Pull struct file leak fixes from Al Viro:
"a couple of leaks on failure exits missing fdput()"
* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
lirc: rc_dev_get_from_fd(): fix file leak
powerpc: fix a file leak in kvm_vcpu_ioctl_enable_cap()
Pull kvm updates from Paolo Bonzini:
"ARM:
- Initial infrastructure for shadow stage-2 MMUs, as part of nested
virtualization enablement
- Support for userspace changes to the guest CTR_EL0 value, enabling
(in part) migration of VMs between heterogenous hardware
- Fixes + improvements to pKVM's FF-A proxy, adding support for v1.1
of the protocol
- FPSIMD/SVE support for nested, including merged trap configuration
and exception routing
- New command-line parameter to control the WFx trap behavior under
KVM
- Introduce kCFI hardening in the EL2 hypervisor
- Fixes + cleanups for handling presence/absence of FEAT_TCRX
- Miscellaneous fixes + documentation updates
LoongArch:
- Add paravirt steal time support
- Add support for KVM_DIRTY_LOG_INITIALLY_SET
- Add perf kvm-stat support for loongarch
RISC-V:
- Redirect AMO load/store access fault traps to guest
- perf kvm stat support
- Use guest files for IMSIC virtualization, when available
s390:
- Assortment of tiny fixes which are not time critical
x86:
- Fixes for Xen emulation
- Add a global struct to consolidate tracking of host values, e.g.
EFER
- Add KVM_CAP_X86_APIC_BUS_CYCLES_NS to allow configuring the
effective APIC bus frequency, because TDX
- Print the name of the APICv/AVIC inhibits in the relevant
tracepoint
- Clean up KVM's handling of vendor specific emulation to
consistently act on "compatible with Intel/AMD", versus checking
for a specific vendor
- Drop MTRR virtualization, and instead always honor guest PAT on
CPUs that support self-snoop
- Update to the newfangled Intel CPU FMS infrastructure
- Don't advertise IA32_PERF_GLOBAL_OVF_CTRL as an MSR-to-be-saved, as
it reads '0' and writes from userspace are ignored
- Misc cleanups
x86 - MMU:
- Small cleanups, renames and refactoring extracted from the upcoming
Intel TDX support
- Don't allocate kvm_mmu_page.shadowed_translation for shadow pages
that can't hold leafs SPTEs
- Unconditionally drop mmu_lock when allocating TDP MMU page tables
for eager page splitting, to avoid stalling vCPUs when splitting
huge pages
- Bug the VM instead of simply warning if KVM tries to split a SPTE
that is non-present or not-huge. KVM is guaranteed to end up in a
broken state because the callers fully expect a valid SPTE, it's
all but dangerous to let more MMU changes happen afterwards
x86 - AMD:
- Make per-CPU save_area allocations NUMA-aware
- Force sev_es_host_save_area() to be inlined to avoid calling into
an instrumentable function from noinstr code
- Base support for running SEV-SNP guests. API-wise, this includes a
new KVM_X86_SNP_VM type, encrypting/measure the initial image into
guest memory, and finalizing it before launching it. Internally,
there are some gmem/mmu hooks needed to prepare gmem-allocated
pages before mapping them into guest private memory ranges
This includes basic support for attestation guest requests, enough
to say that KVM supports the GHCB 2.0 specification
There is no support yet for loading into the firmware those signing
keys to be used for attestation requests, and therefore no need yet
for the host to provide certificate data for those keys.
To support fetching certificate data from userspace, a new KVM exit
type will be needed to handle fetching the certificate from
userspace.
An attempt to define a new KVM_EXIT_COCO / KVM_EXIT_COCO_REQ_CERTS
exit type to handle this was introduced in v1 of this patchset, but
is still being discussed by community, so for now this patchset
only implements a stub version of SNP Extended Guest Requests that
does not provide certificate data
x86 - Intel:
- Remove an unnecessary EPT TLB flush when enabling hardware
- Fix a series of bugs that cause KVM to fail to detect nested
pending posted interrupts as valid wake eents for a vCPU executing
HLT in L2 (with HLT-exiting disable by L1)
- KVM: x86: Suppress MMIO that is triggered during task switch
emulation
Explicitly suppress userspace emulated MMIO exits that are
triggered when emulating a task switch as KVM doesn't support
userspace MMIO during complex (multi-step) emulation
Silently ignoring the exit request can result in the
WARN_ON_ONCE(vcpu->mmio_needed) firing if KVM exits to userspace
for some other reason prior to purging mmio_needed
See commit 0dc902267c ("KVM: x86: Suppress pending MMIO write
exits if emulator detects exception") for more details on KVM's
limitations with respect to emulated MMIO during complex emulator
flows
Generic:
- Rename the AS_UNMOVABLE flag that was introduced for KVM to
AS_INACCESSIBLE, because the special casing needed by these pages
is not due to just unmovability (and in fact they are only
unmovable because the CPU cannot access them)
- New ioctl to populate the KVM page tables in advance, which is
useful to mitigate KVM page faults during guest boot or after live
migration. The code will also be used by TDX, but (probably) not
through the ioctl
- Enable halt poll shrinking by default, as Intel found it to be a
clear win
- Setup empty IRQ routing when creating a VM to avoid having to
synchronize SRCU when creating a split IRQCHIP on x86
- Rework the sched_in/out() paths to replace kvm_arch_sched_in() with
a flag that arch code can use for hooking both sched_in() and
sched_out()
- Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
truncating a bogus value from userspace, e.g. to help userspace
detect bugs
- Mark a vCPU as preempted if and only if it's scheduled out while in
the KVM_RUN loop, e.g. to avoid marking it preempted and thus
writing guest memory when retrieving guest state during live
migration blackout
Selftests:
- Remove dead code in the memslot modification stress test
- Treat "branch instructions retired" as supported on all AMD Family
17h+ CPUs
- Print the guest pseudo-RNG seed only when it changes, to avoid
spamming the log for tests that create lots of VMs
- Make the PMU counters test less flaky when counting LLC cache
misses by doing CLFLUSH{OPT} in every loop iteration"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
crypto: ccp: Add the SNP_VLEK_LOAD command
KVM: x86/pmu: Add kvm_pmu_call() to simplify static calls of kvm_pmu_ops
KVM: x86: Introduce kvm_x86_call() to simplify static calls of kvm_x86_ops
KVM: x86: Replace static_call_cond() with static_call()
KVM: SEV: Provide support for SNP_EXTENDED_GUEST_REQUEST NAE event
x86/sev: Move sev_guest.h into common SEV header
KVM: SEV: Provide support for SNP_GUEST_REQUEST NAE event
KVM: x86: Suppress MMIO that is triggered during task switch emulation
KVM: x86/mmu: Clean up make_huge_page_split_spte() definition and intro
KVM: x86/mmu: Bug the VM if KVM tries to split a !hugepage SPTE
KVM: selftests: x86: Add test for KVM_PRE_FAULT_MEMORY
KVM: x86: Implement kvm_arch_vcpu_pre_fault_memory()
KVM: x86/mmu: Make kvm_mmu_do_page_fault() return mapped level
KVM: x86/mmu: Account pf_{fixed,emulate,spurious} in callers of "do page fault"
KVM: x86/mmu: Bump pf_taken stat only in the "real" page fault handler
KVM: Add KVM_PRE_FAULT_MEMORY vcpu ioctl to pre-populate guest memory
KVM: Document KVM_PRE_FAULT_MEMORY ioctl
mm, virt: merge AS_UNMOVABLE and AS_INACCESSIBLE
perf kvm: Add kvm-stat for loongarch64
LoongArch: KVM: Add PV steal time support in guest side
...
