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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/arm64/kernel/machine_kexec_file.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm64/kernel/machine_kexec_file.c')
-rw-r--r--arch/arm64/kernel/machine_kexec_file.c348
1 files changed, 348 insertions, 0 deletions
diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
new file mode 100644
index 000000000..0cde47a63
--- /dev/null
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -0,0 +1,348 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * kexec_file for arm64
+ *
+ * Copyright (C) 2018 Linaro Limited
+ * Author: AKASHI Takahiro <takahiro.akashi@linaro.org>
+ *
+ * Most code is derived from arm64 port of kexec-tools
+ */
+
+#define pr_fmt(fmt) "kexec_file: " fmt
+
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/kexec.h>
+#include <linux/libfdt.h>
+#include <linux/memblock.h>
+#include <linux/of_fdt.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/vmalloc.h>
+#include <asm/byteorder.h>
+
+/* relevant device tree properties */
+#define FDT_PROP_KEXEC_ELFHDR "linux,elfcorehdr"
+#define FDT_PROP_MEM_RANGE "linux,usable-memory-range"
+#define FDT_PROP_INITRD_START "linux,initrd-start"
+#define FDT_PROP_INITRD_END "linux,initrd-end"
+#define FDT_PROP_BOOTARGS "bootargs"
+#define FDT_PROP_KASLR_SEED "kaslr-seed"
+#define FDT_PROP_RNG_SEED "rng-seed"
+#define RNG_SEED_SIZE 128
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+ &kexec_image_ops,
+ NULL
+};
+
+int arch_kimage_file_post_load_cleanup(struct kimage *image)
+{
+ vfree(image->arch.dtb);
+ image->arch.dtb = NULL;
+
+ vfree(image->arch.elf_headers);
+ image->arch.elf_headers = NULL;
+ image->arch.elf_headers_sz = 0;
+
+ return kexec_image_post_load_cleanup_default(image);
+}
+
+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;
+
+ ret = fdt_delprop(dtb, off, FDT_PROP_KEXEC_ELFHDR);
+ if (ret && ret != -FDT_ERR_NOTFOUND)
+ goto out;
+ ret = fdt_delprop(dtb, off, FDT_PROP_MEM_RANGE);
+ if (ret && ret != -FDT_ERR_NOTFOUND)
+ goto out;
+
+ if (image->type == KEXEC_TYPE_CRASH) {
+ /* add linux,elfcorehdr */
+ ret = fdt_appendprop_addrrange(dtb, 0, off,
+ FDT_PROP_KEXEC_ELFHDR,
+ image->arch.elf_headers_mem,
+ image->arch.elf_headers_sz);
+ if (ret)
+ return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
+
+ /* add linux,usable-memory-range */
+ ret = fdt_appendprop_addrrange(dtb, 0, off,
+ FDT_PROP_MEM_RANGE,
+ crashk_res.start,
+ crashk_res.end - crashk_res.start + 1);
+ if (ret)
+ return (ret == -FDT_ERR_NOSPACE ? -ENOMEM : -EINVAL);
+ }
+
+ /* 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 kaslr-seed */
+ ret = fdt_delprop(dtb, off, FDT_PROP_KASLR_SEED);
+ if (ret == -FDT_ERR_NOTFOUND)
+ ret = 0;
+ else if (ret)
+ goto out;
+
+ if (rng_is_initialized()) {
+ u64 seed = get_random_u64();
+ ret = fdt_setprop_u64(dtb, off, FDT_PROP_KASLR_SEED, seed);
+ if (ret)
+ goto out;
+ } else {
+ pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+ FDT_PROP_KASLR_SEED);
+ }
+
+ /* add rng-seed */
+ if (rng_is_initialized()) {
+ void *rng_seed;
+ ret = fdt_setprop_placeholder(dtb, off, FDT_PROP_RNG_SEED,
+ RNG_SEED_SIZE, &rng_seed);
+ if (ret)
+ goto out;
+ get_random_bytes(rng_seed, RNG_SEED_SIZE);
+ } else {
+ pr_notice("RNG is not initialised: omitting \"%s\" property\n",
+ FDT_PROP_RNG_SEED);
+ }
+
+out:
+ if (ret)
+ return (ret == -FDT_ERR_NOSPACE) ? -ENOMEM : -EINVAL;
+
+ return 0;
+}
+
+/*
+ * More space needed so that we can add initrd, bootargs, kaslr-seed,
+ * rng-seed, userable-memory-range and elfcorehdr.
