static atomic_t cpus_in_fadump;
static DEFINE_MUTEX(fadump_mutex);
-static struct fadump_mrange_info crash_mrange_info = { "crash", NULL, 0, 0, 0, false };
-
#define RESERVED_RNGS_SZ 16384 /* 16K - 128 entries */
#define RESERVED_RNGS_CNT (RESERVED_RNGS_SZ / \
sizeof(struct fadump_memory_range))
size = PAGE_ALIGN(size);
size += fw_dump.boot_memory_size;
size += sizeof(struct fadump_crash_info_header);
- size += sizeof(struct elfhdr); /* ELF core header.*/
- size += sizeof(struct elf_phdr); /* place holder for cpu notes */
- /* Program headers for crash memory regions. */
- size += sizeof(struct elf_phdr) * (memblock_num_regions(memory) + 2);
-
- size = PAGE_ALIGN(size);
/* This is to hold kernel metadata on platforms that support it */
size += (fw_dump.ops->fadump_get_metadata_size ?
return 0;
}
-static int fadump_exclude_reserved_area(u64 start, u64 end)
-{
- u64 ra_start, ra_end;
- int ret = 0;
-
- ra_start = fw_dump.reserve_dump_area_start;
- ra_end = ra_start + fw_dump.reserve_dump_area_size;
-
- if ((ra_start < end) && (ra_end > start)) {
- if ((start < ra_start) && (end > ra_end)) {
- ret = fadump_add_mem_range(&crash_mrange_info,
- start, ra_start);
- if (ret)
- return ret;
-
- ret = fadump_add_mem_range(&crash_mrange_info,
- ra_end, end);
- } else if (start < ra_start) {
- ret = fadump_add_mem_range(&crash_mrange_info,
- start, ra_start);
- } else if (ra_end < end) {
- ret = fadump_add_mem_range(&crash_mrange_info,
- ra_end, end);
- }
- } else
- ret = fadump_add_mem_range(&crash_mrange_info, start, end);
-
- return ret;
-}
-
static int fadump_init_elfcore_header(char *bufp)
{
struct elfhdr *elf;
return 0;
}
-/*
- * Traverse through memblock structure and setup crash memory ranges. These
- * ranges will be used create PT_LOAD program headers in elfcore header.
- */
-static int fadump_setup_crash_memory_ranges(void)
-{
- u64 i, start, end;
- int ret;
-
- pr_debug("Setup crash memory ranges.\n");
- crash_mrange_info.mem_range_cnt = 0;
-
- /*
- * Boot memory region(s) registered with firmware are moved to
- * different location at the time of crash. Create separate program
- * header(s) for this memory chunk(s) with the correct offset.
- */
- for (i = 0; i < fw_dump.boot_mem_regs_cnt; i++) {
- start = fw_dump.boot_mem_addr[i];
- end = start + fw_dump.boot_mem_sz[i];
- ret = fadump_add_mem_range(&crash_mrange_info, start, end);
- if (ret)
- return ret;
- }
-
- for_each_mem_range(i, &start, &end) {
- /*
- * skip the memory chunk that is already added
- * (0 through boot_memory_top).
- */
- if (start < fw_dump.boot_mem_top) {
- if (end > fw_dump.boot_mem_top)
- start = fw_dump.boot_mem_top;
- else
- continue;
- }
-
- /* add this range excluding the reserved dump area. */
- ret = fadump_exclude_reserved_area(start, end);
- if (ret)
- return ret;
- }
-
- return 0;
-}
-
/*
* If the given physical address falls within the boot memory region then
* return the relocated address that points to the dump region reserved
return raddr;
}
-static int fadump_create_elfcore_headers(char *bufp)
+static void __init populate_elf_pt_load(struct elf_phdr *phdr, u64 start,
+ u64 size, unsigned long long offset)
{
- unsigned long long raddr, offset;
- struct elf_phdr *phdr;
+ phdr->p_align = 0;
+ phdr->p_memsz = size;
+ phdr->p_filesz = size;
+ phdr->p_paddr = start;
+ phdr->p_offset = offset;
+ phdr->p_type = PT_LOAD;
+ phdr->p_flags = PF_R|PF_W|PF_X;
+ phdr->p_vaddr = (unsigned long)__va(start);
+}
+
+static void __init fadump_populate_elfcorehdr(struct fadump_crash_info_header *fdh)
+{
+ char *bufp;
struct elfhdr *elf;
- int i, j;
+ struct elf_phdr *phdr;
+ u64 boot_mem_dest_offset;
+ unsigned long long i, ra_start, ra_end, ra_size, mstart, mend;
+ bufp = (char *) fw_dump.elfcorehdr_addr;
fadump_init_elfcore_header(bufp);
elf = (struct elfhdr *)bufp;
bufp += sizeof(struct elfhdr);
/*
- * setup ELF PT_NOTE, place holder for cpu notes info. The notes info
- * will be populated during second kernel boot after crash. Hence
- * this PT_NOTE will always be the first elf note.
