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![Martin Schwidefsky](/assets/img/avatar_default.png)
Introduce KEXEC_CONTROL_MEMORY_GFP to allow the architecture code to override the gfp flags of the allocation for the kexec control page. The loop in kimage_alloc_normal_control_pages allocates pages with GFP_KERNEL until a page is found that happens to have an address smaller than the KEXEC_CONTROL_MEMORY_LIMIT. On systems with a large memory size but a small KEXEC_CONTROL_MEMORY_LIMIT the loop will keep allocating memory until the oom killer steps in. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2769 lines
68 KiB
C
2769 lines
68 KiB
C
/*
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* kexec.c - kexec system call
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* Copyright (C) 2002-2004 Eric Biederman <ebiederm@xmission.com>
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*
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* This source code is licensed under the GNU General Public License,
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* Version 2. See the file COPYING for more details.
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*/
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#define pr_fmt(fmt) "kexec: " fmt
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#include <linux/capability.h>
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#include <linux/mm.h>
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#include <linux/file.h>
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#include <linux/slab.h>
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#include <linux/fs.h>
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#include <linux/kexec.h>
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#include <linux/mutex.h>
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#include <linux/list.h>
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#include <linux/highmem.h>
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#include <linux/syscalls.h>
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#include <linux/reboot.h>
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#include <linux/ioport.h>
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#include <linux/hardirq.h>
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#include <linux/elf.h>
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#include <linux/elfcore.h>
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#include <linux/utsname.h>
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#include <linux/numa.h>
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#include <linux/suspend.h>
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#include <linux/device.h>
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#include <linux/freezer.h>
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#include <linux/pm.h>
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#include <linux/cpu.h>
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#include <linux/console.h>
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#include <linux/vmalloc.h>
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#include <linux/swap.h>
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#include <linux/syscore_ops.h>
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#include <linux/compiler.h>
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#include <linux/hugetlb.h>
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#include <asm/page.h>
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#include <asm/uaccess.h>
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#include <asm/io.h>
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#include <asm/sections.h>
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#include <crypto/hash.h>
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#include <crypto/sha.h>
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/* Per cpu memory for storing cpu states in case of system crash. */
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note_buf_t __percpu *crash_notes;
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/* vmcoreinfo stuff */
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static unsigned char vmcoreinfo_data[VMCOREINFO_BYTES];
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u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
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size_t vmcoreinfo_size;
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size_t vmcoreinfo_max_size = sizeof(vmcoreinfo_data);
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/* Flag to indicate we are going to kexec a new kernel */
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bool kexec_in_progress = false;
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/*
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* Declare these symbols weak so that if architecture provides a purgatory,
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* these will be overridden.
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*/
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char __weak kexec_purgatory[0];
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size_t __weak kexec_purgatory_size = 0;
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#ifdef CONFIG_KEXEC_FILE
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static int kexec_calculate_store_digests(struct kimage *image);
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#endif
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/* Location of the reserved area for the crash kernel */
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struct resource crashk_res = {
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.name = "Crash kernel",
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.start = 0,
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.end = 0,
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.flags = IORESOURCE_BUSY | IORESOURCE_MEM
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};
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struct resource crashk_low_res = {
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.name = "Crash kernel",
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.start = 0,
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.end = 0,
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.flags = IORESOURCE_BUSY | IORESOURCE_MEM
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};
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int kexec_should_crash(struct task_struct *p)
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{
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if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops)
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return 1;
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return 0;
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}
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/*
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* When kexec transitions to the new kernel there is a one-to-one
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* mapping between physical and virtual addresses. On processors
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* where you can disable the MMU this is trivial, and easy. For
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* others it is still a simple predictable page table to setup.
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*
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* In that environment kexec copies the new kernel to its final
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* resting place. This means I can only support memory whose
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* physical address can fit in an unsigned long. In particular
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* addresses where (pfn << PAGE_SHIFT) > ULONG_MAX cannot be handled.
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* If the assembly stub has more restrictive requirements
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* KEXEC_SOURCE_MEMORY_LIMIT and KEXEC_DEST_MEMORY_LIMIT can be
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* defined more restrictively in <asm/kexec.h>.
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*
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* The code for the transition from the current kernel to the
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* the new kernel is placed in the control_code_buffer, whose size
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* is given by KEXEC_CONTROL_PAGE_SIZE. In the best case only a single
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* page of memory is necessary, but some architectures require more.
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* Because this memory must be identity mapped in the transition from
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* virtual to physical addresses it must live in the range
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* 0 - TASK_SIZE, as only the user space mappings are arbitrarily
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* modifiable.
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*
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* The assembly stub in the control code buffer is passed a linked list
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* of descriptor pages detailing the source pages of the new kernel,
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* and the destination addresses of those source pages. As this data
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* structure is not used in the context of the current OS, it must
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* be self-contained.
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*
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* The code has been made to work with highmem pages and will use a
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* destination page in its final resting place (if it happens
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* to allocate it). The end product of this is that most of the
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* physical address space, and most of RAM can be used.
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*
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* Future directions include:
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* - allocating a page table with the control code buffer identity
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* mapped, to simplify machine_kexec and make kexec_on_panic more
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* reliable.
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*/
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/*
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* KIMAGE_NO_DEST is an impossible destination address..., for
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* allocating pages whose destination address we do not care about.
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*/
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#define KIMAGE_NO_DEST (-1UL)
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static int kimage_is_destination_range(struct kimage *image,
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unsigned long start, unsigned long end);
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static struct page *kimage_alloc_page(struct kimage *image,
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gfp_t gfp_mask,
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unsigned long dest);
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static int copy_user_segment_list(struct kimage *image,
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unsigned long nr_segments,
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struct kexec_segment __user *segments)
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{
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int ret;
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size_t segment_bytes;
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/* Read in the segments */
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image->nr_segments = nr_segments;
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segment_bytes = nr_segments * sizeof(*segments);
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ret = copy_from_user(image->segment, segments, segment_bytes);
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if (ret)
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ret = -EFAULT;
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return ret;
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}
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static int sanity_check_segment_list(struct kimage *image)
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{
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int result, i;
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unsigned long nr_segments = image->nr_segments;
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/*
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* Verify we have good destination addresses. The caller is
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* responsible for making certain we don't attempt to load
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* the new image into invalid or reserved areas of RAM. This
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* just verifies it is an address we can use.
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*
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* Since the kernel does everything in page size chunks ensure
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* the destination addresses are page aligned. Too many
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* special cases crop of when we don't do this. The most
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* insidious is getting overlapping destination addresses
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* simply because addresses are changed to page size
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* granularity.
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*/
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result = -EADDRNOTAVAIL;
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for (i = 0; i < nr_segments; i++) {
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unsigned long mstart, mend;
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mstart = image->segment[i].mem;
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mend = mstart + image->segment[i].memsz;
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if ((mstart & ~PAGE_MASK) || (mend & ~PAGE_MASK))
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return result;
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if (mend >= KEXEC_DESTINATION_MEMORY_LIMIT)
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return result;
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}
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/* Verify our destination addresses do not overlap.
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* If we alloed overlapping destination addresses
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* through very weird things can happen with no
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* easy explanation as one segment stops on another.
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*/
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result = -EINVAL;
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for (i = 0; i < nr_segments; i++) {
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unsigned long mstart, mend;
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unsigned long j;
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mstart = image->segment[i].mem;
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mend = mstart + image->segment[i].memsz;
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for (j = 0; j < i; j++) {
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unsigned long pstart, pend;
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pstart = image->segment[j].mem;
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pend = pstart + image->segment[j].memsz;
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/* Do the segments overlap ? */
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if ((mend > pstart) && (mstart < pend))
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return result;
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}
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}
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/* Ensure our buffer sizes are strictly less than
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* our memory sizes. This should always be the case,
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* and it is easier to check up front than to be surprised
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* later on.
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*/
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result = -EINVAL;
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for (i = 0; i < nr_segments; i++) {
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if (image->segment[i].bufsz > image->segment[i].memsz)
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return result;
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}
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/*
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* Verify we have good destination addresses. Normally
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* the caller is responsible for making certain we don't
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* attempt to load the new image into invalid or reserved
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* areas of RAM. But crash kernels are preloaded into a
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* reserved area of ram. We must ensure the addresses
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* are in the reserved area otherwise preloading the
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* kernel could corrupt things.
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*/
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if (image->type == KEXEC_TYPE_CRASH) {
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result = -EADDRNOTAVAIL;
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for (i = 0; i < nr_segments; i++) {
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unsigned long mstart, mend;
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mstart = image->segment[i].mem;
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mend = mstart + image->segment[i].memsz - 1;
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/* Ensure we are within the crash kernel limits */
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if ((mstart < crashk_res.start) ||
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(mend > crashk_res.end))
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return result;
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}
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}
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return 0;
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}
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static struct kimage *do_kimage_alloc_init(void)
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{
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struct kimage *image;
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/* Allocate a controlling structure */
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image = kzalloc(sizeof(*image), GFP_KERNEL);
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if (!image)
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return NULL;
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image->head = 0;
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image->entry = &image->head;
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image->last_entry = &image->head;
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image->control_page = ~0; /* By default this does not apply */
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image->type = KEXEC_TYPE_DEFAULT;
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/* Initialize the list of control pages */
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INIT_LIST_HEAD(&image->control_pages);
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/* Initialize the list of destination pages */
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INIT_LIST_HEAD(&image->dest_pages);
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/* Initialize the list of unusable pages */
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INIT_LIST_HEAD(&image->unusable_pages);
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return image;
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}
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static void kimage_free_page_list(struct list_head *list);
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static int kimage_alloc_init(struct kimage **rimage, unsigned long entry,
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unsigned long nr_segments,
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struct kexec_segment __user *segments,
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unsigned long flags)
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{
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int ret;
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struct kimage *image;
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bool kexec_on_panic = flags & KEXEC_ON_CRASH;
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if (kexec_on_panic) {
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/* Verify we have a valid entry point */
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if ((entry < crashk_res.start) || (entry > crashk_res.end))
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return -EADDRNOTAVAIL;
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}
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/* Allocate and initialize a controlling structure */
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image = do_kimage_alloc_init();
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if (!image)
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return -ENOMEM;
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image->start = entry;
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ret = copy_user_segment_list(image, nr_segments, segments);
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if (ret)
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goto out_free_image;
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ret = sanity_check_segment_list(image);
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if (ret)
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goto out_free_image;
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/* Enable the special crash kernel control page allocation policy. */
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if (kexec_on_panic) {
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image->control_page = crashk_res.start;
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image->type = KEXEC_TYPE_CRASH;
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}
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/*
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* Find a location for the control code buffer, and add it
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* the vector of segments so that it's pages will also be
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* counted as destination pages.
