[PATCH v3 00/12] KVM: x86/mmu: Clean up MMU_DEBUG and BUG/WARN usage

From: Sean Christopherson
Date: Fri Jul 28 2023 - 20:49:07 EST


This series consist of three loosely related miniseries:

1. Remove the noisy prints buried behind MMU_DEBUG, and replace MMU_DEBUG
with a KVM_PROVE_MMU Kconfig.

2. Use WARN_ON_ONCE() for all runtime WARNs, i.e. avoid spamming the
kernel log if something goes awry in the MMU.

3. Demote BUG() usage in the shadow MMU to KVM_BUG_ON() when the kernel
is built with CONFIG_BUG_ON_DATA_CORRUPTION=n.

v3:
- Fix build errors related to is_empty_shadow_page (which the bot has
told me about several times, and I managed to forget every other
time...) [kernel test robot]

v2:
- https://lore.kernel.org/all/20230721230006.2337941-1-seanjc@xxxxxxxxxx
- Collect a review. [Mingwei]
- Call out the more obvious path to FNAME(walk_addr_generic) in patch 6. [David]
- Use BUILD_BUG_ON_INVALID() for the stub. [David]

v1: https://lore.kernel.org/all/20230511235917.639770-1-seanjc@xxxxxxxxxx

Mingwei Zhang (1):
KVM: x86/mmu: Plumb "struct kvm" all the way to pte_list_remove()

Sean Christopherson (11):
KVM: x86/mmu: Delete pgprintk() and all its usage
KVM: x86/mmu: Delete rmap_printk() and all its usage
KVM: x86/mmu: Delete the "dbg" module param
KVM: x86/mmu: Avoid pointer arithmetic when iterating over SPTEs
KVM: x86/mmu: Cleanup sanity check of SPTEs at SP free
KVM: x86/mmu: Rename MMU_WARN_ON() to KVM_MMU_WARN_ON()
KVM: x86/mmu: Convert "runtime" WARN_ON() assertions to WARN_ON_ONCE()
KVM: x86/mmu: Bug the VM if a vCPU ends up in long mode without PAE
enabled
KVM: x86/mmu: Replace MMU_DEBUG with proper KVM_PROVE_MMU Kconfig
KVM: x86/mmu: Use BUILD_BUG_ON_INVALID() for KVM_MMU_WARN_ON() stub
KVM: x86/mmu: BUG() in rmap helpers iff
CONFIG_BUG_ON_DATA_CORRUPTION=y

arch/x86/kvm/Kconfig | 13 +++
arch/x86/kvm/mmu/mmu.c | 163 +++++++++++++-------------------
arch/x86/kvm/mmu/mmu_internal.h | 14 +--
arch/x86/kvm/mmu/page_track.c | 16 ++--
arch/x86/kvm/mmu/paging_tmpl.h | 23 +++--
arch/x86/kvm/mmu/spte.c | 6 +-
arch/x86/kvm/mmu/spte.h | 8 +-
arch/x86/kvm/mmu/tdp_iter.c | 4 +-
arch/x86/kvm/mmu/tdp_mmu.c | 28 +++---
include/linux/kvm_host.h | 19 ++++
10 files changed, 143 insertions(+), 151 deletions(-)


base-commit: fdf0eaf11452d72945af31804e2a1048ee1b574c
--
2.41.0.487.g6d72f3e995-goog