,8 +8,13 @@
(((x) >> 8) & 0x0000ff00) | \
(((x) << 8) & 0x00ff0000) | \
(((x) << 24) & 0xff000000))
+#define UIMAGE_MAGIC(x) (x)
#else
#define ZIMAGE_MAGIC(x) (x)
+#define UIMAGE_MAGIC(x) ((((x) >> 24) & 0x000000ff) | \
+ (((x) >> 8) & 0x0000ff00) | \
+ (((x) << 8) & 0x00ff0000) | \
+ (((x) << 24) & 0xff000000))
#endif

#define ARM_ZIMAGE_MAGIC1 ZIMAGE_MAGIC(0x016f2818)
@@ -17,6 +22,12 @@
#define ARM_ZIMAGE_MAGIC3 ZIMAGE_MAGIC(0x5a534c4b)
#define ARM_ZIMAGE_MAGIC4 ZIMAGE_MAGIC(0x5a534344)

+#define ARM_UIMAGE_MAGIC UIMAGE_MAGIC(0x27051956)
+#define ARM_UIMAGE_NAME_LEN 32
+#define ARM_UIMAGE_TYPE_KERNEL 2
+#define ARM_UIMAGE_TYPE_KERNEL_NOLOAD 14
+#define ARM_UIMAGE_ARCH_ARM 2
+
#ifndef __ASSEMBLY__

#include <linux/types.h>
@@ -33,6 +44,21 @@ struct arm_zimage_header {
__le32 extension_tag_offset;
};

+struct arm_uimage_header {
+ __be32 magic;
+ __be32 hdr_crc;
+ __be32 time;
+ __be32 size;
+ __be32 load;
+ __be32 entry;
+ __be32 crc;
+ __u8 os;
+ __u8 arch;
+ __u8 type;
+ __u8 comp;
+ __u8 name[ARM_UIMAGE_NAME_LEN];
+};
+
struct arm_zimage_tag {
struct tag_header hdr;
union {
diff --git a/arch/arm/include/asm/kexec.h b/arch/arm/include/asm/kexec.h
index 22751b5b5735..fda35afa7195 100644
--- a/arch/arm/include/asm/kexec.h
+++ b/arch/arm/include/asm/kexec.h
@@ -83,6 +83,20 @@ static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
}
#define boot_pfn_to_page boot_pfn_to_page

+#ifdef CONFIG_KEXEC_FILE
+
+extern const struct kexec_file_ops kexec_zimage_ops;
+extern const struct kexec_file_ops kexec_uimage_ops;
+
+struct kimage;
+
+extern int load_other_segments(struct kimage *image,
+ unsigned long kernel_load_addr, unsigned long kernel_size,
+ char *initrd, unsigned long initrd_len,
+ unsigned long initrd_offset, char *cmdline);
+
+#endif /* CONFIG_KEXEC_FILE */
+
#endif /* __ASSEMBLY__ */

#endif /* CONFIG_KEXEC */
diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
index 89e5d864e923..453ecf7305e2 100644
--- a/arch/arm/kernel/Makefile
+++ b/arch/arm/kernel/Makefile
@@ -3,6 +3,7 @@
# Makefile for the linux kernel.
#

+CFLAGS_kexec_zimage.o := -DTEXT_OFFSET=$(TEXT_OFFSET)
CPPFLAGS_vmlinux.lds := -DTEXT_OFFSET=$(TEXT_OFFSET)
AFLAGS_head.o := -DTEXT_OFFSET=$(TEXT_OFFSET)

