commit 8d5678a766 upstream.
Before Commit c3e5e415bc ("KVM: X86: Change kvm_sync_page()
to return true when remote flush is needed"), the return value
of kvm_sync_page() indicates whether the page is synced, and
kvm_mmu_get_page() would rebuild page when the sync fails.
But now, kvm_sync_page() returns false when the page is
synced and no tlb flushing is required, which leads to
rebuild page in kvm_mmu_get_page(). So return the return
value of mmu->sync_page() directly and check it in
kvm_mmu_get_page(). If the sync fails, the page will be
zapped and the invalid_list is not empty, so set flush as
true is accepted in mmu_sync_children().
Cc: stable@vger.kernel.org
Fixes: c3e5e415bc ("KVM: X86: Change kvm_sync_page() to return true when remote flush is needed")
Signed-off-by: Hou Wenlong <houwenlong.hwl@antgroup.com>
Acked-by: Lai Jiangshan <jiangshanlai@gmail.com>
Message-Id: <0dabeeb789f57b0d793f85d073893063e692032d.1647336064.git.houwenlong.hwl@antgroup.com>
[mmu_sync_children should not flush if the page is zapped. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f122dfe447 upstream.
Use the recently introduced __try_cmpxchg_user() to update guest PTE A/D
bits instead of mapping the PTE into kernel address space. The VM_PFNMAP
path is broken as it assumes that vm_pgoff is the base pfn of the mapped
VMA range, which is conceptually wrong as vm_pgoff is the offset relative
to the file and has nothing to do with the pfn. The horrific hack worked
for the original use case (backing guest memory with /dev/mem), but leads
to accessing "random" pfns for pretty much any other VM_PFNMAP case.
Fixes: bd53cb35a3 ("X86/KVM: Handle PFNs outside of kernel reach when touching GPTEs")
Debugged-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Tested-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Reported-by: syzbot+6cde2282daa792c49ab8@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220202004945.2540433-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 9f46c187e2 upstream.
With shadow paging enabled, the INVPCID instruction results in a call
to kvm_mmu_invpcid_gva. If INVPCID is executed with CR0.PG=0, the
invlpg callback is not set and the result is a NULL pointer dereference.
Fix it trivially by checking for mmu->invlpg before every call.
There are other possibilities:
- check for CR0.PG, because KVM (like all Intel processors after P5)
flushes guest TLB on CR0.PG changes so that INVPCID/INVLPG are a
nop with paging disabled
- check for EFER.LMA, because KVM syncs and flushes when switching
MMU contexts outside of 64-bit mode
All of these are tricky, go for the simple solution. This is CVE-2022-1789.
Reported-by: Yongkang Jia <kangel@zju.edu.cn>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
[fix conflict due to missing b9e5603c2a]
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit b28cb0cd2c upstream.
When zapping obsolete pages, update the running count of zapped pages
regardless of whether or not the list has become unstable due to zapping
a shadow page with its own child shadow pages. If the VM is backed by
mostly 4kb pages, KVM can zap an absurd number of SPTEs without bumping
the batch count and thus without yielding. In the worst case scenario,
this can cause a soft lokcup.
watchdog: BUG: soft lockup - CPU#12 stuck for 22s! [dirty_log_perf_:13020]
RIP: 0010:workingset_activation+0x19/0x130
mark_page_accessed+0x266/0x2e0
kvm_set_pfn_accessed+0x31/0x40
mmu_spte_clear_track_bits+0x136/0x1c0
drop_spte+0x1a/0xc0
mmu_page_zap_pte+0xef/0x120
__kvm_mmu_prepare_zap_page+0x205/0x5e0
kvm_mmu_zap_all_fast+0xd7/0x190
kvm_mmu_invalidate_zap_pages_in_memslot+0xe/0x10
kvm_page_track_flush_slot+0x5c/0x80
kvm_arch_flush_shadow_memslot+0xe/0x10
kvm_set_memslot+0x1a8/0x5d0
__kvm_set_memory_region+0x337/0x590
kvm_vm_ioctl+0xb08/0x1040
Fixes: fbb158cb88 ("KVM: x86/mmu: Revert "Revert "KVM: MMU: zap pages in batch""")
Reported-by: David Matlack <dmatlack@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220511145122.3133334-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9191b8f074 ]
WARN and bail if KVM attempts to free a root that isn't backed by a shadow
page. KVM allocates a bare page for "special" roots, e.g. when using PAE
paging or shadowing 2/3/4-level page tables with 4/5-level, and so root_hpa
will be valid but won't be backed by a shadow page. It's all too easy to
blindly call mmu_free_root_page() on root_hpa, be nice and WARN instead of
crashing KVM and possibly the kernel.
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1d0e848060 upstream.
Resolve nx_huge_pages to true/false when kvm.ko is loaded, leaving it as
-1 is technically undefined behavior when its value is read out by
param_get_bool(), as boolean values are supposed to be '0' or '1'.
Alternatively, KVM could define a custom getter for the param, but the
auto value doesn't depend on the vendor module in any way, and printing
"auto" would be unnecessarily unfriendly to the user.
In addition to fixing the undefined behavior, resolving the auto value
also fixes the scenario where the auto value resolves to N and no vendor
module is loaded. Previously, -1 would result in Y being printed even
though KVM would ultimately disable the mitigation.
