--- v18
+++ v19
@@ -1,266 +1,338 @@
From: Rob Herring <robh@kernel.org>
-The code for setting up the /chosen node in the device tree
-and updating the memory reservation for the next kernel has been
-moved to of_kexec_alloc_and_setup_fdt() defined in "drivers/of/kexec.c".
-
-Use the common of_kexec_alloc_and_setup_fdt() to setup the device tree
-and update the memory reservation for kexec for powerpc.
+Both arm64 and powerpc do essentially the same FDT /chosen setup for
+kexec. The differences are either omissions that arm64 should have
+or additional properties that will be ignored. The setup code can be
+combined and shared by both powerpc and arm64.
+
+The differences relative to the arm64 version:
+ - If /chosen doesn't exist, it will be created (should never happen).
+ - Any old dtb and initrd reserved memory will be released.
+ - The new initrd and elfcorehdr are marked reserved.
+ - "linux,booted-from-kexec" is set.
+
+The differences relative to the powerpc version:
+ - "kaslr-seed" and "rng-seed" may be set.
+ - "linux,elfcorehdr" is set.
+ - Any existing "linux,usable-memory-range" is removed.
+
+Combine the code for setting up the /chosen node in the FDT and updating
+the memory reservation for kexec, for powerpc and arm64, in
+of_kexec_alloc_and_setup_fdt() and move it to "drivers/of/kexec.c".
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
+Fixes: 33488dc4d61f ("of: Add a common kexec FDT setup function")
+Reported-by: kernel test robot <lkp@intel.com>
---
- arch/powerpc/include/asm/kexec.h | 1 +
- arch/powerpc/kexec/elf_64.c | 30 ++++---
- arch/powerpc/kexec/file_load.c | 132 +-----------------------------
- arch/powerpc/kexec/file_load_64.c | 3 +
- 4 files changed, 26 insertions(+), 140 deletions(-)
-
-diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
-index 4d9b250cf1e6..f59946c6f9e6 100644
---- a/arch/powerpc/include/asm/kexec.h
-+++ b/arch/powerpc/include/asm/kexec.h
-@@ -111,6 +111,7 @@ struct kimage_arch {
- unsigned long elf_load_addr;
- unsigned long elf_headers_sz;
- void *elf_headers;
+ drivers/of/Makefile | 6 +
+ drivers/of/kexec.c | 265 ++++++++++++++++++++++++++++++++++++++++++++
+ include/linux/of.h | 5 +
+ 3 files changed, 276 insertions(+)
+ create mode 100644 drivers/of/kexec.c
+
+diff --git a/drivers/of/Makefile b/drivers/of/Makefile
+index 6e1e5212f058..c13b982084a3 100644
+--- a/drivers/of/Makefile
++++ b/drivers/of/Makefile
+@@ -14,4 +14,10 @@ obj-$(CONFIG_OF_RESOLVE) += resolver.o
+ obj-$(CONFIG_OF_OVERLAY) += overlay.o
+ obj-$(CONFIG_OF_NUMA) += of_numa.o
+
++ifdef CONFIG_KEXEC_FILE
++ifdef CONFIG_OF_FLATTREE
++obj-y += kexec.o
++endif
++endif
++
+ obj-$(CONFIG_OF_UNITTEST) += unittest-data/
+diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
+new file mode 100644
+index 000000000000..8fa8946cda42
+--- /dev/null
++++ b/drivers/of/kexec.c
+@@ -0,0 +1,265 @@
++// SPDX-License-Identifier: GPL-2.0-only
++/*
++ * Copyright (C) 2020 Arm Limited
++ *
++ * Based on arch/arm64/kernel/machine_kexec_file.c:
++ * Copyright (C) 2018 Linaro Limited
++ *
++ * And arch/powerpc/kexec/file_load.c:
++ * Copyright (C) 2016 IBM Corporation
++ */
++
++#include <linux/kernel.h>
++#include <linux/kexec.h>
++#include <linux/libfdt.h>
++#include <linux/of.h>
++#include <linux/of_fdt.h>
++#include <linux/random.h>
++#include <linux/types.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
++
++/*
++ * Additional space needed for the FDT buffer so that we can add initrd,
++ * bootargs, kaslr-seed, rng-seed, useable-memory-range and elfcorehdr.
