Commit Graph

835 Commits

Author SHA1 Message Date
Heiko Carstens
fd2527f209 s390/fpu: move, rename, and merge header files
Move, rename, and merge the fpu and vx header files. This way fpu header
files have a consistent naming scheme (fpu*.h).

Also get rid of the fpu subdirectory and move header files to asm
directory, so that all fpu and vx header files can be found at the same
location.

Merge internal.h header file into other header files, since the internal
helpers are used at many locations. so those helper functions are really
not internal.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-02-16 14:30:14 +01:00
Alexander Gordeev
7b2411e793 KVM: s390: fix virtual vs physical address confusion
Fix virtual vs physical address confusion. This does not fix a bug
since virtual and physical address spaces are currently the same.

Suggested-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Anthony Krowiak <akrowiak@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2024-02-14 16:25:29 +01:00
Heiko Carstens
304103736b s390/acrs: cleanup access register handling
save_access_regs() and restore_access_regs() are only available by
including switch_to.h. This is done by a couple of C files, which have
nothing to do with switch_to(), but only need these functions.

Move both functions to a new header file and improve the implementation:

- Get rid of typedef

- Add memory access instrumentation support

- Use long displacement instructions lamy/stamy instead of lam/stam - all
  current users end up with better code because of this

Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2024-02-12 15:03:33 +01:00
Linus Torvalds
09d1c6a80f Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
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()
  ...
2024-01-17 13:03:37 -08:00
Heiko Carstens
18564756ab s390/fpu: get rid of MACHINE_HAS_VX
Get rid of MACHINE_HAS_VX and replace it with cpu_has_vx() which is a
short readable wrapper for "test_facility(129)".

Facility bit 129 is set if the vector facility is present. test_facility()
returns also true for all bits which are set in the architecture level set
of the cpu that the kernel is compiled for. This means that
test_facility(129) is a compile time constant which returns true for z13
and later, since the vector facility bit is part of the z13 kernel ALS.

In result the compiled code will have less runtime checks, and less code.

Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2023-12-11 14:33:07 +01:00
Heiko Carstens
d7271ba401 KVM: s390: remove superfluous save_fpu_regs() call
The save_fpu_regs() call in kvm_arch_vcpu_ioctl_get_fpu() is pointless: it
will save the current user space fpu context to the thread's save area. But
the code is accessing only the vcpu's save are / mapped register area,
which in this case are not the same.

Therefore remove the confusing call.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2023-12-11 14:33:06 +01:00
Heiko Carstens
702644249d s390/fpu: get rid of test_fp_ctl()
It is quite subtle to use test_fp_ctl() correctly. Therefore remove it -
instead copy whatever new floating point control (fpc) register values are
supposed to be used into its save area.

Test the validity of the new value when loading it. If the new value is
invalid, load the fpc register with zero.

This seems to be a the best way to approach this problem. Even though this
changes behavior:

- sigreturn with an invalid fpc value on the stack will succeed, and
  continue with zero value, instead of returning with SIGSEGV

- ptraced processes will also use a zero value instead of letting the
  request fail with -EINVAL

However all of this seems to acceptable. After all testing of the value was
only implemented to avoid that user space can crash the kernel. It is not
there to test values for validity; and the assumption is that there is no
existing user space which is doing this.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2023-12-11 14:33:06 +01:00
Heiko Carstens
3b2e00f167 KVM: s390: use READ_ONCE() to read fpc register value
Use READ_ONCE() to read a vcpu's floating point register value from
the memory mapped area. This avoids that, depending on code
generation, a different value is tested for validity than the one that
is used, since user space can modify the area concurrently and the
compiler is free to generate code that reads the value multiple times.

Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2023-12-11 14:33:05 +01:00
Heiko Carstens
b988b1bb00 KVM: s390: fix setting of fpc register
kvm_arch_vcpu_ioctl_set_fpu() allows to set the floating point control
(fpc) register of a guest cpu. The new value is tested for validity by
temporarily loading it into the fpc register.

This may lead to corruption of the fpc register of the host process:
if an interrupt happens while the value is temporarily loaded into the fpc
register, and within interrupt context floating point or vector registers
are used, the current fp/vx registers are saved with save_fpu_regs()
assuming they belong to user space and will be loaded into fp/vx registers
when returning to user space.

test_fp_ctl() restores the original user space / host process fpc register
value, however it will be discarded, when returning to user space.

In result the host process will incorrectly continue to run with the value
that was supposed to be used for a guest cpu.

Fix this by simply removing the test. There is another test right before
the SIE context is entered which will handles invalid values.

This results in a change of behaviour: invalid values will now be accepted
instead of that the ioctl fails with -EINVAL. This seems to be acceptable,
given that this interface is most likely not used anymore, and this is in
addition the same behaviour implemented with the memory mapped interface
(replace invalid values with zero) - see sync_regs() in kvm-s390.c.

Reviewed-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2023-12-11 14:33:05 +01:00
Wei Wang
63912245c1 KVM: move KVM_CAP_DEVICE_CTRL to the generic check
KVM_CAP_DEVICE_CTRL allows userspace to check if the kvm_device
framework (e.g. KVM_CREATE_DEVICE) is supported by KVM. Move
KVM_CAP_DEVICE_CTRL to the generic check for the two reasons:
1) it already supports arch agnostic usages (i.e. KVM_DEV_TYPE_VFIO).
For example, userspace VFIO implementation may needs to create
KVM_DEV_TYPE_VFIO on x86, riscv, or arm etc. It is simpler to have it
checked at the generic code than at each arch's code.
2) KVM_CREATE_DEVICE has been added to the generic code.