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*/
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ret = -ENOMEM;
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image->control_code_page = kimage_alloc_control_pages(image,
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get_order(KEXEC_CONTROL_PAGE_SIZE));
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if (!image->control_code_page) {
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pr_err("Could not allocate control_code_buffer\n");
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goto out_free_image;
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}
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if (!kexec_on_panic) {
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image->swap_page = kimage_alloc_control_pages(image, 0);
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if (!image->swap_page) {
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pr_err("Could not allocate swap buffer\n");
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goto out_free_control_pages;
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}
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}
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*rimage = image;
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return 0;
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out_free_control_pages:
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kimage_free_page_list(&image->control_pages);
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out_free_image:
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kfree(image);
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return ret;
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}
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#ifdef CONFIG_KEXEC_FILE
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static int copy_file_from_fd(int fd, void **buf, unsigned long *buf_len)
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{
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struct fd f = fdget(fd);
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int ret;
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struct kstat stat;
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loff_t pos;
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ssize_t bytes = 0;
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if (!f.file)
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return -EBADF;
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ret = vfs_getattr(&f.file->f_path, &stat);
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if (ret)
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goto out;
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if (stat.size > INT_MAX) {
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ret = -EFBIG;
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|
goto out;
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|
}
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|
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/* Don't hand 0 to vmalloc, it whines. */
|
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if (stat.size == 0) {
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ret = -EINVAL;
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goto out;
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}
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*buf = vmalloc(stat.size);
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if (!*buf) {
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ret = -ENOMEM;
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goto out;
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}
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pos = 0;
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while (pos < stat.size) {
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bytes = kernel_read(f.file, pos, (char *)(*buf) + pos,
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stat.size - pos);
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if (bytes < 0) {
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vfree(*buf);
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ret = bytes;
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goto out;
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}
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|
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if (bytes == 0)
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break;
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pos += bytes;
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}
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|
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if (pos != stat.size) {
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ret = -EBADF;
|
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vfree(*buf);
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goto out;
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}
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|
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*buf_len = pos;
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out:
|
|
fdput(f);
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return ret;
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}
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|
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/* Architectures can provide this probe function */
|
|
int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
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unsigned long buf_len)
|
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{
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return -ENOEXEC;
|
|
}
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|
|
|
void * __weak arch_kexec_kernel_image_load(struct kimage *image)
|
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{
|
|
return ERR_PTR(-ENOEXEC);
|
|
}
|
|
|
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void __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
|
|
{
|
|
}
|
|
|
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int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
|
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unsigned long buf_len)
|
|
{
|
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return -EKEYREJECTED;
|
|
}
|
|
|
|
/* Apply relocations of type RELA */
|
|
int __weak
|
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arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
|
|
unsigned int relsec)
|
|
{
|
|
pr_err("RELA relocation unsupported.\n");
|
|
return -ENOEXEC;
|
|
}
|
|
|
|
/* Apply relocations of type REL */
|
|
int __weak
|
|
arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
|
|
unsigned int relsec)
|
|
{
|
|
pr_err("REL relocation unsupported.\n");
|
|
return -ENOEXEC;
|
|
}
|
|
|
|
/*
|
|
* Free up memory used by kernel, initrd, and command line. This is temporary
|
|
* memory allocation which is not needed any more after these buffers have
|
|
* been loaded into separate segments and have been copied elsewhere.
|
|
*/
|
|
static void kimage_file_post_load_cleanup(struct kimage *image)
|
|
{
|
|
struct purgatory_info *pi = &image->purgatory_info;
|
|
|
|
vfree(image->kernel_buf);
|
|
image->kernel_buf = NULL;
|
|
|
|
vfree(image->initrd_buf);
|
|
image->initrd_buf = NULL;
|
|
|
|
kfree(image->cmdline_buf);
|
|
image->cmdline_buf = NULL;
|
|
|
|
vfree(pi->purgatory_buf);
|
|
pi->purgatory_buf = NULL;
|
|
|
|
vfree(pi->sechdrs);
|
|
pi->sechdrs = NULL;
|
|
|
|
/* See if architecture has anything to cleanup post load */
|
|
arch_kimage_file_post_load_cleanup(image);
|
|
|
|
/*
|
|
* Above call should have called into bootloader to free up
|
|
* any data stored in kimage->image_loader_data. It should
|
|
* be ok now to free it up.
|
|
*/
|
|
kfree(image->image_loader_data);
|
|
image->image_loader_data = NULL;
|
|
}
|
|
|
|
/*
|
|
* In file mode list of segments is prepared by kernel. Copy relevant
|
|
* data from user space, do error checking, prepare segment list
|
|
*/
|
|
static int
|
|
kimage_file_prepare_segments(struct kimage *image, int kernel_fd, int initrd_fd,
|
|
const char __user *cmdline_ptr,
|
|
unsigned long cmdline_len, unsigned flags)
|
|
{
|
|
int ret = 0;
|
|
void *ldata;
|
|
|
|
ret = copy_file_from_fd(kernel_fd, &image->kernel_buf,
|
|
&image->kernel_buf_len);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/* Call arch image probe handlers */
|
|
ret = arch_kexec_kernel_image_probe(image, image->kernel_buf,
|
|
image->kernel_buf_len);
|
|
|
|
if (ret)
|
|
goto out;
|
|
|
|
#ifdef CONFIG_KEXEC_VERIFY_SIG
|
|
ret = arch_kexec_kernel_verify_sig(image, image->kernel_buf,
|
|
image->kernel_buf_len);
|
|
if (ret) {
|
|
pr_debug("kernel signature verification failed.\n");
|
|
goto out;
|
|
}
|
|
pr_debug("kernel signature verification successful.\n");
|
|
#endif
|
|
/* It is possible that there no initramfs is being loaded */
|
|
if (!(flags & KEXEC_FILE_NO_INITRAMFS)) {
|
|
ret = copy_file_from_fd(initrd_fd, &image->initrd_buf,
|
|
&image->initrd_buf_len);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
if (cmdline_len) {
|
|
image->cmdline_buf = kzalloc(cmdline_len, GFP_KERNEL);
|
|
if (!image->cmdline_buf) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
ret = copy_from_user(image->cmdline_buf, cmdline_ptr,
|
|
cmdline_len);
|
|
if (ret) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
image->cmdline_buf_len = cmdline_len;
|
|
|
|
/* command line should be a string with last byte null */
|
|
if (image->cmdline_buf[cmdline_len - 1] != '\0') {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
/* Call arch image load handlers */
|
|
ldata = arch_kexec_kernel_image_load(image);
|
|
|
|
if (IS_ERR(ldata)) {
|
|
ret = PTR_ERR(ldata);
|
|
goto out;
|
|
}
|
|
|
|
image->image_loader_data = ldata;
|
|
out:
|
|
/* In case of error, free up all allocated memory in this function */
|
|
if (ret)
|
|
kimage_file_post_load_cleanup(image);
|
|
return ret;
|
|
}
|
|
|
|
static int
|
|
kimage_file_alloc_init(struct kimage **rimage, int kernel_fd,
|
|
int initrd_fd, const char __user *cmdline_ptr,
|
|
unsigned long cmdline_len, unsigned long flags)
|
|
{
|
|
int ret;
|
|
struct kimage *image;
|
|
bool kexec_on_panic = flags & KEXEC_FILE_ON_CRASH;
|
|
|
|
image = do_kimage_alloc_init();
|
|
if (!image)
|
|
return -ENOMEM;
|
|
|
|
image->file_mode = 1;
|
|
|
|
if (kexec_on_panic) {
|
|
/* Enable special crash kernel control page alloc policy. */
|
|
image->control_page = crashk_res.start;
|
|
image->type = KEXEC_TYPE_CRASH;
|
|
}
|
|
|
|
ret = kimage_file_prepare_segments(image, kernel_fd, initrd_fd,
|
|
cmdline_ptr, cmdline_len, flags);
|
|
if (ret)
|
|
goto out_free_image;
|
|
|
|
ret = sanity_check_segment_list(image);
|
|
if (ret)
|
|
goto out_free_post_load_bufs;
|
|
|
|
ret = -ENOMEM;
|
|
image->control_code_page = kimage_alloc_control_pages(image,
|
|
get_order(KEXEC_CONTROL_PAGE_SIZE));
|
|
if (!image->control_code_page) {
|
|
pr_err("Could not allocate control_code_buffer\n");
|
|
goto out_free_post_load_bufs;
|
|
}
|
|
|
|
if (!kexec_on_panic) {
|
|
image->swap_page = kimage_alloc_control_pages(image, 0);
|
|
if (!image->swap_page) {
|
|
pr_err("Could not allocate swap buffer\n");
|
|
goto out_free_control_pages;
|
|
}
|
|
}
|
|
|
|
*rimage = image;
|
|
return 0;
|
|
out_free_control_pages:
|
|
kimage_free_page_list(&image->control_pages);
|
|
out_free_post_load_bufs:
|
|
kimage_file_post_load_cleanup(image);
|
|
out_free_image:
|
|
kfree(image);
|
|
return ret;
|
|
}
|
|
#else /* CONFIG_KEXEC_FILE */
|
|
static inline void kimage_file_post_load_cleanup(struct kimage *image) { }
|
|
#endif /* CONFIG_KEXEC_FILE */
|
|
|
|
static int kimage_is_destination_range(struct kimage *image,
|
|
unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
unsigned long i;
|
|
|
|
for (i = 0; i < image->nr_segments; i++) {
|
|
unsigned long mstart, mend;
|
|
|
|
mstart = image->segment[i].mem;
|
|
mend = mstart + image->segment[i].memsz;
|
|
if ((end > mstart) && (start < mend))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct page *kimage_alloc_pages(gfp_t gfp_mask, unsigned int order)
|
|
{
|
|
struct page *pages;
|
|
|
|
pages = alloc_pages(gfp_mask, order);
|
|
if (pages) {
|
|
unsigned int count, i;
|
|
pages->mapping = NULL;
|
|
set_page_private(pages, order);
|
|
count = 1 << order;
|
|
for (i = 0; i < count; i++)
|
|
SetPageReserved(pages + i);
|
|
}
|
|
|
|
return pages;
|
|
}
|
|
|
|
static void kimage_free_pages(struct page *page)
|
|
{
|
|
unsigned int order, count, i;
|
|
|
|
order = page_private(page);
|
|
count = 1 << order;
|
|
for (i = 0; i < count; i++)
|
|
ClearPageReserved(page + i);
|
|
__free_pages(page, order);
|
|
}
|
|
|
|
static void kimage_free_page_list(struct list_head *list)
|
|
{
|
|
struct list_head *pos, *next;
|
|
|
|
list_for_each_safe(pos, next, list) {
|
|
struct page *page;
|
|
|
|
page = list_entry(pos, struct page, lru);
|
|
list_del(&page->lru);
|
|
kimage_free_pages(page);
|
|
}
|
|
}
|
|
|
|
static struct page *kimage_alloc_normal_control_pages(struct kimage *image,
|
|
unsigned int order)
|
|
{
|
|
/* Control pages are special, they are the intermediaries
|
|
* that are needed while we copy the rest of the pages
|
|
* to their final resting place. As such they must
|
|
* not conflict with either the destination addresses
|
|
* or memory the kernel is already using.
|
|
*
|
|
* The only case where we really need more than one of
|
|
* these are for architectures where we cannot disable
|
|
* the MMU and must instead generate an identity mapped
|
|
* page table for all of the memory.
|
|
*
|
|
* At worst this runs in O(N) of the image size.
|
|
*/
|
|
struct list_head extra_pages;
|
|
struct page *pages;
|
|
unsigned int count;
|
|
|
|
count = 1 << order;
|
|
INIT_LIST_HEAD(&extra_pages);
|
|
|
|
/* Loop while I can allocate a page and the page allocated
|
|
* is a destination page.
|
|
*/
|
|
do {
|
|
unsigned long pfn, epfn, addr, eaddr;
|
|
|
|
pages = kimage_alloc_pages(KEXEC_CONTROL_MEMORY_GFP, order);
|
|
if (!pages)
|
|
break;
|
|
pfn = page_to_pfn(pages);
|
|
epfn = pfn + count;
|
|
addr = pfn << PAGE_SHIFT;
|
|
eaddr = epfn << PAGE_SHIFT;
|
|
if ((epfn >= (KEXEC_CONTROL_MEMORY_LIMIT >> PAGE_SHIFT)) ||
|
|
kimage_is_destination_range(image, addr, eaddr)) {
|
|
list_add(&pages->lru, &extra_pages);
|
|
pages = NULL;
|
|
}
|
|
} while (!pages);
|
|
|
|
if (pages) {
|
|
/* Remember the allocated page... */
|
|
list_add(&pages->lru, &image->control_pages);
|
|
|
|
/* Because the page is already in it's destination
|
|
* location we will never allocate another page at
|
|
* that address. Therefore kimage_alloc_pages
|
|
* will not return it (again) and we don't need
|
|
* to give it an entry in image->segment[].
|
|
*/
|
|
}
|
|
/* Deal with the destination pages I have inadvertently allocated.
|
|
*
|
|
* Ideally I would convert multi-page allocations into single
|
|
* page allocations, and add everything to image->dest_pages.
|
|
*
|
|
* For now it is simpler to just free the pages.
|
|
*/
|
|
kimage_free_page_list(&extra_pages);
|
|
|
|
return pages;
|
|
}
|
|
|
|
static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
|
|
unsigned int order)
|
|
{
|
|
/* Control pages are special, they are the intermediaries
|
|
* that are needed while we copy the rest of the pages
|
|
* to their final resting place. As such they must
|
|
* not conflict with either the destination addresses
|
|
* or memory the kernel is already using.
|
|
*
|
|
* Control pages are also the only pags we must allocate
|
|
* when loading a crash kernel. All of the other pages
|
|
* are specified by the segments and we just memcpy
|
|
* into them directly.
