linux/drivers/of/kexec.c
Linus Torvalds da8d07af4b Devicetree updates for v6.0:
Bindings:
 - Add spi-peripheral-props.yaml references to various SPI device
   bindings
 
 - Convert qcom,pm8916-wdt, ds1307, Qualcomm BAM DMA, is31fl319x,
   skyworks,aat1290, Rockchip EMAC, gpio-ir-receiver, ahci-ceva, Arm CCN
   PMU, rda,8810pl-intc, sil,sii9022, ps2-gpio, and arm-firmware-suite
   bindings to DT schema format
 
 - New bindings for Arm virtual platforms display, Qualcomm IMEM memory
   region, Samsung S5PV210 ChipID, EM Microelectronic EM3027 RTC, and
   arm,cortex-a78ae
 
 - Add vendor prefixes for asrock, bytedance, hxt, ingrasys, inventec,
   quanta, and densitron
 
 - Add missing MSI and IOMMU properties to host-generic-pci
 
 - Remove bindings for removed EFM32 platform
 
 - Remove old chosen.txt binding (replaced by schema)
 
 - Treewide add missing type information for properties
 
 - Treewide fixing of typos and its vs. it's in bindings. Its all good
   now.
 
 - Drop unnecessary quoting in power related schemas
 
 - Several LED binding updates which didn't get picked up
 
 - Move various bindings to proper directories
 
 DT core code:
 - Convert unittest GPIO related tests to use fwnode
 
 - Check ima-kexec-buffer against memory bounds
 
 - Print reserved-memory allocation/reservation failures as errors
 
 - Cleanup early_init_dt_reserve_memory_arch()
 
 - Simplify of_overlay_fdt_apply() tail
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEktVUI4SxYhzZyEuo+vtdtY28YcMFAmLpmdUQHHJvYmhAa2Vy
 bmVsLm9yZwAKCRD6+121jbxhw8RKD/0dWJ6kDoM5IgS+gzklHA4cBgtHoqHa8Aun
 wDMP6bLxFtlGtAExkfO1ZvNgv1movEYwtSkNKKLuzK/Uv65ln693xWMKza0VEQCl
 1/C1+BQUGMrrMxheMvyWyoGTzOuP65Oh74xDutVlOMN5GxUNEtnU6OdX+F1TLNtD
 utL0arf44y8pAC+eouLTl0bDeMi3rnLT7Y/UEuhh59nVVy+Fi04jvV/UjNx0Vp6m
 /jViiCSxPl77zU2nL7kdOE91Peaqb4YgdXjSgvnhXcJ8zDZZgai64u3Kq0k5whM6
 U6HvIpjvzwDJG5qfW7rdM8dFMUECYNWMqlrqhpX1m/FQQejUBalPnklTtqwkrzsj
 8QXJB0y1BMf6lwIjFDHZoxk4sfd3fcSJegkZK+wip9FdpGe+78GBUp2RU+gfMgv9
 lUSLq0mrmjEuazqm+C95okzFbLeZk+WAgAmH2GYaTc1VYa6WrBYnTZIy8ngTe+VS
 ywklQbBUXMaV13A5gKQSNZx9rdyJVgqRcLuRxosxNt5ms411oiKjjj2m6adTUXmR
 jos67YYdSHiKmn7Omj8biOw2lDQe0PMZmhgqNTe7nAWho26v6uV/HgLz6xNPtEDx
 Lj6+xBz96RH0ANWS9O0GLk+GDe7svsXTmj+9GkCFlY3PioMvB3Fmph7p9Hjxkq2P
 8zQFxWGgAg==
 =8/kk
 -----END PGP SIGNATURE-----

Merge tag 'devicetree-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull devicetree updates from Rob Herring:
 "Bindings:

   - Add spi-peripheral-props.yaml references to various SPI device
     bindings

   - Convert qcom,pm8916-wdt, ds1307, Qualcomm BAM DMA, is31fl319x,
     skyworks,aat1290, Rockchip EMAC, gpio-ir-receiver, ahci-ceva, Arm
     CCN PMU, rda,8810pl-intc, sil,sii9022, ps2-gpio, and
     arm-firmware-suite bindings to DT schema format

   - New bindings for Arm virtual platforms display, Qualcomm IMEM
     memory region, Samsung S5PV210 ChipID, EM Microelectronic EM3027
     RTC, and arm,cortex-a78ae

   - Add vendor prefixes for asrock, bytedance, hxt, ingrasys, inventec,
     quanta, and densitron

   - Add missing MSI and IOMMU properties to host-generic-pci

   - Remove bindings for removed EFM32 platform

   - Remove old chosen.txt binding (replaced by schema)

   - Treewide add missing type information for properties

   - Treewide fixing of typos and its vs. it's in bindings. Its all good
     now.

