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

Joerg Roedel
2019-07-19T18:47:04Z

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(-)

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2.17.1