linux_dsm_epyc7002/arch/x86/kvm
Ben Gardon c3cf9ffe8d KVM: x86/mmu: Ensure TDP MMU roots are freed after yield
commit a889ea54b3daa63ee1463dc19ed699407d61458b upstream.

Many TDP MMU functions which need to perform some action on all TDP MMU
roots hold a reference on that root so that they can safely drop the MMU
lock in order to yield to other threads. However, when releasing the
reference on the root, there is a bug: the root will not be freed even
if its reference count (root_count) is reduced to 0.

To simplify acquiring and releasing references on TDP MMU root pages, and
to ensure that these roots are properly freed, move the get/put operations
into another TDP MMU root iterator macro.

Moving the get/put operations into an iterator macro also helps
simplify control flow when a root does need to be freed. Note that using
the list_for_each_entry_safe macro would not have been appropriate in
this situation because it could keep a pointer to the next root across
an MMU lock release + reacquire, during which time that root could be
freed.

Reported-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Fixes: faaf05b00a ("kvm: x86/mmu: Support zapping SPTEs in the TDP MMU")
Fixes: 063afacd87 ("kvm: x86/mmu: Support invalidate range MMU notifier for TDP MMU")
Fixes: a6a0b05da9 ("kvm: x86/mmu: Support dirty logging for the TDP MMU")
Fixes: 1488199856 ("kvm: x86/mmu: Support disabling dirty logging for the tdp MMU")
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20210107001935.3732070-1-bgardon@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-12 20:18:22 +01:00
..
mmu KVM: x86/mmu: Ensure TDP MMU roots are freed after yield 2021-01-12 20:18:22 +01:00
svm KVM: SVM: Remove the call to sev_platform_status() during setup 2020-12-30 11:54:14 +01:00
vmx KVM: x86: reinstate vendor-agnostic check on SPEC_CTRL cpuid bits 2020-12-30 11:54:14 +01:00
cpuid.c Fixes for ARM and x86, the latter especially for old processors 2020-11-15 09:57:58 -08:00
cpuid.h KVM: x86: reinstate vendor-agnostic check on SPEC_CTRL cpuid bits 2020-12-30 11:54:14 +01:00
debugfs.c KVM: let kvm_destroy_vm_debugfs clean up vCPU debugfs directories 2020-06-04 11:00:54 -04:00
emulate.c KVM: x86: clflushopt should be treated as a no-op by emulation 2020-11-13 06:28:33 -05:00
hyperv.c ARM: 2020-10-23 11:17:56 -07:00
hyperv.h x86/kvm/hyper-v: Add support for synthetic debugger interface 2020-06-01 04:26:11 -04:00
i8254.c kvm: i8254: remove redundant assignment to pointer s 2020-06-11 12:35:18 -04:00
i8254.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
i8259.c KVM: x86: Refactor picdev_write() to prevent Spectre-v1/L1TF attacks 2020-01-27 19:59:37 +01:00
ioapic.c KVM: ioapic: break infinite recursion on lazy EOI 2020-10-24 04:42:06 -04:00
ioapic.h kvm/x86: Remove redundant function implementations 2020-05-27 13:11:10 -04:00
irq_comm.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
irq.c KVM: x86: Fix split-irqchip vs interrupt injection window request 2020-11-27 09:27:28 -05:00
irq.h kvm/x86: Remove redundant function implementations 2020-05-27 13:11:10 -04:00
Kconfig x86/kvm: hide KVM options from menuconfig when KVM is not compiled 2020-10-21 17:36:30 -04:00
kvm_cache_regs.h KVM: x86: Let the guest own CR4.FSGSBASE 2020-10-21 17:48:50 -04:00
kvm_emulate.h ARM: 2020-04-02 15:13:15 -07:00
lapic.c KVM: x86: handle !lapic_in_kernel case in kvm_cpu_*_extint 2020-11-27 09:19:52 -05:00
lapic.h KVM: nVMX: Morph notification vector IRQ on nested VM-Enter to pending PI 2020-09-28 07:57:22 -04:00
Makefile kvm: x86/mmu: Init / Uninit the TDP MMU 2020-10-21 18:17:00 -04:00
mmu.h KVM: x86: Move illegal GPA helper out of the MMU code 2020-09-28 07:57:27 -04:00
mtrr.c KVM: x86: Protect MSR-based index computations in fixed_msr_to_seg_unit() from Spectre-v1/L1TF attacks 2020-01-27 19:59:39 +01:00
pmu.c KVM/x86: pmu: Fix #GP condition check for RDPMC emulation 2020-07-09 07:08:37 -04:00
pmu.h kvm: x86: limit the maximum number of vPMU fixed counters to 3 2020-07-08 16:21:59 -04:00
trace.h KVM: x86: Use common definition for kvm_nested_vmexit tracepoint 2020-09-28 07:57:52 -04:00
tss.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
x86.c KVM: x86: Fix split-irqchip vs interrupt injection window request 2020-11-27 09:27:28 -05:00
x86.h KVM: x86: use positive error values for msr emulation that causes #GP 2020-11-08 04:41:28 -05:00