|
|
*
|
|
* The only case where we really need more than one of
|
|
* these are for architectures where we cannot disable
|
|
* the MMU and must instead generate an identity mapped
|
|
* page table for all of the memory.
|
|
*
|
|
* Given the low demand this implements a very simple
|
|
* allocator that finds the first hole of the appropriate
|
|
* size in the reserved memory region, and allocates all
|
|
* of the memory up to and including the hole.
|
|
*/
|
|
unsigned long hole_start, hole_end, size;
|
|
struct page *pages;
|
|
|
|
pages = NULL;
|
|
size = (1 << order) << PAGE_SHIFT;
|
|
hole_start = (image->control_page + (size - 1)) & ~(size - 1);
|
|
hole_end = hole_start + size - 1;
|
|
while (hole_end <= crashk_res.end) {
|
|
unsigned long i;
|
|
|
|
if (hole_end > KEXEC_CRASH_CONTROL_MEMORY_LIMIT)
|
|
break;
|
|
/* See if I overlap any of the segments */
|
|
for (i = 0; i < image->nr_segments; i++) {
|
|
unsigned long mstart, mend;
|
|
|
|
mstart = image->segment[i].mem;
|
|
mend = mstart + image->segment[i].memsz - 1;
|
|
if ((hole_end >= mstart) && (hole_start <= mend)) {
|
|
/* Advance the hole to the end of the segment */
|
|
hole_start = (mend + (size - 1)) & ~(size - 1);
|
|
hole_end = hole_start + size - 1;
|
|
break;
|
|
}
|
|
}
|
|
/* If I don't overlap any segments I have found my hole! */
|
|
if (i == image->nr_segments) {
|
|
pages = pfn_to_page(hole_start >> PAGE_SHIFT);
|
|
break;
|
|
}
|
|
}
|
|
if (pages)
|
|
image->control_page = hole_end;
|
|
|
|
return pages;
|
|
}
|
|
|
|
|
|
struct page *kimage_alloc_control_pages(struct kimage *image,
|
|
unsigned int order)
|
|
{
|
|
struct page *pages = NULL;
|
|
|
|
switch (image->type) {
|
|
case KEXEC_TYPE_DEFAULT:
|
|
pages = kimage_alloc_normal_control_pages(image, order);
|
|
break;
|
|
case KEXEC_TYPE_CRASH:
|
|
pages = kimage_alloc_crash_control_pages(image, order);
|
|
break;
|
|
}
|
|
|
|
return pages;
|
|
}
|
|
|
|
static int kimage_add_entry(struct kimage *image, kimage_entry_t entry)
|
|
{
|
|
if (*image->entry != 0)
|
|
image->entry++;
|
|
|
|
if (image->entry == image->last_entry) {
|
|
kimage_entry_t *ind_page;
|
|
struct page *page;
|
|
|
|
page = kimage_alloc_page(image, GFP_KERNEL, KIMAGE_NO_DEST);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
|
|
ind_page = page_address(page);
|
|
*image->entry = virt_to_phys(ind_page) | IND_INDIRECTION;
|
|
image->entry = ind_page;
|
|
image->last_entry = ind_page +
|
|
((PAGE_SIZE/sizeof(kimage_entry_t)) - 1);
|
|
}
|
|
*image->entry = entry;
|
|
image->entry++;
|
|
*image->entry = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kimage_set_destination(struct kimage *image,
|
|
unsigned long destination)
|
|
{
|
|
int result;
|
|
|
|
destination &= PAGE_MASK;
|
|
result = kimage_add_entry(image, destination | IND_DESTINATION);
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
static int kimage_add_page(struct kimage *image, unsigned long page)
|
|
{
|
|
int result;
|
|
|
|
page &= PAGE_MASK;
|
|
result = kimage_add_entry(image, page | IND_SOURCE);
|
|
|
|
return result;
|
|
}
|
|
|
|
|
|
static void kimage_free_extra_pages(struct kimage *image)
|
|
{
|
|
/* Walk through and free any extra destination pages I may have */
|
|
kimage_free_page_list(&image->dest_pages);
|
|
|
|
/* Walk through and free any unusable pages I have cached */
|
|
kimage_free_page_list(&image->unusable_pages);
|
|
|
|
}
|
|
static void kimage_terminate(struct kimage *image)
|
|
{
|
|
if (*image->entry != 0)
|
|
image->entry++;
|
|
|
|
*image->entry = IND_DONE;
|
|
}
|
|
|
|
#define for_each_kimage_entry(image, ptr, entry) \
|
|
for (ptr = &image->head; (entry = *ptr) && !(entry & IND_DONE); \
|
|
ptr = (entry & IND_INDIRECTION) ? \
|
|
phys_to_virt((entry & PAGE_MASK)) : ptr + 1)
|
|
|
|
static void kimage_free_entry(kimage_entry_t entry)
|
|
{
|
|
struct page *page;
|
|
|
|
page = pfn_to_page(entry >> PAGE_SHIFT);
|
|
kimage_free_pages(page);
|
|
}
|
|
|
|
static void kimage_free(struct kimage *image)
|
|
{
|
|
kimage_entry_t *ptr, entry;
|
|
kimage_entry_t ind = 0;
|
|
|
|
if (!image)
|
|
return;
|
|
|
|
kimage_free_extra_pages(image);
|
|
for_each_kimage_entry(image, ptr, entry) {
|
|
if (entry & IND_INDIRECTION) {
|
|
/* Free the previous indirection page */
|
|
if (ind & IND_INDIRECTION)
|
|
kimage_free_entry(ind);
|
|
/* Save this indirection page until we are
|
|
* done with it.
|
|
*/
|
|
ind = entry;
|
|
} else if (entry & IND_SOURCE)
|
|
kimage_free_entry(entry);
|
|
}
|
|
/* Free the final indirection page */
|
|
if (ind & IND_INDIRECTION)
|
|
kimage_free_entry(ind);
|
|
|
|
/* Handle any machine specific cleanup */
|
|
machine_kexec_cleanup(image);
|
|
|
|
/* Free the kexec control pages... */
|
|
kimage_free_page_list(&image->control_pages);
|
|
|
|
/*
|
|
* Free up any temporary buffers allocated. This might hit if
|
|
* error occurred much later after buffer allocation.
|
|
*/
|
|
if (image->file_mode)
|
|
kimage_file_post_load_cleanup(image);
|
|
|
|
kfree(image);
|
|
}
|
|
|
|
static kimage_entry_t *kimage_dst_used(struct kimage *image,
|
|
unsigned long page)
|
|
{
|
|
kimage_entry_t *ptr, entry;
|
|
unsigned long destination = 0;
|
|
|
|
for_each_kimage_entry(image, ptr, entry) {
|
|
if (entry & IND_DESTINATION)
|
|
destination = entry & PAGE_MASK;
|
|
else if (entry & IND_SOURCE) {
|
|
if (page == destination)
|
|
return ptr;
|
|
destination += PAGE_SIZE;
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static struct page *kimage_alloc_page(struct kimage *image,
|
|
gfp_t gfp_mask,
|
|
unsigned long destination)
|
|
{
|
|
/*
|
|
* Here we implement safeguards to ensure that a source page
|
|
* is not copied to its destination page before the data on
|
|
* the destination page is no longer useful.
|
|
*
|
|
* To do this we maintain the invariant that a source page is
|
|
* either its own destination page, or it is not a
|
|
* destination page at all.
|
|
*
|
|
* That is slightly stronger than required, but the proof
|
|
* that no problems will not occur is trivial, and the
|
|
* implementation is simply to verify.
|
|
*
|
|
* When allocating all pages normally this algorithm will run
|
|
* in O(N) time, but in the worst case it will run in O(N^2)
|
|
* time. If the runtime is a problem the data structures can
|
|
* be fixed.
|
|
*/
|
|
struct page *page;
|
|
unsigned long addr;
|
|
|
|
/*
|
|
* Walk through the list of destination pages, and see if I
|
|
* have a match.
|
|
*/
|
|
list_for_each_entry(page, &image->dest_pages, lru) {
|
|
addr = page_to_pfn(page) << PAGE_SHIFT;
|
|
if (addr == destination) {
|
|
list_del(&page->lru);
|
|
return page;
|
|
}
|
|
}
|
|
page = NULL;
|
|
while (1) {
|
|
kimage_entry_t *old;
|
|
|
|
/* Allocate a page, if we run out of memory give up */
|
|
page = kimage_alloc_pages(gfp_mask, 0);
|
|
if (!page)
|
|
return NULL;
|
|
/* If the page cannot be used file it away */
|
|
if (page_to_pfn(page) >
|
|
(KEXEC_SOURCE_MEMORY_LIMIT >> PAGE_SHIFT)) {
|
|
list_add(&page->lru, &image->unusable_pages);
|
|
continue;
|
|
}
|
|
addr = page_to_pfn(page) << PAGE_SHIFT;
|
|
|
|
/* If it is the destination page we want use it */
|
|
if (addr == destination)
|
|
break;
|
|
|
|
/* If the page is not a destination page use it */
|
|
if (!kimage_is_destination_range(image, addr,
|
|
addr + PAGE_SIZE))
|
|
break;
|
|
|
|
/*
|
|
* I know that the page is someones destination page.
|
|
* See if there is already a source page for this
|
|
* destination page. And if so swap the source pages.
|
|
*/
|
|
old = kimage_dst_used(image, addr);
|
|
if (old) {
|
|
/* If so move it */
|
|
unsigned long old_addr;
|
|
struct page *old_page;
|
|
|
|
old_addr = *old & PAGE_MASK;
|
|
old_page = pfn_to_page(old_addr >> PAGE_SHIFT);
|
|
copy_highpage(page, old_page);
|
|
*old = addr | (*old & ~PAGE_MASK);
|
|
|
|
/* The old page I have found cannot be a
|
|
* destination page, so return it if it's
|
|
* gfp_flags honor the ones passed in.
|
|
*/
|
|
if (!(gfp_mask & __GFP_HIGHMEM) &&
|
|
PageHighMem(old_page)) {
|
|
kimage_free_pages(old_page);
|
|
continue;
|
|
}
|
|
addr = old_addr;
|
|
page = old_page;
|
|
break;
|
|
} else {
|
|
/* Place the page on the destination list I
|
|
* will use it later.
|
|
*/
|
|
list_add(&page->lru, &image->dest_pages);
|
|
}
|
|
}
|
|
|
|
return page;
|
|
}
|
|
|
|
static int kimage_load_normal_segment(struct kimage *image,
|
|
struct kexec_segment *segment)
|
|
{
|
|
unsigned long maddr;
|
|
size_t ubytes, mbytes;
|
|
int result;
|
|
unsigned char __user *buf = NULL;
|
|
unsigned char *kbuf = NULL;
|
|
|
|
result = 0;
|
|
if (image->file_mode)
|
|
kbuf = segment->kbuf;
|
|
else
|
|
buf = segment->buf;
|
|
ubytes = segment->bufsz;
|
|
mbytes = segment->memsz;
|
|
maddr = segment->mem;
|
|
|
|
result = kimage_set_destination(image, maddr);
|
|
if (result < 0)
|
|
goto out;
|
|
|
|
while (mbytes) {
|
|
struct page *page;
|
|
char *ptr;
|
|
size_t uchunk, mchunk;
|
|
|
|
page = kimage_alloc_page(image, GFP_HIGHUSER, maddr);
|
|
if (!page) {
|
|
result = -ENOMEM;
|
|
goto out;
|
|
}
|
|
result = kimage_add_page(image, page_to_pfn(page)
|
|
<< PAGE_SHIFT);
|
|
if (result < 0)
|
|
goto out;
|
|
|
|
ptr = kmap(page);
|
|
/* Start with a clear page */
|
|
clear_page(ptr);
|
|
ptr += maddr & ~PAGE_MASK;
|
|
mchunk = min_t(size_t, mbytes,
|
|
PAGE_SIZE - (maddr & ~PAGE_MASK));
|
|
uchunk = min(ubytes, mchunk);
|
|
|
|
/* For file based kexec, source pages are in kernel memory */
|
|
if (image->file_mode)
|
|
memcpy(ptr, kbuf, uchunk);
|
|
else
|
|
result = copy_from_user(ptr, buf, uchunk);
|
|
kunmap(page);
|
|
if (result) {
|
|
result = -EFAULT;
|
|
goto out;
|
|
}
|
|
ubytes -= uchunk;
|
|
maddr += mchunk;
|
|
if (image->file_mode)
|
|
kbuf += mchunk;
|
|
else
|
|
buf += mchunk;
|
|
mbytes -= mchunk;
|
|
}
|
|
out:
|
|
return result;
|
|
}
|
|
|
|
static int kimage_load_crash_segment(struct kimage *image,
|
|
struct kexec_segment *segment)
|
|
{
|
|
/* For crash dumps kernels we simply copy the data from
|
|
* user space to it's destination.