+ * Set up ELF PT_NOTE, a placeholder for CPU notes information.
+ * The notes info will be populated later by platform-specific code.
+ * Hence, this PT_NOTE will always be the first ELF note.
*
* NOTE: Any new ELF note addition should be placed after this note.
*/
phdr = (struct elf_phdr *)bufp;
bufp += sizeof(struct elf_phdr);
phdr->p_type = PT_NOTE;
- phdr->p_flags = 0;
- phdr->p_vaddr = 0;
- phdr->p_align = 0;
-
- phdr->p_offset = 0;
- phdr->p_paddr = 0;
- phdr->p_filesz = 0;
- phdr->p_memsz = 0;
-
+ phdr->p_flags = 0;
+ phdr->p_vaddr = 0;
+ phdr->p_align = 0;
+ phdr->p_offset = 0;
+ phdr->p_paddr = 0;
+ phdr->p_filesz = 0;
+ phdr->p_memsz = 0;
+ /* Increment number of program headers. */
(elf->e_phnum)++;
/* setup ELF PT_NOTE for vmcoreinfo */
phdr->p_flags = 0;
phdr->p_vaddr = 0;
phdr->p_align = 0;
-
- phdr->p_paddr = fadump_relocate(paddr_vmcoreinfo_note());
- phdr->p_offset = phdr->p_paddr;
- phdr->p_memsz = phdr->p_filesz = VMCOREINFO_NOTE_SIZE;
-
+ phdr->p_paddr = phdr->p_offset = fdh->vmcoreinfo_raddr;
+ phdr->p_memsz = phdr->p_filesz = fdh->vmcoreinfo_size;
/* Increment number of program headers. */
(elf->e_phnum)++;
- /* setup PT_LOAD sections. */
- j = 0;
- offset = 0;
- raddr = fw_dump.boot_mem_addr[0];
- for (i = 0; i < crash_mrange_info.mem_range_cnt; i++) {
- u64 mbase, msize;
-
- mbase = crash_mrange_info.mem_ranges[i].base;
- msize = crash_mrange_info.mem_ranges[i].size;
- if (!msize)
- continue;
-
+ /*
+ * Setup PT_LOAD sections. first include boot memory regions
+ * and then add rest of the memory regions.
+ */
+ boot_mem_dest_offset = fw_dump.boot_mem_dest_addr;
+ for (i = 0; i < fw_dump.boot_mem_regs_cnt; i++) {
phdr = (struct elf_phdr *)bufp;
bufp += sizeof(struct elf_phdr);
- phdr->p_type = PT_LOAD;
- phdr->p_flags = PF_R|PF_W|PF_X;
- phdr->p_offset = mbase;
-
- if (mbase == raddr) {
- /*
- * The entire real memory region will be moved by
- * firmware to the specified destination_address.
- * Hence set the correct offset.