Link: https://lore.kernel.org/all/20221215115207.14784-1-wei.w.wang@intel.com
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Acked-by: Anup Patel <anup@brainfault.org> (riscv)
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Link: https://lore.kernel.org/r/20230315101606.10636-1-wei.w.wang@intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
2023-11-30 13:09:43 -08:00
Linus Torvalds
e392ea4d4d Merge tag 's390-6.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Vasily Gorbik:

 - Get rid of private VM_FAULT flags

 - Add word-at-a-time implementation

 - Add DCACHE_WORD_ACCESS support

 - Cleanup control register handling

 - Disallow CPU hotplug of CPU 0 to simplify its handling complexity,
   following a similar restriction in x86

 - Optimize pai crypto map allocation

 - Update the list of crypto express EP11 coprocessor operation modes

 - Fixes and improvements for secure guests AP pass-through

 - Several fixes to address incorrect page marking for address
   translation with the "cmma no-dat" feature, preventing potential
   incorrect guest TLB flushes

 - Fix early IPI handling

 - Several virtual vs physical address confusion fixes

 - Various small fixes and improvements all over the code

* tag 's390-6.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (74 commits)
  s390/cio: replace deprecated strncpy with strscpy
  s390/sclp: replace deprecated strncpy with strtomem
  s390/cio: fix virtual vs physical address confusion
  s390/cio: export CMG value as decimal
  s390: delete the unused store_prefix() function
  s390/cmma: fix handling of swapper_pg_dir and invalid_pg_dir
  s390/cmma: fix detection of DAT pages
  s390/sclp: handle default case in sclp memory notifier
  s390/pai_crypto: remove per-cpu variable assignement in event initialization
  s390/pai: initialize event count once at initialization
  s390/pai_crypto: use PERF_ATTACH_TASK define for per task detection
  s390/mm: add missing arch_set_page_dat() call to gmap allocations
  s390/mm: add missing arch_set_page_dat() call to vmem_crst_alloc()
  s390/cmma: fix initial kernel address space page table walk
  s390/diag: add missing virt_to_phys() translation to diag224()
  s390/mm,fault: move VM_FAULT_ERROR handling to do_exception()
  s390/mm,fault: remove VM_FAULT_BADMAP and VM_FAULT_BADACCESS
  s390/mm,fault: remove VM_FAULT_SIGNAL
  s390/mm,fault: remove VM_FAULT_BADCONTEXT
  s390/mm,fault: simplify kfence fault handling
  ...
2023-11-03 10:17:22 -10:00
Nico Boehr
70fea30195 KVM: s390: add tracepoint in gmap notifier
The gmap notifier is called for changes in table entries with the
notifier bit set. To diagnose performance issues, it can be useful to
see what causes certain changes in the gmap.

Hence, add a tracepoint in the gmap notifier.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20231009093304.2555344-3-nrb@linux.ibm.com
Message-Id: <20231009093304.2555344-3-nrb@linux.ibm.com>
2023-10-16 14:54:29 +02:00
Nico Boehr
c3235e2dd6 KVM: s390: add stat counter for shadow gmap events
The shadow gmap tracks memory of nested guests (guest-3). In certain
scenarios, the shadow gmap needs to be rebuilt, which is a costly operation
since it involves a SIE exit into guest-1 for every entry in the respective
shadow level.

Add kvm stat counters when new shadow structures are created at various
levels. Also add a counter gmap_shadow_create when a completely fresh
shadow gmap is created as well as a counter gmap_shadow_reuse when an
existing gmap is being reused.

Note that when several levels are shadowed at once, counters on all
affected levels will be increased.

Also note that not all page table levels need to be present and a ASCE
can directly point to e.g. a segment table. In this case, a new segment
table will always be equivalent to a new shadow gmap and hence will be
counted as gmap_shadow_create and not as gmap_shadow_segment.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20231009093304.2555344-2-nrb@linux.ibm.com
Message-Id: <20231009093304.2555344-2-nrb@linux.ibm.com>
2023-10-16 14:54:29 +02:00
Heiko Carstens
99441a38c3 s390: use control register bit defines
Use control register bit defines instead of plain numbers where
possible.

Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-09-19 13:26:57 +02:00
Heiko Carstens
8d5e98f8d6 s390/ctlreg: add local and system prefix to some functions
Add local and system prefix to some functions to clarify they change
control register contents on either the local CPU or the on all CPUs.