++ */
++#define FDT_EXTRA_SPACE 0x1000
++
++/**
++ * fdt_find_and_del_mem_rsv - delete memory reservation with given address and size
++ *
++ * @fdt: Flattened device tree for the current kernel.
++ * @start: Starting address of the reserved memory.
++ * @size: Size of the reserved memory.
++ *
++ * Return: 0 on success, or negative errno on error.
++ */
++static int fdt_find_and_del_mem_rsv(void *fdt, unsigned long start, unsigned long size)
++{
++ int i, ret, num_rsvs = fdt_num_mem_rsv(fdt);
++
++ for (i = 0; i < num_rsvs; i++) {
++ u64 rsv_start, rsv_size;
++
++ ret = fdt_get_mem_rsv(fdt, i, &rsv_start, &rsv_size);
++ if (ret) {
++ pr_err("Malformed device tree.\n");
++ return -EINVAL;
++ }
++
++ if (rsv_start == start && rsv_size == size) {
++ ret = fdt_del_mem_rsv(fdt, i);
++ if (ret) {
++ pr_err("Error deleting device tree reservation.\n");
++ return -EINVAL;
++ }
++
++ return 0;
++ }
++ }
++
++ return -ENOENT;
++}
++
++/*
++ * of_kexec_alloc_and_setup_fdt - Alloc and setup a new Flattened Device Tree
++ *
++ * @image: kexec image being loaded.
++ * @initrd_load_addr: Address where the next initrd will be loaded.
++ * @initrd_len: Size of the next initrd, or 0 if there will be none.
++ * @cmdline: Command line for the next kernel, or NULL if there will
++ * be none.
++ * @extra_fdt_size: Additional size for the new FDT buffer.
++ *
++ * Return: fdt on success, or NULL errno on error.
++ */
++void *of_kexec_alloc_and_setup_fdt(const struct kimage *image,
++ unsigned long initrd_load_addr,
++ unsigned long initrd_len,
++ const char *cmdline, size_t extra_fdt_size)
++{
+ void *fdt;
++ int ret, chosen_node;
++ const void *prop;
++ size_t fdt_size;
++
++ fdt_size = fdt_totalsize(initial_boot_params) +
++ (cmdline ? strlen(cmdline) : 0) +
++ FDT_EXTRA_SPACE +
++ extra_fdt_size;
++ fdt = kvmalloc(fdt_size, GFP_KERNEL);
++ if (!fdt)
++ return NULL;
++
++ ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
++ if (ret < 0) {
++ pr_err("Error %d setting up the new device tree.\n", ret);
++ goto out;
++ }
++
++ /* Remove memory reservation for the current device tree. */
++ ret = fdt_find_and_del_mem_rsv(fdt, __pa(initial_boot_params),
++ fdt_totalsize(initial_boot_params));
++ if (ret == -EINVAL) {
++ pr_err("Error removing memory reservation.\n");
++ goto out;
++ }
++
++ chosen_node = fdt_path_offset(fdt, "/chosen");
++ if (chosen_node == -FDT_ERR_NOTFOUND)
++ chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
++ "chosen");
++ if (chosen_node < 0) {
++ ret = chosen_node;
++ goto out;
++ }
++
++ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_KEXEC_ELFHDR);
++ if (ret && ret != -FDT_ERR_NOTFOUND)
++ goto out;
++ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_MEM_RANGE);
++ if (ret && ret != -FDT_ERR_NOTFOUND)
++ goto out;
++
++ /* Did we boot using an initrd? */
++ prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
++ if (prop) {
++ u64 tmp_start, tmp_end, tmp_size;
++
++ tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
++
++ prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
++ if (!prop) {
++ ret = -EINVAL;
++ goto out;
++ }
++
++ tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
++
++ /*
++ * kexec reserves exact initrd size, while firmware may
++ * reserve a multiple of PAGE_SIZE, so check for both.
