Hi Alan,
Here is a backport of the sparse core writing for 2.2. It never made
any problems on 2.[34] and makes live much easier for us.
Could you apply this to 2.2.19?
Greetings
Christoph
diff -uNr 2.2.18/fs/binfmt_elf.c c/fs/binfmt_elf.c
--- 2.2.18/fs/binfmt_elf.c Mon Dec 11 01:49:44 2000
+++ c/fs/binfmt_elf.c Tue Dec 19 19:45:55 2000
@@ -1056,7 +1056,7 @@
#undef DUMP_SEEK
#define DUMP_WRITE(addr, nr) \
- if (!dump_write(file, (addr), (nr))) \
+ if ((size += (nr)) > limit || !dump_write(file, (addr), (nr))) \
goto close_coredump;
#define DUMP_SEEK(off) \
if (!dump_seek(file, (off))) \
@@ -1078,7 +1078,7 @@
char corefile[6+sizeof(current->comm)];
int segs;
int i;
- size_t size;
+ size_t size = 0;
struct vm_area_struct *vma;
struct elfhdr elf;
off_t offset = 0, dataoff;
@@ -1099,24 +1099,10 @@
MOD_INC_USE_COUNT;
#endif
- /* Count what's needed to dump, up to the limit of coredump size */
- segs = 0;
- size = 0;
- for(vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
- if (maydump(vma))
- {
- unsigned long sz = vma->vm_end-vma->vm_start;
-
- if (size+sz >= limit)
- break;
- else
- size += sz;
- }
+ segs = current->mm->map_count;
- segs++;
- }
#ifdef DEBUG
- printk("elf_core_dump: %d segs taking %d bytes\n", segs, size);
+ printk("elf_core_dump: %d segs %lu limit\n", segs, limit);
#endif
/* Set up header */
@@ -1294,13 +1280,10 @@
dataoff = offset = roundup(offset, ELF_EXEC_PAGESIZE);
/* Write program headers for segments dump */
- for(vma = current->mm->mmap, i = 0;
- i < segs && vma != NULL; vma = vma->vm_next) {
+ for(vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
struct elf_phdr phdr;
size_t sz;
- i++;
-
sz = vma->vm_end - vma->vm_start;
phdr.p_type = PT_LOAD;
@@ -1326,19 +1309,36 @@
DUMP_SEEK(dataoff);
- for(i = 0, vma = current->mm->mmap;
- i < segs && vma != NULL;
- vma = vma->vm_next) {
- unsigned long addr = vma->vm_start;
- unsigned long len = vma->vm_end - vma->vm_start;
+ for(vma = current->mm->mmap; vma != NULL; vma = vma->vm_next) {
+ unsigned long addr;
- i++;
if (!maydump(vma))
continue;
#ifdef DEBUG
printk("elf_core_dump: writing %08lx %lx\n", addr, len);
#endif
- DUMP_WRITE((void *)addr, len);
+ for (addr = vma->vm_start;
+ addr < vma->vm_end;
+ addr += PAGE_SIZE) {
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ pgd = pgd_offset(vma->vm_mm, addr);
+ pmd = pmd_alloc(pgd, addr);
+
+ if (!pmd)
+ goto end_coredump;
+ pte = pte_alloc(pmd, addr);
+ if (!pte)
+ goto end_coredump;
+ if (!pte_present(*pte) &&
+ pte_none(*pte)) {
+ DUMP_SEEK (file->f_pos + PAGE_SIZE);
+ } else {
+ DUMP_WRITE((void*)addr, PAGE_SIZE);
+ }
+ }
}
if ((off_t) file->f_pos != offset) {