Merge tag 'kvm-x86-coco-7.4' of https://github.com/kvm-x86/linux into HEAD

KVM guest_memfd and CoCo changes for 7.4

 - Take the invalidate lock when unbinding a dying file to fix a race with
   kvm_gmem_invalidate_end() that results in KVM leaving the MMU invalidation
   count elevated.  Not taking the lock in the first place was pure misguided
   paranoid.

 - When binding a memslot, purge the bindings if storing the new memslot fails,
   as Xarray's "store range" API can subtly fail partway through.

 - Establish memslot<=>guest_memfd bindings *after* the memslot is ready, as
   the memslot becomes reachable the instant the binding is installed.

 - Don't grab a page refcount when reloading an SNP VMSA and stop returning a
   "struct page" from guest_memfd's PFN lookup altogether, to ensure that KVM
   doesn't hold any unnecessary refcounts (the lifetime of the page is ensured
   by MMU notifiers and similar hooks).  Preventing unnecessary refcounts
   greatly simplifies supporting in-place SHARED=>PRIVATE conversions.

 - Add support for in-place PRIVATE<=>SHARED conversion, i.e. allow a single
   guest_memfd instance to be used for both PRIVATE and SHARED variations of
   CoCo guests' memory (though not at the same time).  This eliminates the need
   to double allocate guest memory for TDX and SNP, and is basically a hard
   requirement for pKVM, which relies on being able to preserve memory contents
   on conversions.

 - Hack-a-fix a deadlock bug in ->error_remove_folio() by returning -EBUSY if
   the filemap invalidate lock is contended.  Punt on a proper fix for the
   moment, as a proper fix likely involves reworking truncate_error_folio().

 - Add a pile of selftests for in-place conversions.

 - Misc guest_memfd cleanups

Conflicts in arch/arm64/kvm/mmu.c: convert to use s2vi.

0 files changed, 0 insertions, 0 deletions