This results in the following API:

Two defines which load and save multiple control registers.
The defines correlate with the following C prototypes:

void __local_ctl_load(unsigned long *, unsigned int cr_low, unsigned int cr_high);
void __local_ctl_store(unsigned long *, unsigned int cr_low, unsigned int cr_high);

Two functions which locally set or clear one bit for a specified
control register:

void local_ctl_set_bit(unsigned int cr, unsigned int bit);
void local_ctl_clear_bit(unsigned int cr, unsigned int bit);

Two functions which set or clear one bit for a specified control
register on all CPUs:

void system_ctl_set_bit(unsigned int cr, unsigned int bit);
void system_ctl_clear_bit(unsigend int cr, unsigned int bit);

Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-09-19 13:26:56 +02:00
Steffen Eiden
19c654bf05 KVM: s390: Add UV feature negotiation
Add a uv_feature list for pv-guests to the KVM cpu-model.
The feature bits 'AP-interpretation for secure guests' and
'AP-interrupt for secure guests' are available.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20230815151415.379760-4-seiden@linux.ibm.com
Message-Id: <20230815151415.379760-4-seiden@linux.ibm.com>
2023-08-28 09:27:55 +00:00
Steffen Eiden
59a881402c s390/uv: UV feature check utility
Introduces a function to check the existence of an UV feature.
Refactor feature bit checks to use the new function.

Signed-off-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Michael Mueller <mimu@linux.ibm.com>
Link: https://lore.kernel.org/r/20230815151415.379760-3-seiden@linux.ibm.com
Message-Id: <20230815151415.379760-3-seiden@linux.ibm.com>
2023-08-28 09:27:55 +00:00
Ilya Leoshkevich
1ad1fa820e KVM: s390: interrupt: Fix single-stepping userspace-emulated instructions
Single-stepping a userspace-emulated instruction that generates an
interrupt causes GDB to land on the instruction following it instead of
the respective interrupt handler.

The reason is that after arranging a KVM_EXIT_S390_SIEIC exit,
kvm_handle_sie_intercept() calls kvm_s390_handle_per_ifetch_icpt(),
which sets KVM_GUESTDBG_EXIT_PENDING. This bit, however, is not
processed immediately, but rather persists until the next ioctl(),
causing a spurious single-step exit.

Fix by clearing this bit in ioctl().

Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20230725143857.228626-5-iii@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-08-28 09:24:20 +00:00
Ilya Leoshkevich
16631c42e6 KVM: s390: interrupt: Fix single-stepping into interrupt handlers
After single-stepping an instruction that generates an interrupt, GDB
ends up on the second instruction of the respective interrupt handler.

The reason is that vcpu_pre_run() manually delivers the interrupt, and
then __vcpu_run() runs the first handler instruction using the
CPUSTAT_P flag. This causes a KVM_SINGLESTEP exit on the second handler
instruction.

Fix by delaying the KVM_SINGLESTEP exit until after the manual
interrupt delivery.

Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Message-ID: <20230725143857.228626-2-iii@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-08-28 09:24:19 +00:00
Linus Torvalds
a452483508 Merge tag 's390-6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull more s390 updates from Alexander Gordeev:

 - Fix virtual vs physical address confusion in vmem_add_range() and
   vmem_remove_range() functions

 - Include <linux/io.h> instead of <asm/io.h> and <asm-generic/io.h>
   throughout s390 code

 - Make all PSW related defines also available for assembler files.
   Remove PSW_DEFAULT_KEY define from uapi for that

 - When adding an undefined symbol the build still succeeds, but
   userspace crashes trying to execute VDSO, because the symbol is not
   resolved. Add undefined symbols check to prevent that

 - Use kvmalloc_array() instead of kzalloc() for allocaton of 256k
   memory when executing s390 crypto adapter IOCTL

 - Add -fPIE flag to prevent decompressor misaligned symbol build error
   with clang

 - Use .balign instead of .align everywhere. This is a no-op for s390,
   but with this there no mix in using .align and .balign anymore

 - Filter out -mno-pic-data-is-text-relative flag when compiling kernel
   to prevent VDSO build error

 - Rework entering of DAT-on mode on CPU restart to use PSW_KERNEL_BITS
   mask directly

 - Do not retry administrative requests to some s390 crypto cards, since
   the firmware assumes replay attacks

 - Remove most of the debug code, which is build in when kernel config
   option CONFIG_ZCRYPT_DEBUG is enabled

 - Remove CONFIG_ZCRYPT_MULTIDEVNODES kernel config option and switch
   off the multiple devices support for the s390 zcrypt device driver

 - With the conversion to generic entry machine checks are accounted to
   the current context instead of irq time. As result, the STCKF
   instruction at the beginning of the machine check handler and the
   lowcore member are no longer required, therefore remove it

 - Fix various typos found with codespell

 - Minor cleanups to CPU-measurement Counter and Sampling Facilities
   code

 - Revert patch that removes VMEM_MAX_PHYS macro, since it causes a
   regression

* tag 's390-6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (25 commits)
  Revert "s390/mm: get rid of VMEM_MAX_PHYS macro"
  s390/cpum_sf: remove check on CPU being online
  s390/cpum_sf: handle casts consistently
  s390/cpum_sf: remove unnecessary debug statement
  s390/cpum_sf: remove parameter in call to pr_err
  s390/cpum_sf: simplify function setup_pmu_cpu
  s390/cpum_cf: remove unneeded debug statements
  s390/entry: remove mcck clock
  s390: fix various typos
  s390/zcrypt: remove ZCRYPT_MULTIDEVNODES kernel config option
  s390/zcrypt: do not retry administrative requests
  s390/zcrypt: cleanup some debug code
  s390/entry: rework entering DAT-on mode on CPU restart
  s390/mm: fence off VM macros from asm and linker
  s390: include linux/io.h instead of asm/io.h
  s390/ptrace: make all psw related defines also available for asm
  s390/ptrace: remove PSW_DEFAULT_KEY from uapi
  s390/vdso: filter out mno-pic-data-is-text-relative cflag
  s390: consistently use .balign instead of .align
  s390/decompressor: fix misaligned symbol build error
  ...
2023-07-06 13:18:30 -07:00
Heiko Carstens
cada938a01 s390: fix various typos
Fix various typos found with codespell.

Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
2023-07-03 11:19:42 +02:00
Nico Boehr
285cff4c04 KVM: s390: fix KVM_S390_GET_CMMA_BITS for GFNs in memslot holes
The KVM_S390_GET_CMMA_BITS ioctl may return incorrect values when userspace
specifies a start_gfn outside of memslots.

This can occur when a VM has multiple memslots with a hole in between:

+-----+----------+--------+--------+
| ... | Slot N-1 | <hole> | Slot N |
+-----+----------+--------+--------+
      ^          ^        ^        ^
      |          |        |        |
GFN   A          A+B      |        |
                          A+B+C    |
			           A+B+C+D

When userspace specifies a GFN in [A+B, A+B+C), it would expect to get the
CMMA values of the first dirty page in Slot N. However, userspace may get a
start_gfn of A+B+C+D with a count of 0, hence completely skipping over any
dirty pages in slot N.

The error is in kvm_s390_next_dirty_cmma(), which assumes
gfn_to_memslot_approx() will return the memslot _below_ the specified GFN
when the specified GFN lies outside a memslot. In reality it may return
either the memslot below or above the specified GFN.

When a memslot above the specified GFN is returned this happens:

- ofs is calculated, but since the memslot's base_gfn is larger than the
  specified cur_gfn, ofs will underflow to a huge number.
- ofs is passed to find_next_bit(). Since ofs will exceed the memslot's
  number of pages, the number of pages in the memslot is returned,
  completely skipping over all bits in the memslot userspace would be
  interested in.

Fix this by resetting ofs to zero when a memslot _above_ cur_gfn is
returned (cur_gfn < ms->base_gfn).

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Fixes: afdad61615 ("KVM: s390: Fix storage attributes migration with memory slots")
Message-Id: <20230324145424.293889-2-nrb@linux.ibm.com>
Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-06-13 11:25:35 +02:00
Linus Torvalds
c8c655c34e Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
 "s390:

   - More phys_to_virt conversions

   - Improvement of AP management for VSIE (nested virtualization)

  ARM64:

   - Numerous fixes for the pathological lock inversion issue that
     plagued KVM/arm64 since... forever.

   - New framework allowing SMCCC-compliant hypercalls to be forwarded
     to userspace, hopefully paving the way for some more features being
     moved to VMMs rather than be implemented in the kernel.

   - Large rework of the timer code to allow a VM-wide offset to be
     applied to both virtual and physical counters as well as a
     per-timer, per-vcpu offset that complements the global one. This
     last part allows the NV timer code to be implemented on top.

   - A small set of fixes to make sure that we don't change anything
     affecting the EL1&0 translation regime just after having having
     taken an exception to EL2 until we have executed a DSB. This
     ensures that speculative walks started in EL1&0 have completed.

   - The usual selftest fixes and improvements.

  x86:

   - Optimize CR0.WP toggling by avoiding an MMU reload when TDP is
     enabled, and by giving the guest control of CR0.WP when EPT is
     enabled on VMX (VMX-only because SVM doesn't support per-bit
     controls)

   - Add CR0/CR4 helpers to query single bits, and clean up related code
     where KVM was interpreting kvm_read_cr4_bits()'s "unsigned long"
     return as a bool

   - Move AMD_PSFD to cpufeatures.h and purge KVM's definition

   - Avoid unnecessary writes+flushes when the guest is only adding new
     PTEs

   - Overhaul .sync_page() and .invlpg() to utilize .sync_page()'s
     optimizations when emulating invalidations

   - Clean up the range-based flushing APIs

   - Revamp the TDP MMU's reaping of Accessed/Dirty bits to clear a
     single A/D bit using a LOCK AND instead of XCHG, and skip all of
     the "handle changed SPTE" overhead associated with writing the
     entire entry

   - Track the number of "tail" entries in a pte_list_desc to avoid
     having to walk (potentially) all descriptors during insertion and
     deletion, which gets quite expensive if the guest is spamming
     fork()

   - Disallow virtualizing legacy LBRs if architectural LBRs are
     available, the two are mutually exclusive in hardware

   - Disallow writes to immutable feature MSRs (notably
     PERF_CAPABILITIES) after KVM_RUN, similar to CPUID features

   - Overhaul the vmx_pmu_caps selftest to better validate
     PERF_CAPABILITIES

   - Apply PMU filters to emulated events and add test coverage to the
     pmu_event_filter selftest

   - AMD SVM:
       - Add support for virtual NMIs
       - Fixes for edge cases related to virtual interrupts

   - Intel AMX:
       - Don't advertise XTILE_CFG in KVM_GET_SUPPORTED_CPUID if
         XTILE_DATA is not being reported due to userspace not opting in
         via prctl()
       - Fix a bug in emulation of ENCLS in compatibility mode
       - Allow emulation of NOP and PAUSE for L2
       - AMX selftests improvements
       - Misc cleanups

  MIPS:

   - Constify MIPS's internal callbacks (a leftover from the hardware
     enabling rework that landed in 6.3)

  Generic:

