On Tue 07-11-17 15:20:29, Abdul Haleem wrote:
> Hi,
>
> Today's next kernel fails to boot on Power 7 Machine with below errors
> in boot log messages.
>
> 'Uhuuh, elf segement at 0000000010040000 requested but the memory is
> mapped already'
>
> It was introduced with commit:
>
> 0692229e : fs/binfmt_elf.c: drop MAP_FIXED usage from elf_map
Weird. Clashes shouldn't really happen. Maybe power is doing something
different from other platforms. Could you apply the following debugging
patch to see what is going on there?
---
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 0abc30d681ae..f098aaf60039 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -361,8 +361,28 @@ static unsigned long elf_vm_mmap(struct file *filep,
unsigned long addr,
return map_addr;
if ((type & MAP_FIXED) && map_addr != addr) {
- pr_info("Uhuuh, elf segement at %p requested but the memory is
mapped already\n",
- (void*)addr);
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ pr_info("Uhuuh, elf segement at %p requested but the memory is
mapped already, got %p\n",
+ (void*)addr, (void*)map_addr);
+ down_read(&mm->mmap_sem);
+ vma = find_vma(mm, addr);
+ if (vma) {
+ const char *name;
+ pr_info("Clashing vma [%lx, %lx] flags:%lx",
vma->vm_start, vma->vm_end, vma->vm_flags);
+ name = arch_vma_name(vma);
+ if (!name) {
+ if (vma->vm_start <= mm->brk &&
+ vma->vm_end >= mm->start_brk)
+ name = "[heap]";
+ else if (vma->vm_start <=
vma->vm_mm->start_stack &&
+ vma->vm_end >=
vma->vm_mm->start_stack)
+ name = "[stack]";
+ }
+ pr_cont(" name:%s\n", name);
+ } else
+ pr_info("Uhm, no clashing VMA\n");
+ up_read(&mm->mmap_sem);
return -EAGAIN;
}
--
Michal Hocko
SUSE Labs
