Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 62ec0d8c authored by Dave Jiang's avatar Dave Jiang Committed by Linus Torvalds
Browse files

mm: fix BUG_ON() in vmf_insert_pfn_pud() from VM_MIXEDMAP removal 

It looks like I missed the PUD path when doing VM_MIXEDMAP removal.
This can be triggered by:
1. Boot with memmap=4G!8G
2. build ndctl with destructive flag on
3. make TESTS=device-dax check

[  +0.000675] kernel BUG at mm/huge_memory.c:824!

Applying the same change that was applied to vmf_insert_pfn_pmd() in the
original patch.

Link: http://lkml.kernel.org/r/153565957352.35524.1005746906902065126.stgit@djiang5-desk3.ch.intel.com


Fixes: e1fb4a08 ("dax: remove VM_MIXEDMAP for fsdax and device dax")
Signed-off-by: default avatarDave Jiang <dave.jiang@intel.com>
Reported-by: default avatarVishal Verma <vishal.l.verma@intel.com>
Tested-by: default avatarVishal Verma <vishal.l.verma@intel.com>
Acked-by: default avatarJeff Moyer <jmoyer@redhat.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 8a2336e5

mm/huge_memory.c

+2 −2
Original line number Diff line number Diff line
@@ -821,11 +821,11 @@ vm_fault_t vmf_insert_pfn_pud(struct vm_area_struct *vma, unsigned long addr, 
	 * but we need to be consistent with PTEs and architectures that

	 * can't support a 'special' bit.

	 */

	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)));

	BUG_ON(!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) &&

			!pfn_t_devmap(pfn));

	BUG_ON((vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)) ==

						(VM_PFNMAP|VM_MIXEDMAP));

	BUG_ON((vma->vm_flags & VM_PFNMAP) && is_cow_mapping(vma->vm_flags));

	BUG_ON(!pfn_t_devmap(pfn));



	if (addr < vma->vm_start || addr >= vma->vm_end)

		return VM_FAULT_SIGBUS;