|
|
* We do things a page at a time for the sake of kmap.
|
|
*/
|
|
unsigned long maddr;
|
|
size_t ubytes, mbytes;
|
|
int result;
|
|
unsigned char __user *buf = NULL;
|
|
unsigned char *kbuf = NULL;
|
|
|
|
result = 0;
|
|
if (image->file_mode)
|
|
kbuf = segment->kbuf;
|
|
else
|
|
buf = segment->buf;
|
|
ubytes = segment->bufsz;
|
|
mbytes = segment->memsz;
|
|
maddr = segment->mem;
|
|
while (mbytes) {
|
|
struct page *page;
|
|
char *ptr;
|
|
size_t uchunk, mchunk;
|
|
|
|
page = pfn_to_page(maddr >> PAGE_SHIFT);
|
|
if (!page) {
|
|
result = -ENOMEM;
|
|
goto out;
|
|
}
|
|
ptr = kmap(page);
|
|
ptr += maddr & ~PAGE_MASK;
|
|
mchunk = min_t(size_t, mbytes,
|
|
PAGE_SIZE - (maddr & ~PAGE_MASK));
|
|
uchunk = min(ubytes, mchunk);
|
|
if (mchunk > uchunk) {
|
|
/* Zero the trailing part of the page */
|
|
memset(ptr + uchunk, 0, mchunk - uchunk);
|
|
}
|
|
|
|
/* For file based kexec, source pages are in kernel memory */
|
|
if (image->file_mode)
|
|
memcpy(ptr, kbuf, uchunk);
|
|
else
|
|
result = copy_from_user(ptr, buf, uchunk);
|
|
kexec_flush_icache_page(page);
|
|
kunmap(page);
|
|
if (result) {
|
|
result = -EFAULT;
|
|
goto out;
|
|
}
|
|
ubytes -= uchunk;
|
|
maddr += mchunk;
|
|
if (image->file_mode)
|
|
kbuf += mchunk;
|
|
else
|
|
buf += mchunk;
|
|
mbytes -= mchunk;
|
|
}
|
|
out:
|
|
return result;
|
|
}
|
|
|
|
static int kimage_load_segment(struct kimage *image,
|
|
struct kexec_segment *segment)
|
|
{
|
|
int result = -ENOMEM;
|
|
|
|
switch (image->type) {
|
|
case KEXEC_TYPE_DEFAULT:
|
|
result = kimage_load_normal_segment(image, segment);
|
|
break;
|
|
case KEXEC_TYPE_CRASH:
|
|
result = kimage_load_crash_segment(image, segment);
|
|
break;
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Exec Kernel system call: for obvious reasons only root may call it.
|
|
*
|
|
* This call breaks up into three pieces.
|
|
* - A generic part which loads the new kernel from the current
|
|
* address space, and very carefully places the data in the
|
|
* allocated pages.
|
|
*
|
|
* - A generic part that interacts with the kernel and tells all of
|
|
* the devices to shut down. Preventing on-going dmas, and placing
|
|
* the devices in a consistent state so a later kernel can
|
|
* reinitialize them.
|
|
*
|
|
* - A machine specific part that includes the syscall number
|
|
* and then copies the image to it's final destination. And
|
|
* jumps into the image at entry.
|
|
*
|
|
* kexec does not sync, or unmount filesystems so if you need
|
|
* that to happen you need to do that yourself.
|
|
*/
|
|
struct kimage *kexec_image;
|
|
struct kimage *kexec_crash_image;
|
|
int kexec_load_disabled;
|
|
|
|
static DEFINE_MUTEX(kexec_mutex);
|
|
|
|
SYSCALL_DEFINE4(kexec_load, unsigned long, entry, unsigned long, nr_segments,
|
|
struct kexec_segment __user *, segments, unsigned long, flags)
|
|
{
|
|
struct kimage **dest_image, *image;
|
|
int result;
|
|
|
|
/* We only trust the superuser with rebooting the system. */
|
|
if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
|
|
return -EPERM;
|
|
|
|
/*
|
|
* Verify we have a legal set of flags
|
|
* This leaves us room for future extensions.
|
|
*/
|
|
if ((flags & KEXEC_FLAGS) != (flags & ~KEXEC_ARCH_MASK))
|
|
return -EINVAL;
|
|
|
|
/* Verify we are on the appropriate architecture */
|
|
if (((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH) &&
|
|
((flags & KEXEC_ARCH_MASK) != KEXEC_ARCH_DEFAULT))
|
|
return -EINVAL;
|
|
|
|
/* Put an artificial cap on the number
|
|
* of segments passed to kexec_load.
|
|
*/
|
|
if (nr_segments > KEXEC_SEGMENT_MAX)
|
|
return -EINVAL;
|
|
|
|
image = NULL;
|
|
result = 0;
|
|
|
|
/* Because we write directly to the reserved memory
|
|
* region when loading crash kernels we need a mutex here to
|
|
* prevent multiple crash kernels from attempting to load
|
|
* simultaneously, and to prevent a crash kernel from loading
|
|
* over the top of a in use crash kernel.
|
|
*
|
|
* KISS: always take the mutex.
|
|
*/
|
|
if (!mutex_trylock(&kexec_mutex))
|
|
return -EBUSY;
|
|
|
|
dest_image = &kexec_image;
|
|
if (flags & KEXEC_ON_CRASH)
|
|
dest_image = &kexec_crash_image;
|
|
if (nr_segments > 0) {
|
|
unsigned long i;
|
|
|
|
if (flags & KEXEC_ON_CRASH) {
|
|
/*
|
|
* Loading another kernel to switch to if this one
|
|
* crashes. Free any current crash dump kernel before
|
|
* we corrupt it.
|
|
*/
|
|
|
|
kimage_free(xchg(&kexec_crash_image, NULL));
|
|
result = kimage_alloc_init(&image, entry, nr_segments,
|
|
segments, flags);
|
|
crash_map_reserved_pages();
|
|
} else {
|
|
/* Loading another kernel to reboot into. */
|
|
|
|
result = kimage_alloc_init(&image, entry, nr_segments,
|
|
segments, flags);
|
|
}
|
|
if (result)
|
|
goto out;
|
|
|
|
if (flags & KEXEC_PRESERVE_CONTEXT)
|
|
image->preserve_context = 1;
|
|
result = machine_kexec_prepare(image);
|
|
if (result)
|
|
goto out;
|
|
|
|
for (i = 0; i < nr_segments; i++) {
|
|
result = kimage_load_segment(image, &image->segment[i]);
|
|
if (result)
|
|
goto out;
|
|
}
|
|
kimage_terminate(image);
|
|
if (flags & KEXEC_ON_CRASH)
|
|
crash_unmap_reserved_pages();
|
|
}
|
|
/* Install the new kernel, and Uninstall the old */
|
|
image = xchg(dest_image, image);
|
|
|
|
out:
|
|
mutex_unlock(&kexec_mutex);
|
|
kimage_free(image);
|
|
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Add and remove page tables for crashkernel memory
|
|
*
|
|
* Provide an empty default implementation here -- architecture
|
|
* code may override this
|
|
*/
|
|
void __weak crash_map_reserved_pages(void)
|
|
{}
|
|
|
|
void __weak crash_unmap_reserved_pages(void)
|
|
{}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
COMPAT_SYSCALL_DEFINE4(kexec_load, compat_ulong_t, entry,
|
|
compat_ulong_t, nr_segments,
|
|
struct compat_kexec_segment __user *, segments,
|
|
compat_ulong_t, flags)
|
|
{
|
|
struct compat_kexec_segment in;
|
|
struct kexec_segment out, __user *ksegments;
|
|
unsigned long i, result;
|
|
|
|
/* Don't allow clients that don't understand the native
|
|
* architecture to do anything.
|
|
*/
|
|
if ((flags & KEXEC_ARCH_MASK) == KEXEC_ARCH_DEFAULT)
|
|
return -EINVAL;
|
|
|
|
if (nr_segments > KEXEC_SEGMENT_MAX)
|
|
return -EINVAL;
|
|
|
|
ksegments = compat_alloc_user_space(nr_segments * sizeof(out));
|
|
for (i = 0; i < nr_segments; i++) {
|
|
result = copy_from_user(&in, &segments[i], sizeof(in));
|
|
if (result)
|
|
return -EFAULT;
|
|
|
|
out.buf = compat_ptr(in.buf);
|
|
out.bufsz = in.bufsz;
|
|
out.mem = in.mem;
|
|
out.memsz = in.memsz;
|
|
|
|
result = copy_to_user(&ksegments[i], &out, sizeof(out));
|
|
if (result)
|
|
return -EFAULT;
|
|
}
|
|
|
|
return sys_kexec_load(entry, nr_segments, ksegments, flags);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_KEXEC_FILE
|
|
SYSCALL_DEFINE5(kexec_file_load, int, kernel_fd, int, initrd_fd,
|
|
unsigned long, cmdline_len, const char __user *, cmdline_ptr,
|
|
unsigned long, flags)
|
|
{
|
|
int ret = 0, i;
|
|
struct kimage **dest_image, *image;
|
|
|
|
/* We only trust the superuser with rebooting the system. */
|
|
if (!capable(CAP_SYS_BOOT) || kexec_load_disabled)
|
|
return -EPERM;
|
|
|
|
/* Make sure we have a legal set of flags */
|
|
if (flags != (flags & KEXEC_FILE_FLAGS))
|
|
return -EINVAL;
|
|
|
|
image = NULL;
|
|
|
|
if (!mutex_trylock(&kexec_mutex))
|
|
return -EBUSY;
|
|
|
|
dest_image = &kexec_image;
|
|
if (flags & KEXEC_FILE_ON_CRASH)
|
|
dest_image = &kexec_crash_image;
|
|
|
|
if (flags & KEXEC_FILE_UNLOAD)
|
|
goto exchange;
|
|
|
|
/*
|
|
* In case of crash, new kernel gets loaded in reserved region. It is
|
|
* same memory where old crash kernel might be loaded. Free any
|
|
* current crash dump kernel before we corrupt it.
|
|
*/
|
|
if (flags & KEXEC_FILE_ON_CRASH)
|
|
kimage_free(xchg(&kexec_crash_image, NULL));
|
|
|
|
ret = kimage_file_alloc_init(&image, kernel_fd, initrd_fd, cmdline_ptr,
|
|
cmdline_len, flags);
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = machine_kexec_prepare(image);
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = kexec_calculate_store_digests(image);
|
|
if (ret)
|
|
goto out;
|
|
|
|
for (i = 0; i < image->nr_segments; i++) {
|
|
struct kexec_segment *ksegment;
|
|
|
|
ksegment = &image->segment[i];
|
|
pr_debug("Loading segment %d: buf=0x%p bufsz=0x%zx mem=0x%lx memsz=0x%zx\n",
|
|
i, ksegment->buf, ksegment->bufsz, ksegment->mem,
|
|
ksegment->memsz);
|
|
|
|
ret = kimage_load_segment(image, &image->segment[i]);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
kimage_terminate(image);
|
|
|
|
/*
|
|
* Free up any temporary buffers allocated which are not needed
|
|
* after image has been loaded
|
|
*/
|
|
kimage_file_post_load_cleanup(image);
|
|
exchange:
|
|
image = xchg(dest_image, image);
|
|
out:
|
|
mutex_unlock(&kexec_mutex);
|
|
kimage_free(image);
|
|
return ret;
|
|
}
|
|
|
|
#endif /* CONFIG_KEXEC_FILE */
|
|
|
|
void crash_kexec(struct pt_regs *regs)
|
|
{
|
|
/* Take the kexec_mutex here to prevent sys_kexec_load
|
|
* running on one cpu from replacing the crash kernel
|
|
* we are using after a panic on a different cpu.