   - Drop unnecessary casts from "void *" throughout kvm_main.c

   - Tweak the layout of "struct kvm_mmu_memory_cache" to shrink the
     struct size by 8 bytes on 64-bit kernels by utilizing a padding
     hole

  Documentation:

   - Fix goof introduced by the conversion to rST"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (211 commits)
  KVM: s390: pci: fix virtual-physical confusion on module unload/load
  KVM: s390: vsie: clarifications on setting the APCB
  KVM: s390: interrupt: fix virtual-physical confusion for next alert GISA
  KVM: arm64: Have kvm_psci_vcpu_on() use WRITE_ONCE() to update mp_state
  KVM: arm64: Acquire mp_state_lock in kvm_arch_vcpu_ioctl_vcpu_init()
  KVM: selftests: Test the PMU event "Instructions retired"
  KVM: selftests: Copy full counter values from guest in PMU event filter test
  KVM: selftests: Use error codes to signal errors in PMU event filter test
  KVM: selftests: Print detailed info in PMU event filter asserts
  KVM: selftests: Add helpers for PMC asserts in PMU event filter test
  KVM: selftests: Add a common helper for the PMU event filter guest code
  KVM: selftests: Fix spelling mistake "perrmited" -> "permitted"
  KVM: arm64: vhe: Drop extra isb() on guest exit
  KVM: arm64: vhe: Synchronise with page table walker on MMU update
  KVM: arm64: pkvm: Document the side effects of kvm_flush_dcache_to_poc()
  KVM: arm64: nvhe: Synchronise with page table walker on TLBI
  KVM: arm64: Handle 32bit CNTPCTSS traps
  KVM: arm64: nvhe: Synchronise with page table walker on vcpu run
  KVM: arm64: vgic: Don't acquire its_lock before config_lock
  KVM: selftests: Add test to verify KVM's supported XCR0
  ...
2023-05-01 12:06:20 -07:00
Alexey Kardashevskiy
52882b9c7a KVM: PPC: Make KVM_CAP_IRQFD_RESAMPLE platform dependent
When introduced, IRQFD resampling worked on POWER8 with XICS. However
KVM on POWER9 has never implemented it - the compatibility mode code
("XICS-on-XIVE") misses the kvm_notify_acked_irq() call and the native
XIVE mode does not handle INTx in KVM at all.

This moved the capability support advertising to platforms and stops
advertising it on XIVE, i.e. POWER9 and later.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Acked-by: Anup Patel <anup@brainfault.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20220504074807.3616813-1-aik@ozlabs.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-03-31 11:19:05 -04:00
Thomas Huth
d8708b80fa KVM: Change return type of kvm_arch_vm_ioctl() to "int"
All kvm_arch_vm_ioctl() implementations now only deal with "int"
types as return values, so we can change the return type of these
functions to use "int" instead of "long".

Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Anup Patel <anup@brainfault.org>
Message-Id: <20230208140105.655814-7-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-03-16 10:18:07 -04:00
Thomas Huth
71fb165e23 KVM: s390: Use "int" as return type for kvm_s390_get/set_skeys()
These two functions only return normal integers, so it does not
make sense to declare the return type as "long" here.

Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230208140105.655814-3-thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2023-03-16 10:18:06 -04:00
Paolo Bonzini
e4922088f8 Merge tag 'kvm-s390-next-6.3-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
* Two more V!=R patches
* The last part of the cmpxchg patches
* A few fixes
2023-02-15 12:35:26 -05:00
Janis Schoetterl-Glausch
3fd49805d1 KVM: s390: Extend MEM_OP ioctl by storage key checked cmpxchg
User space can use the MEM_OP ioctl to make storage key checked reads
and writes to the guest, however, it has no way of performing atomic,
key checked, accesses to the guest.
Extend the MEM_OP ioctl in order to allow for this, by adding a cmpxchg
op. For now, support this op for absolute accesses only.

This op can be used, for example, to set the device-state-change
indicator and the adapter-local-summary indicator atomically.

Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20230206164602.138068-13-scgl@linux.ibm.com
Message-Id: <20230206164602.138068-13-scgl@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-02-07 18:06:00 +01:00
Janis Schoetterl-Glausch
701422b343 KVM: s390: Refactor vcpu mem_op function
Remove code duplication with regards to the CHECK_ONLY flag.
Decrease the number of indents.
No functional change indented.

Suggested-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Link: https://lore.kernel.org/r/20230206164602.138068-12-scgl@linux.ibm.com
Message-Id: <20230206164602.138068-12-scgl@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-02-07 18:06:00 +01:00
Janis Schoetterl-Glausch
0d6d4d2395 KVM: s390: Refactor absolute vm mem_op function
Remove code duplication with regards to the CHECK_ONLY flag.
Decrease the number of indents.
No functional change indented.

Suggested-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20230206164602.138068-11-scgl@linux.ibm.com
Message-Id: <20230206164602.138068-11-scgl@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-02-07 18:05:59 +01:00
Janis Schoetterl-Glausch
8550bcb754 KVM: s390: Dispatch to implementing function at top level of vm mem_op
Instead of having one function covering all mem_op operations,
have a function implementing absolute access and dispatch to that
function in its caller, based on the operation code.
This way additional future operations can be implemented by adding an
implementing function without changing existing operations.

