--- v10
+++ v19
@@ -1,131 +1,338 @@
-remove_ima_buffer() removes the chosen node "linux,ima-kexec-buffer"
-from the device tree and frees the memory reserved for carrying forward
-the IMA measurement logs on kexec. This function does not have
-architecture specific code, but is currently limited to powerpc.
-
-Move remove_ima_buffer() to "drivers/of/ima_kexec.c" so that it is
-accessible for other architectures as well.
-
-Co-developed-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
-Signed-off-by: Prakhar Srivastava <prsriva@linux.microsoft.com>
+From: Rob Herring <robh@kernel.org>
+
+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/ima.h | 8 ++------
- arch/powerpc/kexec/ima.c | 26 --------------------------
- drivers/of/kexec.c | 29 +++++++++++++++++++++++++++++
- include/linux/kexec.h | 1 +
- 4 files changed, 32 insertions(+), 32 deletions(-)
-
-diff --git a/arch/powerpc/include/asm/ima.h b/arch/powerpc/include/asm/ima.h
-index ead488cf3981..a2fc71bc3b23 100644
---- a/arch/powerpc/include/asm/ima.h
-+++ b/arch/powerpc/include/asm/ima.h
-@@ -2,17 +2,13 @@
- #ifndef _ASM_POWERPC_IMA_H
- #define _ASM_POWERPC_IMA_H
+ 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>
-+
- struct kimage;
++#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,
- int ima_get_kexec_buffer(void **addr, size_t *size);
- int ima_free_kexec_buffer(void);
+ phys_addr_t of_dma_get_max_cpu_address(struct device_node *np);
--#ifdef CONFIG_IMA
--void remove_ima_buffer(void *fdt, int chosen_node);
--#else
--static inline void remove_ima_buffer(void *fdt, int chosen_node) {}
--#endif
--
- #ifdef CONFIG_IMA_KEXEC
- int arch_ima_add_kexec_buffer(struct kimage *image, unsigned long load_addr,
- size_t size);
-diff --git a/arch/powerpc/kexec/ima.c b/arch/powerpc/kexec/ima.c
-index 906e8212435d..68017123b07d 100644
---- a/arch/powerpc/kexec/ima.c
-+++ b/arch/powerpc/kexec/ima.c
-@@ -61,32 +61,6 @@ int ima_free_kexec_buffer(void)
- return memblock_free(addr, size);
- }
++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 */
--/**
-- * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
-- *
-- * @fdt: Flattened Device Tree to update
-- * @chosen_node: Offset to the chosen node in the device tree
-- *
-- * The IMA measurement buffer is of no use to a subsequent kernel, so we always
-- * remove it from the device tree.
-- */
--void remove_ima_buffer(void *fdt, int chosen_node)
--{
-- int ret;
-- unsigned long addr;
-- size_t size;
--
-- ret = get_ima_kexec_buffer(fdt, chosen_node, &addr, &size);
-- if (ret)
-- return;
--
-- fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
--
-- ret = delete_fdt_mem_rsv(fdt, addr, size);
-- if (!ret)
-- pr_debug("Removed old IMA buffer reservation.\n");
--}
--
- #ifdef CONFIG_IMA_KEXEC
- /**
- * arch_ima_add_kexec_buffer - do arch-specific steps to add the IMA buffer
-diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c
-index 516b86f7113a..42d16dfff78d 100644
---- a/drivers/of/kexec.c
-+++ b/drivers/of/kexec.c
-@@ -129,3 +129,32 @@ int get_ima_kexec_buffer(void *fdt, int chosen_node,
-
- return 0;
- }
-+
-+/**
-+ * remove_ima_buffer - remove the IMA buffer property and reservation from @fdt
-+ *
-+ * @fdt: Flattened Device Tree to update
-+ * @chosen_node: Offset to the chosen node in the device tree
-+ *
-+ * The IMA measurement buffer is of no use to a subsequent kernel, so we always
-+ * remove it from the device tree.
-+ */
-+void remove_ima_buffer(void *fdt, int chosen_node)
-+{
-+ int ret;
-+ unsigned long addr;
-+ size_t size;
-+
-+ if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
-+ return;
-+
-+ ret = get_ima_kexec_buffer(fdt, chosen_node, &addr, &size);
-+ if (ret)
-+ return;
-+
-+ fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
-+
-+ ret = delete_fdt_mem_rsv(fdt, addr, size);
-+ if (!ret)
-+ pr_debug("Removed old IMA buffer reservation.\n");
-+}
-diff --git a/include/linux/kexec.h b/include/linux/kexec.h
-index 10ff704ab670..52a0efff184d 100644
---- a/include/linux/kexec.h
-+++ b/include/linux/kexec.h
-@@ -411,6 +411,7 @@ static inline int kexec_crash_loaded(void) { return 0; }
- extern int get_root_addr_size_cells(int *addr_cells, int *size_cells);
- extern int get_ima_kexec_buffer(void *fdt, int chosen_node,
- unsigned long *addr, size_t *size);
-+extern void remove_ima_buffer(void *fdt, int chosen_node);
- extern int delete_fdt_mem_rsv(void *fdt, unsigned long start,
- unsigned long size);
- #endif /* CONFIG_OF_FLATTREE */
+ static inline void of_core_init(void)
--
-2.29.2
-
+2.30.0
+