   - Drop unnecessary quoting in power related schemas

   - Several LED binding updates which didn't get picked up

   - Move various bindings to proper directories

  DT core code:

   - Convert unittest GPIO related tests to use fwnode

   - Check ima-kexec-buffer against memory bounds

   - Print reserved-memory allocation/reservation failures as errors

   - Cleanup early_init_dt_reserve_memory_arch()

   - Simplify of_overlay_fdt_apply() tail"

* tag 'devicetree-for-6.0' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (65 commits)
  dt-bindings: mtd: microchip,mchp48l640: use spi-peripheral-props.yaml
  dt-bindings: power: supply: drop quotes when not needed
  dt-bindings: power: reset: drop quotes when not needed
  dt-bindings: power: drop quotes when not needed
  dt-bindings: PCI: host-generic-pci: Allow IOMMU and MSI properties
  of/fdt: declared return type does not match actual return type
  devicetree/bindings: correct possessive "its" typos
  dt-bindings: net: convert emac_rockchip.txt to YAML
  dt-bindings: eeprom: microchip,93lc46b: move to eeprom directory
  dt-bindings: eeprom: at25: use spi-peripheral-props.yaml
  dt-bindings: display: use spi-peripheral-props.yaml
  dt-bindings: watchdog: qcom,pm8916-wdt: convert to dtschema
  dt-bindings: power: reset: qcom,pon: use absolute path to other schema
  dt-bindings: iio/dac: adi,ad5766: Add missing type to 'output-range-microvolts'
  dt-bindings: power: supply: charger-manager: Add missing type for 'cm-battery-stat'
  dt-bindings: panel: raydium,rm67191: Add missing type to 'video-mode'
  of/fdt: Clean up early_init_dt_reserve_memory_arch()
  dt-bindings: PCI: fsl,imx6q-pcie: Add missing type for 'reset-gpio-active-high'
  dt-bindings: rtc: Add EM Microelectronic EM3027 bindings
  dt-bindings: rtc: ds1307: Convert to json-schema
  ...
2022-08-04 18:08:34 -07:00