Rename the existing MMU module init/exit helpers to clarify that they're
invoked with respect to the vendor module, and add comments to document
why KVM has two separate "module init" flows.
=========================================================================
UBSAN: invalid-load in kernel/params.c:320:33
load of value 255 is not a valid value for type '_Bool'
CPU: 6 PID: 892 Comm: tail Not tainted 5.17.0-rc3+ #799
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
<TASK>
dump_stack_lvl+0x34/0x44
ubsan_epilogue+0x5/0x40
__ubsan_handle_load_invalid_value.cold+0x43/0x48
param_get_bool.cold+0xf/0x14
param_attr_show+0x55/0x80
module_attr_show+0x1c/0x30
sysfs_kf_seq_show+0x93/0xc0
seq_read_iter+0x11c/0x450
new_sync_read+0x11b/0x1a0
vfs_read+0xf0/0x190
ksys_read+0x5f/0xe0
do_syscall_64+0x3b/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
</TASK>
=========================================================================
Fixes: b8e8c8303f ("kvm: mmu: ITLB_MULTIHIT mitigation")
Cc: stable@vger.kernel.org
Reported-by: Bruno Goncalves <bgoncalv@redhat.com>
Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220331221359.3912754-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 2a8859f373 upstream.
FNAME(cmpxchg_gpte) is an inefficient mess. It is at least decent if it
can go through get_user_pages_fast(), but if it cannot then it tries to
use memremap(); that is not just terribly slow, it is also wrong because
it assumes that the VM_PFNMAP VMA is contiguous.
The right way to do it would be to do the same thing as
hva_to_pfn_remapped() does since commit add6a0cd1c ("KVM: MMU: try to
fix up page faults before giving up", 2016-07-05), using follow_pte()
and fixup_user_fault() to determine the correct address to use for
memremap(). To do this, one could for example extract hva_to_pfn()
for use outside virt/kvm/kvm_main.c. But really there is no reason to
do that either, because there is already a perfectly valid address to
do the cmpxchg() on, only it is a userspace address. That means doing
user_access_begin()/user_access_end() and writing the code in assembly
to handle exceptions correctly. Worse, the guest PTE can be 8-byte
even on i686 so there is the extra complication of using cmpxchg8b to
account for. But at least it is an efficient mess.
(Thanks to Linus for suggesting improvement on the inline assembly).
Reported-by: Qiuhao Li <qiuhao@sysec.org>
Reported-by: Gaoning Pan <pgn@zju.edu.cn>
Reported-by: Yongkang Jia <kangel@zju.edu.cn>
Reported-by: syzbot+6cde2282daa792c49ab8@syzkaller.appspotmail.com
Debugged-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Tested-by: Maxim Levitsky <mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Fixes: bd53cb35a3 ("X86/KVM: Handle PFNs outside of kernel reach when touching GPTEs")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 3354ef5a59 upstream.
Explicitly check for present SPTEs when clearing dirty bits in the TDP
MMU. This isn't strictly required for correctness, as setting the dirty
bit in a defunct SPTE will not change the SPTE from !PRESENT to PRESENT.
However, the guarded MMU_WARN_ON() in spte_ad_need_write_protect() would
complain if anyone actually turned on KVM's MMU debugging.
Fixes: a6a0b05da9 ("kvm: x86/mmu: Support dirty logging for the TDP MMU")
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Message-Id: <20220226001546.360188-3-seanjc@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d62007edf0 upstream.
Zap both valid and invalid roots when zapping/unmapping a gfn range, as
KVM must ensure it holds no references to the freed page after returning
from the unmap operation. Most notably, the TDP MMU doesn't zap invalid
roots in mmu_notifier callbacks. This leads to use-after-free and other
issues if the mmu_notifier runs to completion while an invalid root
zapper yields as KVM fails to honor the requirement that there must be
_no_ references to the page after the mmu_notifier returns.
The bug is most easily reproduced by hacking KVM to cause a collision
between set_nx_huge_pages() and kvm_mmu_notifier_release(), but the bug
exists between kvm_mmu_notifier_invalidate_range_start() and memslot
updates as well. Invalidating a root ensures pages aren't accessible by
the guest, and KVM won't read or write page data itself, but KVM will
trigger e.g. kvm_set_pfn_dirty() when zapping SPTEs, and thus completing
a zap of an invalid root _after_ the mmu_notifier returns is fatal.
WARNING: CPU: 24 PID: 1496 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:173 [kvm]
RIP: 0010:kvm_is_zone_device_pfn+0x96/0xa0 [kvm]
Call Trace:
<TASK>
kvm_set_pfn_dirty+0xa8/0xe0 [kvm]
__handle_changed_spte+0x2ab/0x5e0 [kvm]
__handle_changed_spte+0x2ab/0x5e0 [kvm]
__handle_changed_spte+0x2ab/0x5e0 [kvm]
zap_gfn_range+0x1f3/0x310 [kvm]
kvm_tdp_mmu_zap_invalidated_roots+0x50/0x90 [kvm]
kvm_mmu_zap_all_fast+0x177/0x1a0 [kvm]
set_nx_huge_pages+0xb4/0x190 [kvm]
param_attr_store+0x70/0x100
module_attr_store+0x19/0x30
kernfs_fop_write_iter+0x119/0x1b0
new_sync_write+0x11c/0x1b0
vfs_write+0x1cc/0x270
ksys_write+0x5f/0xe0
do_syscall_64+0x38/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
</TASK>
Fixes: b7cccd397f ("KVM: x86/mmu: Fast invalidation for TDP MMU")
Cc: stable@vger.kernel.org
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211215011557.399940-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 04dc4e6ce2 upstream.
