From 83e9b7e929d1323b9a155d186f77aa8c06155cc3 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Mon, 21 Nov 2005 21:32:12 -0800 Subject: [PATCH] unpaged: private write VM_RESERVED The PageReserved removal in 2.6.15-rc1 issued a "deprecated" message when you tried to mmap or mprotect MAP_PRIVATE PROT_WRITE a VM_RESERVED, and failed with -EACCES: because do_wp_page lacks the refinement to COW pages in those areas, nor do we expect to find anonymous pages in them; and it seemed just bloat to add code for handling such a peculiar case. But immediately it caused vbetool and ddcprobe (using lrmi) to fail. So revert the "deprecated" messages, letting mmap and mprotect succeed. But leave do_wp_page's BUG_ON(vma->vm_flags & VM_RESERVED) in place until we've added the code to do it right: so this particular patch is only good if the app doesn't really need to write to that private area. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/mmap.c | 11 ----------- 1 file changed, 11 deletions(-) (limited to 'mm/mmap.c') diff --git a/mm/mmap.c b/mm/mmap.c index 4f8def03428c..11ca5927d5ff 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1076,17 +1076,6 @@ munmap_back: error = file->f_op->mmap(file, vma); if (error) goto unmap_and_free_vma; - if ((vma->vm_flags & (VM_SHARED | VM_WRITE | VM_RESERVED)) - == (VM_WRITE | VM_RESERVED)) { - printk(KERN_WARNING "program %s is using MAP_PRIVATE, " - "PROT_WRITE mmap of VM_RESERVED memory, which " - "is deprecated. Please report this to " - "linux-kernel@vger.kernel.org\n",current->comm); - if (vma->vm_ops && vma->vm_ops->close) - vma->vm_ops->close(vma); - error = -EACCES; - goto unmap_and_free_vma; - } } else if (vm_flags & VM_SHARED) { error = shmem_zero_setup(vma); if (error) -- cgit v1.2.3-58-ga151