Commit e45adf66 ("KVM: Introduce a new guest mapping API", 2019-01-31)
introduced a build failure on aarch64 defconfig:

$ make -j$(nproc) ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- O=out defconfig \
                Image.gz
...
../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:
    In function '__kvm_map_gfn':
../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:1763:9: error:
    implicit declaration of function 'memremap'; did you mean 'memset_p'?
../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:1763:46: error:
    'MEMREMAP_WB' undeclared (first use in this function)
../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:
    In function 'kvm_vcpu_unmap':
../arch/arm64/kvm/../../../virt/kvm/kvm_main.c:1795:3: error:
    implicit declaration of function 'memunmap'; did you mean 'vm_munmap'?

because these functions are declared in <linux/io.h> rather than <asm/io.h>,
and the former was being pulled in already on x86 but not on aarch64.
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Merge tag 'kvmarm-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for 5.2

- guest SVE support
- guest Pointer Authentication support
- Better discrimination of perf counters between host and guests

Conflicts:
	include/uapi/linux/kvm.h

Merge tag 'kvm-ppc-next-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

PPC KVM update for 5.2

* Support for guests to access the new POWER9 XIVE interrupt controller
  hardware directly, reducing interrupt latency and overhead for guests.

* In-kernel implementation of the H_PAGE_INIT hypercall.

* Reduce memory usage of sparsely-populated IOMMU tables.

* Several bug fixes.

Second PPC KVM update for 5.2

* Fix a bug, fix a spelling mistake, remove some useless code.

The RDPMC-exiting control is dependent on the existence of the RDPMC
instruction itself, i.e. is not tied to the "Architectural Performance
Monitoring" feature.  For all intents and purposes, the control exists
on all CPUs with VMX support since RDPMC also exists on all VCPUs with
VMX supported.  Per Intel's SDM:

  The RDPMC instruction was introduced into the IA-32 Architecture in
  the Pentium Pro processor and the Pentium processor with MMX technology.
  The earlier Pentium processors have performance-monitoring counters, but
  they must be read with the RDMSR instruction.

Because RDPMC-exiting always exists, KVM requires the control and refuses
to load if it's not available.  As a result, hiding the PMU from a guest
breaks nested virtualization if the guest attemts to use KVM.

While it's not explicitly stated in the RDPMC pseudocode, the VM-Exit
check for RDPMC-exiting follows standard fault vs. VM-Exit prioritization
for privileged instructions, e.g. occurs after the CPL/CR0.PE/CR4.PCE
checks, but before the counter referenced in ECX is checked for validity.

In other words, the original KVM behavior of injecting a #GP was correct,
and the KVM unit test needs to be adjusted accordingly, e.g. eat the #GP
when the unit test guest (L3 in this case) executes RDPMC without
RDPMC-exiting set in the unit test host (L2).

This reverts commit e51bfdb6.

Fixes: e51bfdb6 ("KVM: nVMX: Expose RDPMC-exiting only when guest supports PMU")
Reported-by: David Hill <hilld@binarystorm.net>
Cc: Saar Amar <saaramar@microsoft.com>
Cc: Mihai Carabas <mihai.carabas@oracle.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Liran Alon <liran.alon@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Currently KVM sets 5 most significant bits of physical address bits
reported by CPUID (boot_cpu_data.x86_phys_bits) for nonpresent or
reserved bits SPTE to mitigate L1TF attack from guest when using shadow
MMU. However for some particular Intel CPUs the physical address bits
of internal cache is greater than physical address bits reported by
CPUID.

Use the kernel's existing boot_cpu_data.x86_cache_bits to determine the
five most significant bits. Doing so improves KVM's L1TF mitigation in
the unlikely scenario that system RAM overlaps the high order bits of
the "real" physical address space as reported by CPUID. This aligns with
the kernel's warnings regarding L1TF mitigation, e.g. in the above
scenario the kernel won't warn the user about lack of L1TF mitigation
if x86_cache_bits is greater than x86_phys_bits.

Also initialize shadow_nonpresent_or_rsvd_mask explicitly to make it
consistent with other 'shadow_{xxx}_mask', and opportunistically add a
WARN once if KVM's L1TF mitigation cannot be applied on a system that
is marked as being susceptible to L1TF.
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Kai Huang <kai.huang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

If L1 is using an MSR bitmap, unconditionally merge the MSR bitmaps from
L0 and L1 for MSR_{KERNEL,}_{FS,GS}_BASE.  KVM unconditionally exposes
MSRs L1.  If KVM is also running in L1 then it's highly likely L1 is
also exposing the MSRs to L2, i.e. KVM doesn't need to intercept L2
accesses.