Move the check for an invalid root out of kvm_tdp_mmu_get_root() and into
the one place it actually matters, tdp_mmu_next_root(), as the other user
already has an implicit validity check. A future bug fix will need to
get references to invalid roots to honor mmu_notifier requests; there's
no point in forcing what will be a common path to open code getting a
reference to a root.
No functional change intended.
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211215011557.399940-3-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 83b83a0207 upstream.
Use the common TDP MMU zap helper when handling an MMU notifier unmap
event, the two flows are semantically identical. Consolidate the code in
preparation for a future bug fix, as both kvm_tdp_mmu_unmap_gfn_range()
and __kvm_tdp_mmu_zap_gfn_range() are guilty of not zapping SPTEs in
invalid roots.
No functional change intended.
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211215011557.399940-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Just like on the optional mmu_alloc_direct_roots() path, once shadow
path reaches "r = -EIO" somewhere, the caller needs to know the actual
state in order to enter error handling and avoid something worse.
Fixes: 4a38162ee9 ("KVM: MMU: load PDPTRs outside mmu_lock")
Signed-off-by: Like Xu <likexu@tencent.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220301124941.48412-1-likexu@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In current async pagefault logic, when a page is ready, KVM relies on
kvm_arch_can_dequeue_async_page_present() to determine whether to deliver
a READY event to the Guest. This function test token value of struct
kvm_vcpu_pv_apf_data, which must be reset to zero by Guest kernel when a
READY event is finished by Guest. If value is zero meaning that a READY
event is done, so the KVM can deliver another.
But the kvm_arch_setup_async_pf() may produce a valid token with zero
value, which is confused with previous mention and may lead the loss of
this READY event.
This bug may cause task blocked forever in Guest:
INFO: task stress:7532 blocked for more than 1254 seconds.
Not tainted 5.10.0 #16
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:stress state:D stack: 0 pid: 7532 ppid: 1409
flags:0x00000080
Call Trace:
__schedule+0x1e7/0x650
schedule+0x46/0xb0
kvm_async_pf_task_wait_schedule+0xad/0xe0
? exit_to_user_mode_prepare+0x60/0x70
__kvm_handle_async_pf+0x4f/0xb0
? asm_exc_page_fault+0x8/0x30
exc_page_fault+0x6f/0x110
? asm_exc_page_fault+0x8/0x30
asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x402d00
RSP: 002b:00007ffd31912500 EFLAGS: 00010206
RAX: 0000000000071000 RBX: ffffffffffffffff RCX: 00000000021a32b0
RDX: 000000000007d011 RSI: 000000000007d000 RDI: 00000000021262b0
RBP: 00000000021262b0 R08: 0000000000000003 R09: 0000000000000086
R10: 00000000000000eb R11: 00007fefbdf2baa0 R12: 0000000000000000
R13: 0000000000000002 R14: 000000000007d000 R15: 0000000000001000
Signed-off-by: Liang Zhang <zhangliang5@huawei.com>
Message-Id: <20220222031239.1076682-1-zhangliang5@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- selftest compilation fix for non-x86
- KVM: avoid warning on s390 in mark_page_dirty
x86:
- fix page write-protection bug and improve comments
- use binary search to lookup the PMU event filter, add test
- enable_pmu module parameter support for Intel CPUs
- switch blocked_vcpu_on_cpu_lock to raw spinlock
- cleanups of blocked vCPU logic
- partially allow KVM_SET_CPUID{,2} after KVM_RUN (5.16 regression)
- various small fixes
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more kvm updates from Paolo Bonzini:
"Generic:
- selftest compilation fix for non-x86
- KVM: avoid warning on s390 in mark_page_dirty
x86:
- fix page write-protection bug and improve comments
- use binary search to lookup the PMU event filter, add test
- enable_pmu module parameter support for Intel CPUs
- switch blocked_vcpu_on_cpu_lock to raw spinlock
- cleanups of blocked vCPU logic
- partially allow KVM_SET_CPUID{,2} after KVM_RUN (5.16 regression)
- various small fixes"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (46 commits)
docs: kvm: fix WARNINGs from api.rst
selftests: kvm/x86: Fix the warning in lib/x86_64/processor.c
selftests: kvm/x86: Fix the warning in pmu_event_filter_test.c
kvm: selftests: Do not indent with spaces
kvm: selftests: sync uapi/linux/kvm.h with Linux header
selftests: kvm: add amx_test to .gitignore
KVM: SVM: Nullify vcpu_(un)blocking() hooks if AVIC is disabled
KVM: SVM: Move svm_hardware_setup() and its helpers below svm_x86_ops
KVM: SVM: Drop AVIC's intermediate avic_set_running() helper
KVM: VMX: Don't do full kick when handling posted interrupt wakeup
KVM: VMX: Fold fallback path into triggering posted IRQ helper
KVM: VMX: Pass desired vector instead of bool for triggering posted IRQ
KVM: VMX: Don't do full kick when triggering posted interrupt "fails"
KVM: SVM: Skip AVIC and IRTE updates when loading blocking vCPU
KVM: SVM: Use kvm_vcpu_is_blocking() in AVIC load to handle preemption
KVM: SVM: Remove unnecessary APICv/AVIC update in vCPU unblocking path
KVM: SVM: Don't bother checking for "running" AVIC when kicking for IPIs
KVM: SVM: Signal AVIC doorbell iff vCPU is in guest mode
KVM: x86: Remove defunct pre_block/post_block kvm_x86_ops hooks
KVM: x86: Unexport LAPIC's switch_to_{hv,sw}_timer() helpers
...