Pull powerpc updates from Michael Ellerman:
- Remove support for 40x CPUs & platforms
- Add support to the 64-bit BPF JIT for cpu v4 instructions
- Fix PCI hotplug driver crash on powernv
- Fix doorbell emulation for KVM on PAPR guests (nestedv2)
- Fix KVM nested guest handling of some less used SPRs
- Online NUMA nodes with no CPU/memory if they have a PCI device
attached
- Reduce memory overhead of enabling kfence on 64-bit Radix MMU kernels
- Reimplement the iommu table_group_ops for pseries for VFIO SPAPR TCE
Thanks to: Anjali K, Artem Savkov, Athira Rajeev, Breno Leitao, Brian
King, Celeste Liu, Christophe Leroy, Esben Haabendal, Gaurav Batra,
Gautam Menghani, Haren Myneni, Hari Bathini, Jeff Johnson, Krishna
Kumar, Krzysztof Kozlowski, Nathan Lynch, Nicholas Piggin, Nick Bowler,
Nilay Shroff, Rob Herring (Arm), Shawn Anastasio, Shivaprasad G Bhat,
Sourabh Jain, Srikar Dronamraju, Timothy Pearson, Uwe Kleine-König, and
Vaibhav Jain.
* tag 'powerpc-6.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (57 commits)
Documentation/powerpc: Mention 40x is removed
powerpc: Remove 40x leftovers
macintosh/therm_windtunnel: fix module unload.
powerpc: Check only single values are passed to CPU/MMU feature checks
powerpc/xmon: Fix disassembly CPU feature checks
powerpc: Drop clang workaround for builtin constant checks
powerpc64/bpf: jit support for signed division and modulo
powerpc64/bpf: jit support for sign extended mov
powerpc64/bpf: jit support for sign extended load
powerpc64/bpf: jit support for unconditional byte swap
powerpc64/bpf: jit support for 32bit offset jmp instruction
powerpc/pci: Hotplug driver bridge support
pci/hotplug/pnv_php: Fix hotplug driver crash on Powernv
powerpc/configs: Update defconfig with now user-visible CONFIG_FSL_IFC
powerpc: add missing MODULE_DESCRIPTION() macros
macintosh/mac_hid: add MODULE_DESCRIPTION()
KVM: PPC: add missing MODULE_DESCRIPTION() macros
powerpc/kexec: Use of_property_read_reg()
powerpc/64s/radix/kfence: map __kfence_pool at page granularity
powerpc/pseries/iommu: Define spapr_tce_table_group_ops only with CONFIG_IOMMU_API
...
KVM generic changes for 6.11
- Enable halt poll shrinking by default, as Intel found it to be a clear win.
- Setup empty IRQ routing when creating a VM to avoid having to synchronize
SRCU when creating a split IRQCHIP on x86.
- Rework the sched_in/out() paths to replace kvm_arch_sched_in() with a flag
that arch code can use for hooking both sched_in() and sched_out().
- Take the vCPU @id as an "unsigned long" instead of "u32" to avoid
truncating a bogus value from userspace, e.g. to help userspace detect bugs.
- Mark a vCPU as preempted if and only if it's scheduled out while in the
KVM_RUN loop, e.g. to avoid marking it preempted and thus writing guest
memory when retrieving guest state during live migration blackout.
- A few minor cleanups
With ARCH=powerpc, make allmodconfig && make W=1 C=1 reports:
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/kvm/test-guest-state-buffer.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/kvm/kvm-pr.o
WARNING: modpost: missing MODULE_DESCRIPTION() in arch/powerpc/kvm/kvm-hv.o
Add the missing invocations of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
[mpe: Change kvm-hv description to mention POWER8 & later]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240615-md-powerpc-arch-powerpc-kvm-v1-1-7478648b3100@quicinc.com
Introduce vcpu->wants_to_run to indicate when a vCPU is in its core run
loop, i.e. when the vCPU is running the KVM_RUN ioctl and immediate_exit
was not set.
Replace all references to vcpu->run->immediate_exit with
!vcpu->wants_to_run to avoid TOCTOU races with userspace. For example, a
malicious userspace could invoked KVM_RUN with immediate_exit=true and
then after KVM reads it to set wants_to_run=false, flip it to false.
This would result in the vCPU running in KVM_RUN with
wants_to_run=false. This wouldn't cause any real bugs today but is a
dangerous landmine.
Signed-off-by: David Matlack <dmatlack@google.com>
Link: https://lore.kernel.org/r/20240503181734.1467938-2-dmatlack@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Al reported a possible use-after-free (UAF) in kvm_spapr_tce_attach_iommu_group().
It looks up `stt` from tablefd, but then continues to use it after doing
fdput() on the returned fd. After the fdput() the tablefd is free to be
closed by another thread. The close calls kvm_spapr_tce_release() and
then release_spapr_tce_table() (via call_rcu()) which frees `stt`.
Although there are calls to rcu_read_lock() in
kvm_spapr_tce_attach_iommu_group() they are not sufficient to prevent
the UAF, because `stt` is used outside the locked regions.
With an artifcial delay after the fdput() and a userspace program which
triggers the race, KASAN detects the UAF:
BUG: KASAN: slab-use-after-free in kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]
Read of size 4 at addr c000200027552c30 by task kvm-vfio/2505
CPU: 54 PID: 2505 Comm: kvm-vfio Not tainted 6.10.0-rc3-next-20240612-dirty #1
Hardware name: 8335-GTH POWER9 0x4e1202 opal:skiboot-v6.5.3-35-g1851b2a06 PowerNV
Call Trace:
dump_stack_lvl+0xb4/0x108 (unreliable)
print_report+0x2b4/0x6ec
kasan_report+0x118/0x2b0
__asan_load4+0xb8/0xd0
kvm_spapr_tce_attach_iommu_group+0x298/0x720 [kvm]
kvm_vfio_set_attr+0x524/0xac0 [kvm]
kvm_device_ioctl+0x144/0x240 [kvm]
sys_ioctl+0x62c/0x1810
system_call_exception+0x190/0x440
system_call_vectored_common+0x15c/0x2ec
...
Freed by task 0:
...
kfree+0xec/0x3e0
release_spapr_tce_table+0xd4/0x11c [kvm]
rcu_core+0x568/0x16a0
handle_softirqs+0x23c/0x920
do_softirq_own_stack+0x6c/0x90
do_softirq_own_stack+0x58/0x90
__irq_exit_rcu+0x218/0x2d0
irq_exit+0x30/0x80
arch_local_irq_restore+0x128/0x230
arch_local_irq_enable+0x1c/0x30
cpuidle_enter_state+0x134/0x5cc
cpuidle_enter+0x6c/0xb0
call_cpuidle+0x7c/0x100
do_idle+0x394/0x410
cpu_startup_entry+0x60/0x70
start_secondary+0x3fc/0x410
start_secondary_prolog+0x10/0x14
Fix it by delaying the fdput() until `stt` is no longer in use, which
is effectively the entire function. To keep the patch minimal add a call
to fdput() at each of the existing return paths. Future work can convert
the function to goto or __cleanup style cleanup.
With the fix in place the test case no longer triggers the UAF.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Closes: https://lore.kernel.org/all/20240610024437.GA1464458@ZenIV/
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240614122910.3499489-1-mpe@ellerman.id.au
Doorbell emulation is broken for KVM on PAPR guests as support for DPDES
was not added in the initial patch series. Due to this, a KVM on PAPR
guest with SMT > 1 cannot be booted with the XICS interrupt controller
as doorbells are setup in the initial probe path when using XICS
(pSeries_smp_probe()).
Command to replicate the above bug:
qemu-system-ppc64 \
-drive file=rhel.qcow2,format=qcow2 \
-m 20G \
-smp 8,cores=1,threads=8 \
-cpu host \
-nographic \
-machine pseries,ic-mode=xics -accel kvm
Add doorbell state handling support in the host KVM code to fix doorbell
emulation.
Fixes: 19d31c5f11 ("KVM: PPC: Add support for nestedv2 guests")
Cc: stable@vger.kernel.org # v6.7+
Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240605113913.83715-3-gautam@linux.ibm.com
PAPR hypervisor has introduced three new counters in the VPA area of
LPAR CPUs for KVM L2 guest (see [1] for terminology) observability - two
for context switches from host to guest and vice versa, and one counter
for getting the total time spent inside the KVM guest. Add a tracepoint
that enables reading the counters for use by ftrace/perf. Note that this
tracepoint is only available for nestedv2 API (i.e, KVM on PowerVM).