++ */
++ tmp_size = tmp_end - tmp_start;
++ ret = fdt_find_and_del_mem_rsv(fdt, tmp_start, tmp_size);
++ if (ret == -ENOENT)
++ ret = fdt_find_and_del_mem_rsv(fdt, tmp_start,
++ round_up(tmp_size, PAGE_SIZE));
++ if (ret == -EINVAL)
++ goto out;
++ }
++
++ /* add initrd-* */
++ if (initrd_load_addr) {
++ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_START,
++ initrd_load_addr);
++ if (ret)
++ goto out;
++
++ ret = fdt_setprop_u64(fdt, chosen_node, FDT_PROP_INITRD_END,
++ initrd_load_addr + initrd_len);
++ if (ret)
++ goto out;
++
++ ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
++ if (ret)
++ goto out;
++
++ } else {
++ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_START);
++ if (ret && (ret != -FDT_ERR_NOTFOUND))
++ goto out;
++
++ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_INITRD_END);
++ if (ret && (ret != -FDT_ERR_NOTFOUND))
++ goto out;
++ }
++
++ if (image->type == KEXEC_TYPE_CRASH) {
++ /* add linux,elfcorehdr */
++ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
++ FDT_PROP_KEXEC_ELFHDR,
++ image->elf_load_addr,
++ image->elf_headers_sz);
++ if (ret)
++ goto out;
++
++ /*
++ * Avoid elfcorehdr from being stomped on in kdump kernel by
++ * setting up memory reserve map.
++ */
++ ret = fdt_add_mem_rsv(fdt, image->elf_load_addr,
++ image->elf_headers_sz);
++ if (ret)
++ goto out;
++
++ /* add linux,usable-memory-range */
++ ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
++ FDT_PROP_MEM_RANGE,
++ crashk_res.start,
++ crashk_res.end - crashk_res.start + 1);
++ if (ret)
++ goto out;
++ }
++
++ /* add bootargs */
++ if (cmdline) {
++ ret = fdt_setprop_string(fdt, chosen_node, FDT_PROP_BOOTARGS, cmdline);
++ if (ret)
++ goto out;
++ } else {
++ ret = fdt_delprop(fdt, chosen_node, FDT_PROP_BOOTARGS);
++ if (ret && (ret != -FDT_ERR_NOTFOUND))
++ goto out;
++ }
++
++ /* add kaslr-seed */
++ ret = fdt_delprop(fdt, chosen_node, 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(fdt, chosen_node, 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(fdt, chosen_node, 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);
++ }
++
++ ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
++
++out:
++ if (ret) {
++ kvfree(fdt);
++ fdt = NULL;
++ }
++
++ return fdt;
++}
+diff --git a/include/linux/of.h b/include/linux/of.h
+index 4b27c9a27df3..d66c915df910 100644
+--- a/include/linux/of.h
++++ b/include/linux/of.h
+@@ -560,6 +560,11 @@ int of_map_id(struct device_node *np, u32 id,
- #ifdef CONFIG_IMA_KEXEC
- phys_addr_t ima_buffer_addr;
-diff --git a/arch/powerpc/kexec/elf_64.c b/arch/powerpc/kexec/elf_64.c
-index d0e459bb2f05..87e34611f93d 100644
---- a/arch/powerpc/kexec/elf_64.c
-+++ b/arch/powerpc/kexec/elf_64.c
-@@ -19,6 +19,7 @@
- #include <linux/kexec.h>
- #include <linux/libfdt.h>
- #include <linux/module.h>
-+#include <linux/of.h>
- #include <linux/of_fdt.h>
- #include <linux/slab.h>
- #include <linux/types.h>
-@@ -29,7 +30,6 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
- unsigned long cmdline_len)
- {
- int ret;
-- unsigned int fdt_size;
- unsigned long kernel_load_addr;
- unsigned long initrd_load_addr = 0, fdt_load_addr;
- void *fdt;
-@@ -102,15 +102,10 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
- pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr);
- }
+ phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
-- fdt_size = fdt_totalsize(initial_boot_params) * 2;