Rewrite the comment in kvm_mmu_slot_remove_write_access() that explains
why it is safe to flush TLBs outside of the MMU lock after
write-protecting SPTEs for dirty logging. The current comment is a long
run-on sentence that was difficult to understand. In addition it was
specific to the shadow MMU (mentioning mmu_spte_update()) when the TDP
MMU has to handle this as well.
The new comment explains:
- Why the TLB flush is necessary at all.
- Why it is desirable to do the TLB flush outside of the MMU lock.
- Why it is safe to do the TLB flush outside of the MMU lock.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220113233020.3986005-5-dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SPTEs are tagged with software-only bits to indicate if it is
"MMU-writable" and "Host-writable". These bits are used to determine why
KVM has marked an SPTE as read-only.
Document these bits and their invariants, and enforce the invariants
with new WARNs in spte_can_locklessly_be_made_writable() to ensure they
are not accidentally violated in the future.
Opportunistically move DEFAULT_SPTE_{MMU,HOST}_WRITABLE next to
EPT_SPTE_{MMU,HOST}_WRITABLE since the new documentation applies to
both.
No functional change intended.
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220113233020.3986005-4-dmatlack@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When handling the changed_pte notifier and the new PTE is read-only,
clear both the Host-writable and MMU-writable bits in the SPTE. This
preserves the invariant that MMU-writable is set if-and-only-if
Host-writable is set.
No functional change intended. Nothing currently relies on the
aforementioned invariant and technically the changed_pte notifier is
dead code.
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220113233020.3986005-3-dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When the TDP MMU is write-protection GFNs for page table protection (as
opposed to for dirty logging, or due to the HVA not being writable), it
checks if the SPTE is already write-protected and if so skips modifying
the SPTE and the TLB flush.
This behavior is incorrect because it fails to check if the SPTE
is write-protected for page table protection, i.e. fails to check
that MMU-writable is '0'. If the SPTE was write-protected for dirty
logging but not page table protection, the SPTE could locklessly be made
writable, and vCPUs could still be running with writable mappings cached
in their TLB.
Fix this by only skipping setting the SPTE if the SPTE is already
write-protected *and* MMU-writable is already clear. Technically,
checking only MMU-writable would suffice; a SPTE cannot be writable
without MMU-writable being set. But check both to be paranoid and
because it arguably yields more readable code.
Fixes: 46044f72c3 ("kvm: x86/mmu: Support write protection for nesting in tdp MMU")
Cc: stable@vger.kernel.org
Signed-off-by: David Matlack <dmatlack@google.com>
Message-Id: <20220113233020.3986005-2-dmatlack@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- Use common KVM implementation of MMU memory caches
- SBI v0.2 support for Guest
- Initial KVM selftests support
- Fix to avoid spurious virtual interrupts after clearing hideleg CSR
- Update email address for Anup and Atish
ARM:
- Simplification of the 'vcpu first run' by integrating it into
KVM's 'pid change' flow
- Refactoring of the FP and SVE state tracking, also leading to
a simpler state and less shared data between EL1 and EL2 in
the nVHE case
- Tidy up the header file usage for the nvhe hyp object
- New HYP unsharing mechanism, finally allowing pages to be
unmapped from the Stage-1 EL2 page-tables
- Various pKVM cleanups around refcounting and sharing
- A couple of vgic fixes for bugs that would trigger once
the vcpu xarray rework is merged, but not sooner
- Add minimal support for ARMv8.7's PMU extension
- Rework kvm_pgtable initialisation ahead of the NV work
- New selftest for IRQ injection
- Teach selftests about the lack of default IPA space and
page sizes
- Expand sysreg selftest to deal with Pointer Authentication
- The usual bunch of cleanups and doc update
s390:
- fix sigp sense/start/stop/inconsistency
- cleanups
x86:
- Clean up some function prototypes more
- improved gfn_to_pfn_cache with proper invalidation, used by Xen emulation
- add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery
- completely remove potential TOC/TOU races in nested SVM consistency checks
- update some PMCs on emulated instructions
- Intel AMX support (joint work between Thomas and Intel)
- large MMU cleanups
- module parameter to disable PMU virtualization
- cleanup register cache
- first part of halt handling cleanups
- Hyper-V enlightened MSR bitmap support for nested hypervisors
Generic:
- clean up Makefiles
- introduce CONFIG_HAVE_KVM_DIRTY_RING
- optimize memslot lookup using a tree
- optimize vCPU array usage by converting to xarray
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"RISCV:
- Use common KVM implementation of MMU memory caches
- SBI v0.2 support for Guest
- Initial KVM selftests support
- Fix to avoid spurious virtual interrupts after clearing hideleg CSR