[1] Terminology:
a. L1 refers to the VM (LPAR) booted on top of PAPR hypervisor
b. L2 refers to the KVM guest booted on top of L1.
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Naveen N Rao <naveen@kernel.org>
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Gautam Menghani <gautam@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240520175742.196329-1-gautam@linux.ibm.com
Pull powerpc updates from Michael Ellerman:
- Enable BPF Kernel Functions (kfuncs) in the powerpc BPF JIT.
- Allow per-process DEXCR (Dynamic Execution Control Register) settings
via prctl, notably NPHIE which controls hashst/hashchk for ROP
protection.
- Install powerpc selftests in sub-directories. Note this changes the
way run_kselftest.sh needs to be invoked for powerpc selftests.
- Change fadump (Firmware Assisted Dump) to better handle memory
add/remove.
- Add support for passing additional parameters to the fadump kernel.
- Add support for updating the kdump image on CPU/memory add/remove
events.
- Other small features, cleanups and fixes.
Thanks to Andrew Donnellan, Andy Shevchenko, Aneesh Kumar K.V, Arnd
Bergmann, Benjamin Gray, Bjorn Helgaas, Christian Zigotzky, Christophe
Jaillet, Christophe Leroy, Colin Ian King, Cédric Le Goater, Dr. David
Alan Gilbert, Erhard Furtner, Frank Li, GUO Zihua, Ganesh Goudar, Geoff
Levand, Ghanshyam Agrawal, Greg Kurz, Hari Bathini, Joel Stanley, Justin
Stitt, Kunwu Chan, Li Yang, Lidong Zhong, Madhavan Srinivasan, Mahesh
Salgaonkar, Masahiro Yamada, Matthias Schiffer, Naresh Kamboju, Nathan
Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Miehlbradt, Ran Wang,
Randy Dunlap, Ritesh Harjani, Sachin Sant, Shirisha Ganta, Shrikanth
Hegde, Sourabh Jain, Stephen Rothwell, sundar, Thorsten Blum, Vaibhav
Jain, Xiaowei Bao, Yang Li, and Zhao Chenhui.
* tag 'powerpc-6.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (85 commits)
powerpc/fadump: Fix section mismatch warning
powerpc/85xx: fix compile error without CONFIG_CRASH_DUMP
powerpc/fadump: update documentation about bootargs_append
powerpc/fadump: pass additional parameters when fadump is active
powerpc/fadump: setup additional parameters for dump capture kernel
powerpc/pseries/fadump: add support for multiple boot memory regions
selftests/powerpc/dexcr: Fix spelling mistake "predicition" -> "prediction"
KVM: PPC: Book3S HV nestedv2: Fix an error handling path in gs_msg_ops_kvmhv_nestedv2_config_fill_info()
KVM: PPC: Fix documentation for ppc mmu caps
KVM: PPC: code cleanup for kvmppc_book3s_irqprio_deliver
KVM: PPC: Book3S HV nestedv2: Cancel pending DEC exception
powerpc/xmon: Check cpu id in commands "c#", "dp#" and "dx#"
powerpc/code-patching: Use dedicated memory routines for patching
powerpc/code-patching: Test patch_instructions() during boot
powerpc64/kasan: Pass virtual addresses to kasan_init_phys_region()
powerpc: rename SPRN_HID2 define to SPRN_HID2_750FX
powerpc: Fix typos
powerpc/eeh: Fix spelling of the word "auxillary" and update comment
macintosh/ams: Fix unused variable warning
powerpc/Makefile: Remove bits related to the previous use of -mcmodel=large
...
Pull KVM updates from Paolo Bonzini:
"ARM:
- Move a lot of state that was previously stored on a per vcpu basis
into a per-CPU area, because it is only pertinent to the host while
the vcpu is loaded. This results in better state tracking, and a
smaller vcpu structure.
- Add full handling of the ERET/ERETAA/ERETAB instructions in nested
virtualisation. The last two instructions also require emulating
part of the pointer authentication extension. As a result, the trap
handling of pointer authentication has been greatly simplified.
- Turn the global (and not very scalable) LPI translation cache into
a per-ITS, scalable cache, making non directly injected LPIs much
cheaper to make visible to the vcpu.
- A batch of pKVM patches, mostly fixes and cleanups, as the
upstreaming process seems to be resuming. Fingers crossed!
- Allocate PPIs and SGIs outside of the vcpu structure, allowing for
smaller EL2 mapping and some flexibility in implementing more or
less than 32 private IRQs.
- Purge stale mpidr_data if a vcpu is created after the MPIDR map has
been created.
- Preserve vcpu-specific ID registers across a vcpu reset.
- Various minor cleanups and improvements.
LoongArch:
- Add ParaVirt IPI support
- Add software breakpoint support
- Add mmio trace events support
RISC-V:
- Support guest breakpoints using ebreak
- Introduce per-VCPU mp_state_lock and reset_cntx_lock
- Virtualize SBI PMU snapshot and counter overflow interrupts
- New selftests for SBI PMU and Guest ebreak
- Some preparatory work for both TDX and SNP page fault handling.
This also cleans up the page fault path, so that the priorities of
various kinds of fauls (private page, no memory, write to read-only
slot, etc.) are easier to follow.
x86:
- Minimize amount of time that shadow PTEs remain in the special
REMOVED_SPTE state.
This is a state where the mmu_lock is held for reading but
concurrent accesses to the PTE have to spin; shortening its use
allows other vCPUs to repopulate the zapped region while the zapper
finishes tearing down the old, defunct page tables.
- Advertise the max mappable GPA in the "guest MAXPHYADDR" CPUID
field, which is defined by hardware but left for software use.
This lets KVM communicate its inability to map GPAs that set bits
51:48 on hosts without 5-level nested page tables. Guest firmware
is expected to use the information when mapping BARs; this avoids
that they end up at a legal, but unmappable, GPA.
- Fixed a bug where KVM would not reject accesses to MSR that aren't
supposed to exist given the vCPU model and/or KVM configuration.
- As usual, a bunch of code cleanups.
x86 (AMD):
- Implement a new and improved API to initialize SEV and SEV-ES VMs,
which will also be extendable to SEV-SNP.
The new API specifies the desired encryption in KVM_CREATE_VM and
then separately initializes the VM. The new API also allows
customizing the desired set of VMSA features; the features affect
the measurement of the VM's initial state, and therefore enabling
them cannot be done tout court by the hypervisor.
While at it, the new API includes two bugfixes that couldn't be
applied to the old one without a flag day in userspace or without
affecting the initial measurement. When a SEV-ES VM is created with
the new VM type, KVM_GET_REGS/KVM_SET_REGS and friends are rejected
once the VMSA has been encrypted. Also, the FPU and AVX state will
be synchronized and encrypted too.
- Support for GHCB version 2 as applicable to SEV-ES guests.
This, once more, is only accessible when using the new
KVM_SEV_INIT2 flow for initialization of SEV-ES VMs.
x86 (Intel):
- An initial bunch of prerequisite patches for Intel TDX were merged.
They generally don't do anything interesting. The only somewhat
user visible change is a new debugging mode that checks that KVM's
MMU never triggers a #VE virtualization exception in the guest.
- Clear vmcs.EXIT_QUALIFICATION when synthesizing an EPT Misconfig
VM-Exit to L1, as per the SDM.
Generic:
- Use vfree() instead of kvfree() for allocations that always use
vcalloc() or __vcalloc().
- Remove .change_pte() MMU notifier - the changes to non-KVM code are
small and Andrew Morton asked that I also take those through the
KVM tree.
The callback was only ever implemented by KVM (which was also the
original user of MMU notifiers) but it had been nonfunctional ever
since calls to set_pte_at_notify were wrapped with
invalidate_range_start and invalidate_range_end... in 2012.