|
|
*
|
|
* If the crash kernel was not located in a fixed area
|
|
* of memory the xchg(&kexec_crash_image) would be
|
|
* sufficient. But since I reuse the memory...
|
|
*/
|
|
if (mutex_trylock(&kexec_mutex)) {
|
|
if (kexec_crash_image) {
|
|
struct pt_regs fixed_regs;
|
|
|
|
crash_setup_regs(&fixed_regs, regs);
|
|
crash_save_vmcoreinfo();
|
|
machine_crash_shutdown(&fixed_regs);
|
|
machine_kexec(kexec_crash_image);
|
|
}
|
|
mutex_unlock(&kexec_mutex);
|
|
}
|
|
}
|
|
|
|
size_t crash_get_memory_size(void)
|
|
{
|
|
size_t size = 0;
|
|
mutex_lock(&kexec_mutex);
|
|
if (crashk_res.end != crashk_res.start)
|
|
size = resource_size(&crashk_res);
|
|
mutex_unlock(&kexec_mutex);
|
|
return size;
|
|
}
|
|
|
|
void __weak crash_free_reserved_phys_range(unsigned long begin,
|
|
unsigned long end)
|
|
{
|
|
unsigned long addr;
|
|
|
|
for (addr = begin; addr < end; addr += PAGE_SIZE)
|
|
free_reserved_page(pfn_to_page(addr >> PAGE_SHIFT));
|
|
}
|
|
|
|
int crash_shrink_memory(unsigned long new_size)
|
|
{
|
|
int ret = 0;
|
|
unsigned long start, end;
|
|
unsigned long old_size;
|
|
struct resource *ram_res;
|
|
|
|
mutex_lock(&kexec_mutex);
|
|
|
|
if (kexec_crash_image) {
|
|
ret = -ENOENT;
|
|
goto unlock;
|
|
}
|
|
start = crashk_res.start;
|
|
end = crashk_res.end;
|
|
old_size = (end == 0) ? 0 : end - start + 1;
|
|
if (new_size >= old_size) {
|
|
ret = (new_size == old_size) ? 0 : -EINVAL;
|
|
goto unlock;
|
|
}
|
|
|
|
ram_res = kzalloc(sizeof(*ram_res), GFP_KERNEL);
|
|
if (!ram_res) {
|
|
ret = -ENOMEM;
|
|
goto unlock;
|
|
}
|
|
|
|
start = roundup(start, KEXEC_CRASH_MEM_ALIGN);
|
|
end = roundup(start + new_size, KEXEC_CRASH_MEM_ALIGN);
|
|
|
|
crash_map_reserved_pages();
|
|
crash_free_reserved_phys_range(end, crashk_res.end);
|
|
|
|
if ((start == end) && (crashk_res.parent != NULL))
|
|
release_resource(&crashk_res);
|
|
|
|
ram_res->start = end;
|
|
ram_res->end = crashk_res.end;
|
|
ram_res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
|
|
ram_res->name = "System RAM";
|
|
|
|
crashk_res.end = end - 1;
|
|
|
|
insert_resource(&iomem_resource, ram_res);
|
|
crash_unmap_reserved_pages();
|
|
|
|
unlock:
|
|
mutex_unlock(&kexec_mutex);
|
|
return ret;
|
|
}
|
|
|
|
static u32 *append_elf_note(u32 *buf, char *name, unsigned type, void *data,
|
|
size_t data_len)
|
|
{
|
|
struct elf_note note;
|
|
|
|
note.n_namesz = strlen(name) + 1;
|
|
note.n_descsz = data_len;
|
|
note.n_type = type;
|
|
memcpy(buf, ¬e, sizeof(note));
|
|
buf += (sizeof(note) + 3)/4;
|
|
memcpy(buf, name, note.n_namesz);
|
|
buf += (note.n_namesz + 3)/4;
|
|
memcpy(buf, data, note.n_descsz);
|
|
buf += (note.n_descsz + 3)/4;
|
|
|
|
return buf;
|
|
}
|
|
|
|
static void final_note(u32 *buf)
|
|
{
|
|
struct elf_note note;
|
|
|
|
note.n_namesz = 0;
|
|
note.n_descsz = 0;
|
|
note.n_type = 0;
|
|
memcpy(buf, ¬e, sizeof(note));
|
|
}
|
|
|
|
void crash_save_cpu(struct pt_regs *regs, int cpu)
|
|
{
|
|
struct elf_prstatus prstatus;
|
|
u32 *buf;
|
|
|
|
if ((cpu < 0) || (cpu >= nr_cpu_ids))
|
|
return;
|
|
|
|
/* Using ELF notes here is opportunistic.
|
|
* I need a well defined structure format
|
|
* for the data I pass, and I need tags
|
|
* on the data to indicate what information I have
|
|
* squirrelled away. ELF notes happen to provide
|
|
* all of that, so there is no need to invent something new.
|
|
*/
|
|
buf = (u32 *)per_cpu_ptr(crash_notes, cpu);
|
|
if (!buf)
|
|
return;
|
|
memset(&prstatus, 0, sizeof(prstatus));
|
|
prstatus.pr_pid = current->pid;
|
|
elf_core_copy_kernel_regs(&prstatus.pr_reg, regs);
|
|
buf = append_elf_note(buf, KEXEC_CORE_NOTE_NAME, NT_PRSTATUS,
|
|
&prstatus, sizeof(prstatus));
|
|
final_note(buf);
|
|
}
|
|
|
|
static int __init crash_notes_memory_init(void)
|
|
{
|
|
/* Allocate memory for saving cpu registers. */
|
|
crash_notes = alloc_percpu(note_buf_t);
|
|
if (!crash_notes) {
|
|
pr_warn("Kexec: Memory allocation for saving cpu register states failed\n");
|
|
return -ENOMEM;
|
|
}
|
|
return 0;
|
|
}
|
|
subsys_initcall(crash_notes_memory_init);
|
|
|
|
|
|
/*
|
|
* parsing the "crashkernel" commandline
|
|
*
|
|
* this code is intended to be called from architecture specific code
|
|
*/
|
|
|
|
|
|
/*
|
|
* This function parses command lines in the format
|
|
*
|
|
* crashkernel=ramsize-range:size[,...][@offset]
|
|
*
|
|
* The function returns 0 on success and -EINVAL on failure.
|
|
*/
|
|
static int __init parse_crashkernel_mem(char *cmdline,
|
|
unsigned long long system_ram,
|
|
unsigned long long *crash_size,
|
|
unsigned long long *crash_base)
|
|
{
|
|
char *cur = cmdline, *tmp;
|
|
|
|
/* for each entry of the comma-separated list */
|
|
do {
|
|
unsigned long long start, end = ULLONG_MAX, size;
|
|
|
|
/* get the start of the range */
|
|
start = memparse(cur, &tmp);
|
|
if (cur == tmp) {
|
|
pr_warn("crashkernel: Memory value expected\n");
|
|
return -EINVAL;
|
|
}
|
|
cur = tmp;
|
|
if (*cur != '-') {
|
|
pr_warn("crashkernel: '-' expected\n");
|
|
return -EINVAL;
|
|
}
|
|
cur++;
|
|
|
|
/* if no ':' is here, than we read the end */
|
|
if (*cur != ':') {
|
|
end = memparse(cur, &tmp);
|
|
if (cur == tmp) {
|
|
pr_warn("crashkernel: Memory value expected\n");
|
|
return -EINVAL;
|
|
}
|
|
cur = tmp;
|
|
if (end <= start) {
|
|
pr_warn("crashkernel: end <= start\n");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
if (*cur != ':') {
|
|
pr_warn("crashkernel: ':' expected\n");
|
|
return -EINVAL;
|
|
}
|
|
cur++;
|
|
|
|
size = memparse(cur, &tmp);
|
|
if (cur == tmp) {
|
|
pr_warn("Memory value expected\n");
|
|
return -EINVAL;
|
|
}
|
|
cur = tmp;
|
|
if (size >= system_ram) {
|
|
pr_warn("crashkernel: invalid size\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* match ? */
|
|
if (system_ram >= start && system_ram < end) {
|
|
*crash_size = size;
|
|
break;
|
|
}
|
|
} while (*cur++ == ',');
|
|
|
|
if (*crash_size > 0) {
|
|
while (*cur && *cur != ' ' && *cur != '@')
|
|
cur++;
|
|
if (*cur == '@') {
|
|
cur++;
|
|
*crash_base = memparse(cur, &tmp);
|
|
if (cur == tmp) {
|
|
pr_warn("Memory value expected after '@'\n");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* That function parses "simple" (old) crashkernel command lines like
|
|
*
|
|
* crashkernel=size[@offset]
|
|
*
|
|
* It returns 0 on success and -EINVAL on failure.
|
|
*/
|
|
static int __init parse_crashkernel_simple(char *cmdline,
|
|
unsigned long long *crash_size,
|
|
unsigned long long *crash_base)
|
|
{
|
|
char *cur = cmdline;
|
|
|
|
*crash_size = memparse(cmdline, &cur);
|
|
if (cmdline == cur) {
|
|
pr_warn("crashkernel: memory value expected\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (*cur == '@')
|
|
*crash_base = memparse(cur+1, &cur);
|
|
else if (*cur != ' ' && *cur != '\0') {
|
|
pr_warn("crashkernel: unrecognized char\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#define SUFFIX_HIGH 0
|
|
#define SUFFIX_LOW 1
|
|
#define SUFFIX_NULL 2
|
|
static __initdata char *suffix_tbl[] = {
|
|
[SUFFIX_HIGH] = ",high",
|
|
[SUFFIX_LOW] = ",low",
|
|
[SUFFIX_NULL] = NULL,
|
|
};
|
|
|
|
/*
|
|
* That function parses "suffix" crashkernel command lines like
|
|
*
|
|
* crashkernel=size,[high|low]
|
|
*
|
|
* It returns 0 on success and -EINVAL on failure.
|
|
*/
|
|
static int __init parse_crashkernel_suffix(char *cmdline,
|
|
unsigned long long *crash_size,
|
|
const char *suffix)
|
|
{
|
|
char *cur = cmdline;
|
|
|
|
*crash_size = memparse(cmdline, &cur);
|
|
if (cmdline == cur) {
|
|
pr_warn("crashkernel: memory value expected\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* check with suffix */
|
|
if (strncmp(cur, suffix, strlen(suffix))) {
|
|
pr_warn("crashkernel: unrecognized char\n");
|
|
return -EINVAL;
|
|
}
|
|
cur += strlen(suffix);
|
|
if (*cur != ' ' && *cur != '\0') {
|
|
pr_warn("crashkernel: unrecognized char\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static __init char *get_last_crashkernel(char *cmdline,
|
|
const char *name,
|
|
const char *suffix)
|
|
{
|
|
char *p = cmdline, *ck_cmdline = NULL;
|
|
|
|
/* find crashkernel and use the last one if there are more */
|
|
p = strstr(p, name);
|
|
while (p) {
|
|
char *end_p = strchr(p, ' ');
|
|
char *q;
|
|
|
|
if (!end_p)
|
|
end_p = p + strlen(p);
|
|
|
|
if (!suffix) {
|
|
int i;
|
|
|
|
/* skip the one with any known suffix */
|
|
for (i = 0; suffix_tbl[i]; i++) {
|
|
q = end_p - strlen(suffix_tbl[i]);
|
|
if (!strncmp(q, suffix_tbl[i],
|
|
strlen(suffix_tbl[i])))
|
|
goto next;
|
|
}
|
|
ck_cmdline = p;
|
|
} else {
|
|
q = end_p - strlen(suffix);
|
|
if (!strncmp(q, suffix, strlen(suffix)))
|
|
ck_cmdline = p;
|
|
}
|
|
next:
|
|
p = strstr(p+1, name);
|
|
}
|
|
|
|
if (!ck_cmdline)
|
|
return NULL;
|
|
|
|
return ck_cmdline;
|
|
}
|
|
|
|
static int __init __parse_crashkernel(char *cmdline,
|
|
unsigned long long system_ram,
|
|
unsigned long long *crash_size,
|
|
unsigned long long *crash_base,
|
|
const char *name,
|
|
const char *suffix)
|
|
{
|
|
char *first_colon, *first_space;
|
|
char *ck_cmdline;
|
|
|
|
BUG_ON(!crash_size || !crash_base);
|
|
*crash_size = 0;
|
|
*crash_base = 0;
|
|
|
|
ck_cmdline = get_last_crashkernel(cmdline, name, suffix);
|
|
|
|
if (!ck_cmdline)
|
|
return -EINVAL;
|
|
|
|
ck_cmdline += strlen(name);
|
|
|
|
if (suffix)
|
|
return parse_crashkernel_suffix(ck_cmdline, crash_size,
|
|
suffix);
|
|
/*
|
|
* if the commandline contains a ':', then that's the extended
|
|
* syntax -- if not, it must be the classic syntax
|
|
*/
|
|
first_colon = strchr(ck_cmdline, ':');
|
|
first_space = strchr(ck_cmdline, ' ');
|
|
if (first_colon && (!first_space || first_colon < first_space))
|
|
return parse_crashkernel_mem(ck_cmdline, system_ram,
|
|
crash_size, crash_base);
|
|
|
|
return parse_crashkernel_simple(ck_cmdline, crash_size, crash_base);
|
|
}
|
|
|
|
/*
|
|
* That function is the entry point for command line parsing and should be
|
|
* called from the arch-specific code.