@@ -56,7 +57,9 @@ obj-$(CONFIG_FUNCTION_TRACER) += entry-ftrace.o
obj-$(CONFIG_DYNAMIC_FTRACE) += ftrace.o insn.o patch.o
obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += ftrace.o insn.o patch.o
obj-$(CONFIG_JUMP_LABEL) += jump_label.o insn.o patch.o
-obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o
+obj-$(CONFIG_KEXEC_CORE) += machine_kexec.o relocate_kernel.o
+obj-$(CONFIG_KEXEC_FILE) += machine_kexec_file.o kexec_zimage.o
+obj-$(CONFIG_KEXEC_FILE_UIMAGE) += kexec_uimage.o
# Main staffs in KPROBES are in arch/arm/probes/ .
obj-$(CONFIG_KPROBES) += patch.o insn.o
obj-$(CONFIG_OABI_COMPAT) += sys_oabi-compat.o
diff --git a/arch/arm/kernel/kexec_uimage.c b/arch/arm/kernel/kexec_uimage.c
new file mode 100644
index 000000000000..47033574e24e
--- /dev/null
+++ b/arch/arm/kernel/kexec_uimage.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Kexec uImage loader
+ *
+ * Copyright (C) 2020 Samsung Electronics
+ * Author: Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
+ */
+
+#define pr_fmt(fmt) "kexec_file(uImage): " fmt
+
+#include <asm/image.h>
+#include <linux/crc32.h>
+#include <linux/err.h>
+#include <linux/kexec.h>
+
+#define crc32_ones(crc, buf, len) \
+ (crc32(crc ^ 0xffffffff, buf, len) ^ 0xffffffff)
+
+static int uimage_probe(const char *uimage_buf, unsigned long uimage_len)
+{
+ const struct arm_uimage_header *h =
+ (struct arm_uimage_header *) uimage_buf;
+ struct arm_uimage_header uhdr;
+ unsigned long zoff = sizeof(struct arm_uimage_header);
+ uint32_t crc;
+
+ if (h->magic != ARM_UIMAGE_MAGIC)
+ return -EINVAL;
+
+ if (h->type != ARM_UIMAGE_TYPE_KERNEL &&
+ h->type != ARM_UIMAGE_TYPE_KERNEL_NOLOAD){
+ pr_debug("Invalid image type: %d\n", h->type);
+ return -EINVAL;
+ }
+
+ if (h->arch != ARM_UIMAGE_ARCH_ARM) {
+ pr_debug("Invalidy image arch: %d\n", h->arch);
+ return -EINVAL;
+ }
+
+ memcpy((char *)&uhdr, h, sizeof(uhdr));
+ crc = be32_to_cpu(uhdr.hdr_crc);
+ uhdr.hdr_crc = 0;
+
+ if (crc32_ones(0, (char *)&uhdr, sizeof(uhdr)) != crc) {
+ pr_debug("Corrupt header, CRC do not match\n");
+ return -EINVAL;
+ }
+
+ crc = be32_to_cpu(uhdr.crc);
+ if (crc32_ones(0, uimage_buf + zoff, uimage_len - zoff) != crc) {
+ pr_debug("Corrupt zImage, CRC do not match\n");
+ return -EINVAL;
+ }
+
+ return kexec_zimage_ops.probe(uimage_buf + zoff,
+ uimage_len - zoff);
+}
+
+static void *uimage_load(struct kimage *image,
+ char *uimage, unsigned long uimage_len,
+ char *initrd, unsigned long initrd_len,
+ char *cmdline, unsigned long cmdline_len)
+{
+ const struct arm_uimage_header *h =
+ (struct arm_uimage_header *) uimage;
+ unsigned long zimage_offset = sizeof(struct arm_uimage_header);
+
+ pr_debug("Loading uImage");
+ return kexec_zimage_ops.load(image,
+ uimage + zimage_offset,
+ uimage_len - zimage_offset,
+ initrd, initrd_len,
+ cmdline, cmdline_len);
+}
+
+const struct kexec_file_ops kexec_uimage_ops = {
+ .probe = uimage_probe,
+ .load = uimage_load,
+};
diff --git a/arch/arm/kernel/kexec_zimage.c b/arch/arm/kernel/kexec_zimage.c