Selftests:
- Enhance the demand paging test to allow for better reporting and
stressing of UFFD performance.
- Convert the steal time test to generate TAP-friendly output.
- Fix a flaky false positive in the xen_shinfo_test due to comparing
elapsed time across two different clock domains.
- Skip the MONITOR/MWAIT test if the host doesn't actually support
MWAIT.
- Avoid unnecessary use of "sudo" in the NX hugepage test wrapper
shell script, to play nice with running in a minimal userspace
environment.
- Allow skipping the RSEQ test's sanity check that the vCPU was able
to complete a reasonable number of KVM_RUNs, as the assert can fail
on a completely valid setup.
If the test is run on a large-ish system that is otherwise idle,
and the test isn't affined to a low-ish number of CPUs, the vCPU
task can be repeatedly migrated to CPUs that are in deep sleep
states, which results in the vCPU having very little net runtime
before the next migration due to high wakeup latencies.
- Define _GNU_SOURCE for all selftests to fix a warning that was
introduced by a change to kselftest_harness.h late in the 6.9
cycle, and because forcing every test to #define _GNU_SOURCE is
painful.
- Provide a global pseudo-RNG instance for all tests, so that library
code can generate random, but determinstic numbers.
- Use the global pRNG to randomly force emulation of select writes
from guest code on x86, e.g. to help validate KVM's emulation of
locked accesses.
- Allocate and initialize x86's GDT, IDT, TSS, segments, and default
exception handlers at VM creation, instead of forcing tests to
manually trigger the related setup.
Documentation:
- Fix a goof in the KVM_CREATE_GUEST_MEMFD documentation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (225 commits)
selftests/kvm: remove dead file
KVM: selftests: arm64: Test vCPU-scoped feature ID registers
KVM: selftests: arm64: Test that feature ID regs survive a reset
KVM: selftests: arm64: Store expected register value in set_id_regs
KVM: selftests: arm64: Rename helper in set_id_regs to imply VM scope
KVM: arm64: Only reset vCPU-scoped feature ID regs once
KVM: arm64: Reset VM feature ID regs from kvm_reset_sys_regs()
KVM: arm64: Rename is_id_reg() to imply VM scope
KVM: arm64: Destroy mpidr_data for 'late' vCPU creation
KVM: arm64: Use hVHE in pKVM by default on CPUs with VHE support
KVM: arm64: Fix hvhe/nvhe early alias parsing
KVM: SEV: Allow per-guest configuration of GHCB protocol version
KVM: SEV: Add GHCB handling for termination requests
KVM: SEV: Add GHCB handling for Hypervisor Feature Support requests
KVM: SEV: Add support to handle AP reset MSR protocol
KVM: x86: Explicitly zero kvm_caps during vendor module load
KVM: x86: Fully re-initialize supported_mce_cap on vendor module load
KVM: x86: Fully re-initialize supported_vm_types on vendor module load
KVM: x86/mmu: Sanity check that __kvm_faultin_pfn() doesn't create noslot pfns
KVM: x86/mmu: Initialize kvm_page_fault's pfn and hva to error values
...
This reverts commit 180c6b072b ("KVM: PPC: Book3S HV nestedv2: Do not
cancel pending decrementer exception") [1] which prevented canceling a
pending HDEC exception for nestedv2 KVM guests. It was done to avoid
overhead of a H_GUEST_GET_STATE hcall to read the 'DEC expiry TB' register
which was higher compared to handling extra decrementer exceptions.
However recent benchmarks indicate that overhead of not handling 'DECR'
expiry for Nested KVM Guest(L2) is higher and results in much larger exits
to Pseries Host(L1) as indicated by the Unixbench-arithoh bench[2]
Metric | Current upstream | Revert [1] | Difference %
========================================================================
arithoh-count (10) | 3244831634 | 3403089673 | +04.88%
kvm_hv:kvm_guest_exit | 513558 | 152441 | -70.32%
probe:kvmppc_gsb_recv | 28060 | 28110 | +00.18%
N=1
As indicated by the data above that reverting [1] results in substantial
reduction in number of L2->L1 exits with only slight increase in number of
H_GUEST_GET_STATE hcalls to read the value of 'DEC expiry TB'. This results
in an overall ~4% improvement of arithoh[2] throughput.
[1] commit 180c6b072b ("KVM: PPC: Book3S HV nestedv2: Do not cancel pending decrementer exception")
[2] https://github.com/kdlucas/byte-unixbench/
Fixes: 180c6b072b ("KVM: PPC: Book3S HV nestedv2: Do not cancel pending decrementer exception")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240415035731.103097-1-vaibhav@linux.ibm.com
The irq_desc::kstat_irqs member is a per-CPU variable of type int, which is
only capable of counting. A snapshot mechanism for interrupt statistics
will be added soon, which requires an additional variable to store the
snapshot.
To facilitate expansion, convert kstat_irqs here to a struct containing
only the count.
Originally-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Bitao Hu <yaoma@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240411074134.30922-2-yaoma@linux.alibaba.com
The .change_pte() MMU notifier callback was intended as an
optimization. The original point of it was that KSM could tell KVM to flip
its secondary PTE to a new location without having to first zap it. At
the time there was also an .invalidate_page() callback; both of them were
*not* bracketed by calls to mmu_notifier_invalidate_range_{start,end}(),
and .invalidate_page() also doubled as a fallback implementation of
.change_pte().
Later on, however, both callbacks were changed to occur within an
invalidate_range_start/end() block.
In the case of .change_pte(), commit 6bdb913f0a ("mm: wrap calls to
set_pte_at_notify with invalidate_range_start and invalidate_range_end",
2012-10-09) did so to remove the fallback from .invalidate_page() to
.change_pte() and allow sleepable .invalidate_page() hooks.
This however made KVM's usage of the .change_pte() callback completely
moot, because KVM unmaps the sPTEs during .invalidate_range_start()
and therefore .change_pte() has no hope of finding a sPTE to change.
Drop the generic KVM code that dispatches to kvm_set_spte_gfn(), as
well as all the architecture specific implementations.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Anup Patel <anup@brainfault.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Bibo Mao <maobibo@loongson.cn>
Message-ID: <20240405115815.3226315-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull powerpc updates from Michael Ellerman:
- Add AT_HWCAP3 and AT_HWCAP4 aux vector entries for future use
by glibc
- Add support for recognising the Power11 architected and raw PVRs
- Add support for nr_cpus=n on the command line where the
boot CPU is >= n
- Add ppcxx_allmodconfig targets for all 32-bit sub-arches
- Other small features, cleanups and fixes
Thanks to Akanksha J N, Brian King, Christophe Leroy, Dawei Li, Geoff
Levand, Greg Kroah-Hartman, Jan-Benedict Glaw, Kajol Jain, Kunwu Chan,
Li zeming, Madhavan Srinivasan, Masahiro Yamada, Nathan Chancellor,
Nicholas Piggin, Peter Bergner, Qiheng Lin, Randy Dunlap, Ricardo B.
Marliere, Rob Herring, Sathvika Vasireddy, Shrikanth Hegde, Uwe
Kleine-König, Vaibhav Jain, and Wen Xiong.
* tag 'powerpc-6.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (71 commits)
powerpc/macio: Make remove callback of macio driver void returned
powerpc/83xx: Fix build failure with FPU=n
powerpc/64s: Fix get_hugepd_cache_index() build failure
powerpc/4xx: Fix warp_gpio_leds build failure
powerpc/amigaone: Make several functions static
powerpc/embedded6xx: Fix no previous prototype for avr_uart_send() etc.
macintosh/adb: make adb_dev_class constant
powerpc: xor_vmx: Add '-mhard-float' to CFLAGS
powerpc/fsl: Fix mfpmr() asm constraint error
powerpc: Remove cpu-as-y completely
powerpc/fsl: Modernise mt/mfpmr
powerpc/fsl: Fix mfpmr build errors with newer binutils
powerpc/64s: Use .machine power4 around dcbt
powerpc/64s: Move dcbt/dcbtst sequence into a macro
powerpc/mm: Code cleanup for __hash_page_thp
powerpc/hv-gpci: Fix the H_GET_PERF_COUNTER_INFO hcall return value checks
powerpc/irq: Allow softirq to hardirq stack transition
powerpc: Stop using of_root
powerpc/machdep: Define 'compatibles' property in ppc_md and use it
of: Reimplement of_machine_is_compatible() using of_machine_compatible_match()
...