- Update email address for Anup and Atish
ARM:
- Simplification of the 'vcpu first run' by integrating it into KVM's
'pid change' flow
- Refactoring of the FP and SVE state tracking, also leading to a
simpler state and less shared data between EL1 and EL2 in the nVHE
case
- Tidy up the header file usage for the nvhe hyp object
- New HYP unsharing mechanism, finally allowing pages to be unmapped
from the Stage-1 EL2 page-tables
- Various pKVM cleanups around refcounting and sharing
- A couple of vgic fixes for bugs that would trigger once the vcpu
xarray rework is merged, but not sooner
- Add minimal support for ARMv8.7's PMU extension
- Rework kvm_pgtable initialisation ahead of the NV work
- New selftest for IRQ injection
- Teach selftests about the lack of default IPA space and page sizes
- Expand sysreg selftest to deal with Pointer Authentication
- The usual bunch of cleanups and doc update
s390:
- fix sigp sense/start/stop/inconsistency
- cleanups
x86:
- Clean up some function prototypes more
- improved gfn_to_pfn_cache with proper invalidation, used by Xen
emulation
- add KVM_IRQ_ROUTING_XEN_EVTCHN and event channel delivery
- completely remove potential TOC/TOU races in nested SVM consistency
checks
- update some PMCs on emulated instructions
- Intel AMX support (joint work between Thomas and Intel)
- large MMU cleanups
- module parameter to disable PMU virtualization
- cleanup register cache
- first part of halt handling cleanups
- Hyper-V enlightened MSR bitmap support for nested hypervisors
Generic:
- clean up Makefiles
- introduce CONFIG_HAVE_KVM_DIRTY_RING
- optimize memslot lookup using a tree
- optimize vCPU array usage by converting to xarray"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (268 commits)
x86/fpu: Fix inline prefix warnings
selftest: kvm: Add amx selftest
selftest: kvm: Move struct kvm_x86_state to header
selftest: kvm: Reorder vcpu_load_state steps for AMX
kvm: x86: Disable interception for IA32_XFD on demand
x86/fpu: Provide fpu_sync_guest_vmexit_xfd_state()
kvm: selftests: Add support for KVM_CAP_XSAVE2
kvm: x86: Add support for getting/setting expanded xstate buffer
x86/fpu: Add uabi_size to guest_fpu
kvm: x86: Add CPUID support for Intel AMX
kvm: x86: Add XCR0 support for Intel AMX
kvm: x86: Disable RDMSR interception of IA32_XFD_ERR
kvm: x86: Emulate IA32_XFD_ERR for guest
kvm: x86: Intercept #NM for saving IA32_XFD_ERR
x86/fpu: Prepare xfd_err in struct fpu_guest
kvm: x86: Add emulation for IA32_XFD
x86/fpu: Provide fpu_update_guest_xfd() for IA32_XFD emulation
kvm: x86: Enable dynamic xfeatures at KVM_SET_CPUID2
x86/fpu: Provide fpu_enable_guest_xfd_features() for KVM
x86/fpu: Add guest support to xfd_enable_feature()
...
to use it in SEV and TDX guests
- An include fix and reorg to allow for removing set_fs in UML later
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Merge tag 'x86_misc_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc x86 updates from Borislav Petkov:
"The pile which we cannot find the proper topic for so we stick it in
x86/misc:
- Add support for decoding instructions which do MMIO accesses in
order to use it in SEV and TDX guests
- An include fix and reorg to allow for removing set_fs in UML later"
* tag 'x86_misc_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mtrr: Remove the mtrr_bp_init() stub
x86/sev-es: Use insn_decode_mmio() for MMIO implementation
x86/insn-eval: Introduce insn_decode_mmio()
x86/insn-eval: Introduce insn_get_modrm_reg_ptr()
x86/insn-eval: Handle insn_get_opcode() failure
Add an IS_ENABLED() check in setup_arch() and call pat_disable()
directly if MTRRs are not supported. This allows to remove the
<asm/memtype.h> include in <asm/mtrr.h>, which pull in lowlevel x86
headers that should not be included for UML builds and will cause build
warnings with a following patch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211215165612.554426-2-hch@lst.de
Pick commit fdba608f15 ("KVM: VMX: Wake vCPU when delivering posted
IRQ even if vCPU == this vCPU"). In addition to fixing a bug, it
also aligns the non-nested and nested usage of triggering posted
interrupts, allowing for additional cleanups.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
After dropping mmu_lock in the TDP MMU, restart the iterator during
tdp_iter_next() and do not advance the iterator. Advancing the iterator
results in skipping the top-level SPTE and all its children, which is
fatal if any of the skipped SPTEs were not visited before yielding.
When zapping all SPTEs, i.e. when min_level == root_level, restarting the
iter and then invoking tdp_iter_next() is always fatal if the current gfn
has as a valid SPTE, as advancing the iterator results in try_step_side()
skipping the current gfn, which wasn't visited before yielding.
Sprinkle WARNs on iter->yielded being true in various helpers that are
often used in conjunction with yielding, and tag the helper with
__must_check to reduce the probabily of improper usage.
Failing to zap a top-level SPTE manifests in one of two ways. If a valid
SPTE is skipped by both kvm_tdp_mmu_zap_all() and kvm_tdp_mmu_put_root(),
the shadow page will be leaked and KVM will WARN accordingly.