- */
- phdr->p_offset = fw_dump.boot_mem_dest_addr + offset;
- if (j < (fw_dump.boot_mem_regs_cnt - 1)) {
- offset += fw_dump.boot_mem_sz[j];
- raddr = fw_dump.boot_mem_addr[++j];
- }
+ populate_elf_pt_load(phdr, fw_dump.boot_mem_addr[i],
+ fw_dump.boot_mem_sz[i],
+ boot_mem_dest_offset);
+ /* Increment number of program headers. */
+ (elf->e_phnum)++;
+ boot_mem_dest_offset += fw_dump.boot_mem_sz[i];
+ }
+
+ /* Memory reserved for fadump in first kernel */
+ ra_start = fw_dump.reserve_dump_area_start;
+ ra_size = get_fadump_area_size();
+ ra_end = ra_start + ra_size;
+
+ phdr = (struct elf_phdr *)bufp;
+ for_each_mem_range(i, &mstart, &mend) {
+ /* Boot memory regions already added, skip them now */
+ if (mstart < fw_dump.boot_mem_top) {
+ if (mend > fw_dump.boot_mem_top)
+ mstart = fw_dump.boot_mem_top;
+ else
+ continue;
}
- phdr->p_paddr = mbase;
- phdr->p_vaddr = (unsigned long)__va(mbase);
- phdr->p_filesz = msize;
- phdr->p_memsz = msize;
- phdr->p_align = 0;
+ /* Handle memblock regions overlaps with fadump reserved area */
+ if ((ra_start < mend) && (ra_end > mstart)) {
+ if ((mstart < ra_start) && (mend > ra_end)) {
+ populate_elf_pt_load(phdr, mstart, ra_start - mstart, mstart);
+ /* Increment number of program headers. */
+ (elf->e_phnum)++;
+ bufp += sizeof(struct elf_phdr);
+ phdr = (struct elf_phdr *)bufp;
+ populate_elf_pt_load(phdr, ra_end, mend - ra_end, ra_end);
+ } else if (mstart < ra_start) {
+ populate_elf_pt_load(phdr, mstart, ra_start - mstart, mstart);
+ } else if (ra_end < mend) {
+ populate_elf_pt_load(phdr, ra_end, mend - ra_end, ra_end);
+ }
+ } else {
+ /* No overlap with fadump reserved memory region */
+ populate_elf_pt_load(phdr, mstart, mend - mstart, mstart);
+ }
/* Increment number of program headers. */
(elf->e_phnum)++;
+ bufp += sizeof(struct elf_phdr);
+ phdr = (struct elf_phdr *) bufp;
}
- return 0;
}
static unsigned long init_fadump_header(unsigned long addr)
memset(fdh, 0, sizeof(struct fadump_crash_info_header));
fdh->magic_number = FADUMP_CRASH_INFO_MAGIC;
- fdh->elfcorehdr_addr = addr;
+ fdh->version = FADUMP_HEADER_VERSION;
/* We will set the crashing cpu id in crash_fadump() during crash. */
fdh->crashing_cpu = FADUMP_CPU_UNKNOWN;
+
+ /*
+ * The physical address and size of vmcoreinfo are required in the
+ * second kernel to prepare elfcorehdr.
+ */
+ fdh->vmcoreinfo_raddr = fadump_relocate(paddr_vmcoreinfo_note());
+ fdh->vmcoreinfo_size = VMCOREINFO_NOTE_SIZE;
+
+
+ fdh->pt_regs_sz = sizeof(struct pt_regs);
/*
* When LPAR is terminated by PYHP, ensure all possible CPUs'
* register data is processed while exporting the vmcore.
*/
fdh->cpu_mask = *cpu_possible_mask;
+ fdh->cpu_mask_sz = sizeof(struct cpumask);
return addr;
}
static int register_fadump(void)
{
unsigned long addr;
- void *vaddr;
- int ret;
/*
* If no memory is reserved then we can not register for firmware-
if (!fw_dump.reserve_dump_area_size)
return -ENODEV;
- ret = fadump_setup_crash_memory_ranges();
- if (ret)
- return ret;
-
addr = fw_dump.fadumphdr_addr;
/* Initialize fadump crash info header. */
addr = init_fadump_header(addr);
- vaddr = __va(addr);
-
- pr_debug("Creating ELF core headers at %#016lx\n", addr);
- fadump_create_elfcore_headers(vaddr);
/* register the future kernel dump with firmware. */
pr_debug("Registering for firmware-assisted kernel dump...\n");
} else if (fw_dump.dump_registered) {
/* Un-register Firmware-assisted dump if it was registered. */
fw_dump.ops->fadump_unregister(&fw_dump);
- fadump_free_mem_ranges(&crash_mrange_info);
}
if (fw_dump.ops->fadump_cleanup)
fadump_release_reserved_area(tstart, end);
}
+static void fadump_free_elfcorehdr_buf(void)
+{
+ if (fw_dump.elfcorehdr_addr == 0 || fw_dump.elfcorehdr_size == 0)
+ return;
+
+ /*
+ * Before freeing the memory of `elfcorehdr`, reset the global
+ * `elfcorehdr_addr` to prevent modules like `vmcore` from accessing
+ * invalid memory.