Pull kvm updates from Paolo Bonzini:
"S390:
- Changes to FPU handling came in via the main s390 pull request
- Only deliver to the guest the SCLP events that userspace has
requested
- More virtual vs physical address fixes (only a cleanup since
virtual and physical address spaces are currently the same)
- Fix selftests undefined behavior
x86:
- Fix a restriction that the guest can't program a PMU event whose
encoding matches an architectural event that isn't included in the
guest CPUID. The enumeration of an architectural event only says
that if a CPU supports an architectural event, then the event can
be programmed *using the architectural encoding*. The enumeration
does NOT say anything about the encoding when the CPU doesn't
report support the event *in general*. It might support it, and it
might support it using the same encoding that made it into the
architectural PMU spec
- Fix a variety of bugs in KVM's emulation of RDPMC (more details on
individual commits) and add a selftest to verify KVM correctly
emulates RDMPC, counter availability, and a variety of other
PMC-related behaviors that depend on guest CPUID and therefore are
easier to validate with selftests than with custom guests (aka
kvm-unit-tests)
- Zero out PMU state on AMD if the virtual PMU is disabled, it does
not cause any bug but it wastes time in various cases where KVM
would check if a PMC event needs to be synthesized
- Optimize triggering of emulated events, with a nice ~10%
performance improvement in VM-Exit microbenchmarks when a vPMU is
exposed to the guest
- Tighten the check for "PMI in guest" to reduce false positives if
an NMI arrives in the host while KVM is handling an IRQ VM-Exit
- Fix a bug where KVM would report stale/bogus exit qualification
information when exiting to userspace with an internal error exit
code
- Add a VMX flag in /proc/cpuinfo to report 5-level EPT support
- Rework TDP MMU root unload, free, and alloc to run with mmu_lock
held for read, e.g. to avoid serializing vCPUs when userspace
deletes a memslot
- Tear down TDP MMU page tables at 4KiB granularity (used to be
1GiB). KVM doesn't support yielding in the middle of processing a
zap, and 1GiB granularity resulted in multi-millisecond lags that
are quite impolite for CONFIG_PREEMPT kernels
- Allocate write-tracking metadata on-demand to avoid the memory
overhead when a kernel is built with i915 virtualization support
but the workloads use neither shadow paging nor i915 virtualization
- Explicitly initialize a variety of on-stack variables in the
emulator that triggered KMSAN false positives
- Fix the debugregs ABI for 32-bit KVM
- Rework the "force immediate exit" code so that vendor code
ultimately decides how and when to force the exit, which allowed
some optimization for both Intel and AMD
- Fix a long-standing bug where kvm_has_noapic_vcpu could be left
elevated if vCPU creation ultimately failed, causing extra
unnecessary work
- Cleanup the logic for checking if the currently loaded vCPU is
in-kernel
- Harden against underflowing the active mmu_notifier invalidation
count, so that "bad" invalidations (usually due to bugs elsehwere
in the kernel) are detected earlier and are less likely to hang the
kernel
x86 Xen emulation:
- Overlay pages can now be cached based on host virtual address,
instead of guest physical addresses. This removes the need to
reconfigure and invalidate the cache if the guest changes the gpa
but the underlying host virtual address remains the same
- When possible, use a single host TSC value when computing the
deadline for Xen timers in order to improve the accuracy of the
timer emulation
- Inject pending upcall events when the vCPU software-enables its
APIC to fix a bug where an upcall can be lost (and to follow Xen's
behavior)
- Fall back to the slow path instead of warning if "fast" IRQ
delivery of Xen events fails, e.g. if the guest has aliased xAPIC
IDs
RISC-V:
- Support exception and interrupt handling in selftests
- New self test for RISC-V architectural timer (Sstc extension)
- New extension support (Ztso, Zacas)
- Support userspace emulation of random number seed CSRs
ARM:
- Infrastructure for building KVM's trap configuration based on the
architectural features (or lack thereof) advertised in the VM's ID
registers
- Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
x86's WC) at stage-2, improving the performance of interacting with
assigned devices that can tolerate it
- Conversion of KVM's representation of LPIs to an xarray, utilized
to address serialization some of the serialization on the LPI
injection path
- Support for _architectural_ VHE-only systems, advertised through
the absence of FEAT_E2H0 in the CPU's ID register
- Miscellaneous cleanups, fixes, and spelling corrections to KVM and
selftests
LoongArch:
- Set reserved bits as zero in CPUCFG
- Start SW timer only when vcpu is blocking
- Do not restart SW timer when it is expired
- Remove unnecessary CSR register saving during enter guest
- Misc cleanups and fixes as usual
Generic:
- Clean up Kconfig by removing CONFIG_HAVE_KVM, which was basically
always true on all architectures except MIPS (where Kconfig
determines the available depending on CPU capabilities). It is
replaced either by an architecture-dependent symbol for MIPS, and
IS_ENABLED(CONFIG_KVM) everywhere else
- Factor common "select" statements in common code instead of
requiring each architecture to specify it
- Remove thoroughly obsolete APIs from the uapi headers
- Move architecture-dependent stuff to uapi/asm/kvm.h
- Always flush the async page fault workqueue when a work item is
being removed, especially during vCPU destruction, to ensure that
there are no workers running in KVM code when all references to
KVM-the-module are gone, i.e. to prevent a very unlikely
use-after-free if kvm.ko is unloaded
- Grab a reference to the VM's mm_struct in the async #PF worker
itself instead of gifting the worker a reference, so that there's
no need to remember to *conditionally* clean up after the worker
Selftests:
- Reduce boilerplate especially when utilize selftest TAP
infrastructure
- Add basic smoke tests for SEV and SEV-ES, along with a pile of
library support for handling private/encrypted/protected memory
- Fix benign bugs where tests neglect to close() guest_memfd files"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (246 commits)
selftests: kvm: remove meaningless assignments in Makefiles
KVM: riscv: selftests: Add Zacas extension to get-reg-list test
RISC-V: KVM: Allow Zacas extension for Guest/VM
KVM: riscv: selftests: Add Ztso extension to get-reg-list test
RISC-V: KVM: Allow Ztso extension for Guest/VM
RISC-V: KVM: Forward SEED CSR access to user space
KVM: riscv: selftests: Add sstc timer test
KVM: riscv: selftests: Change vcpu_has_ext to a common function
KVM: riscv: selftests: Add guest helper to get vcpu id
KVM: riscv: selftests: Add exception handling support
LoongArch: KVM: Remove unnecessary CSR register saving during enter guest
LoongArch: KVM: Do not restart SW timer when it is expired
LoongArch: KVM: Start SW timer only when vcpu is blocking
LoongArch: KVM: Set reserved bits as zero in CPUCFG
KVM: selftests: Explicitly close guest_memfd files in some gmem tests
KVM: x86/xen: fix recursive deadlock in timer injection
KVM: pfncache: simplify locking and make more self-contained
KVM: x86/xen: remove WARN_ON_ONCE() with false positives in evtchn delivery
KVM: x86/xen: inject vCPU upcall vector when local APIC is enabled
KVM: x86/xen: improve accuracy of Xen timers
...
Pull non-MM updates from Andrew Morton:
- Kuan-Wei Chiu has developed the well-named series "lib min_heap: Min
heap optimizations".
- Kuan-Wei Chiu has also sped up the library sorting code in the series
"lib/sort: Optimize the number of swaps and comparisons".
- Alexey Gladkov has added the ability for code running within an IPC
namespace to alter its IPC and MQ limits. The series is "Allow to
change ipc/mq sysctls inside ipc namespace".