WARNING: CPU: 1 PID: 3509 at arch/x86/kvm/mmu/tdp_mmu.c:46 [kvm]
RIP: 0010:kvm_mmu_uninit_tdp_mmu+0x3e/0x50 [kvm]
Call Trace:
<TASK>
kvm_arch_destroy_vm+0x130/0x1b0 [kvm]
kvm_destroy_vm+0x162/0x2a0 [kvm]
kvm_vcpu_release+0x34/0x60 [kvm]
__fput+0x82/0x240
task_work_run+0x5c/0x90
do_exit+0x364/0xa10
? futex_unqueue+0x38/0x60
do_group_exit+0x33/0xa0
get_signal+0x155/0x850
arch_do_signal_or_restart+0xed/0x750
exit_to_user_mode_prepare+0xc5/0x120
syscall_exit_to_user_mode+0x1d/0x40
do_syscall_64+0x48/0xc0
entry_SYSCALL_64_after_hwframe+0x44/0xae
If kvm_tdp_mmu_zap_all() skips a gfn/SPTE but that SPTE is then zapped by
kvm_tdp_mmu_put_root(), KVM triggers a use-after-free in the form of
marking a struct page as dirty/accessed after it has been put back on the
free list. This directly triggers a WARN due to encountering a page with
page_count() == 0, but it can also lead to data corruption and additional
errors in the kernel.
WARNING: CPU: 7 PID: 1995658 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:171
RIP: 0010:kvm_is_zone_device_pfn.part.0+0x9e/0xd0 [kvm]
Call Trace:
<TASK>
kvm_set_pfn_dirty+0x120/0x1d0 [kvm]
__handle_changed_spte+0x92e/0xca0 [kvm]
__handle_changed_spte+0x63c/0xca0 [kvm]
__handle_changed_spte+0x63c/0xca0 [kvm]
__handle_changed_spte+0x63c/0xca0 [kvm]
zap_gfn_range+0x549/0x620 [kvm]
kvm_tdp_mmu_put_root+0x1b6/0x270 [kvm]
mmu_free_root_page+0x219/0x2c0 [kvm]
kvm_mmu_free_roots+0x1b4/0x4e0 [kvm]
kvm_mmu_unload+0x1c/0xa0 [kvm]
kvm_arch_destroy_vm+0x1f2/0x5c0 [kvm]
kvm_put_kvm+0x3b1/0x8b0 [kvm]
kvm_vcpu_release+0x4e/0x70 [kvm]
__fput+0x1f7/0x8c0
task_work_run+0xf8/0x1a0
do_exit+0x97b/0x2230
do_group_exit+0xda/0x2a0
get_signal+0x3be/0x1e50
arch_do_signal_or_restart+0x244/0x17f0
exit_to_user_mode_prepare+0xcb/0x120
syscall_exit_to_user_mode+0x1d/0x40
do_syscall_64+0x4d/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
Note, the underlying bug existed even before commit 1af4a96025 ("KVM:
x86/mmu: Yield in TDU MMU iter even if no SPTES changed") moved calls to
tdp_mmu_iter_cond_resched() to the beginning of loops, as KVM could still
incorrectly advance past a top-level entry when yielding on a lower-level
entry. But with respect to leaking shadow pages, the bug was introduced
by yielding before processing the current gfn.
Alternatively, tdp_mmu_iter_cond_resched() could simply fall through, or
callers could jump to their "retry" label. The downside of that approach
is that tdp_mmu_iter_cond_resched() _must_ be called before anything else
in the loop, and there's no easy way to enfornce that requirement.
Ideally, KVM would handling the cond_resched() fully within the iterator
macro (the code is actually quite clean) and avoid this entire class of
bugs, but that is extremely difficult do while also supporting yielding
after tdp_mmu_set_spte_atomic() fails. Yielding after failing to set a
SPTE is very desirable as the "owner" of the REMOVED_SPTE isn't strictly
bounded, e.g. if it's zapping a high-level shadow page, the REMOVED_SPTE
may block operations on the SPTE for a significant amount of time.
Fixes: faaf05b00a ("kvm: x86/mmu: Support zapping SPTEs in the TDP MMU")
Fixes: 1af4a96025 ("KVM: x86/mmu: Yield in TDU MMU iter even if no SPTES changed")
Reported-by: Ignat Korchagin <ignat@cloudflare.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211214033528.123268-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Play nice with a NULL shadow page when checking for an obsolete root in
the page fault handler by flagging the page fault as stale if there's no
shadow page associated with the root and KVM_REQ_MMU_RELOAD is pending.
Invalidating memslots, which is the only case where _all_ roots need to
be reloaded, requests all vCPUs to reload their MMUs while holding
mmu_lock for lock.
The "special" roots, e.g. pae_root when KVM uses PAE paging, are not
backed by a shadow page. Running with TDP disabled or with nested NPT
explodes spectaculary due to dereferencing a NULL shadow page pointer.
Skip the KVM_REQ_MMU_RELOAD check if there is a valid shadow page for the
root. Zapping shadow pages in response to guest activity, e.g. when the
guest frees a PGD, can trigger KVM_REQ_MMU_RELOAD even if the current
vCPU isn't using the affected root. I.e. KVM_REQ_MMU_RELOAD can be seen
with a completely valid root shadow page. This is a bit of a moot point
as KVM currently unloads all roots on KVM_REQ_MMU_RELOAD, but that will
be cleaned up in the future.