Based on code from Jintack Lim.

Cc: Jintack Lim <jintack@xxxxxxxxxxxxxxx>
Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

There is no need to test for the device pointer validity when releasing
a KVM device. The file descriptor should identify it safely.

Fixes: 2bde9b3e ("KVM: Introduce a 'release' method for KVM devices")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

There is a spelling mistake in a pr_err message, fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

Commit 70ea13f6 ("KVM: PPC: Book3S HV: Flush TLB on secondary radix
threads", 2019-04-29) aimed to make radix guests that are using the
real-mode entry path load the LPID register and flush the TLB in the
same place where those things are done for HPT guests.  However, it
omitted to remove a branch which branches around that code for radix
guests.  The result is that with indep_thread_mode = N, radix guests
don't run correctly.  (With indep_threads_mode = Y, which is the
default, radix guests use a different entry path.)

This removes the offending branch, and also the load and compare that
the branch depends on, since the cr7 setting is now unused.
Reported-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Tested-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Fixes: 70ea13f6 ("KVM: PPC: Book3S HV: Flush TLB on secondary radix threads")
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

nested_run_pending=1 implies we have successfully entered guest mode.
Move setting from external state in vmx_set_nested_state() until after
all other checks are complete.

Based on a patch by Aaron Lewis.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Add tests for KVM_SET_NESTED_STATE and for various code paths in its implementation in vmx_set_nested_state().
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Move call to nested_enable_evmcs until after free_nested() is complete.
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Marc Orr <marcorr@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The previous KVM_CAP_MANUAL_DIRTY_LOG_PROTECT has some problem which
blocks the correct usage from userspace.  Obsolete the old one and
introduce a new capability bit for it.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Just imaging the case where num_pages < BITS_PER_LONG, then the loop
will be skipped while it shouldn't.
Signed-off-by: Peter Xu <peterx@redhat.com>
Fixes: 2a31b9dbSigned-off-by: Paolo Bonzini <pbonzini@redhat.com>

kvm_dirty_bitmap_bytes() will return the size of the dirty bitmap of
the memslot rather than the size of bitmap passed over from the ioctl.
Here for KVM_CLEAR_DIRTY_LOG we should only copy exactly the size of
bitmap that covers kvm_clear_dirty_log.num_pages.
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 2a31b9dbSigned-off-by: Paolo Bonzini <pbonzini@redhat.com>

When a VCPU doesn't have pointer auth, we want to hide all four pointer
auth ID register fields from the guest, not just one of them.

Fixes: 384b40ca ("KVM: arm/arm64: Context-switch ptrauth registers")
Reported-by: Andrew Murray <andrew.murray@arm.com>
Fscked-up-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

Use specific inline functions for RIP and RSP instead of
going through kvm_register_read and kvm_register_write,
which are quite a mouthful.  kvm_rsp_read and kvm_rsp_write
did not exist, so add them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

... now that there is no overhead when using dedicated accessors.

Opportunistically remove a bogus "FIXME" in handle_rdmsr() regarding
the upper 32 bits of RAX and RDX.  Zeroing the upper 32 bits is
architecturally correct as 32-bit writes in 64-bit mode unconditionally
clear the upper 32 bits.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Except for RSP and RIP, which are held in VMX's VMCS, GPRs are always
treated "available and dirtly" on both VMX and SVM, i.e. are
unconditionally loaded/saved immediately before/after VM-Enter/VM-Exit.

Eliminating the unnecessary caching code reduces the size of KVM by a
non-trivial amount, much of which comes from the most common code paths.
E.g. on x86_64, kvm_emulate_cpuid() is reduced from 342 to 182 bytes and
kvm_emulate_hypercall() from 1362 to 1143, with the total size of KVM
dropping by ~1000 bytes.  With CONFIG_RETPOLINE=y, the numbers are even
more pronounced, e.g.: 353->182, 1418->1172 and well over 2000 bytes.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

pfn_valid check is not sufficient because it only checks if a page has a struct
page or not, if "mem=" was passed to the kernel some valid pages won't have a
struct page. This means that if guests were assigned valid memory that lies
after the mem= boundary it will be passed uncached to the guest no matter what
the guest caching attributes are for this memory.

Introduce a new function e820__mapped_raw_any which is equivalent to
e820__mapped_any but uses the original e820 unmodified and use it to
identify real *RAM*.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use page_address_valid in a few more locations that is already checking for
a page aligned address that does not cross the maximum physical address.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_vcpu_map for accessing the enlightened VMCS since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_vcpu_map for accessing the shadow VMCS since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzessutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use the new mapping API for mapping guest memory to avoid depending on
"struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_vcpu_map in emulator_cmpxchg_emulated since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <kjonrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_vcpu_map when mapping the posted interrupt descriptor table since
using kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory
that has a "struct page".

