Re: [PATCH stable 4.9-5.15] mm: Fix TLB flush for not-first PFNMAP mappings in unmap_region()

On Thu, Sep 15, 2022 at 04:25:19PM +0200, Jann Horn wrote:

This is a stable-specific patch. I botched the stable-specific rewrite of commit b67fbebd4cf98 ("mmu_gather: Force tlb-flush VM_PFNMAP vmas"): As Hugh pointed out, unmap_region() actually operates on a list of VMAs, and the variable "vma" merely points to the first VMA in that list. So if we want to check whether any of the VMAs we're operating on is PFNMAP or MIXEDMAP, we have to iterate through the list and check each VMA.

Signed-off-by: Jann Horn jannh@google.com

mm/mmap.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)

Now queued up everywhere, thanks.

greg k-h