new file mode 100644
index 000000000000..586b623ed91d
--- /dev/null
+++ b/arch/arm/kernel/kexec_zimage.c
@@ -0,0 +1,194 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Kexec zImage loader
+ *
+ * Copyright (C) 2016-2018 Russel King
+ * Copyright (C) 2020 Samsung Electronics
+ * Authors:
+ * Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
+ * Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
+ */
+
+#define pr_fmt(fmt) "kexec_file(zImage): " fmt
+
+#include <asm/image.h>
+#include <asm/unaligned.h>
+#include <linux/err.h>
+#include <linux/kexec.h>
+#include <linux/memblock.h>
+
+#define byte_size(t) ((t)->hdr.size << 2)
+
+/*
+ * This function and several pieces below have been taken from
+ * kexec-tools/kexec/arch/arm/kexec-zImage-arm.c
+ */
+static const void *find_extension_tag(const char *buf,
+ unsigned long len,
+ uint32_t tag_id)
+{
+ const struct arm_zimage_header *h = (const struct arm_zimage_header *)buf;
+ const struct arm_zimage_tag *tag;
+ uint32_t offset, size;
+ uint32_t max = len - sizeof(struct tag_header);
+
+ if (len < sizeof(*h) ||
+ h->magic != ARM_ZIMAGE_MAGIC1 ||
+ h->magic2 != ARM_ZIMAGE_MAGIC2)
+ return NULL;
+
+ for (offset = h->extension_tag_offset;
+ (tag = (void *)(buf + offset)) != NULL &&
+ offset < max &&
+ (size = le32_to_cpu(byte_size(tag))) != 0 &&
+ offset + size < len;
+ offset += size) {
+ pr_debug(" offset 0x%08x tag 0x%08x size %u\n",
+ offset, le32_to_cpu(tag->hdr.tag), size);
+ if (tag->hdr.tag == tag_id)
+ return tag;
+ }
+
+ return NULL;
+}
+
+static int zimage_probe(const char *kernel_buf, unsigned long kernel_len)
+{
+ const struct arm_zimage_header *h =
+ (struct arm_zimage_header *)(kernel_buf);
+
+ if (!h || (kernel_len < sizeof(*h)))
+ return -EINVAL;
+
+ if ((h->magic != ARM_ZIMAGE_MAGIC1) ||
+ (h->magic2 != ARM_ZIMAGE_MAGIC2))
+ return -EINVAL;
+
+ return 0;
+}
+
+
+#if defined(DEBUG)
+#define debug_offsets() ({ \
+ pr_debug("Image offsets:\n"); \
+ pr_debug(" kernel 0x%08lx 0x%08lx\n", kernel_offset, kernel_len); \
+ pr_debug(" zimage 0x%08lx 0x%08lx\n", zimage_offset, zimage_len); \
+ pr_debug(" initrd 0x%08lx 0x%08lx\n", initrd_offset, initrd_len); \
+})
+#else
+#define debug_offsets()
+#endif
+
+static void *zimage_load(struct kimage *image,
+ char *zimage, unsigned long zimage_len,
+ char *initrd, unsigned long initrd_len,
+ char *cmdline, unsigned long cmdline_len)
+{
+ struct arm_zimage_header *h;
+ struct kexec_buf kbuf;
+ struct kexec_segment *zimage_segment;
+ const struct arm_zimage_tag *tag;
+ int ret = -EINVAL;
+
+ unsigned long zimage_mem = 0x20000; /* malloc 64kB + stack 4 kB + some bss */
+ unsigned long kernel_len = zimage_len * 5; /* 5:1 compression */
+ unsigned long kernel_offset = memblock_start_of_DRAM() +
+ ALIGN(TEXT_OFFSET, PAGE_SIZE);
+ unsigned long zimage_offset = kernel_offset +
+ ALIGN(kernel_len, PAGE_SIZE);
+ unsigned long initrd_offset = zimage_offset +
+ ALIGN(zimage_len + zimage_mem, PAGE_SIZE);
+
+ if (image->type == KEXEC_TYPE_CRASH) {
