[0/3,v3] Sync unmappings in vmalloc/ioremap areas

Message

Joerg Roedel July 19, 2019, 6:46 p.m. UTC

Hi,

here is a small patch-set to sync unmappings in the
vmalloc/ioremap areas between page-tables in the system.

This is only needed x86-32 with !SHARED_KERNEL_PMD, which is
the case on a PAE kernel with PTI enabled.

On affected systems the missing sync causes old mappings to
persist in some page-tables, causing data corruption and
other undefined behavior.

Please review.

Thanks,

	Joerg

Changes v2 -> v3:

	- Moved the vmalloc_sync_all() call to the lazy vmap
	  purge function as requested by Andy Lutomirski

	- Made sure that the code in vmalloc_sync_all()
	  really iterates over all pgds (pointed out by
	  Thomas Gleixner)

	- Added a couple of comments

Changes v1 -> v2:
 
	- Added correct Fixes-tags to all patches

Joerg Roedel (3):
  x86/mm: Check for pfn instead of page in vmalloc_sync_one()
  x86/mm: Sync also unmappings in vmalloc_sync_all()
  mm/vmalloc: Sync unmappings in vunmap_page_range()

 arch/x86/mm/fault.c | 15 ++++++---------
 mm/vmalloc.c        |  9 +++++++++
 2 files changed, 15 insertions(+), 9 deletions(-)