|
|
*/
|
|
int __init parse_crashkernel(char *cmdline,
|
|
unsigned long long system_ram,
|
|
unsigned long long *crash_size,
|
|
unsigned long long *crash_base)
|
|
{
|
|
return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
|
|
"crashkernel=", NULL);
|
|
}
|
|
|
|
int __init parse_crashkernel_high(char *cmdline,
|
|
unsigned long long system_ram,
|
|
unsigned long long *crash_size,
|
|
unsigned long long *crash_base)
|
|
{
|
|
return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
|
|
"crashkernel=", suffix_tbl[SUFFIX_HIGH]);
|
|
}
|
|
|
|
int __init parse_crashkernel_low(char *cmdline,
|
|
unsigned long long system_ram,
|
|
unsigned long long *crash_size,
|
|
unsigned long long *crash_base)
|
|
{
|
|
return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base,
|
|
"crashkernel=", suffix_tbl[SUFFIX_LOW]);
|
|
}
|
|
|
|
static void update_vmcoreinfo_note(void)
|
|
{
|
|
u32 *buf = vmcoreinfo_note;
|
|
|
|
if (!vmcoreinfo_size)
|
|
return;
|
|
buf = append_elf_note(buf, VMCOREINFO_NOTE_NAME, 0, vmcoreinfo_data,
|
|
vmcoreinfo_size);
|
|
final_note(buf);
|
|
}
|
|
|
|
void crash_save_vmcoreinfo(void)
|
|
{
|
|
vmcoreinfo_append_str("CRASHTIME=%ld\n", get_seconds());
|
|
update_vmcoreinfo_note();
|
|
}
|
|
|
|
void vmcoreinfo_append_str(const char *fmt, ...)
|
|
{
|
|
va_list args;
|
|
char buf[0x50];
|
|
size_t r;
|
|
|
|
va_start(args, fmt);
|
|
r = vscnprintf(buf, sizeof(buf), fmt, args);
|
|
va_end(args);
|
|
|
|
r = min(r, vmcoreinfo_max_size - vmcoreinfo_size);
|
|
|
|
memcpy(&vmcoreinfo_data[vmcoreinfo_size], buf, r);
|
|
|
|
vmcoreinfo_size += r;
|
|
}
|
|
|
|
/*
|
|
* provide an empty default implementation here -- architecture
|
|
* code may override this
|
|
*/
|
|
void __weak arch_crash_save_vmcoreinfo(void)
|
|
{}
|
|
|
|
unsigned long __weak paddr_vmcoreinfo_note(void)
|
|
{
|
|
return __pa((unsigned long)(char *)&vmcoreinfo_note);
|
|
}
|
|
|
|
static int __init crash_save_vmcoreinfo_init(void)
|
|
{
|
|
VMCOREINFO_OSRELEASE(init_uts_ns.name.release);
|
|
VMCOREINFO_PAGESIZE(PAGE_SIZE);
|
|
|
|
VMCOREINFO_SYMBOL(init_uts_ns);
|
|
VMCOREINFO_SYMBOL(node_online_map);
|
|
#ifdef CONFIG_MMU
|
|
VMCOREINFO_SYMBOL(swapper_pg_dir);
|
|
#endif
|
|
VMCOREINFO_SYMBOL(_stext);
|
|
VMCOREINFO_SYMBOL(vmap_area_list);
|
|
|
|
#ifndef CONFIG_NEED_MULTIPLE_NODES
|
|
VMCOREINFO_SYMBOL(mem_map);
|
|
VMCOREINFO_SYMBOL(contig_page_data);
|
|
#endif
|
|
#ifdef CONFIG_SPARSEMEM
|
|
VMCOREINFO_SYMBOL(mem_section);
|
|
VMCOREINFO_LENGTH(mem_section, NR_SECTION_ROOTS);
|
|
VMCOREINFO_STRUCT_SIZE(mem_section);
|
|
VMCOREINFO_OFFSET(mem_section, section_mem_map);
|
|
#endif
|
|
VMCOREINFO_STRUCT_SIZE(page);
|
|
VMCOREINFO_STRUCT_SIZE(pglist_data);
|
|
VMCOREINFO_STRUCT_SIZE(zone);
|
|
VMCOREINFO_STRUCT_SIZE(free_area);
|
|
VMCOREINFO_STRUCT_SIZE(list_head);
|
|
VMCOREINFO_SIZE(nodemask_t);
|
|
VMCOREINFO_OFFSET(page, flags);
|
|
VMCOREINFO_OFFSET(page, _count);
|
|
VMCOREINFO_OFFSET(page, mapping);
|
|
VMCOREINFO_OFFSET(page, lru);
|
|
VMCOREINFO_OFFSET(page, _mapcount);
|
|
VMCOREINFO_OFFSET(page, private);
|
|
VMCOREINFO_OFFSET(pglist_data, node_zones);
|
|
VMCOREINFO_OFFSET(pglist_data, nr_zones);
|
|
#ifdef CONFIG_FLAT_NODE_MEM_MAP
|
|
VMCOREINFO_OFFSET(pglist_data, node_mem_map);
|
|
#endif
|
|
VMCOREINFO_OFFSET(pglist_data, node_start_pfn);
|
|
VMCOREINFO_OFFSET(pglist_data, node_spanned_pages);
|
|
VMCOREINFO_OFFSET(pglist_data, node_id);
|
|
VMCOREINFO_OFFSET(zone, free_area);
|
|
VMCOREINFO_OFFSET(zone, vm_stat);
|
|
VMCOREINFO_OFFSET(zone, spanned_pages);
|
|
VMCOREINFO_OFFSET(free_area, free_list);
|
|
VMCOREINFO_OFFSET(list_head, next);
|
|
VMCOREINFO_OFFSET(list_head, prev);
|
|
VMCOREINFO_OFFSET(vmap_area, va_start);
|
|
VMCOREINFO_OFFSET(vmap_area, list);
|
|
VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER);
|
|
log_buf_kexec_setup();
|
|
VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES);
|
|
VMCOREINFO_NUMBER(NR_FREE_PAGES);
|
|
VMCOREINFO_NUMBER(PG_lru);
|
|
VMCOREINFO_NUMBER(PG_private);
|
|
VMCOREINFO_NUMBER(PG_swapcache);
|
|
VMCOREINFO_NUMBER(PG_slab);
|
|
#ifdef CONFIG_MEMORY_FAILURE
|
|
VMCOREINFO_NUMBER(PG_hwpoison);
|
|
#endif
|
|
VMCOREINFO_NUMBER(PG_head_mask);
|
|
VMCOREINFO_NUMBER(PAGE_BUDDY_MAPCOUNT_VALUE);
|
|
#ifdef CONFIG_HUGETLBFS
|
|
VMCOREINFO_SYMBOL(free_huge_page);
|
|
#endif
|
|
|
|
arch_crash_save_vmcoreinfo();
|
|
update_vmcoreinfo_note();
|
|
|
|
return 0;
|
|
}
|
|
|
|
subsys_initcall(crash_save_vmcoreinfo_init);
|
|
|
|
#ifdef CONFIG_KEXEC_FILE
|
|
static int locate_mem_hole_top_down(unsigned long start, unsigned long end,
|
|
struct kexec_buf *kbuf)
|
|
{
|
|
struct kimage *image = kbuf->image;
|
|
unsigned long temp_start, temp_end;
|
|
|
|
temp_end = min(end, kbuf->buf_max);
|
|
temp_start = temp_end - kbuf->memsz;
|
|
|
|
do {
|
|
/* align down start */
|
|
temp_start = temp_start & (~(kbuf->buf_align - 1));
|
|
|
|
if (temp_start < start || temp_start < kbuf->buf_min)
|
|
return 0;
|
|
|
|
temp_end = temp_start + kbuf->memsz - 1;
|
|
|
|
/*
|
|
* Make sure this does not conflict with any of existing
|
|
* segments
|
|
*/
|
|
if (kimage_is_destination_range(image, temp_start, temp_end)) {
|
|
temp_start = temp_start - PAGE_SIZE;
|
|
continue;
|
|
}
|
|
|
|
/* We found a suitable memory range */
|
|
break;
|
|
} while (1);
|
|
|
|
/* If we are here, we found a suitable memory range */
|
|
kbuf->mem = temp_start;
|
|
|
|
/* Success, stop navigating through remaining System RAM ranges */
|
|
return 1;
|
|
}
|
|
|
|
static int locate_mem_hole_bottom_up(unsigned long start, unsigned long end,
|
|
struct kexec_buf *kbuf)
|
|
{
|
|
struct kimage *image = kbuf->image;
|
|
unsigned long temp_start, temp_end;
|
|
|
|
temp_start = max(start, kbuf->buf_min);
|
|
|
|
do {
|
|
temp_start = ALIGN(temp_start, kbuf->buf_align);
|
|
temp_end = temp_start + kbuf->memsz - 1;
|
|
|
|
if (temp_end > end || temp_end > kbuf->buf_max)
|
|
return 0;
|
|
/*
|
|
* Make sure this does not conflict with any of existing
|
|
* segments
|
|
*/
|
|
if (kimage_is_destination_range(image, temp_start, temp_end)) {
|
|
temp_start = temp_start + PAGE_SIZE;
|
|
continue;
|
|
}
|
|
|
|
/* We found a suitable memory range */
|
|
break;
|
|
} while (1);
|
|
|
|
/* If we are here, we found a suitable memory range */
|
|
kbuf->mem = temp_start;
|
|
|
|
/* Success, stop navigating through remaining System RAM ranges */
|
|
return 1;
|
|
}
|
|
|
|
static int locate_mem_hole_callback(u64 start, u64 end, void *arg)
|
|
{
|
|
struct kexec_buf *kbuf = (struct kexec_buf *)arg;
|
|
unsigned long sz = end - start + 1;
|
|
|
|
/* Returning 0 will take to next memory range */
|
|
if (sz < kbuf->memsz)
|
|
return 0;
|
|
|
|
if (end < kbuf->buf_min || start > kbuf->buf_max)
|
|
return 0;
|
|
|
|
/*
|
|
* Allocate memory top down with-in ram range. Otherwise bottom up
|
|
* allocation.
|
|
*/
|
|
if (kbuf->top_down)
|
|
return locate_mem_hole_top_down(start, end, kbuf);
|
|
return locate_mem_hole_bottom_up(start, end, kbuf);
|
|
}
|
|
|
|
/*
|
|
* Helper function for placing a buffer in a kexec segment. This assumes
|
|
* that kexec_mutex is held.