Suggested-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20230206164602.138068-10-scgl@linux.ibm.com
Message-Id: <20230206164602.138068-10-scgl@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-02-07 18:05:59 +01:00
Janis Schoetterl-Glausch
a41f505e9f KVM: s390: Move common code of mem_op functions into function
The vcpu and vm mem_op ioctl implementations share some functionality.
Move argument checking into a function and call it from both
implementations. This allows code reuse in case of additional future
mem_op operations.

Suggested-by: Janosch Frank <frankja@linux.ibm.com>
Signed-off-by: Janis Schoetterl-Glausch <scgl@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20230206164602.138068-9-scgl@linux.ibm.com
Message-Id: <20230206164602.138068-9-scgl@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-02-07 18:05:59 +01:00
Nico Boehr
f2d3155e2a KVM: s390: disable migration mode when dirty tracking is disabled
Migration mode is a VM attribute which enables tracking of changes in
storage attributes (PGSTE). It assumes dirty tracking is enabled on all
memslots to keep a dirty bitmap of pages with changed storage attributes.

When enabling migration mode, we currently check that dirty tracking is
enabled for all memslots. However, userspace can disable dirty tracking
without disabling migration mode.

Since migration mode is pointless with dirty tracking disabled, disable
migration mode whenever userspace disables dirty tracking on any slot.

Also update the documentation to clarify that dirty tracking must be
enabled when enabling migration mode, which is already enforced by the
code in kvm_s390_vm_start_migration().

Also highlight in the documentation for KVM_S390_GET_CMMA_BITS that it
can now fail with -EINVAL when dirty tracking is disabled while
migration mode is on. Move all the error codes to a table so this stays
readable.

To disable migration mode, slots_lock should be held, which is taken
in kvm_set_memory_region() and thus held in
kvm_arch_prepare_memory_region().

Restructure the prepare code a bit so all the sanity checking is done
before disabling migration mode. This ensures migration mode isn't
disabled when some sanity check fails.

Cc: stable@vger.kernel.org
Fixes: 190df4a212 ("KVM: s390: CMMA tracking, ESSA emulation, migration mode")
Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20230127140532.230651-2-nrb@linux.ibm.com
Message-Id: <20230127140532.230651-2-nrb@linux.ibm.com>
[frankja@linux.ibm.com: fixed commit message typo, moved api.rst error table upwards]
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2023-02-07 18:05:59 +01:00
Sean Christopherson
441f7bfa99 KVM: Opt out of generic hardware enabling on s390 and PPC
Allow architectures to opt out of the generic hardware enabling logic,
and opt out on both s390 and PPC, which don't need to manually enable
virtualization as it's always on (when available).

In addition to letting s390 and PPC drop a bit of dead code, this will
hopefully also allow ARM to clean up its related code, e.g. ARM has its
own per-CPU flag to track which CPUs have enable hardware due to the
need to keep hardware enabled indefinitely when pKVM is enabled.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Acked-by: Anup Patel <anup@brainfault.org>
Message-Id: <20221130230934.1014142-50-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:48:37 -05:00
Sean Christopherson
81a1cf9f89 KVM: Drop kvm_arch_check_processor_compat() hook
Drop kvm_arch_check_processor_compat() and its support code now that all
architecture implementations are nops.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Farman <farman@linux.ibm.com>	# s390
Acked-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Kai Huang <kai.huang@intel.com>
Message-Id: <20221130230934.1014142-33-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:41:28 -05:00
Sean Christopherson
a578a0a9e3 KVM: Drop kvm_arch_{init,exit}() hooks
Drop kvm_arch_init() and kvm_arch_exit() now that all implementations
are nops.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>	# s390
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Anup Patel <anup@brainfault.org>
Message-Id: <20221130230934.1014142-30-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:41:23 -05:00
Sean Christopherson
6c30cd2ef4 KVM: s390: Mark __kvm_s390_init() and its descendants as __init
Tag __kvm_s390_init() and its unique helpers as __init.  These functions
are only ever called during module_init(), but could not be tagged
accordingly while they were invoked from the common kvm_arch_init(),
which is not __init because of x86.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20221130230934.1014142-29-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:41:22 -05:00
Sean Christopherson
b844926591 KVM: s390: Do s390 specific init without bouncing through kvm_init()
Move the guts of kvm_arch_init() into a new helper, __kvm_s390_init(),
and invoke the new helper directly from kvm_s390_init() instead of
bouncing through kvm_init().  Invoking kvm_arch_init() is the very
first action performed by kvm_init(), i.e. this is a glorified nop.

