[PATCH 5/7] prepare the dump loads for kcore analysis
Baoquan He
bhe at redhat.com
Fri Jul 11 00:16:02 PDT 2014
In kcore, only "System Ram" and "kernel text" program segments
are needed. And to be more precise, exclude the crashkernel
memory range.
Signed-off-by: Baoquan He <bhe at redhat.com>
---
elf_info.c | 135 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
elf_info.h | 1 +
2 files changed, 136 insertions(+)
diff --git a/elf_info.c b/elf_info.c
index 1a3e3bd..ca63d34 100644
--- a/elf_info.c
+++ b/elf_info.c
@@ -779,6 +779,141 @@ get_elf_loads(int fd, char *filename)
return TRUE;
}
+static int exclude_segment(struct pt_load_segment **pt_loads, unsigned int *num_pt_loads, uint64_t start, uint64_t end)
+{
+ int i, j, tidx = -1;
+ unsigned long long vstart, vend, kvstart, kvend;
+ struct pt_load_segment temp_seg = {0};
+ kvstart = (ulong)start | PAGE_OFFSET;
+ kvend = (ulong)end | PAGE_OFFSET;
+ unsigned long size;
+
+ for (i = 0; i < (*num_pt_loads); i++) {
+ vstart = (*pt_loads)[i].virt_start;
+ vend = (*pt_loads)[i].virt_end;
+ if (kvstart < vend && kvend > vstart) {
+ if (kvstart != vstart && kvend != vend) {
+ /* Split load segment */
+ temp_seg.phys_start = end +1;
+ temp_seg.phys_end = (*pt_loads)[i].phys_end;
+ temp_seg.virt_start = kvend + 1;
+ temp_seg.virt_end = vend;
+ temp_seg.file_offset = (*pt_loads)[i].file_offset + temp_seg.virt_start - (*pt_loads)[i].virt_start;
+
+ (*pt_loads)[i].virt_end = kvstart - 1;
+ (*pt_loads)[i].phys_end = start -1;
+
+ tidx = i+1;
+ } else if (kvstart != vstart) {
+ (*pt_loads)[i].phys_end = start - 1;
+ (*pt_loads)[i].virt_end = kvstart - 1;
+ } else {
+ (*pt_loads)[i].phys_start = end + 1;
+ (*pt_loads)[i].virt_start = kvend + 1;
+ }
+ }
+ }
+ /* Insert split load segment, if any. */
+ if (tidx >= 0) {
+ size = (*num_pt_loads + 1) * sizeof((*pt_loads)[0]);
+ (*pt_loads) = realloc((*pt_loads), size);
+ if (!(*pt_loads) ) {
+ ERRMSG("Cannot realloc %ld bytes: %s\n",
+ size + 0UL, strerror(errno));
+ exit(1);
+ }
+ for (j = (*num_pt_loads - 1); j >= tidx; j--)
+ (*pt_loads)[j+1] = (*pt_loads)[j];
+ (*pt_loads)[tidx] = temp_seg;
+ (*num_pt_loads)++;
+ }
+ return 0;
+}
+
+static int
+process_dump_load(struct pt_load_segment *pls)
+{
+ unsigned long long paddr;
+
+ paddr = vaddr_to_paddr(pls->virt_start);
+ pls->phys_start = paddr;
+ pls->phys_end = paddr + (pls->virt_end - pls->virt_start);
+ DEBUG_MSG("process_dump_load\n");
+ DEBUG_MSG(" phys_start : %llx\n", pls->phys_start);
+ DEBUG_MSG(" phys_end : %llx\n", pls->phys_end);
+ DEBUG_MSG(" virt_start : %llx\n", pls->virt_start);
+ DEBUG_MSG(" virt_end : %llx\n", pls->virt_end);
+
+ return TRUE;
+}
+
+int get_kcore_dump_loads()
+{
+ struct pt_load_segment *pls;
+ int i, j, loads=0;
+ unsigned long long paddr;
+
+ for (i = 0; i < num_pt_loads; ++i) {
+ struct pt_load_segment *p = &pt_loads[i];
+ if (is_vmalloc_addr(p->virt_start))
+ continue;
+ loads++;
+ }
+
+ pls = calloc(sizeof(struct pt_load_segment), loads);
+ if (pls == NULL) {
+ ERRMSG("Can't allocate memory for the PT_LOAD. %s\n",
+ strerror(errno));
+ return FALSE;
+ }
+
+ for (i = 0, j=0; i < num_pt_loads; ++i) {
+ struct pt_load_segment *p = &pt_loads[i];
+ if (is_vmalloc_addr(p->virt_start))
+ continue;
+ if (j >= loads)
+ return FALSE;
+
+ if (j == 0) {
+ offset_pt_load_memory = p->file_offset;
+ if (offset_pt_load_memory == 0) {
+ ERRMSG("Can't get the offset of page data.\n");
+ return FALSE;
+ }
+ }
+
+ pls[j] = *p;
+ process_dump_load(&pls[j]);
+ j++;
+ }
+
+ free(pt_loads);
+ pt_loads = pls;
+ num_pt_loads = loads;
+
+ for (i=0; i<crash_reserved_mem_nr; i++)
+ {
+ exclude_segment(&pt_loads, &num_pt_loads, crash_reserved_mem[i].start, crash_reserved_mem[i].end);
+ }
+
+ max_file_offset = 0;
+ for (i = 0; i < num_pt_loads; ++i) {
+ struct pt_load_segment *p = &pt_loads[i];
+ max_file_offset = MAX(max_file_offset,
+ p->file_offset + p->phys_end - p->phys_start);
+ }
+
+ for (i = 0; i < num_pt_loads; ++i) {
+ struct pt_load_segment *p = &pt_loads[i];
+ DEBUG_MSG("LOAD (%d)\n", i);
+ DEBUG_MSG(" phys_start : %llx\n", p->phys_start);
+ DEBUG_MSG(" phys_end : %llx\n", p->phys_end);
+ DEBUG_MSG(" virt_start : %llx\n", p->virt_start);
+ DEBUG_MSG(" virt_end : %llx\n", p->virt_end);
+ }
+
+ return TRUE;
+}
/*
* Get ELF information about /proc/vmcore.
diff --git a/elf_info.h b/elf_info.h
index 3ce0138..ba27fdf 100644
--- a/elf_info.h
+++ b/elf_info.h
@@ -46,6 +46,7 @@ int get_elf_info(int fd, char *filename);
void free_elf_info(void);
int get_elf_loads(int fd, char *filename);
int set_kcore_vmcoreinfo(uint64_t vmcoreinfo_addr, uint64_t vmcoreinfo_len);
+int get_kcore_dump_loads();
int is_elf64_memory(void);
int is_xen_memory(void);
--
1.8.4.2
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