+ */
+#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) {
+ vfree(buf);
+ 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;
+ }
+}
+
+static int prepare_elf_headers(void **addr, unsigned long *sz)
+{
+ struct crash_mem *cmem;
+ unsigned int nr_ranges;
+ int ret;
+ u64 i;
+ phys_addr_t start, end;
+
+ nr_ranges = 1; /* for exclusion of crashkernel region */
+ for_each_mem_range(i, &start, &end)
+ nr_ranges++;
+
+ cmem = kmalloc(struct_size(cmem, ranges, nr_ranges), GFP_KERNEL);
+ if (!cmem)
+ return -ENOMEM;
+
+ cmem->max_nr_ranges = nr_ranges;
+ cmem->nr_ranges = 0;
+ for_each_mem_range(i, &start, &end) {
+ cmem->ranges[cmem->nr_ranges].start = start;
+ cmem->ranges[cmem->nr_ranges].end = end - 1;
+ cmem->nr_ranges++;
+ }
+
+ /* Exclude crashkernel region */
+ ret = crash_exclude_mem_range(cmem, crashk_res.start, crashk_res.end);
+
+ if (!ret)
+ ret = crash_prepare_elf64_headers(cmem, true, addr, sz);
+
+ kfree(cmem);
+ return ret;
+}
+
+/*
+ * Tries to add the initrd and DTB to the image. If it is not possible to find
+ * valid locations, this function will undo changes to the image and return non
+ * zero.
+ */
+int load_other_segments(struct kimage *image,
+ unsigned long kernel_load_addr,
+ unsigned long kernel_size,
+ char *initrd, unsigned long initrd_len,
+ char *cmdline)
+{
+ struct kexec_buf kbuf;
+ void *headers, *dtb = NULL;
+ unsigned long headers_sz, initrd_load_addr = 0, dtb_len,
+ orig_segments = image->nr_segments;
+ int ret = 0;
+
+ kbuf.image = image;
+ /* not allocate anything below the kernel */
+ kbuf.buf_min = kernel_load_addr + kernel_size;
+
+ /* load elf core header */
+ if (image->type == KEXEC_TYPE_CRASH) {
+ ret = prepare_elf_headers(&headers, &headers_sz);
+ if (ret) {
+ pr_err("Preparing elf core header failed\n");
+ goto out_err;
+ }
+
+ kbuf.buffer = headers;
+ kbuf.bufsz = headers_sz;
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+ kbuf.memsz = headers_sz;
+ kbuf.buf_align = SZ_64K; /* largest supported page size */
+ kbuf.buf_max = ULONG_MAX;
+ kbuf.top_down = true;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret) {
+ vfree(headers);
+ goto out_err;
+ }
+ image->arch.elf_headers = headers;
+ image->arch.elf_headers_mem = kbuf.mem;
+ image->arch.elf_headers_sz = headers_sz;
+
+ pr_debug("Loaded elf core header at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ image->arch.elf_headers_mem, kbuf.bufsz, kbuf.memsz);
+ }
+
+ /* load initrd */
+ if (initrd) {
+ kbuf.buffer = initrd;
+ kbuf.bufsz = initrd_len;
+ kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
+ kbuf.memsz = initrd_len;
+ kbuf.buf_align = 0;
+ /* within 1GB-aligned window of up to 32GB in size */
+ kbuf.buf_max = round_down(kernel_load_addr, SZ_1G)
+ + (unsigned long)SZ_1G * 32;
+ kbuf.top_down = false;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret)
+ goto out_err;
+ initrd_load_addr = kbuf.mem;
+
+ pr_debug("Loaded initrd at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ initrd_load_addr, kbuf.bufsz, 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;
+ /* not across 2MB boundary */
+ kbuf.buf_align = SZ_2M;
+ kbuf.buf_max = ULONG_MAX;
+ kbuf.top_down = true;
+
+ ret = kexec_add_buffer(&kbuf);
+ if (ret)
+ goto out_err;
+ image->arch.dtb = dtb;
+ image->arch.dtb_mem = kbuf.mem;
+
+ pr_debug("Loaded dtb at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
+ kbuf.mem, kbuf.bufsz, kbuf.memsz);
+
+ return 0;
+
+out_err:
+ image->nr_segments = orig_segments;
+ vfree(dtb);
+ return ret;
+}