- Geert Uytterhoeven has contributed some dhrystone maintenance work in
the series "lib: dhry: miscellaneous cleanups".
- Ryusuke Konishi continues nilfs2 maintenance work in the series
"nilfs2: eliminate kmap and kmap_atomic calls"
"nilfs2: fix kernel bug at submit_bh_wbc()"
- Nathan Chancellor has updated our build tools requirements in the
series "Bump the minimum supported version of LLVM to 13.0.1".
- Muhammad Usama Anjum continues with the selftests maintenance work in
the series "selftests/mm: Improve run_vmtests.sh".
- Oleg Nesterov has done some maintenance work against the signal code
in the series "get_signal: minor cleanups and fix".
Plus the usual shower of singleton patches in various parts of the tree.
Please see the individual changelogs for details.
* tag 'mm-nonmm-stable-2024-03-14-09-36' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (77 commits)
nilfs2: prevent kernel bug at submit_bh_wbc()
nilfs2: fix failure to detect DAT corruption in btree and direct mappings
ocfs2: enable ocfs2_listxattr for special files
ocfs2: remove SLAB_MEM_SPREAD flag usage
assoc_array: fix the return value in assoc_array_insert_mid_shortcut()
buildid: use kmap_local_page()
watchdog/core: remove sysctl handlers from public header
nilfs2: use div64_ul() instead of do_div()
mul_u64_u64_div_u64: increase precision by conditionally swapping a and b
kexec: copy only happens before uchunk goes to zero
get_signal: don't initialize ksig->info if SIGNAL_GROUP_EXIT/group_exec_task
get_signal: hide_si_addr_tag_bits: fix the usage of uninitialized ksig
get_signal: don't abuse ksig->info.si_signo and ksig->sig
const_structs.checkpatch: add device_type
Normalise "name (ad@dr)" MODULE_AUTHORs to "name <ad@dr>"
dyndbg: replace kstrdup() + strchr() with kstrdup_and_replace()
list: leverage list_is_head() for list_entry_is_head()
nilfs2: MAINTAINERS: drop unreachable project mirror site
smp: make __smp_processor_id() 0-argument macro
fat: fix uninitialized field in nostale filehandles
...
Pull MM updates from Andrew Morton:
- Sumanth Korikkar has taught s390 to allocate hotplug-time page frames
from hotplugged memory rather than only from main memory. Series
"implement "memmap on memory" feature on s390".
- More folio conversions from Matthew Wilcox in the series
"Convert memcontrol charge moving to use folios"
"mm: convert mm counter to take a folio"
- Chengming Zhou has optimized zswap's rbtree locking, providing
significant reductions in system time and modest but measurable
reductions in overall runtimes. The series is "mm/zswap: optimize the
scalability of zswap rb-tree".
- Chengming Zhou has also provided the series "mm/zswap: optimize zswap
lru list" which provides measurable runtime benefits in some
swap-intensive situations.
- And Chengming Zhou further optimizes zswap in the series "mm/zswap:
optimize for dynamic zswap_pools". Measured improvements are modest.
- zswap cleanups and simplifications from Yosry Ahmed in the series
"mm: zswap: simplify zswap_swapoff()".
- In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has
contributed several DAX cleanups as well as adding a sysfs tunable to
control the memmap_on_memory setting when the dax device is
hotplugged as system memory.
- Johannes Weiner has added the large series "mm: zswap: cleanups",
which does that.
- More DAMON work from SeongJae Park in the series
"mm/damon: make DAMON debugfs interface deprecation unignorable"
"selftests/damon: add more tests for core functionalities and corner cases"
"Docs/mm/damon: misc readability improvements"
"mm/damon: let DAMOS feeds and tame/auto-tune itself"
- In the series "mm/mempolicy: weighted interleave mempolicy and sysfs
extension" Rakie Kim has developed a new mempolicy interleaving
policy wherein we allocate memory across nodes in a weighted fashion
rather than uniformly. This is beneficial in heterogeneous memory
environments appearing with CXL.
- Christophe Leroy has contributed some cleanup and consolidation work
against the ARM pagetable dumping code in the series "mm: ptdump:
Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute".
- Luis Chamberlain has added some additional xarray selftesting in the
series "test_xarray: advanced API multi-index tests".
- Muhammad Usama Anjum has reworked the selftest code to make its
human-readable output conform to the TAP ("Test Anything Protocol")
format. Amongst other things, this opens up the use of third-party
tools to parse and process out selftesting results.
- Ryan Roberts has added fork()-time PTE batching of THP ptes in the
series "mm/memory: optimize fork() with PTE-mapped THP". Mainly
targeted at arm64, this significantly speeds up fork() when the
process has a large number of pte-mapped folios.
- David Hildenbrand also gets in on the THP pte batching game in his
series "mm/memory: optimize unmap/zap with PTE-mapped THP". It
implements batching during munmap() and other pte teardown
situations. The microbenchmark improvements are nice.
- And in the series "Transparent Contiguous PTEs for User Mappings"
Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte
mappings"). Kernel build times on arm64 improved nicely. Ryan's
series "Address some contpte nits" provides some followup work.
- In the series "mm/hugetlb: Restore the reservation" Breno Leitao has
fixed an obscure hugetlb race which was causing unnecessary page
faults. He has also added a reproducer under the selftest code.
- In the series "selftests/mm: Output cleanups for the compaction
test", Mark Brown did what the title claims.
- Kinsey Ho has added the series "mm/mglru: code cleanup and
refactoring".
- Even more zswap material from Nhat Pham. The series "fix and extend
zswap kselftests" does as claimed.
- In the series "Introduce cpu_dcache_is_aliasing() to fix DAX
regression" Mathieu Desnoyers has cleaned up and fixed rather a mess
in our handling of DAX on archiecctures which have virtually aliasing
data caches. The arm architecture is the main beneficiary.
- Lokesh Gidra's series "per-vma locks in userfaultfd" provides
dramatic improvements in worst-case mmap_lock hold times during
certain userfaultfd operations.
- Some page_owner enhancements and maintenance work from Oscar Salvador
in his series
"page_owner: print stacks and their outstanding allocations"
"page_owner: Fixup and cleanup"
- Uladzislau Rezki has contributed some vmalloc scalability
improvements in his series "Mitigate a vmap lock contention". It
realizes a 12x improvement for a certain microbenchmark.
- Some kexec/crash cleanup work from Baoquan He in the series "Split
crash out from kexec and clean up related config items".
- Some zsmalloc maintenance work from Chengming Zhou in the series
"mm/zsmalloc: fix and optimize objects/page migration"
"mm/zsmalloc: some cleanup for get/set_zspage_mapping()"
- Zi Yan has taught the MM to perform compaction on folios larger than
order=0. This a step along the path to implementaton of the merging
of large anonymous folios. The series is named "Enable >0 order folio
memory compaction".
- Christoph Hellwig has done quite a lot of cleanup work in the
pagecache writeback code in his series "convert write_cache_pages()
to an iterator".
- Some modest hugetlb cleanups and speedups in Vishal Moola's series
"Handle hugetlb faults under the VMA lock".
- Zi Yan has changed the page splitting code so we can split huge pages
into sizes other than order-0 to better utilize large folios. The
series is named "Split a folio to any lower order folios".
- David Hildenbrand has contributed the series "mm: remove
total_mapcount()", a cleanup.
- Matthew Wilcox has sought to improve the performance of bulk memory
freeing in his series "Rearrange batched folio freeing".
- Gang Li's series "hugetlb: parallelize hugetlb page init on boot"
provides large improvements in bootup times on large machines which
are configured to use large numbers of hugetlb pages.
- Matthew Wilcox's series "PageFlags cleanups" does that.
- Qi Zheng's series "minor fixes and supplement for ptdesc" does that
also. S390 is affected.
- Cleanups to our pagemap utility functions from Peter Xu in his series
"mm/treewide: Replace pXd_large() with pXd_leaf()".
