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authorLinus Torvalds <torvalds@linux-foundation.org>2019-12-01 01:35:43 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2019-12-01 01:35:43 +0300
commit7794b1d4185e2587af46435e3e2f6696dae314c7 (patch)
tree593973e28050fa09799db0bddf02502e33c3de31 /arch/powerpc/kexec/file_load.c
parent9dd0013824fc29e618db7a5b0bac5545285b946a (diff)
parent2807273f5e88ed086d7d5d838fdee71e11e5085f (diff)
downloadlinux-7794b1d4185e2587af46435e3e2f6696dae314c7.tar.xz
Merge tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman: "Highlights: - Infrastructure for secure boot on some bare metal Power9 machines. The firmware support is still in development, so the code here won't actually activate secure boot on any existing systems. - A change to xmon (our crash handler / pseudo-debugger) to restrict it to read-only mode when the kernel is lockdown'ed, otherwise it's trivial to drop into xmon and modify kernel data, such as the lockdown state. - Support for KASLR on 32-bit BookE machines (Freescale / NXP). - Fixes for our flush_icache_range() and __kernel_sync_dicache() (VDSO) to work with memory ranges >4GB. - Some reworks of the pseries CMM (Cooperative Memory Management) driver to make it behave more like other balloon drivers and enable some cleanups of generic mm code. - A series of fixes to our hardware breakpoint support to properly handle unaligned watchpoint addresses. Plus a bunch of other smaller improvements, fixes and cleanups. Thanks to: Alastair D'Silva, Andrew Donnellan, Aneesh Kumar K.V, Anthony Steinhauser, Cédric Le Goater, Chris Packham, Chris Smart, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens, David Hildenbrand, Deb McLemore, Diana Craciun, Eric Richter, Geert Uytterhoeven, Greg Kroah-Hartman, Greg Kurz, Gustavo L. F. Walbon, Hari Bathini, Harish, Jason Yan, Krzysztof Kozlowski, Leonardo Bras, Mathieu Malaterre, Mauro S. M. Rodrigues, Michal Suchanek, Mimi Zohar, Nathan Chancellor, Nathan Lynch, Nayna Jain, Nick Desaulniers, Oliver O'Halloran, Qian Cai, Rasmus Villemoes, Ravi Bangoria, Sam Bobroff, Santosh Sivaraj, Scott Wood, Thomas Huth, Tyrel Datwyler, Vaibhav Jain, Valentin Longchamp, YueHaibing" * tag 'powerpc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (144 commits) powerpc/fixmap: fix crash with HIGHMEM x86/efi: remove unused variables powerpc: Define arch_is_kernel_initmem_freed() for lockdep powerpc/prom_init: Use -ffreestanding to avoid a reference to bcmp powerpc: Avoid clang warnings around setjmp and longjmp powerpc: Don't add -mabi= flags when building with Clang powerpc: Fix Kconfig indentation powerpc/fixmap: don't clear fixmap area in paging_init() selftests/powerpc: spectre_v2 test must be built 64-bit powerpc/powernv: Disable native PCIe port management powerpc/kexec: Move kexec files into a dedicated subdir. powerpc/32: Split kexec low level code out of misc_32.S powerpc/sysdev: drop simple gpio powerpc/83xx: map IMMR with a BAT. powerpc/32s: automatically allocate BAT in setbat() powerpc/ioremap: warn on early use of ioremap() powerpc: Add support for GENERIC_EARLY_IOREMAP powerpc/fixmap: Use __fix_to_virt() instead of fix_to_virt() powerpc/8xx: use the fixmapped IMMR in cpm_reset() powerpc/8xx: add __init to cpm1 init functions ...
Diffstat (limited to 'arch/powerpc/kexec/file_load.c')
-rw-r--r--arch/powerpc/kexec/file_load.c254
1 files changed, 254 insertions, 0 deletions
diff --git a/arch/powerpc/kexec/file_load.c b/arch/powerpc/kexec/file_load.c
new file mode 100644
index 000000000000..143c91724617
--- /dev/null
+++ b/arch/powerpc/kexec/file_load.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ppc64 code to implement the kexec_file_load syscall
+ *
+ * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
+ * Copyright (C) 2004 IBM Corp.
