[PATCH 00/13] KVM: guest_memfd fixes

Sean Christopherson
2023-09-21T21:08:23Z

Fix a variety of bugs in the guest_memfd series, almost all of which are
my fault, and add assertions and testcases to detect future regressions.

The last patch, renaming guest_mem.c to guest_memfd.c, is obviously not a
bug fix, I included it here so that if we want to go with guest_memfd.c,
squashing everything will be straightforward.

Note, the truncate fix and test conflicts with Isaku's series[*]. My
fix is more correct (knock wood), and my test is slightly more comprehensive
(though arguably not really all that more interesting).

Note #2, this is based on kvm-x86/guest_memfd, to which I force-pushed v12.

Note #3, the patches are organized so that they can be squashed with their
Fixes, i.e. the splits are more than a bit odd in some places.

[*] https://lore.kernel.org/all/cover.1695327124.git.isaku.yamahata@intel.com

Sean Christopherson (13):
KVM: Assert that mmu_invalidate_in_progress *never* goes negative
KVM: Actually truncate the inode when doing PUNCH_HOLE for guest_memfd
KVM: WARN if *any* MMU invalidation sequence doesn't add a range
KVM: WARN if there are danging MMU invalidations at VM destruction
KVM: Fix MMU invalidation bookkeeping in guest_memfd
KVM: Disallow hugepages for incompatible gmem bindings, but let 'em
succeed
KVM: x86/mmu: Track PRIVATE impact on hugepage mappings for all
memslots
KVM: x86/mmu: Zap shared-only memslots when private attribute changes
KVM: Always add relevant ranges to invalidation set when changing
attributes
KVM: x86/mmu: Drop repeated add() of to-be-invalidated range
KVM: selftests: Refactor private mem conversions to prep for
punch_hole test
KVM: selftests: Add a "pure" PUNCH_HOLE on guest_memfd testcase
KVM: Rename guest_mem.c to guest_memfd.c

arch/x86/kvm/mmu/mmu.c | 25 ++--
.../kvm/x86_64/private_mem_conversions_test.c | 112 ++++++++++++++----
virt/kvm/Makefile.kvm | 2 +-
virt/kvm/{guest_mem.c => guest_memfd.c} | 84 +++++++------
virt/kvm/kvm_main.c | 40 +++++--
5 files changed, 184 insertions(+), 79 deletions(-)
rename virt/kvm/{guest_mem.c => guest_memfd.c} (92%)

base-commit: 7af66fbd6d89b159acc359895449b5940b6e4fdb
--
2.42.0.515.g380fc7ccd1-goog