- Nico Pache has fixed a few things with our hugepage selftests in his
series "selftests/mm: Improve Hugepage Test Handling in MM
Selftests".
- Also, of course, many singleton patches to many things. Please see
the individual changelogs for details.
* tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits)
mm/zswap: remove the memcpy if acomp is not sleepable
crypto: introduce: acomp_is_async to expose if comp drivers might sleep
memtest: use {READ,WRITE}_ONCE in memory scanning
mm: prohibit the last subpage from reusing the entire large folio
mm: recover pud_leaf() definitions in nopmd case
selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements
selftests/mm: skip uffd hugetlb tests with insufficient hugepages
selftests/mm: dont fail testsuite due to a lack of hugepages
mm/huge_memory: skip invalid debugfs new_order input for folio split
mm/huge_memory: check new folio order when split a folio
mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure
mm: add an explicit smp_wmb() to UFFDIO_CONTINUE
mm: fix list corruption in put_pages_list
mm: remove folio from deferred split list before uncharging it
filemap: avoid unnecessary major faults in filemap_fault()
mm,page_owner: drop unnecessary check
mm,page_owner: check for null stack_record before bumping its refcount
mm: swap: fix race between free_swap_and_cache() and swapoff()
mm/treewide: align up pXd_leaf() retval across archs
mm/treewide: drop pXd_large()
...
KVM/arm64 updates for 6.9
- Infrastructure for building KVM's trap configuration based on the
architectural features (or lack thereof) advertised in the VM's ID
registers
- Support for mapping vfio-pci BARs as Normal-NC (vaguely similar to
x86's WC) at stage-2, improving the performance of interacting with
assigned devices that can tolerate it
- Conversion of KVM's representation of LPIs to an xarray, utilized to
address serialization some of the serialization on the LPI injection
path
- Support for _architectural_ VHE-only systems, advertised through the
absence of FEAT_E2H0 in the CPU's ID register
- Miscellaneous cleanups, fixes, and spelling corrections to KVM and
selftests
LoongArch KVM changes for v6.9
* Set reserved bits as zero in CPUCFG.
* Start SW timer only when vcpu is blocking.
* Do not restart SW timer when it is expired.
* Remove unnecessary CSR register saving during enter guest.
The general expectation with debugfs is that any initialization failure
is nonfatal. Nevertheless, kvm_arch_create_vm_debugfs() allows
implementations to return an error and kvm_create_vm_debugfs() allows
that to fail VM creation.
Change to a void return to discourage architectures from making debugfs
failures fatal for the VM. Seems like everyone already had the right
idea, as all implementations already return 0 unconditionally.
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20240216155941.2029458-1-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Add CPU table entries for raw and architected mode. Most fields are
copied from the Power10 table entries.
CPU, MMU and user (ELF_HWCAP) features are unchanged vs P10. However
userspace can detect P11 because the AT_PLATFORM value changes to
"power11".
The logical PVR value of 0x0F000007, passed to firmware via the
ibm_arch_vec, indicates the kernel can support a P11 compatible CPU,
which means at least ISA v3.1 compliant.
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240221044623.1598642-1-mpe@ellerman.id.au
Currently, rebooting a pseries nested qemu-kvm guest (L2) results in
below error as L1 qemu sends PVR value 'arch_compat' == 0 via
ppc_set_compat ioctl. This triggers a condition failure in
kvmppc_set_arch_compat() resulting in an EINVAL.
qemu-system-ppc64: Unable to set CPU compatibility mode in KVM: Invalid
argument
Also, a value of 0 for arch_compat generally refers the default
compatibility of the host. But, arch_compat, being a Guest Wide Element
in nested API v2, cannot be set to 0 in GSB as PowerVM (L0) expects a
non-zero value. A value of 0 triggers a kernel trap during a reboot and
consequently causes it to fail:
[ 22.106360] reboot: Restarting system
KVM: unknown exit, hardware reason ffffffffffffffea
NIP 0000000000000100 LR 000000000000fe44 CTR 0000000000000000 XER 0000000020040092 CPU#0
MSR 0000000000001000 HID0 0000000000000000 HF 6c000000 iidx 3 didx 3
TB 00000000 00000000 DECR 0
GPR00 0000000000000000 0000000000000000 c000000002a8c300 000000007fe00000
GPR04 0000000000000000 0000000000000000 0000000000001002 8000000002803033
GPR08 000000000a000000 0000000000000000 0000000000000004 000000002fff0000
GPR12 0000000000000000 c000000002e10000 0000000105639200 0000000000000004
GPR16 0000000000000000 000000010563a090 0000000000000000 0000000000000000
GPR20 0000000105639e20 00000001056399c8 00007fffe54abab0 0000000105639288
GPR24 0000000000000000 0000000000000001 0000000000000001 0000000000000000
GPR28 0000000000000000 0000000000000000 c000000002b30840 0000000000000000
CR 00000000 [ - - - - - - - - ] RES 000@ffffffffffffffff
SRR0 0000000000000000 SRR1 0000000000000000 PVR 0000000000800200 VRSAVE 0000000000000000
SPRG0 0000000000000000 SPRG1 0000000000000000 SPRG2 0000000000000000 SPRG3 0000000000000000
SPRG4 0000000000000000 SPRG5 0000000000000000 SPRG6 0000000000000000 SPRG7 0000000000000000
HSRR0 0000000000000000 HSRR1 0000000000000000
CFAR 0000000000000000
LPCR 0000000000020400
PTCR 0000000000000000 DAR 0000000000000000 DSISR 0000000000000000
kernel:trap=0xffffffea | pc=0x100 | msr=0x1000
This patch updates kvmppc_set_arch_compat() to use the host PVR value if
'compat_pvr' == 0 indicating that qemu doesn't want to enforce any
specific PVR compat mode.
The relevant part of the code might need a rework if PowerVM implements
a support for `arch_compat == 0` in nestedv2 API.
Fixes: 19d31c5f11 ("KVM: PPC: Add support for nestedv2 guests")
Reviewed-by: "Aneesh Kumar K.V (IBM)" <aneesh.kumar@kernel.org>
Reviewed-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240207054526.3720087-1-amachhiw@linux.ibm.com
CONFIG_IRQ_BYPASS_MANAGER is a dependency of the common code included by
CONFIG_HAVE_KVM_IRQ_BYPASS. There is no advantage in adding the corresponding
"select" directive to each architecture.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull kvm updates from Paolo Bonzini:
"Generic:
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all
architectures.
- Clean up Kconfigs that all KVM architectures were selecting
- New functionality around "guest_memfd", a new userspace API that
creates an anonymous file and returns a file descriptor that refers
to it. guest_memfd files are bound to their owning virtual machine,
cannot be mapped, read, or written by userspace, and cannot be
resized. guest_memfd files do however support PUNCH_HOLE, which can
be used to switch a memory area between guest_memfd and regular
anonymous memory.
- New ioctl KVM_SET_MEMORY_ATTRIBUTES allowing userspace to specify
per-page attributes for a given page of guest memory; right now the
only attribute is whether the guest expects to access memory via
guest_memfd or not, which in Confidential SVMs backed by SEV-SNP,
TDX or ARM64 pKVM is checked by firmware or hypervisor that
guarantees confidentiality (AMD PSP, Intel TDX module, or EL2 in
the case of pKVM).
x86:
- Support for "software-protected VMs" that can use the new
guest_memfd and page attributes infrastructure. This is mostly
useful for testing, since there is no pKVM-like infrastructure to
provide a meaningfully reduced TCB.
- Fix a relatively benign off-by-one error when splitting huge pages
during CLEAR_DIRTY_LOG.
- Fix a bug where KVM could incorrectly test-and-clear dirty bits in
non-leaf TDP MMU SPTEs if a racing thread replaces a huge SPTE with
a non-huge SPTE.
- Use more generic lockdep assertions in paths that don't actually
care about whether the caller is a reader or a writer.
- let Xen guests opt out of having PV clock reported as "based on a
stable TSC", because some of them don't expect the "TSC stable" bit
(added to the pvclock ABI by KVM, but never set by Xen) to be set.