+ */
+ elfcorehdr_addr = ELFCORE_ADDR_ERR;
+ fadump_free_buffer(fw_dump.elfcorehdr_addr, fw_dump.elfcorehdr_size);
+ fw_dump.elfcorehdr_addr = 0;
+ fw_dump.elfcorehdr_size = 0;
+}
+
static void fadump_invalidate_release_mem(void)
{
mutex_lock(&fadump_mutex);
fadump_cleanup();
mutex_unlock(&fadump_mutex);
+ fadump_free_elfcorehdr_buf();
fadump_release_memory(fw_dump.boot_mem_top, memblock_end_of_DRAM());
fadump_free_cpu_notes_buf();
return;
}
+static int __init fadump_setup_elfcorehdr_buf(void)
+{
+ int elf_phdr_cnt;
+ unsigned long elfcorehdr_size;
+
+ /*
+ * Program header for CPU notes comes first, followed by one for
+ * vmcoreinfo, and the remaining program headers correspond to
+ * memory regions.
+ */
+ elf_phdr_cnt = 2 + fw_dump.boot_mem_regs_cnt + memblock_num_regions(memory);
+ elfcorehdr_size = sizeof(struct elfhdr) + (elf_phdr_cnt * sizeof(struct elf_phdr));
+ elfcorehdr_size = PAGE_ALIGN(elfcorehdr_size);
+
+ fw_dump.elfcorehdr_addr = (u64)fadump_alloc_buffer(elfcorehdr_size);
+ if (!fw_dump.elfcorehdr_addr) {
+ pr_err("Failed to allocate %lu bytes for elfcorehdr\n",
+ elfcorehdr_size);
+ return -ENOMEM;
+ }
+ fw_dump.elfcorehdr_size = elfcorehdr_size;
+ return 0;
+}
+
+/*
+ * Check if the fadump header of crashed kernel is compatible with fadump kernel.
+ *
+ * It checks the magic number, endianness, and size of non-primitive type
+ * members of fadump header to ensure safe dump collection.
+ */
+static bool __init is_fadump_header_compatible(struct fadump_crash_info_header *fdh)
+{
+ if (fdh->magic_number == FADUMP_CRASH_INFO_MAGIC_OLD) {
+ pr_err("Old magic number, can't process the dump.\n");
+ return false;
+ }
+
+ if (fdh->magic_number != FADUMP_CRASH_INFO_MAGIC) {
+ if (fdh->magic_number == swab64(FADUMP_CRASH_INFO_MAGIC))
+ pr_err("Endianness mismatch between the crashed and fadump kernels.\n");
+ else
+ pr_err("Fadump header is corrupted.\n");
+
+ return false;
+ }
+
+ /*
+ * Dump collection is not safe if the size of non-primitive type members
+ * of the fadump header do not match between crashed and fadump kernel.
+ */
+ if (fdh->pt_regs_sz != sizeof(struct pt_regs) ||
+ fdh->cpu_mask_sz != sizeof(struct cpumask)) {
+ pr_err("Fadump header size mismatch.\n");
+ return false;
+ }
+
+ return true;
+}
+
+static void __init fadump_process(void)
+{
+ struct fadump_crash_info_header *fdh;
+
+ fdh = (struct fadump_crash_info_header *) __va(fw_dump.fadumphdr_addr);
+ if (!fdh) {
+ pr_err("Crash info header is empty.\n");
+ goto err_out;
+ }
+
+ /* Avoid processing the dump if fadump header isn't compatible */
+ if (!is_fadump_header_compatible(fdh))
+ goto err_out;
+
+ /* Allocate buffer for elfcorehdr */
+ if (fadump_setup_elfcorehdr_buf())
+ goto err_out;
+
+ fadump_populate_elfcorehdr(fdh);
+
+ /* Let platform update the CPU notes in elfcorehdr */
+ if (fw_dump.ops->fadump_process(&fw_dump) < 0)
+ goto err_out;
+
+ /*
+ * elfcorehdr is now ready to be exported.
+ *
+ * set elfcorehdr_addr so that vmcore module will export the
+ * elfcorehdr through '/proc/vmcore'.
+ */
+ elfcorehdr_addr = virt_to_phys((void *)fw_dump.elfcorehdr_addr);
+ return;
+
+err_out:
+ fadump_invalidate_release_mem();
+}
+
/*
* Prepare for firmware-assisted dump.
*/
* saving it to the disk.
*/
if (fw_dump.dump_active) {
- /*
- * if dump process fails then invalidate the registration
- * and release memory before proceeding for re-registration.
- */
- if (fw_dump.ops->fadump_process(&fw_dump) < 0)
- fadump_invalidate_release_mem();
+ fadump_process();
}
/* Initialize the kernel dump memory structure and register with f/w */
else if (fw_dump.reserve_dump_area_size) {
projects / linux.git / commitdiff