-- fdt = kmalloc(fdt_size, GFP_KERNEL);
-+ fdt = of_kexec_alloc_and_setup_fdt(image, initrd_load_addr,
-+ initrd_len, cmdline,
-+ fdt_totalsize(initial_boot_params));
- if (!fdt) {
-- pr_err("Not enough memory for the device tree.\n");
-- ret = -ENOMEM;
-- goto out;
-- }
-- ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
-- if (ret < 0) {
- pr_err("Error setting up the new device tree.\n");
- ret = -EINVAL;
- goto out;
-@@ -124,13 +119,17 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
- fdt_pack(fdt);
++struct kimage;
++void *of_kexec_alloc_and_setup_fdt(const struct kimage *image,
++ unsigned long initrd_load_addr,
++ unsigned long initrd_len,
++ const char *cmdline, size_t extra_fdt_size);
+ #else /* CONFIG_OF */
- kbuf.buffer = fdt;
-- kbuf.bufsz = kbuf.memsz = fdt_size;
-+ kbuf.bufsz = kbuf.memsz = fdt_totalsize(fdt);
- kbuf.buf_align = PAGE_SIZE;
- kbuf.top_down = true;
- kbuf.mem = KEXEC_BUF_MEM_UNKNOWN;
- ret = kexec_add_buffer(&kbuf);
- if (ret)
- goto out;
-+
-+ /* FDT will be freed in arch_kimage_file_post_load_cleanup */
-+ image->arch.fdt = fdt;
-+
- fdt_load_addr = kbuf.mem;
-
- pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
-@@ -145,8 +144,15 @@ static void *elf64_load(struct kimage *image, char *kernel_buf,
- kfree(modified_cmdline);
- kexec_free_elf_info(&elf_info);
-
-- /* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
-- return ret ? ERR_PTR(ret) : fdt;
-+ /*
-+ * Once FDT buffer has been successfully passed to kexec_add_buffer(),
-+ * the FDT buffer address is saved in image->arch.fdt. In that case,
-+ * the memory cannot be freed here in case of any other error.
-+ */
-+ if (ret && !image->arch.fdt)
-+ kvfree(fdt);
-+
-+ return ret ? ERR_PTR(ret) : NULL;
- }
-
- const struct kexec_file_ops kexec_elf64_ops = {
-diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
-index f7c31daf8a2e..af5a4724a70e 100644
---- a/arch/powerpc/kexec/file_load.c
-+++ b/arch/powerpc/kexec/file_load.c
-@@ -156,135 +156,11 @@ int setup_new_fdt(const struct kimage *image, void *fdt,
- unsigned long initrd_load_addr, unsigned long initrd_len,
- const char *cmdline)
- {
-- int ret, chosen_node;
-- const void *prop;
--
-- /* Remove memory reservation for the current device tree. */
-- ret = delete_fdt_mem_rsv(fdt, __pa(initial_boot_params),
-- fdt_totalsize(initial_boot_params));
-- if (ret == 0)
-- pr_debug("Removed old device tree reservation.\n");
-- else if (ret != -ENOENT)
-- return ret;
--
-- chosen_node = fdt_path_offset(fdt, "/chosen");
-- if (chosen_node == -FDT_ERR_NOTFOUND) {
-- chosen_node = fdt_add_subnode(fdt, fdt_path_offset(fdt, "/"),
-- "chosen");
-- if (chosen_node < 0) {
-- pr_err("Error creating /chosen.\n");
-- return -EINVAL;
-- }
-- } else if (chosen_node < 0) {
-- pr_err("Malformed device tree: error reading /chosen.\n");
-- return -EINVAL;
-- }
--
-- /* Did we boot using an initrd? */
-- prop = fdt_getprop(fdt, chosen_node, "linux,initrd-start", NULL);
-- if (prop) {
-- uint64_t tmp_start, tmp_end, tmp_size;
--
-- tmp_start = fdt64_to_cpu(*((const fdt64_t *) prop));
--
-- prop = fdt_getprop(fdt, chosen_node, "linux,initrd-end", NULL);
-- if (!prop) {
-- pr_err("Malformed device tree.\n");
-- return -EINVAL;
-- }
-- tmp_end = fdt64_to_cpu(*((const fdt64_t *) prop));
--
-- /*
-- * kexec reserves exact initrd size, while firmware may
-- * reserve a multiple of PAGE_SIZE, so check for both.