|
|
*/
|
|
int kexec_add_buffer(struct kimage *image, char *buffer, unsigned long bufsz,
|
|
unsigned long memsz, unsigned long buf_align,
|
|
unsigned long buf_min, unsigned long buf_max,
|
|
bool top_down, unsigned long *load_addr)
|
|
{
|
|
|
|
struct kexec_segment *ksegment;
|
|
struct kexec_buf buf, *kbuf;
|
|
int ret;
|
|
|
|
/* Currently adding segment this way is allowed only in file mode */
|
|
if (!image->file_mode)
|
|
return -EINVAL;
|
|
|
|
if (image->nr_segments >= KEXEC_SEGMENT_MAX)
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Make sure we are not trying to add buffer after allocating
|
|
* control pages. All segments need to be placed first before
|
|
* any control pages are allocated. As control page allocation
|
|
* logic goes through list of segments to make sure there are
|
|
* no destination overlaps.
|
|
*/
|
|
if (!list_empty(&image->control_pages)) {
|
|
WARN_ON(1);
|
|
return -EINVAL;
|
|
}
|
|
|
|
memset(&buf, 0, sizeof(struct kexec_buf));
|
|
kbuf = &buf;
|
|
kbuf->image = image;
|
|
kbuf->buffer = buffer;
|
|
kbuf->bufsz = bufsz;
|
|
|
|
kbuf->memsz = ALIGN(memsz, PAGE_SIZE);
|
|
kbuf->buf_align = max(buf_align, PAGE_SIZE);
|
|
kbuf->buf_min = buf_min;
|
|
kbuf->buf_max = buf_max;
|
|
kbuf->top_down = top_down;
|
|
|
|
/* Walk the RAM ranges and allocate a suitable range for the buffer */
|
|
if (image->type == KEXEC_TYPE_CRASH)
|
|
ret = walk_iomem_res("Crash kernel",
|
|
IORESOURCE_MEM | IORESOURCE_BUSY,
|
|
crashk_res.start, crashk_res.end, kbuf,
|
|
locate_mem_hole_callback);
|
|
else
|
|
ret = walk_system_ram_res(0, -1, kbuf,
|
|
locate_mem_hole_callback);
|
|
if (ret != 1) {
|
|
/* A suitable memory range could not be found for buffer */
|
|
return -EADDRNOTAVAIL;
|
|
}
|
|
|
|
/* Found a suitable memory range */
|
|
ksegment = &image->segment[image->nr_segments];
|
|
ksegment->kbuf = kbuf->buffer;
|
|
ksegment->bufsz = kbuf->bufsz;
|
|
ksegment->mem = kbuf->mem;
|
|
ksegment->memsz = kbuf->memsz;
|
|
image->nr_segments++;
|
|
*load_addr = ksegment->mem;
|
|
return 0;
|
|
}
|
|
|
|
/* Calculate and store the digest of segments */
|
|
static int kexec_calculate_store_digests(struct kimage *image)
|
|
{
|
|
struct crypto_shash *tfm;
|
|
struct shash_desc *desc;
|
|
int ret = 0, i, j, zero_buf_sz, sha_region_sz;
|
|
size_t desc_size, nullsz;
|
|
char *digest;
|
|
void *zero_buf;
|
|
struct kexec_sha_region *sha_regions;
|
|
struct purgatory_info *pi = &image->purgatory_info;
|
|
|
|
zero_buf = __va(page_to_pfn(ZERO_PAGE(0)) << PAGE_SHIFT);
|
|
zero_buf_sz = PAGE_SIZE;
|
|
|
|
tfm = crypto_alloc_shash("sha256", 0, 0);
|
|
if (IS_ERR(tfm)) {
|
|
ret = PTR_ERR(tfm);
|
|
goto out;
|
|
}
|
|
|
|
desc_size = crypto_shash_descsize(tfm) + sizeof(*desc);
|
|
desc = kzalloc(desc_size, GFP_KERNEL);
|
|
if (!desc) {
|
|
ret = -ENOMEM;
|
|
goto out_free_tfm;
|
|
}
|
|
|
|
sha_region_sz = KEXEC_SEGMENT_MAX * sizeof(struct kexec_sha_region);
|
|
sha_regions = vzalloc(sha_region_sz);
|
|
if (!sha_regions)
|
|
goto out_free_desc;
|
|
|
|
desc->tfm = tfm;
|
|
desc->flags = 0;
|
|
|
|
ret = crypto_shash_init(desc);
|
|
if (ret < 0)
|
|
goto out_free_sha_regions;
|
|
|
|
digest = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
|
|
if (!digest) {
|
|
ret = -ENOMEM;
|
|
goto out_free_sha_regions;
|
|
}
|
|
|
|
for (j = i = 0; i < image->nr_segments; i++) {
|
|
struct kexec_segment *ksegment;
|
|
|
|
ksegment = &image->segment[i];
|
|
/*
|
|
* Skip purgatory as it will be modified once we put digest
|
|
* info in purgatory.
|
|
*/
|
|
if (ksegment->kbuf == pi->purgatory_buf)
|
|
continue;
|
|
|
|
ret = crypto_shash_update(desc, ksegment->kbuf,
|
|
ksegment->bufsz);
|
|
if (ret)
|
|
break;
|
|
|
|
/*
|
|
* Assume rest of the buffer is filled with zero and
|
|
* update digest accordingly.
|
|
*/
|
|
nullsz = ksegment->memsz - ksegment->bufsz;
|
|
while (nullsz) {
|
|
unsigned long bytes = nullsz;
|
|
|
|
if (bytes > zero_buf_sz)
|
|
bytes = zero_buf_sz;
|
|
ret = crypto_shash_update(desc, zero_buf, bytes);
|
|
if (ret)
|
|
break;
|
|
nullsz -= bytes;
|
|
}
|
|
|
|
if (ret)
|
|
break;
|
|
|
|
sha_regions[j].start = ksegment->mem;
|
|
sha_regions[j].len = ksegment->memsz;
|
|
j++;
|
|
}
|
|
|
|
if (!ret) {
|
|
ret = crypto_shash_final(desc, digest);
|
|
if (ret)
|
|
goto out_free_digest;
|
|
ret = kexec_purgatory_get_set_symbol(image, "sha_regions",
|
|
sha_regions, sha_region_sz, 0);
|
|
if (ret)
|
|
goto out_free_digest;
|
|
|
|
ret = kexec_purgatory_get_set_symbol(image, "sha256_digest",
|
|
digest, SHA256_DIGEST_SIZE, 0);
|
|
if (ret)
|
|
goto out_free_digest;
|
|
}
|
|
|
|
out_free_digest:
|
|
kfree(digest);
|
|
out_free_sha_regions:
|
|
vfree(sha_regions);
|
|
out_free_desc:
|
|
kfree(desc);
|
|
out_free_tfm:
|
|
kfree(tfm);
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
/* Actually load purgatory. Lot of code taken from kexec-tools */
|
|
static int __kexec_load_purgatory(struct kimage *image, unsigned long min,
|
|
unsigned long max, int top_down)
|
|
{
|
|
struct purgatory_info *pi = &image->purgatory_info;
|
|
unsigned long align, buf_align, bss_align, buf_sz, bss_sz, bss_pad;
|
|
unsigned long memsz, entry, load_addr, curr_load_addr, bss_addr, offset;
|
|
unsigned char *buf_addr, *src;
|
|
int i, ret = 0, entry_sidx = -1;
|
|
const Elf_Shdr *sechdrs_c;
|
|
Elf_Shdr *sechdrs = NULL;
|
|
void *purgatory_buf = NULL;
|
|
|
|
/*
|
|
* sechdrs_c points to section headers in purgatory and are read
|
|
* only. No modifications allowed.
|
|
*/
|
|
sechdrs_c = (void *)pi->ehdr + pi->ehdr->e_shoff;
|
|
|
|
/*
|
|
* We can not modify sechdrs_c[] and its fields. It is read only.
|
|
* Copy it over to a local copy where one can store some temporary
|
|
* data and free it at the end. We need to modify ->sh_addr and
|
|
* ->sh_offset fields to keep track of permanent and temporary
|
|
* locations of sections.
|
|
*/
|
|
sechdrs = vzalloc(pi->ehdr->e_shnum * sizeof(Elf_Shdr));
|
|
if (!sechdrs)
|
|
return -ENOMEM;
|
|
|
|
memcpy(sechdrs, sechdrs_c, pi->ehdr->e_shnum * sizeof(Elf_Shdr));
|
|
|
|
/*
|
|
* We seem to have multiple copies of sections. First copy is which
|
|
* is embedded in kernel in read only section. Some of these sections
|
|
* will be copied to a temporary buffer and relocated. And these
|
|
* sections will finally be copied to their final destination at
|
|
* segment load time.
|
|
*
|
|
* Use ->sh_offset to reflect section address in memory. It will
|
|
* point to original read only copy if section is not allocatable.
|
|
* Otherwise it will point to temporary copy which will be relocated.
|
|
*
|
|
* Use ->sh_addr to contain final address of the section where it
|
|
* will go during execution time.
|
|
*/
|
|
for (i = 0; i < pi->ehdr->e_shnum; i++) {
|
|
if (sechdrs[i].sh_type == SHT_NOBITS)
|
|
continue;
|
|
|
|
sechdrs[i].sh_offset = (unsigned long)pi->ehdr +
|
|
sechdrs[i].sh_offset;
|
|
}
|
|
|
|
/*
|
|
* Identify entry point section and make entry relative to section
|
|
* start.
|
|
*/
|
|
entry = pi->ehdr->e_entry;
|
|
for (i = 0; i < pi->ehdr->e_shnum; i++) {
|
|
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
|
|
continue;
|
|
|
|
if (!(sechdrs[i].sh_flags & SHF_EXECINSTR))
|
|
continue;
|
|
|
|
/* Make entry section relative */
|
|
if (sechdrs[i].sh_addr <= pi->ehdr->e_entry &&
|
|
((sechdrs[i].sh_addr + sechdrs[i].sh_size) >
|
|
pi->ehdr->e_entry)) {
|
|
entry_sidx = i;
|
|
entry -= sechdrs[i].sh_addr;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Determine how much memory is needed to load relocatable object. */
|
|
buf_align = 1;
|
|
bss_align = 1;
|
|
buf_sz = 0;
|
|
bss_sz = 0;
|
|
|
|
for (i = 0; i < pi->ehdr->e_shnum; i++) {
|
|
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
|
|
continue;
|
|
|
|
align = sechdrs[i].sh_addralign;
|
|
if (sechdrs[i].sh_type != SHT_NOBITS) {
|
|
if (buf_align < align)
|
|
buf_align = align;
|
|
buf_sz = ALIGN(buf_sz, align);
|
|
buf_sz += sechdrs[i].sh_size;
|
|
} else {
|
|
/* bss section */
|
|
if (bss_align < align)
|
|
bss_align = align;
|
|
bss_sz = ALIGN(bss_sz, align);
|
|
bss_sz += sechdrs[i].sh_size;
|
|
}
|
|
}
|
|
|
|
/* Determine the bss padding required to align bss properly */
|
|
bss_pad = 0;
|
|
if (buf_sz & (bss_align - 1))
|
|
bss_pad = bss_align - (buf_sz & (bss_align - 1));
|
|
|
|
memsz = buf_sz + bss_pad + bss_sz;
|
|
|
|
/* Allocate buffer for purgatory */
|
|
purgatory_buf = vzalloc(buf_sz);
|
|
if (!purgatory_buf) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
if (buf_align < bss_align)
|
|
buf_align = bss_align;
|
|
|
|
/* Add buffer to segment list */
|
|
ret = kexec_add_buffer(image, purgatory_buf, buf_sz, memsz,
|
|
buf_align, min, max, top_down,
|
|
&pi->purgatory_load_addr);
|
|
if (ret)
|
|
goto out;
|
|
|
|
/* Load SHF_ALLOC sections */
|
|
buf_addr = purgatory_buf;
|
|
load_addr = curr_load_addr = pi->purgatory_load_addr;
|
|
bss_addr = load_addr + buf_sz + bss_pad;
|
|
|
|
for (i = 0; i < pi->ehdr->e_shnum; i++) {
|
|
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
|
|
continue;
|
|
|
|
align = sechdrs[i].sh_addralign;
|
|
if (sechdrs[i].sh_type != SHT_NOBITS) {
|
|
curr_load_addr = ALIGN(curr_load_addr, align);
|
|
offset = curr_load_addr - load_addr;
|
|
/* We already modifed ->sh_offset to keep src addr */
|
|
src = (char *) sechdrs[i].sh_offset;
|
|
memcpy(buf_addr + offset, src, sechdrs[i].sh_size);
|
|
|
|
/* Store load address and source address of section */
|
|
sechdrs[i].sh_addr = curr_load_addr;
|
|
|
|
/*
|
|
* This section got copied to temporary buffer. Update
|
|
* ->sh_offset accordingly.