- Revert a bogus, made-up nested SVM consistency check for
TLB_CONTROL.
- Advertise flush-by-ASID support for nSVM unconditionally, as KVM
always flushes on nested transitions, i.e. always satisfies flush
requests. This allows running bleeding edge versions of VMware
Workstation on top of KVM.
- Sanity check that the CPU supports flush-by-ASID when enabling SEV
support.
- On AMD machines with vNMI, always rely on hardware instead of
intercepting IRET in some cases to detect unmasking of NMIs
- Support for virtualizing Linear Address Masking (LAM)
- Fix a variety of vPMU bugs where KVM fail to stop/reset counters
and other state prior to refreshing the vPMU model.
- Fix a double-overflow PMU bug by tracking emulated counter events
using a dedicated field instead of snapshotting the "previous"
counter. If the hardware PMC count triggers overflow that is
recognized in the same VM-Exit that KVM manually bumps an event
count, KVM would pend PMIs for both the hardware-triggered overflow
and for KVM-triggered overflow.
- Turn off KVM_WERROR by default for all configs so that it's not
inadvertantly enabled by non-KVM developers, which can be
problematic for subsystems that require no regressions for W=1
builds.
- Advertise all of the host-supported CPUID bits that enumerate
IA32_SPEC_CTRL "features".
- Don't force a masterclock update when a vCPU synchronizes to the
current TSC generation, as updating the masterclock can cause
kvmclock's time to "jump" unexpectedly, e.g. when userspace
hotplugs a pre-created vCPU.
- Use RIP-relative address to read kvm_rebooting in the VM-Enter
fault paths, partly as a super minor optimization, but mostly to
make KVM play nice with position independent executable builds.
- Guard KVM-on-HyperV's range-based TLB flush hooks with an #ifdef on
CONFIG_HYPERV as a minor optimization, and to self-document the
code.
- Add CONFIG_KVM_HYPERV to allow disabling KVM support for HyperV
"emulation" at build time.
ARM64:
- LPA2 support, adding 52bit IPA/PA capability for 4kB and 16kB base
granule sizes. Branch shared with the arm64 tree.
- Large Fine-Grained Trap rework, bringing some sanity to the
feature, although there is more to come. This comes with a prefix
branch shared with the arm64 tree.
- Some additional Nested Virtualization groundwork, mostly
introducing the NV2 VNCR support and retargetting the NV support to
that version of the architecture.
- A small set of vgic fixes and associated cleanups.
Loongarch:
- Optimization for memslot hugepage checking
- Cleanup and fix some HW/SW timer issues
- Add LSX/LASX (128bit/256bit SIMD) support
RISC-V:
- KVM_GET_REG_LIST improvement for vector registers
- Generate ISA extension reg_list using macros in get-reg-list
selftest
- Support for reporting steal time along with selftest
s390:
- Bugfixes
Selftests:
- Fix an annoying goof where the NX hugepage test prints out garbage
instead of the magic token needed to run the test.
- Fix build errors when a header is delete/moved due to a missing
flag in the Makefile.
- Detect if KVM bugged/killed a selftest's VM and print out a helpful
message instead of complaining that a random ioctl() failed.
- Annotate the guest printf/assert helpers with __printf(), and fix
the various bugs that were lurking due to lack of said annotation"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (185 commits)
x86/kvm: Do not try to disable kvmclock if it was not enabled
KVM: x86: add missing "depends on KVM"
KVM: fix direction of dependency on MMU notifiers
KVM: introduce CONFIG_KVM_COMMON
KVM: arm64: Add missing memory barriers when switching to pKVM's hyp pgd
KVM: arm64: vgic-its: Avoid potential UAF in LPI translation cache
RISC-V: KVM: selftests: Add get-reg-list test for STA registers
RISC-V: KVM: selftests: Add steal_time test support
RISC-V: KVM: selftests: Add guest_sbi_probe_extension
RISC-V: KVM: selftests: Move sbi_ecall to processor.c
RISC-V: KVM: Implement SBI STA extension
RISC-V: KVM: Add support for SBI STA registers
RISC-V: KVM: Add support for SBI extension registers
RISC-V: KVM: Add SBI STA info to vcpu_arch
RISC-V: KVM: Add steal-update vcpu request
RISC-V: KVM: Add SBI STA extension skeleton
RISC-V: paravirt: Implement steal-time support
RISC-V: Add SBI STA extension definitions
RISC-V: paravirt: Add skeleton for pv-time support
RISC-V: KVM: Fix indentation in kvm_riscv_vcpu_set_reg_csr()
...
Pull header cleanups from Kent Overstreet:
"The goal is to get sched.h down to a type only header, so the main
thing happening in this patchset is splitting out various _types.h
headers and dependency fixups, as well as moving some things out of
sched.h to better locations.
This is prep work for the memory allocation profiling patchset which
adds new sched.h interdepencencies"
* tag 'header_cleanup-2024-01-10' of https://evilpiepirate.org/git/bcachefs: (51 commits)
Kill sched.h dependency on rcupdate.h
kill unnecessary thread_info.h include
Kill unnecessary kernel.h include
preempt.h: Kill dependency on list.h
rseq: Split out rseq.h from sched.h
LoongArch: signal.c: add header file to fix build error
restart_block: Trim includes
lockdep: move held_lock to lockdep_types.h
sem: Split out sem_types.h
uidgid: Split out uidgid_types.h
seccomp: Split out seccomp_types.h
refcount: Split out refcount_types.h
uapi/linux/resource.h: fix include
x86/signal: kill dependency on time.h
syscall_user_dispatch.h: split out *_types.h
mm_types_task.h: Trim dependencies
Split out irqflags_types.h
ipc: Kill bogus dependency on spinlock.h
shm: Slim down dependencies
workqueue: Split out workqueue_types.h
...
Common KVM changes for 6.8:
- Use memdup_array_user() to harden against overflow.
- Unconditionally advertise KVM_CAP_DEVICE_CTRL for all architectures.
CONFIG_HAVE_KVM is currently used by some architectures to either
enabled the KVM config proper, or to enable host-side code that is
not part of the KVM module. However, CONFIG_KVM's "select" statement
in virt/kvm/Kconfig corresponds to a third meaning, namely to
enable common Kconfigs required by all architectures that support
KVM.
These three meanings can be replaced respectively by an
architecture-specific Kconfig, by IS_ENABLED(CONFIG_KVM), or by
a new Kconfig symbol that is in turn selected by the
architecture-specific "config KVM".
Start by introducing such a new Kconfig symbol, CONFIG_KVM_COMMON.
Unlike CONFIG_HAVE_KVM, it is selected by CONFIG_KVM, not by
architecture code, and it brings in all dependencies of common
KVM code. In particular, INTERVAL_TREE was missing in loongarch
and riscv, so that is another thing that is fixed.
Fixes: 8132d887a7 ("KVM: remove CONFIG_HAVE_KVM_EVENTFD", 2023-12-08)
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Closes: https://lore.kernel.org/all/44907c6b-c5bd-4e4a-a921-e4d3825539d8@infradead.org/
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
by moving cond_resched_rcu() to rcupdate_wait.h, we can kill another big
sched.h dependency.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
All platforms with a kernel irqchip have support for irqfd. Unify the
two configuration items so that userspace can expect to use irqfd to
inject interrupts into the irqchip.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
virt/kvm/eventfd.c is compiled unconditionally, meaning that the ioeventfds
member of struct kvm is accessed unconditionally. CONFIG_HAVE_KVM_EVENTFD
therefore must be defined for KVM common code to compile successfully,
remove it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In the nestedv2 case, if there is a pending decrementer exception, the
L1 must get the L2's timebase from the L0 to see if the exception should
be cancelled. This adds the overhead of a H_GUEST_GET_STATE call to the
likely case in which the decrementer should not be cancelled.
Avoid this logic for the nestedv2 case.
Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231201132618.555031-13-vaibhav@linux.ibm.com
