[v5,0/1] KVM: s390: fix a newly introduced bug

Message

Claudio Imbrenda March 12, 2025, 6:49 p.m. UTC

Fix race when making a page secure (hold pte lock again)

This should fix the issues I have seen, which I think/hope are also the same
issues that David found.

v4->v5:
* fixed kerneldoc for s390_wiggle_split_folio()
* remove get_locked_valid_pte() and replace it with folio_walk_start()
  [thanks David]

v3->v4:
* move and rename s390_wiggle_split_folio() to fix a compile issue when
  KVM is not selected
* removed obsolete reference to __() from comments

v2->v3:
* added check for pte_write() in make_hva_secure() [thanks David]

v1->v2:
* major refactoring
* walk the page tables only once
* when importing, manually fault in pages if needed

Claudio Imbrenda (1):
  KVM: s390: pv: fix race when making a page secure

 arch/s390/include/asm/gmap.h |   1 -
 arch/s390/include/asm/uv.h   |   2 +-
 arch/s390/kernel/uv.c        | 136 +++++++++++++++++++++++++++++++++--
 arch/s390/kvm/gmap.c         | 103 ++------------------------
 arch/s390/kvm/kvm-s390.c     |  25 ++++---
 arch/s390/mm/gmap.c          |  28 --------
 6 files changed, 151 insertions(+), 144 deletions(-)