+ * Copyright (C) 2004,2005 Milton D Miller II, IBM Corporation
+ * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
+ * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
+ * Copyright (C) 2016 IBM Corporation
+ *
+ * Based on kexec-tools' kexec-elf-ppc64.c, fs2dt.c.
+ * Heavily modified for the kernel by
+ * Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>.
+ */
+
+#include <linux/slab.h>
+#include <linux/kexec.h>
+#include <linux/of_fdt.h>
+#include <linux/libfdt.h>
+#include <asm/ima.h>
+
+#define SLAVE_CODE_SIZE 256
+
+const struct kexec_file_ops * const kexec_file_loaders[] = {
+ &kexec_elf64_ops,
+ NULL
+};
+
+int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
+ unsigned long buf_len)
+{
+ /* We don't support crash kernels yet. */
+ if (image->type == KEXEC_TYPE_CRASH)
+ return -EOPNOTSUPP;
+
+ return kexec_image_probe_default(image, buf, buf_len);
+}
+
+/**
+ * setup_purgatory - initialize the purgatory's global variables
+ * @image: kexec image.
+ * @slave_code: Slave code for the purgatory.
+ * @fdt: Flattened device tree for the next kernel.
+ * @kernel_load_addr: Address where the kernel is loaded.
+ * @fdt_load_addr: Address where the flattened device tree is loaded.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int setup_purgatory(struct kimage *image, const void *slave_code,
+ const void *fdt, unsigned long kernel_load_addr,
+ unsigned long fdt_load_addr)
+{
+ unsigned int *slave_code_buf, master_entry;
+ int ret;
+
+ slave_code_buf = kmalloc(SLAVE_CODE_SIZE, GFP_KERNEL);
+ if (!slave_code_buf)
+ return -ENOMEM;
+
+ /* Get the slave code from the new kernel and put it in purgatory. */
+ ret = kexec_purgatory_get_set_symbol(image, "purgatory_start",
+ slave_code_buf, SLAVE_CODE_SIZE,
+ true);
+ if (ret) {
+ kfree(slave_code_buf);
+ return ret;
+ }
+
+ master_entry = slave_code_buf[0];
+ memcpy(slave_code_buf, slave_code, SLAVE_CODE_SIZE);
+ slave_code_buf[0] = master_entry;
+ ret = kexec_purgatory_get_set_symbol(image, "purgatory_start",
+ slave_code_buf, SLAVE_CODE_SIZE,
+ false);
+ kfree(slave_code_buf);
+
+ ret = kexec_purgatory_get_set_symbol(image, "kernel", &kernel_load_addr,
+ sizeof(kernel_load_addr), false);
+ if (ret)
+ return ret;
+ ret = kexec_purgatory_get_set_symbol(image, "dt_offset", &fdt_load_addr,
+ sizeof(fdt_load_addr), false);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+/**
+ * delete_fdt_mem_rsv - delete memory reservation with given address and size
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+int delete_fdt_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++) {
+ uint64_t 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;
+}
+
+/*
+ * setup_new_fdt - modify /chosen and memory reservation for the next kernel
+ * @image: kexec image being loaded.
+ * @fdt: Flattened device tree for the next kernel.
+ * @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.
+ *
+ * Return: 0 on success, or negative errno on error.
+ */
+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;
+ }
+ }
+
+ ret = setup_ima_buffer(image, fdt, chosen_node);
+ if (ret) {
+ pr_err("Error setting up the new device tree.\n");
+ return ret;
+ }
+
+ ret = fdt_setprop(fdt, chosen_node, "linux,booted-from-kexec", NULL, 0);
+ if (ret)
+ goto err;
+
+ return 0;
+
+err:
+ pr_err("Error setting up the new device tree.\n");
+ return -EINVAL;
+}