Fixes: a955cad84c ("KVM: x86/mmu: Retry page fault if root is invalidated by memslot update")
Cc: stable@vger.kernel.org
Cc: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211209060552.2956723-2-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This bit is very close to mean "role.quadrant is not in use", except that
it is false also when the MMU is mapping guest physical addresses
directly. In that case, role.quadrant is indeed not in use, but there
are no guest PTEs at all.
Changing the name and direction of the bit removes the special case,
since a guest with paging disabled, or not considering guest paging
structures as is the case for two-dimensional paging, does not have
to deal with 4-byte guest PTEs.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211124122055.64424-10-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The level of supported large page on nEPT affects the rsvds_bits_mask.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211124122055.64424-8-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Bit 7 on pte depends on the level of supported large page.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211124122055.64424-7-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reduce an indirect function call (retpoline) and some intialization
code.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211124122055.64424-4-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The mmu->gva_to_gpa() has no "struct kvm_mmu *mmu", so an extra
FNAME(gva_to_gpa_nested) is needed.
Add the parameter can simplify the code. And it makes it explicit that
the walk is upon vcpu->arch.walk_mmu for gva and vcpu->arch.mmu for L2
gpa in translate_nested_gpa() via the new parameter.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211124122055.64424-3-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
role.quadrant is only valid when gpte size is 4 bytes and only be
calculated when gpte size is 4 bytes.
Although "vcpu->arch.mmu->root_level <= PT32_ROOT_LEVEL" also means
gpte size is 4 bytes, but using "!role.gpte_is_8_bytes" is clearer
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211118110814.2568-15-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
role.gpte_is_8_bytes is unused when role.direct; there is no
point in changing a bit in the role, the value that was set
when the MMU is initialized is just fine.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211118110814.2568-14-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The allocation of special roots is moved to mmu_alloc_special_roots().
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211118110814.2568-12-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
It is never used.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211118110814.2568-11-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
change 0 to false and 1 to true to fix following cocci warnings:
arch/x86/kvm/mmu/mmu.c:1485:9-10: WARNING: return of 0/1 in function 'kvm_set_pte_rmapp' with return type bool
arch/x86/kvm/mmu/mmu.c:1636:10-11: WARNING: return of 0/1 in function 'kvm_test_age_rmapp' with return type bool
Signed-off-by: Vihas Mak <makvihas@gmail.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Message-Id: <20211114164312.GA28736@makvihas>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In preparation for implementing in-place hugepage promotion, various
functions will need to be called from zap_collapsible_spte_range, which
has the const qualifier on its memslot argument. Propagate the const
qualifier to the various functions which will be needed. This just serves
to simplify the following patch.
No functional change intended.
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211115234603.2908381-11-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The vCPU argument to mmu_try_to_unsync_pages is now only used to get a
pointer to the associated struct kvm, so pass in the kvm pointer from
the beginning to remove the need for a vCPU when calling the function.
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211115234603.2908381-7-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_slot_page_track_is_active only uses its vCPU argument to get a
pointer to the assoicated struct kvm, so just pass in the struct KVM to
remove the need for a vCPU pointer.
No functional change intended.
Signed-off-by: Ben Gardon <bgardon@google.com>
Message-Id: <20211115234603.2908381-6-bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Rework make_spte() to query the shadow page's role, specifically whether
or not it's a guest_mode page, a.k.a. a page for L2, when determining if
the SPTE is compatible with PML. This eliminates a dependency on @vcpu,
with a future goal of being able to create SPTEs without a specific vCPU.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce a memslots gfn upper bound operation and use it to optimize
kvm_zap_gfn_range().
This way this handler can do a quick lookup for intersecting gfns and won't
have to do a linear scan of the whole memslot set.
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <ef242146a87a335ee93b441dcf01665cb847c902.1638817641.git.maciej.szmigiero@oracle.com>
The current memslot code uses a (reverse gfn-ordered) memslot array for
keeping track of them.
Because the memslot array that is currently in use cannot be modified
every memslot management operation (create, delete, move, change flags)
has to make a copy of the whole array so it has a scratch copy to work on.
Strictly speaking, however, it is only necessary to make copy of the
memslot that is being modified, copying all the memslots currently present
is just a limitation of the array-based memslot implementation.
Two memslot sets, however, are still needed so the VM continues to run
on the currently active set while the requested operation is being
performed on the second, currently inactive one.
In order to have two memslot sets, but only one copy of actual memslots
it is necessary to split out the memslot data from the memslot sets.
The memslots themselves should be also kept independent of each other
so they can be individually added or deleted.
These two memslot sets should normally point to the same set of
memslots. They can, however, be desynchronized when performing a
memslot management operation by replacing the memslot to be modified
by its copy. After the operation is complete, both memslot sets once
again point to the same, common set of memslot data.
This commit implements the aforementioned idea.
For tracking of gfns an ordinary rbtree is used since memslots cannot
overlap in the guest address space and so this data structure is
sufficient for ensuring that lookups are done quickly.
The "last used slot" mini-caches (both per-slot set one and per-vCPU one),
that keep track of the last found-by-gfn memslot, are still present in the
new code.