Moving setup to __kvm_s390_init() will allow tagging more functions as
__init, and emptying kvm_arch_init() will allow dropping the hook
entirely once all architecture implementations are nops.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20221130230934.1014142-28-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:41:21 -05:00
Sean Christopherson
63a1bd8ad1 KVM: Drop arch hardware (un)setup hooks
Drop kvm_arch_hardware_setup() and kvm_arch_hardware_unsetup() now that
all implementations are nops.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>	# s390
Acked-by: Anup Patel <anup@brainfault.org>
Message-Id: <20221130230934.1014142-10-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:40:54 -05:00
Sean Christopherson
e43f576225 KVM: s390: Move hardware setup/unsetup to init/exit
Now that kvm_arch_hardware_setup() is called immediately after
kvm_arch_init(), fold the guts of kvm_arch_hardware_(un)setup() into
kvm_arch_{init,exit}() as a step towards dropping one of the hooks.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20221130230934.1014142-7-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:40:50 -05:00
Sean Christopherson
b801ef4214 KVM: s390: Unwind kvm_arch_init() piece-by-piece() if a step fails
In preparation for folding kvm_arch_hardware_setup() into kvm_arch_init(),
unwind initialization one step at a time instead of simply calling
kvm_arch_exit().  Using kvm_arch_exit() regardless of which initialization
step failed relies on all affected state playing nice with being undone
even if said state wasn't first setup.  That holds true for state that is
currently configured by kvm_arch_init(), but not for state that's handled
by kvm_arch_hardware_setup(), e.g. calling gmap_unregister_pte_notifier()
without first registering a notifier would result in list corruption due
to attempting to delete an entry that was never added to the list.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20221130230934.1014142-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-12-29 15:40:48 -05:00
Paolo Bonzini
1e79a9e3ab Merge tag 'kvm-s390-next-6.2-1' of https://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD
- Second batch of the lazy destroy patches
- First batch of KVM changes for kernel virtual != physical address support
- Removal of a unused function
2022-11-28 13:34:47 -05:00
Claudio Imbrenda
cc72688607 KVM: s390: pv: module parameter to fence asynchronous destroy
Add the module parameter "async_destroy", to allow the asynchronous
destroy mechanism to be switched off. This might be useful for
debugging purposes.

The parameter is enabled by default since the feature is opt-in anyway.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Nico Boehr <nrb@linux.ibm.com>
Link: https://lore.kernel.org/r/20221111170632.77622-7-imbrenda@linux.ibm.com
Message-Id: <20221111170632.77622-7-imbrenda@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2022-11-23 09:06:50 +00:00
Claudio Imbrenda
8c516b25d6 KVM: s390: pv: add KVM_CAP_S390_PROTECTED_ASYNC_DISABLE
Add KVM_CAP_S390_PROTECTED_ASYNC_DISABLE to signal that the
KVM_PV_ASYNC_DISABLE and KVM_PV_ASYNC_DISABLE_PREPARE commands for the
KVM_S390_PV_COMMAND ioctl are available.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20221111170632.77622-4-imbrenda@linux.ibm.com
Message-Id: <20221111170632.77622-4-imbrenda@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2022-11-23 09:06:50 +00:00
Claudio Imbrenda
fb491d5500 KVM: s390: pv: asynchronous destroy for reboot
Until now, destroying a protected guest was an entirely synchronous
operation that could potentially take a very long time, depending on
the size of the guest, due to the time needed to clean up the address
space from protected pages.

This patch implements an asynchronous destroy mechanism, that allows a
protected guest to reboot significantly faster than previously.

This is achieved by clearing the pages of the old guest in background.
In case of reboot, the new guest will be able to run in the same
address space almost immediately.

The old protected guest is then only destroyed when all of its memory
has been destroyed or otherwise made non protected.

Two new PV commands are added for the KVM_S390_PV_COMMAND ioctl:

KVM_PV_ASYNC_CLEANUP_PREPARE: set aside the current protected VM for
later asynchronous teardown. The current KVM VM will then continue
immediately as non-protected. If a protected VM had already been
set aside for asynchronous teardown, but without starting the teardown
process, this call will fail. There can be at most one VM set aside at
any time. Once it is set aside, the protected VM only exists in the
context of the Ultravisor, it is not associated with the KVM VM
anymore. Its protected CPUs have already been destroyed, but not its
memory. This command can be issued again immediately after starting
KVM_PV_ASYNC_CLEANUP_PERFORM, without having to wait for completion.

KVM_PV_ASYNC_CLEANUP_PERFORM: tears down the protected VM previously
set aside using KVM_PV_ASYNC_CLEANUP_PREPARE. Ideally the
KVM_PV_ASYNC_CLEANUP_PERFORM PV command should be issued by userspace
from a separate thread. If a fatal signal is received (or if the
process terminates naturally), the command will terminate immediately
without completing. All protected VMs whose teardown was interrupted
will be put in the need_cleanup list. The rest of the normal KVM
teardown process will take care of properly cleaning up all remaining
protected VMs, including the ones on the need_cleanup list.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Steffen Eiden <seiden@linux.ibm.com>
Link: https://lore.kernel.org/r/20221111170632.77622-2-imbrenda@linux.ibm.com
Message-Id: <20221111170632.77622-2-imbrenda@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2022-11-23 09:06:50 +00:00
Paolo Bonzini
d663b8a285 KVM: replace direct irq.h inclusion
virt/kvm/irqchip.c is including "irq.h" from the arch-specific KVM source
directory (i.e. not from arch/*/include) for the sole purpose of retrieving
irqchip_in_kernel.

Making the function inline in a header that is already included,
such as asm/kvm_host.h, is not possible because it needs to look at
struct kvm which is defined after asm/kvm_host.h is included.  So add a
kvm_arch_irqchip_in_kernel non-inline function; irqchip_in_kernel() is
only performance critical on arm64 and x86, and the non-inline function
is enough on all other architectures.

irq.h can then be deleted from all architectures except x86.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2022-11-09 12:31:37 -05:00
Nico Boehr
6973091d1b KVM: s390: pv: don't allow userspace to set the clock under PV
When running under PV, the guest's TOD clock is under control of the
ultravisor and the hypervisor isn't allowed to change it. Hence, don't
allow userspace to change the guest's TOD clock by returning
-EOPNOTSUPP.