-- */
-- tmp_size = tmp_end - tmp_start;
-- ret = delete_fdt_mem_rsv(fdt, tmp_start, tmp_size);
-- if (ret == -ENOENT)
-- ret = delete_fdt_mem_rsv(fdt, tmp_start,
-- round_up(tmp_size, PAGE_SIZE));
-- if (ret == 0)
-- pr_debug("Removed old initrd reservation.\n");
-- else if (ret != -ENOENT)
-- return ret;
--
-- /* If there's no new initrd, delete the old initrd's info. */
-- if (initrd_len == 0) {
-- ret = fdt_delprop(fdt, chosen_node,
-- "linux,initrd-start");
-- if (ret) {
-- pr_err("Error deleting linux,initrd-start.\n");
-- return -EINVAL;
-- }
--
-- ret = fdt_delprop(fdt, chosen_node, "linux,initrd-end");
-- if (ret) {
-- pr_err("Error deleting linux,initrd-end.\n");
-- return -EINVAL;
-- }
-- }
-- }
--
-- if (initrd_len) {
-- ret = fdt_setprop_u64(fdt, chosen_node,
-- "linux,initrd-start",
-- initrd_load_addr);
-- if (ret < 0)
-- goto err;
--
-- /* initrd-end is the first address after the initrd image. */
-- ret = fdt_setprop_u64(fdt, chosen_node, "linux,initrd-end",
-- initrd_load_addr + initrd_len);
-- if (ret < 0)
-- goto err;
--
-- ret = fdt_add_mem_rsv(fdt, initrd_load_addr, initrd_len);
-- if (ret) {
-- pr_err("Error reserving initrd memory: %s\n",
-- fdt_strerror(ret));
-- return -EINVAL;
-- }
-- }
--
-- if (cmdline != NULL) {
-- ret = fdt_setprop_string(fdt, chosen_node, "bootargs", cmdline);
-- if (ret < 0)
-- goto err;
-- } else {
-- ret = fdt_delprop(fdt, chosen_node, "bootargs");
-- if (ret && ret != -FDT_ERR_NOTFOUND) {
-- pr_err("Error deleting bootargs.\n");
-- return -EINVAL;
-- }
-- }
--
-- if (image->type == KEXEC_TYPE_CRASH) {
-- /*
-- * Avoid elfcorehdr from being stomped on in kdump kernel by
-- * setting up memory reserve map.
-- */
-- ret = fdt_add_mem_rsv(fdt, image->arch.elf_load_addr,
-- image->arch.elf_headers_sz);
-- if (ret) {
-- pr_err("Error reserving elfcorehdr memory: %s\n",
-- fdt_strerror(ret));
-- goto err;
-- }
-- }
--
-- ret = setup_ima_buffer(image, fdt, chosen_node);
-- if (ret) {
-- pr_err("Error setting up the new device tree.\n");
-- return ret;
-- }
-+ int ret;
-
-- ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
-+ ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
- if (ret)
-- goto err;
--
-- return 0;
-+ pr_err("Error setting up the new device tree.\n");
-
--err:
-- pr_err("Error setting up the new device tree.\n");
-- return -EINVAL;
-+ return ret;
- }
-diff --git a/arch/powerpc/kexec/file_load_64.c b/arch/powerpc/kexec/file_load_64.c
-index e539b7d401a2..0463ed8ff9ea 100644
---- a/arch/powerpc/kexec/file_load_64.c
-+++ b/arch/powerpc/kexec/file_load_64.c
-@@ -1111,5 +1111,8 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image)
- image->arch.elf_headers = NULL;
- image->arch.elf_headers_sz = 0;
-
-+ kvfree(image->arch.fdt);
-+ image->arch.fdt = NULL;
-+
- return kexec_image_post_load_cleanup_default(image);
- }
+ static inline void of_core_init(void)
--
2.30.0