[PATCH v3 00/16] KVM: x86: Always use non-compat vcpu_runstate_info size for gfn=>pfn cache
From: Paolo Bonzini
Date: Thu Oct 27 2022 - 12:19:31 EST
The highlights are two fixes for bugs where "destroying" and "initializing"
a gfn=>pfn cache while it is being accessed results in various forms of
badness, e.g. re-initialization of an in-use lock, consuming a NULL pointer,
potential memory corruption, etc...
Everything else is cleanup to make the gpc APIs easier to use and harder
to use incorrectly.
The main difference with v2 is in playing it safer with 32-bit guests that
place the runstate info close to the end of a page. This is a preexisting
issue that is fixed here because it affects the gfn-to-pfn cache API.
In particular, compared to v2 the length is passed at activation time
instead of initialization time. This affects patch 7 ("KVM: Store
gfn_to_pfn_cache length at activation time"), which now incorporates some
parts of patch 13 ("KVM: Drop @gpa from exported gfn=>pfn cache check()
and refresh() helpers") to introduce __kvm_gpc_refresh.
Initially I wanted to restrict the ordering between setting Xen VM
and vCPU attributes. In the end I left that patch out because it may
complicate the reset sequence further.
Paolo
Michal Luczaj (8):
KVM: Initialize gfn_to_pfn_cache locks in dedicated helper
KVM: Shorten gfn_to_pfn_cache function names
KVM: x86: Remove unused argument in gpc_unmap_khva()
KVM: Store immutable gfn_to_pfn_cache properties
KVM: Use gfn_to_pfn_cache's immutable "kvm" in kvm_gpc_check()
KVM: Clean up hva_to_pfn_retry()
KVM: Use gfn_to_pfn_cache's immutable "kvm" in kvm_gpc_refresh()
KVM: selftests: Add tests in xen_shinfo_test to detect lock races
Paolo Bonzini (2):
KVM: x86: set gfn-to-pfn cache length consistently with VM word size
KVM: Store gfn_to_pfn_cache length at activation time
Sean Christopherson (6):
KVM: Reject attempts to consume or refresh inactive gfn_to_pfn_cache
KVM: Drop KVM's API to allow temprorarily unmapping gfn=>pfn cache
KVM: Do not partially reinitialize gfn=>pfn cache during activation
KVM: Drop @gpa from exported gfn=>pfn cache check() and refresh()
helpers
KVM: Skip unnecessary "unmap" if gpc is already valid during refresh
KVM: selftests: Mark "guest_saw_irq" as volatile in xen_shinfo_test
arch/x86/kvm/x86.c | 24 +--
arch/x86/kvm/xen.c | 121 ++++++++------
include/linux/kvm_host.h | 70 ++++----
include/linux/kvm_types.h | 2 +
.../selftests/kvm/x86_64/xen_shinfo_test.c | 142 +++++++++++++++-
virt/kvm/pfncache.c | 155 ++++++++++--------
6 files changed, 345 insertions(+), 169 deletions(-)
--
2.31.1