[PATCH v3 00/10] KVM: s390: Misc fixes

From: Claudio Imbrenda

Date: Mon Jul 27 2026 - 11:26:29 EST


Fix a bunch of small issues that came up during the previous round of fixes.

They are mostly extremely unlikely races, but they should be fixed
nonetheless.

v2->v3
* Use READ_ONCE to pair with WRITE_ONCE in the first patch
* Fix leaking PGM_ADDRESSING also in kvm_s390_keyop() and related functions
* Fix and improve commit messages
* Use slots_arch_lock instead of slots_lock for ESSA operations
* Use normal spin_{,un}lock() functions instead of scoped_guard to avoid
mixing the two styles
* Use the newly introduced vcpu->arch.initialized to determine whether the
SCA entry needs to be cleared
* Improve handling of -EINTR; handle_mvpg_pei() needed some refactoring to
deal with it properly
* Three new patches:
- Free the mmu cache when kvm_arch_vcpu_create() fails
- Fix ordering when adding to SCA
- Fix cleanup in kvm_s390_pv_create_cpu()

v1->v2
* Drop some patches that have been picked upstream in the meantime.
* Drop patch 3, as it was trying to fix a bug that does not exist
* Avoid the NULL gmap dereference by using a flag
* Fix the return value of kvm_s390_[gp]et_skeys too
* Use kvm->slots_arch_lock instead of kvm->slots_lock for CMMA and ESSA
handling, to avoid potential deadlocks with the RCU.
* Three new patches to fix other issues that came out while fixing the
other issues

Claudio Imbrenda (10):
KVM: s390: Fix unlikely NULL gmap dereference
KVM: s390: Fix leaking of PGM_ADDRESSING to userspace
KVM: s390: Fix race in __do_essa()
KVM: s390: cmma: Fix dirty tracking when removing memslot
KVM: s390: ucontrol: Add missing locking around gmap_remove_child()
KVM: s390: Fix overclearing ESCA in case of error
KVM: s390: Return -EINTR if a signal was pending while faulting-in
KVM: s390: Free the mmu cache when kvm_arch_vcpu_create() fails
KVM: s390: Fix ordering when adding to SCA
KVM: s390: Fix cleanup in kvm_s390_pv_create_cpu()

arch/s390/include/asm/kvm_host.h | 1 +
arch/s390/kvm/dat.c | 23 ++++++----
arch/s390/kvm/dat.h | 2 +-
arch/s390/kvm/faultin.c | 4 +-
arch/s390/kvm/intercept.c | 18 ++++----
arch/s390/kvm/interrupt.c | 2 +-
arch/s390/kvm/kvm-s390.c | 72 ++++++++++++++++++++++----------
arch/s390/kvm/priv.c | 10 +++--
arch/s390/kvm/pv.c | 43 +++++++++----------
9 files changed, 106 insertions(+), 69 deletions(-)

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2.55.0