When userspace changes the guest's TOD clock, KVM updates its
kvm.arch.epoch field and, in addition, the epoch field in all state
descriptions of all VCPUs.

But, under PV, the ultravisor will ignore the epoch field in the state
description and simply overwrite it on next SIE exit with the actual
guest epoch. This leads to KVM having an incorrect view of the guest's
TOD clock: it has updated its internal kvm.arch.epoch field, but the
ultravisor ignores the field in the state description.

Whenever a guest is now waiting for a clock comparator, KVM will
incorrectly calculate the time when the guest should wake up, possibly
causing the guest to sleep for much longer than expected.

With this change, kvm_s390_set_tod() will now take the kvm->lock to be
able to call kvm_s390_pv_is_protected(). Since kvm_s390_set_tod_clock()
also takes kvm->lock, use __kvm_s390_set_tod_clock() instead.

The function kvm_s390_set_tod_clock is now unused, hence remove it.
Update the documentation to indicate the TOD clock attr calls can now
return -EOPNOTSUPP.

Fixes: 0f30350471 ("KVM: s390: protvirt: Do only reset registers that are accessible")
Reported-by: Marc Hartmayer <mhartmay@linux.ibm.com>
Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20221011160712.928239-2-nrb@linux.ibm.com
Message-Id: <20221011160712.928239-2-nrb@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2022-11-07 10:14:15 +01:00
Nico Boehr
b99f451219 KVM: s390: sida: sort out physical vs virtual pointers usage
All callers of the sida_origin() macro actually expected a virtual
address, so rename it to sida_addr() and hand out a virtual address.

At some places, the macro wasn't used, potentially creating problems
if the sida size ever becomes nonzero (not currently the case), so let's
start using it everywhere now while at it.

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20221020143159.294605-5-nrb@linux.ibm.com
Message-Id: <20221020143159.294605-5-nrb@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2022-10-26 14:27:41 +02:00
Nico Boehr
fe0ef00304 KVM: s390: sort out physical vs virtual pointers usage
Fix virtual vs physical address confusion (which currently are the same).

Signed-off-by: Nico Boehr <nrb@linux.ibm.com>
Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20221020143159.294605-4-nrb@linux.ibm.com
Message-Id: <20221020143159.294605-4-nrb@linux.ibm.com>
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2022-10-26 14:27:41 +02:00
Linus Torvalds
ef688f8b8c Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
 "The first batch of KVM patches, mostly covering x86.

  ARM:

   - Account stage2 page table allocations in memory stats

  x86:

   - Account EPT/NPT arm64 page table allocations in memory stats

   - Tracepoint cleanups/fixes for nested VM-Enter and emulated MSR
     accesses

   - Drop eVMCS controls filtering for KVM on Hyper-V, all known
     versions of Hyper-V now support eVMCS fields associated with
     features that are enumerated to the guest

   - Use KVM's sanitized VMCS config as the basis for the values of
     nested VMX capabilities MSRs

   - A myriad event/exception fixes and cleanups. Most notably, pending
     exceptions morph into VM-Exits earlier, as soon as the exception is
     queued, instead of waiting until the next vmentry. This fixed a
     longstanding issue where the exceptions would incorrecly become
     double-faults instead of triggering a vmexit; the common case of
     page-fault vmexits had a special workaround, but now it's fixed for
     good

   - A handful of fixes for memory leaks in error paths

   - Cleanups for VMREAD trampoline and VMX's VM-Exit assembly flow

   - Never write to memory from non-sleepable kvm_vcpu_check_block()

   - Selftests refinements and cleanups

   - Misc typo cleanups

  Generic:

   - remove KVM_REQ_UNHALT"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (94 commits)
  KVM: remove KVM_REQ_UNHALT
  KVM: mips, x86: do not rely on KVM_REQ_UNHALT
  KVM: x86: never write to memory from kvm_vcpu_check_block()
  KVM: x86: Don't snapshot pending INIT/SIPI prior to checking nested events
  KVM: nVMX: Make event request on VMXOFF iff INIT/SIPI is pending
  KVM: nVMX: Make an event request if INIT or SIPI is pending on VM-Enter
  KVM: SVM: Make an event request if INIT or SIPI is pending when GIF is set
  KVM: x86: lapic does not have to process INIT if it is blocked
  KVM: x86: Rename kvm_apic_has_events() to make it INIT/SIPI specific
  KVM: x86: Rename and expose helper to detect if INIT/SIPI are allowed
  KVM: nVMX: Make an event request when pending an MTF nested VM-Exit
  KVM: x86: make vendor code check for all nested events
  mailmap: Update Oliver's email address
  KVM: x86: Allow force_emulation_prefix to be written without a reload
  KVM: selftests: Add an x86-only test to verify nested exception queueing
  KVM: selftests: Use uapi header to get VMX and SVM exit reasons/codes
  KVM: x86: Rename inject_pending_events() to kvm_check_and_inject_events()
  KVM: VMX: Update MTF and ICEBP comments to document KVM's subtle behavior
  KVM: x86: Treat pending TRIPLE_FAULT requests as pending exceptions
  KVM: x86: Morph pending exceptions to pending VM-Exits at queue time
  ...
2022-10-09 09:39:55 -07:00