Re: [parisc-linux] Re: Problems with kernel mmap (failingtst-mmap-eofsync in glibc on parisc)
From: James Bottomley
Date: Sat Aug 23 2003 - 13:47:33 EST
On Sat, 2003-08-23 at 02:22, Hugh Dickins wrote:
> Good idea. It's VM_MAYSHARE you need to check for.
OK, to get all this to work, there's a corner case in do_mremap() that I
need to be fixed:
When choosing the flags for the new area, it keys off VM_SHARED to
determine whether MAP_SHARED is passed to the mapping. It has to key of
VM_MAYSHARE to preserve VM_MAYSHARE on the new mapping.
Patch below.
James
===== mremap.c 1.32 vs edited =====
--- 1.32/mm/mremap.c Thu Aug 7 12:29:10 2003
+++ edited/mremap.c Sat Aug 23 10:54:21 2003
@@ -420,7 +420,7 @@
if (flags & MREMAP_MAYMOVE) {
if (!(flags & MREMAP_FIXED)) {
unsigned long map_flags = 0;
- if (vma->vm_flags & VM_SHARED)
+ if (vma->vm_flags & VM_MAYSHARE)
map_flags |= MAP_SHARED;
new_addr = get_unmapped_area(vma->vm_file, 0, new_len,