472 lines
11 KiB
C

// 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/ima.h>
#include <linux/kernel.h>
#include <linux/kexec.h>
#include <linux/memblock.h>
#include <linux/libfdt.h>
#include <linux/of.h>
#include <linux/of_fdt.h>
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/types.h>
#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;
}
/**
* get_addr_size_cells - Get address and size of root node
*
* @addr_cells: Return address of the root node
* @size_cells: Return size of the root node
*
* Return: 0 on success, or negative errno on error.
*/
static int get_addr_size_cells(int *addr_cells, int *size_cells)
{
struct device_node *root;
root = of_find_node_by_path("/");
if (!root)
return -EINVAL;
*addr_cells = of_n_addr_cells(root);
*size_cells = of_n_size_cells(root);
of_node_put(root);
return 0;
}
/**
* do_get_kexec_buffer - Get address and size of device tree property
*
* @prop: Device tree property
* @len: Size of @prop
* @addr: Return address of the node
* @size: Return size of the node
*
* Return: 0 on success, or negative errno on error.
*/
static int do_get_kexec_buffer(const void *prop, int len, unsigned long *addr,
size_t *size)
{
int ret, addr_cells, size_cells;
ret = get_addr_size_cells(&addr_cells, &size_cells);
if (ret)
return ret;
if (len < 4 * (addr_cells + size_cells))
return -ENOENT;
*addr = of_read_number(prop, addr_cells);
*size = of_read_number(prop + 4 * addr_cells, size_cells);
return 0;
}
#ifdef CONFIG_HAVE_IMA_KEXEC
/**
* ima_get_kexec_buffer - get IMA buffer from the previous kernel
* @addr: On successful return, set to point to the buffer contents.
* @size: On successful return, set to the buffer size.
*
* Return: 0 on success, negative errno on error.
*/
int __init ima_get_kexec_buffer(void **addr, size_t *size)
{
int ret, len;
unsigned long tmp_addr;
unsigned long start_pfn, end_pfn;
size_t tmp_size;
const void *prop;
prop = of_get_property(of_chosen, "linux,ima-kexec-buffer", &len);
if (!prop)
return -ENOENT;
ret = do_get_kexec_buffer(prop, len, &tmp_addr, &tmp_size);
if (ret)
return ret;
/* Do some sanity on the returned size for the ima-kexec buffer */
if (!tmp_size)
return -ENOENT;
/*
* Calculate the PFNs for the buffer and ensure
* they are with in addressable memory.
*/
start_pfn = PHYS_PFN(tmp_addr);
end_pfn = PHYS_PFN(tmp_addr + tmp_size - 1);
if (!page_is_ram(start_pfn) || !page_is_ram(end_pfn)) {
pr_warn("IMA buffer at 0x%lx, size = 0x%zx beyond memory\n",
tmp_addr, tmp_size);
return -EINVAL;
}
*addr = __va(tmp_addr);
*size = tmp_size;
return 0;
}
/**
* ima_free_kexec_buffer - free memory used by the IMA buffer
*/
int __init ima_free_kexec_buffer(void)
{
int ret;
unsigned long addr;
size_t size;
struct property *prop;
prop = of_find_property(of_chosen, "linux,ima-kexec-buffer", NULL);
if (!prop)
return -ENOENT;
ret = do_get_kexec_buffer(prop->value, prop->length, &addr, &size);
if (ret)
return ret;
ret = of_remove_property(of_chosen, prop);
if (ret)
return ret;
return memblock_phys_free(addr, size);
}
#endif
/**
* 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.
*/
static void remove_ima_buffer(void *fdt, int chosen_node)
{
int ret, len;
unsigned long addr;
size_t size;
const void *prop;
if (!IS_ENABLED(CONFIG_HAVE_IMA_KEXEC))
return;
prop = fdt_getprop(fdt, chosen_node, "linux,ima-kexec-buffer", &len);
if (!prop)
return;
ret = do_get_kexec_buffer(prop, len, &addr, &size);
fdt_delprop(fdt, chosen_node, "linux,ima-kexec-buffer");
if (ret)
return;
ret = fdt_find_and_del_mem_rsv(fdt, addr, size);
if (!ret)
pr_debug("Removed old IMA buffer reservation.\n");
}
#ifdef CONFIG_IMA_KEXEC
/**
* setup_ima_buffer - add IMA buffer information to the fdt
* @image: kexec image being loaded.
* @fdt: Flattened device tree for the next kernel.
* @chosen_node: Offset to the chosen node.
*
* Return: 0 on success, or negative errno on error.
*/
static int setup_ima_buffer(const struct kimage *image, void *fdt,
int chosen_node)
{
int ret;
if (!image->ima_buffer_size)
return 0;
ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
"linux,ima-kexec-buffer",
image->ima_buffer_addr,
image->ima_buffer_size);
if (ret < 0)
return -EINVAL;
ret = fdt_add_mem_rsv(fdt, image->ima_buffer_addr,
image->ima_buffer_size);
if (ret)
return -EINVAL;
pr_debug("IMA buffer at 0x%llx, size = 0x%zx\n",
image->ima_buffer_addr, image->ima_buffer_size);
return 0;
}
#else /* CONFIG_IMA_KEXEC */
static inline int setup_ima_buffer(const struct kimage *image, void *fdt,
int chosen_node)
{
return 0;
}
#endif /* CONFIG_IMA_KEXEC */
/*
* 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, "linux,elfcorehdr");
if (ret && ret != -FDT_ERR_NOTFOUND)
goto out;
ret = fdt_delprop(fdt, chosen_node, "linux,usable-memory-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, "linux,initrd-start",
initrd_load_addr);
if (ret)
goto out;
ret = fdt_setprop_u64(fdt, chosen_node, "linux,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, "linux,initrd-start");
if (ret && (ret != -FDT_ERR_NOTFOUND))
goto out;
ret = fdt_delprop(fdt, chosen_node, "linux,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,
"linux,elfcorehdr", 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,
"linux,usable-memory-range", crashk_res.start,
crashk_res.end - crashk_res.start + 1);
if (ret)
goto out;
if (crashk_low_res.end) {
ret = fdt_appendprop_addrrange(fdt, 0, chosen_node,
"linux,usable-memory-range",
crashk_low_res.start,
crashk_low_res.end - crashk_low_res.start + 1);
if (ret)
goto out;
}
}
/* add bootargs */
if (cmdline) {
ret = fdt_setprop_string(fdt, chosen_node, "bootargs", cmdline);
if (ret)
goto out;
} else {
ret = fdt_delprop(fdt, chosen_node, "bootargs");
if (ret && (ret != -FDT_ERR_NOTFOUND))
goto out;
}
/* add kaslr-seed */
ret = fdt_delprop(fdt, chosen_node, "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, "kaslr-seed", seed);
if (ret)
goto out;
} else {
pr_notice("RNG is not initialised: omitting \"%s\" property\n",
"kaslr-seed");
}
/* add rng-seed */
if (rng_is_initialized()) {
void *rng_seed;
ret = fdt_setprop_placeholder(fdt, chosen_node, "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",
"rng-seed");
}
ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
if (ret)
goto out;
remove_ima_buffer(fdt, chosen_node);
ret = setup_ima_buffer(image, fdt, fdt_path_offset(fdt, "/chosen"));
out:
if (ret) {
kvfree(fdt);
fdt = NULL;
}
return fdt;
}