+ kernel_offset += crashk_res.start;
+ zimage_offset += crashk_res.start;
+ initrd_offset += crashk_res.start;
+ }
+ debug_offsets();
+
+ h = (struct arm_zimage_header *)zimage;
+
+ tag = find_extension_tag(zimage, zimage_len, ZIMAGE_TAG_KRNL_SIZE);
+ if (tag) {
+ uint32_t *p = (void *)zimage +
+ le32_to_cpu(tag->u.krnl_size.size_ptr);
+ uint32_t edata_size = le32_to_cpu(get_unaligned(p));
+ uint32_t bss_size = le32_to_cpu(tag->u.krnl_size.bss_size);
+
+ kernel_len = edata_size + bss_size;
+
+ pr_debug("Decompressed kernel sizes:\n");
+ pr_debug(" text+data 0x%08lx bss 0x%08lx total 0x%08lx\n",
+ (unsigned long)edata_size,
+ (unsigned long)bss_size,
+ (unsigned long)kernel_len);
+
+ zimage_offset = kernel_offset + ALIGN(edata_size, PAGE_SIZE);
+ initrd_offset = zimage_offset +
+ max(ALIGN(zimage_len + 0x20000, PAGE_SIZE),
+ ALIGN((unsigned long)bss_size, PAGE_SIZE));
+ debug_offsets();
+ }
+
+ tag = find_extension_tag(zimage, zimage_len,
+ ZIMAGE_TAG_ZIMAGE_MEM);
+ if (tag) {
+ uint32_t zimage_mem = le32_to_cpu(tag->u.zimage_mem);
+
+ pr_debug("Decompressor requires %d bytes of memory\n", zimage_mem);
+
+ initrd_offset = max(ALIGN(zimage_offset + zimage_len + zimage_mem, PAGE_SIZE),
+ ALIGN(kernel_offset + kernel_len, PAGE_SIZE));
+ debug_offsets();
+ }
+
+ /*
+ * zImage MUST be loaded into the first 128 MiB of physical
+ * memory for proper memory detection. Should the uncompressed
+ * kernel be larger than 128 MiB, zImage relocation becomes
+ * unavoidable and it is best to rely on the relocation code.
+ */
+ if (((zimage_offset - kernel_offset) + PAGE_SIZE + 0x8000) >= SZ_128M) {
+ pr_debug("The kernel is too big (%ld MiB) to avoid "
+ "zImage relocation. Loading zimage at 0x%08lx\n",
+ ((zimage_offset - kernel_offset) >> 20),
+ kernel_offset);
+ zimage_offset = kernel_offset;
+ }
+
+ kbuf.image = image;
+ kbuf.top_down = false;
+
+ kbuf.buf_min = zimage_offset;
+ kbuf.buf_max = ULONG_MAX;
+ kbuf.buffer = zimage;
+ kbuf.bufsz = zimage_len;
+ kbuf.buf_align = PAGE_SIZE;
+
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+ kbuf.memsz = zimage_len;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret)
+ return ERR_PTR(ret);
+
+ pr_debug("Loaded zImage at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ kbuf.mem, kbuf.bufsz, kbuf.memsz);
+
+ initrd_offset += kbuf.mem - zimage_offset;
+ debug_offsets();
+
+ zimage_segment = &image->segment[image->nr_segments - 1];
+ image->start = zimage_segment->mem;
+
+ ret = load_other_segments(image,
+ zimage_segment->mem, zimage_segment->memsz,
+ initrd, initrd_len, initrd_offset,
+ cmdline);
+ return ERR_PTR(ret);
+}
+
+const struct kexec_file_ops kexec_zimage_ops = {
+ .probe = zimage_probe,
+ .load = zimage_load,
+};
diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c
index c10a2dfd53d1..2e4780efabb4 100644
--- a/arch/arm/kernel/machine_kexec.c
+++ b/arch/arm/kernel/machine_kexec.c
@@ -93,10 +93,13 @@ int machine_kexec_prepare(struct kimage *image)
current_segment->memsz))
return -EINVAL;