Co-developed-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Message-Id: <17c0cf3663b760a0d3753d4ac08c0753e941b811.1638817641.git.maciej.szmigiero@oracle.com>
There is no point in recalculating from scratch the total number of pages
in all memslots each time a memslot is created or deleted. Use KVM's
cached nr_memslot_pages to compute the default max number of MMU pages.
Note that even with nr_memslot_pages capped at ULONG_MAX we can't safely
multiply it by KVM_PERMILLE_MMU_PAGES (20) since this operation can
possibly overflow an unsigned long variable.
Write this "* 20 / 1000" operation as "/ 50" instead to avoid such
overflow.
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
[sean: use common KVM field and rework changelog accordingly]
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <d14c5a24535269606675437d5602b7dac4ad8c0e.1638817640.git.maciej.szmigiero@oracle.com>
Bail from the page fault handler if the root shadow page was obsoleted by
a memslot update. Do the check _after_ acuiring mmu_lock, as the TDP MMU
doesn't rely on the memslot/MMU generation, and instead relies on the
root being explicit marked invalid by kvm_mmu_zap_all_fast(), which takes
mmu_lock for write.
For the TDP MMU, inserting a SPTE into an obsolete root can leak a SP if
kvm_tdp_mmu_zap_invalidated_roots() has already zapped the SP, i.e. has
moved past the gfn associated with the SP.
For other MMUs, the resulting behavior is far more convoluted, though
unlikely to be truly problematic. Installing SPs/SPTEs into the obsolete
root isn't directly problematic, as the obsolete root will be unloaded
and dropped before the vCPU re-enters the guest. But because the legacy
MMU tracks shadow pages by their role, any SP created by the fault can
can be reused in the new post-reload root. Again, that _shouldn't_ be
problematic as any leaf child SPTEs will be created for the current/valid
memslot generation, and kvm_mmu_get_page() will not reuse child SPs from
the old generation as they will be flagged as obsolete. But, given that
continuing with the fault is pointess (the root will be unloaded), apply
the check to all MMUs.
Fixes: b7cccd397f ("KVM: x86/mmu: Fast invalidation for TDP MMU")
Cc: stable@vger.kernel.org
Cc: Ben Gardon <bgardon@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120045046.3940942-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Account for the '0' being a default, "let KVM choose" period, when
determining whether or not the recovery worker needs to be awakened in
response to userspace reducing the period. Failure to do so results in
the worker not being awakened properly, e.g. when changing the period
from '0' to any small-ish value.
Fixes: 4dfe4f40d8 ("kvm: x86: mmu: Make NX huge page recovery period configurable")
Cc: stable@vger.kernel.org
Cc: Junaid Shahid <junaids@google.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120015706.3830341-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Initialize the mask for PKU permissions as if CR4.PKE=0, avoiding
incorrect interpretations of the nested hypervisor's page tables.
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Drop the "flush" param and return values to/from the TDP MMU's helper for
zapping collapsible SPTEs. Because the helper runs with mmu_lock held
for read, not write, it uses tdp_mmu_zap_spte_atomic(), and the atomic
zap handles the necessary remote TLB flush.
Similarly, because mmu_lock is dropped and re-acquired between zapping
legacy MMUs and zapping TDP MMUs, kvm_mmu_zap_collapsible_sptes() must
handle remote TLB flushes from the legacy MMU before calling into the TDP
MMU.
Fixes: e2209710cc ("KVM: x86/mmu: Skip rmap operations if rmaps not allocated")
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120045046.3940942-4-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use the yield-safe variant of the TDP MMU iterator when handling an
unmapping event from the MMU notifier, as most occurences of the event
allow yielding.
Fixes: e1eed5847b ("KVM: x86/mmu: Allow yielding during MMU notifier unmap/zap, if possible")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211120015008.3780032-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
INVLPG operates on guest virtual address, which are represented by
vcpu->arch.walk_mmu. In nested virtualization scenarios,
kvm_mmu_invlpg() was using the wrong MMU structure; if L2's invlpg were
emulated by L0 (in practice, it hardly happen) when nested two-dimensional
paging is enabled, the call to ->tlb_flush_gva() would be skipped and
the hardware TLB entry would not be invalidated.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211124122055.64424-5-jiangshanlai@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If the is an L1 with nNPT in 32bit, the shadow walk starts with
pae_root.
Fixes: a717a780fc ("KVM: x86/mmu: Support shadowing NPT when 5-level paging is enabled in host)
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Message-Id: <20211124122055.64424-2-jiangshanlai@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 63f5a1909f ("KVM: x86: Alert userspace that KVM_SET_CPUID{,2}
after KVM_RUN is broken") officially deprecated KVM_SET_CPUID{,2} ioctls
after first successful KVM_RUN and promissed to make this sequence forbiden
in 5.16. It's time to fulfil the promise.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211122175818.608220-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since tlb flush has been done for legacy MMU before
kvm_tdp_mmu_zap_collapsible_sptes(), so the parameter flush
should be false for kvm_tdp_mmu_zap_collapsible_sptes().
Fixes: e2209710cc ("KVM: x86/mmu: Skip rmap operations if rmaps not allocated")
Signed-off-by: Hou Wenlong <houwenlong93@linux.alibaba.com>
Message-Id: <21453a1d2533afb6e59fb6c729af89e771ff2e76.1637140154.git.houwenlong93@linux.alibaba.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