One additional semantic change is that the virtual host mapping lifecycle
has changed a bit. It now has the same lifetime of the pinning of the
interrupt descriptor table page on the host side.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_vcpu_map when mapping the virtual APIC page since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".

One additional semantic change is that the virtual host mapping lifecycle
has changed a bit. It now has the same lifetime of the pinning of the
virtual APIC page on the host side.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_vcpu_map when mapping the L1 MSR bitmap since using
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Use kvm_vcpu_map to the map the VMCS12 from guest memory because
kvm_vcpu_gpa_to_page() and kmap() will only work for guest memory that has
a "struct page".
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In KVM, specially for nested guests, there is a dominant pattern of:

	=> map guest memory -> do_something -> unmap guest memory

In addition to all this unnecessarily noise in the code due to boiler plate
code, most of the time the mapping function does not properly handle memory
that is not backed by "struct page". This new guest mapping API encapsulate
most of this boiler plate code and also handles guest memory that is not
backed by "struct page".

The current implementation of this API is using memremap for memory that is
not backed by a "struct page" which would lead to a huge slow-down if it
was used for high-frequency mapping operations. The API does not have any
effect on current setups where guest memory is backed by a "struct page".
Further patches are going to also introduce a pfn-cache which would
significantly improve the performance of the memremap case.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

cmpxchg_gpte() calls get_user_pages_fast() to retrieve the number of
pages and the respective struct page to map in the kernel virtual
address space.
This doesn't work if get_user_pages_fast() is invoked with a userspace
virtual address that's backed by PFNs outside of kernel reach (e.g., when
limiting the kernel memory with mem= in the command line and using
/dev/mem to map memory).

If get_user_pages_fast() fails, look up the VMA that back the userspace
virtual address, compute the PFN and the physical address, and map it in
the kernel virtual address space with memremap().
Signed-off-by: Filippo Sironi <sironi@amazon.de>
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Update the PML table without mapping and unmapping the page. This also
avoids using kvm_vcpu_gpa_to_page(..) which assumes that there is a "struct
page" for guest memory.

As a side-effect of using kvm_write_guest_page the page is also properly
marked as dirty.
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Read the data directly from guest memory instead of the map->read->unmap
sequence. This also avoids using kvm_vcpu_gpa_to_page() and kmap() which
assumes that there is a "struct page" for guest memory.
Suggested-by: Jim Mattson <jmattson@google.com>
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The hardware configuration register has some useful bits which can be
used by guests. Implement McStatusWrEn which can be used by guests when
injecting MCEs with the in-kernel mce-inject module.

For that, we need to set bit 18 - McStatusWrEn - first, before writing
the MCi_STATUS registers (otherwise we #GP).

Add the required machinery to do so.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: KVM <kvm@vger.kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yazen Ghannam <Yazen.Ghannam@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The capabilities header depends on asm/vmx.h but doesn't explicitly
include said file.  This currently doesn't cause problems as all users
of capbilities.h first include asm/vmx.h, but the issue often results in
build errors if someone starts moving things around the VMX files.

Fixes: 3077c191 ("KVM: VMX: Move capabilities structs and helpers to dedicated file")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Smatch complains about this:

    arch/x86/kvm/vmx/vmx.c:5730 dump_vmcs()
    warn: KERN_* level not at start of string

The code should be using pr_cont() instead of pr_err().

Fixes: 9d609649 ("KVM: vmx: print more APICv fields in dump_vmcs")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

is_dirty has been renamed to flush, but the comment for it is
outdated. And the description about @flush parameter for
kvm_clear_dirty_log_protect() is missing, add it in this patch
as well.
Signed-off-by: Jiang Biao <benbjiang@tencent.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

If a memory slot's size is not a multiple of 64 pages (256K), then
the KVM_CLEAR_DIRTY_LOG API is unusable: clearing the final 64 pages
either requires the requested page range to go beyond memslot->npages,
or requires log->num_pages to be unaligned, and kvm_clear_dirty_log_protect
requires log->num_pages to be both in range and aligned.

To allow this case, allow log->num_pages not to be a multiple of 64 if
it ends exactly on the last page of the slot.
Reported-by: Peter Xu <peterx@redhat.com>
Fixes: 98938aa8 ("KVM: validate userspace input in kvm_clear_dirty_log_protect()", 2019-01-02)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>