- err = get_user(header, (__be32*)current_segment->buf);
- if (err)
- return err;
-
+ if (image->file_mode) {
+ header = *(__be32 *)current_segment->buf;
+ } else {
+ err = get_user(header, (__be32 *)current_segment->buf);
+ if (err)
+ return err;
+ }
if (header == cpu_to_be32(OF_DT_HEADER))
image->arch.kernel_r2 = current_segment->mem;
}
diff --git a/arch/arm/kernel/machine_kexec_file.c b/arch/arm/kernel/machine_kexec_file.c
new file mode 100644
index 000000000000..a632d351602c
--- /dev/null
+++ b/arch/arm/kernel/machine_kexec_file.c
@@ -0,0 +1,211 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * kexec_file for arm
+ *
+ * Copyright (C) 2018 Linaro Limited
+ * Copyright (C) 2020 Samsung Electronics
+ * Authors:
+ * AKASHI Takahiro <takahiro.akashi@xxxxxxxxxx>
+ * Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
+ *
+ */
+
+#define pr_fmt(fmt) "kexec_file: " fmt
+
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/of_fdt.h>
+#include <linux/random.h>
+
+/* relevant device tree properties */
+#define FDT_PROP_INITRD_START "linux,initrd-start"
+#define FDT_PROP_INITRD_END "linux,initrd-end"
+#define FDT_PROP_BOOTARGS "bootargs"
+#define FDT_PROP_RNG_SEED "rng-seed"
+
+static int setup_dtb(struct kimage *image,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ char *cmdline, void *dtb)
+{
+ int off, ret;
+
+ ret = fdt_path_offset(dtb, "/chosen");
+ if (ret < 0)
+ goto out;
+
+ off = ret;
+
+ /* add bootargs */
+ if (cmdline) {
+ ret = fdt_setprop_string(dtb, off, FDT_PROP_BOOTARGS, cmdline);
+ if (ret)
+ goto out;
+ } else {
+ ret = fdt_delprop(dtb, off, FDT_PROP_BOOTARGS);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+ }
+
+ /* add initrd-* */
+ if (initrd_load_addr) {
+ ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_START,
+ initrd_load_addr);
+ if (ret)
+ goto out;
+
+ ret = fdt_setprop_u64(dtb, off, FDT_PROP_INITRD_END,
+ initrd_load_addr + initrd_len);
+ if (ret)
+ goto out;
+ } else {
+ ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_START);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+
+ ret = fdt_delprop(dtb, off, FDT_PROP_INITRD_END);
+ if (ret && (ret != -FDT_ERR_NOTFOUND))
+ goto out;
+ }
+
+ /* add rng-seed */
+ if (rng_is_initialized()) {
+ char seed[128];
+ get_random_bytes(seed, sizeof(seed));
+
+ ret = fdt_setprop(dtb, off, FDT_PROP_RNG_SEED,
+ seed, sizeof(seed));
+ if (ret)
+ goto out;
+ } else {
+ pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+ FDT_PROP_RNG_SEED);
+ ret = 0;
+ }
+
+out:
+ if (ret)
+ return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
+
+ return 0;
+}
+/*
+ * More space needed so that we can add initrd, bootargs and kaslr-seed.
+ */
+#define DTB_EXTRA_SPACE 0x1000
+
+static int create_dtb(struct kimage *image,
+ unsigned long initrd_load_addr, unsigned long initrd_len,
+ char *cmdline, void **dtb)
+{
+ void *buf;
+ size_t buf_size;
+ size_t cmdline_len;
+ int ret;
+
+ cmdline_len = cmdline ? strlen(cmdline) : 0;
+ buf_size = fdt_totalsize(initial_boot_params)
+ + cmdline_len + DTB_EXTRA_SPACE;
+
+ for (;;) {
+ buf = vmalloc(buf_size);
+ if (!buf)
+ return -ENOMEM;
+
+ /* duplicate a device tree blob */
+ ret = fdt_open_into(initial_boot_params, buf, buf_size);
+ if (ret)
+ return -EINVAL;
+
+ ret = setup_dtb(image, initrd_load_addr, initrd_len,
+ cmdline, buf);
+ if (ret) {
+ vfree(buf);
+ if (ret == -ENOMEM) {
+ /* unlikely, but just in case */
+ buf_size += DTB_EXTRA_SPACE;
+ continue;
+ } else {
+ return ret;
+ }
+ }
+
+ /* trim it */
+ fdt_pack(buf);
+ *dtb = buf;
+
+ return 0;
+ }
+}
+
+int load_other_segments(struct kimage *image,
+ unsigned long zimage_load_addr,
+ unsigned long zimage_len,
+ char *initrd,
+ unsigned long initrd_len,
+ unsigned long initrd_offset,
+ char *cmdline)
+{
+ struct kexec_buf kbuf;
+ void *dtb = NULL;
+ unsigned long initrd_load_addr = 0;
+ unsigned long dtb_len;
+ int ret = 0;
+
+ kbuf.image = image;
+ /* not allocate anything below the kernel */
+ kbuf.buf_min = initrd_offset;
+ if (initrd) {
+ kbuf.buffer = initrd;
+ kbuf.bufsz = initrd_len;
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+ kbuf.memsz = initrd_len;
+ kbuf.buf_align = PAGE_SIZE;
+ kbuf.buf_max = ULONG_MAX;
+ kbuf.top_down = false;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret)
+ goto out_err;
+
+ pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ kbuf.mem, kbuf.bufsz, kbuf.memsz);
+
+ initrd_load_addr = kbuf.mem;
+ kbuf.buf_min = initrd_load_addr + kbuf.memsz;
+ }
+
+ /* load dtb */
+ ret = create_dtb(image, initrd_load_addr, initrd_len, cmdline, &dtb);
+ if (ret) {
+ pr_err("Preparing for new dtb failed\n");
+ goto out_err;
+ }
+
+ dtb_len = fdt_totalsize(dtb);
+ kbuf.buffer = dtb;
+ kbuf.bufsz = dtb_len;
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+ kbuf.memsz = dtb_len;
+ kbuf.buf_align = PAGE_SIZE;
+ kbuf.buf_max = ULONG_MAX;
+ kbuf.top_down = false;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret)
+ goto out_err;
+
+ pr_debug("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ kbuf.mem, kbuf.bufsz, kbuf.memsz);
+ return 0;
+out_err:
+ vfree(dtb);
+ return ret;
+}
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+#ifdef CONFIG_KEXEC_FILE_UIMAGE
+ &kexec_uimage_ops,
+#endif
+ &kexec_zimage_ops,
+ NULL
+};
--
2.26.2