|
|
*/
|
|
sechdrs[i].sh_offset = (unsigned long)(buf_addr + offset);
|
|
|
|
/* Advance to the next address */
|
|
curr_load_addr += sechdrs[i].sh_size;
|
|
} else {
|
|
bss_addr = ALIGN(bss_addr, align);
|
|
sechdrs[i].sh_addr = bss_addr;
|
|
bss_addr += sechdrs[i].sh_size;
|
|
}
|
|
}
|
|
|
|
/* Update entry point based on load address of text section */
|
|
if (entry_sidx >= 0)
|
|
entry += sechdrs[entry_sidx].sh_addr;
|
|
|
|
/* Make kernel jump to purgatory after shutdown */
|
|
image->start = entry;
|
|
|
|
/* Used later to get/set symbol values */
|
|
pi->sechdrs = sechdrs;
|
|
|
|
/*
|
|
* Used later to identify which section is purgatory and skip it
|
|
* from checksumming.
|
|
*/
|
|
pi->purgatory_buf = purgatory_buf;
|
|
return ret;
|
|
out:
|
|
vfree(sechdrs);
|
|
vfree(purgatory_buf);
|
|
return ret;
|
|
}
|
|
|
|
static int kexec_apply_relocations(struct kimage *image)
|
|
{
|
|
int i, ret;
|
|
struct purgatory_info *pi = &image->purgatory_info;
|
|
Elf_Shdr *sechdrs = pi->sechdrs;
|
|
|
|
/* Apply relocations */
|
|
for (i = 0; i < pi->ehdr->e_shnum; i++) {
|
|
Elf_Shdr *section, *symtab;
|
|
|
|
if (sechdrs[i].sh_type != SHT_RELA &&
|
|
sechdrs[i].sh_type != SHT_REL)
|
|
continue;
|
|
|
|
/*
|
|
* For section of type SHT_RELA/SHT_REL,
|
|
* ->sh_link contains section header index of associated
|
|
* symbol table. And ->sh_info contains section header
|
|
* index of section to which relocations apply.
|
|
*/
|
|
if (sechdrs[i].sh_info >= pi->ehdr->e_shnum ||
|
|
sechdrs[i].sh_link >= pi->ehdr->e_shnum)
|
|
return -ENOEXEC;
|
|
|
|
section = &sechdrs[sechdrs[i].sh_info];
|
|
symtab = &sechdrs[sechdrs[i].sh_link];
|
|
|
|
if (!(section->sh_flags & SHF_ALLOC))
|
|
continue;
|
|
|
|
/*
|
|
* symtab->sh_link contain section header index of associated
|
|
* string table.
|
|
*/
|
|
if (symtab->sh_link >= pi->ehdr->e_shnum)
|
|
/* Invalid section number? */
|
|
continue;
|
|
|
|
/*
|
|
* Respective architecture needs to provide support for applying
|
|
* relocations of type SHT_RELA/SHT_REL.
|
|
*/
|
|
if (sechdrs[i].sh_type == SHT_RELA)
|
|
ret = arch_kexec_apply_relocations_add(pi->ehdr,
|
|
sechdrs, i);
|
|
else if (sechdrs[i].sh_type == SHT_REL)
|
|
ret = arch_kexec_apply_relocations(pi->ehdr,
|
|
sechdrs, i);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Load relocatable purgatory object and relocate it appropriately */
|
|
int kexec_load_purgatory(struct kimage *image, unsigned long min,
|
|
unsigned long max, int top_down,
|
|
unsigned long *load_addr)
|
|
{
|
|
struct purgatory_info *pi = &image->purgatory_info;
|
|
int ret;
|
|
|
|
if (kexec_purgatory_size <= 0)
|
|
return -EINVAL;
|
|
|
|
if (kexec_purgatory_size < sizeof(Elf_Ehdr))
|
|
return -ENOEXEC;
|
|
|
|
pi->ehdr = (Elf_Ehdr *)kexec_purgatory;
|
|
|
|
if (memcmp(pi->ehdr->e_ident, ELFMAG, SELFMAG) != 0
|
|
|| pi->ehdr->e_type != ET_REL
|
|
|| !elf_check_arch(pi->ehdr)
|
|
|| pi->ehdr->e_shentsize != sizeof(Elf_Shdr))
|
|
return -ENOEXEC;
|
|
|
|
if (pi->ehdr->e_shoff >= kexec_purgatory_size
|
|
|| (pi->ehdr->e_shnum * sizeof(Elf_Shdr) >
|
|
kexec_purgatory_size - pi->ehdr->e_shoff))
|
|
return -ENOEXEC;
|
|
|
|
ret = __kexec_load_purgatory(image, min, max, top_down);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = kexec_apply_relocations(image);
|
|
if (ret)
|
|
goto out;
|
|
|
|
*load_addr = pi->purgatory_load_addr;
|
|
return 0;
|
|
out:
|
|
vfree(pi->sechdrs);
|
|
vfree(pi->purgatory_buf);
|
|
return ret;
|
|
}
|
|
|
|
static Elf_Sym *kexec_purgatory_find_symbol(struct purgatory_info *pi,
|
|
const char *name)
|
|
{
|
|
Elf_Sym *syms;
|
|
Elf_Shdr *sechdrs;
|
|
Elf_Ehdr *ehdr;
|
|
int i, k;
|
|
const char *strtab;
|
|
|
|
if (!pi->sechdrs || !pi->ehdr)
|
|
return NULL;
|
|
|
|
sechdrs = pi->sechdrs;
|
|
ehdr = pi->ehdr;
|
|
|
|
for (i = 0; i < ehdr->e_shnum; i++) {
|
|
if (sechdrs[i].sh_type != SHT_SYMTAB)
|
|
continue;
|
|
|
|
if (sechdrs[i].sh_link >= ehdr->e_shnum)
|
|
/* Invalid strtab section number */
|
|
continue;
|
|
strtab = (char *)sechdrs[sechdrs[i].sh_link].sh_offset;
|
|
syms = (Elf_Sym *)sechdrs[i].sh_offset;
|
|
|
|
/* Go through symbols for a match */
|
|
for (k = 0; k < sechdrs[i].sh_size/sizeof(Elf_Sym); k++) {
|
|
if (ELF_ST_BIND(syms[k].st_info) != STB_GLOBAL)
|
|
continue;
|
|
|
|
if (strcmp(strtab + syms[k].st_name, name) != 0)
|
|
continue;
|
|
|
|
if (syms[k].st_shndx == SHN_UNDEF ||
|
|
syms[k].st_shndx >= ehdr->e_shnum) {
|
|
pr_debug("Symbol: %s has bad section index %d.\n",
|
|
name, syms[k].st_shndx);
|
|
return NULL;
|
|
}
|
|
|
|
/* Found the symbol we are looking for */
|
|
return &syms[k];
|
|
}
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
void *kexec_purgatory_get_symbol_addr(struct kimage *image, const char *name)
|
|
{
|
|
struct purgatory_info *pi = &image->purgatory_info;
|
|
Elf_Sym *sym;
|
|
Elf_Shdr *sechdr;
|
|
|
|
sym = kexec_purgatory_find_symbol(pi, name);
|
|
if (!sym)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
sechdr = &pi->sechdrs[sym->st_shndx];
|
|
|
|
/*
|
|
* Returns the address where symbol will finally be loaded after
|
|
* kexec_load_segment()
|
|
*/
|
|
return (void *)(sechdr->sh_addr + sym->st_value);
|
|
}
|
|
|
|
/*
|
|
* Get or set value of a symbol. If "get_value" is true, symbol value is
|
|
* returned in buf otherwise symbol value is set based on value in buf.
|
|
*/
|
|
int kexec_purgatory_get_set_symbol(struct kimage *image, const char *name,
|
|
void *buf, unsigned int size, bool get_value)
|
|
{
|
|
Elf_Sym *sym;
|
|
Elf_Shdr *sechdrs;
|
|
struct purgatory_info *pi = &image->purgatory_info;
|
|
char *sym_buf;
|
|
|
|
sym = kexec_purgatory_find_symbol(pi, name);
|
|
if (!sym)
|
|
return -EINVAL;
|
|
|
|
if (sym->st_size != size) {
|
|
pr_err("symbol %s size mismatch: expected %lu actual %u\n",
|
|
name, (unsigned long)sym->st_size, size);
|
|
return -EINVAL;
|
|
}
|
|
|
|
sechdrs = pi->sechdrs;
|
|
|
|
if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
|
|
pr_err("symbol %s is in a bss section. Cannot %s\n", name,
|
|
get_value ? "get" : "set");
|
|
return -EINVAL;
|
|
}
|
|
|
|
sym_buf = (unsigned char *)sechdrs[sym->st_shndx].sh_offset +
|
|
sym->st_value;
|
|
|
|
if (get_value)
|
|
memcpy((void *)buf, sym_buf, size);
|
|
else
|
|
memcpy((void *)sym_buf, buf, size);
|
|
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_KEXEC_FILE */
|
|
|
|
/*
|
|
* Move into place and start executing a preloaded standalone
|
|
* executable. If nothing was preloaded return an error.
|
|
*/
|
|
int kernel_kexec(void)
|
|
{
|
|
int error = 0;
|
|
|
|
if (!mutex_trylock(&kexec_mutex))
|
|
return -EBUSY;
|
|
if (!kexec_image) {
|
|
error = -EINVAL;
|
|
goto Unlock;
|
|
}
|
|
|
|
#ifdef CONFIG_KEXEC_JUMP
|
|
if (kexec_image->preserve_context) {
|
|
lock_system_sleep();
|
|
pm_prepare_console();
|
|
error = freeze_processes();
|
|
if (error) {
|
|
error = -EBUSY;
|
|
goto Restore_console;
|
|
}
|
|
suspend_console();
|
|
error = dpm_suspend_start(PMSG_FREEZE);
|
|
if (error)
|
|
goto Resume_console;
|
|
/* At this point, dpm_suspend_start() has been called,
|
|
* but *not* dpm_suspend_end(). We *must* call
|
|
* dpm_suspend_end() now. Otherwise, drivers for
|
|
* some devices (e.g. interrupt controllers) become
|
|
* desynchronized with the actual state of the
|
|
* hardware at resume time, and evil weirdness ensues.
|
|
*/
|
|
error = dpm_suspend_end(PMSG_FREEZE);
|
|
if (error)
|
|
goto Resume_devices;
|
|
error = disable_nonboot_cpus();
|
|
if (error)
|
|
goto Enable_cpus;
|
|
local_irq_disable();
|
|
error = syscore_suspend();
|
|
if (error)
|
|
goto Enable_irqs;
|
|
} else
|
|
#endif
|
|
{
|
|
kexec_in_progress = true;
|
|
kernel_restart_prepare(NULL);
|
|
migrate_to_reboot_cpu();
|
|
|
|
/*
|
|
* migrate_to_reboot_cpu() disables CPU hotplug assuming that
|
|
* no further code needs to use CPU hotplug (which is true in
|
|
* the reboot case). However, the kexec path depends on using
|
|
* CPU hotplug again; so re-enable it here.
|
|
*/
|
|
cpu_hotplug_enable();
|
|
pr_emerg("Starting new kernel\n");
|
|
machine_shutdown();
|
|
}
|
|
|
|
machine_kexec(kexec_image);
|
|
|
|
#ifdef CONFIG_KEXEC_JUMP
|
|
if (kexec_image->preserve_context) {
|
|
syscore_resume();
|
|
Enable_irqs:
|
|
local_irq_enable();
|
|
Enable_cpus:
|
|
enable_nonboot_cpus();
|
|
dpm_resume_start(PMSG_RESTORE);
|
|
Resume_devices:
|
|
dpm_resume_end(PMSG_RESTORE);
|
|
Resume_console:
|
|
resume_console();
|
|
thaw_processes();
|
|
Restore_console:
|
|
pm_restore_console();
|
|
unlock_system_sleep();
|
|
}
|
|
#endif
|
|
|
|
Unlock:
|
|
mutex_unlock(&kexec_mutex);
|
|
return error;
|
|
}
|