Commit Graph

900458 Commits

Author SHA1 Message Date
Sean Christopherson
13e48aa942 KVM: selftests: Add test for KVM_SET_USER_MEMORY_REGION
Add a KVM selftest to test moving the base gfn of a userspace memory
region.  Although the basic concept of moving memory regions is not x86
specific, the assumptions regarding large pages and MMIO shenanigans
used to verify the correctness make this x86_64 only for the time being.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:27 +01:00
Sean Christopherson
36947254e5 KVM: Dynamically size memslot array based on number of used slots
Now that the memslot logic doesn't assume memslots are always non-NULL,
dynamically size the array of memslots instead of unconditionally
allocating memory for the maximum number of memslots.

Note, because a to-be-deleted memslot must first be invalidated, the
array size cannot be immediately reduced when deleting a memslot.
However, consecutive deletions will realize the memory savings, i.e.
a second deletion will trim the entry.

Tested-by: Christoffer Dall <christoffer.dall@arm.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:26 +01:00
Sean Christopherson
0577d1abe7 KVM: Terminate memslot walks via used_slots
Refactor memslot handling to treat the number of used slots as the de
facto size of the memslot array, e.g. return NULL from id_to_memslot()
when an invalid index is provided instead of relying on npages==0 to
detect an invalid memslot.  Rework the sorting and walking of memslots
in advance of dynamically sizing memslots to aid bisection and debug,
e.g. with luck, a bug in the refactoring will bisect here and/or hit a
WARN instead of randomly corrupting memory.

Alternatively, a global null/invalid memslot could be returned, i.e. so
callers of id_to_memslot() don't have to explicitly check for a NULL
memslot, but that approach runs the risk of introducing difficult-to-
debug issues, e.g. if the global null slot is modified.  Constifying
the return from id_to_memslot() to combat such issues is possible, but
would require a massive refactoring of arch specific code and would
still be susceptible to casting shenanigans.

Add function comments to update_memslots() and search_memslots() to
explicitly (and loudly) state how memslots are sorted.

Opportunistically stuff @hva with a non-canonical value when deleting a
private memslot on x86 to detect bogus usage of the freed slot.

No functional change intended.

Tested-by: Christoffer Dall <christoffer.dall@arm.com>
Tested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:26 +01:00
Sean Christopherson
2a49f61dfc KVM: Ensure validity of memslot with respect to kvm_get_dirty_log()
Rework kvm_get_dirty_log() so that it "returns" the associated memslot
on success.  A future patch will rework memslot handling such that
id_to_memslot() can return NULL, returning the memslot makes it more
obvious that the validity of the memslot has been verified, i.e.
precludes the need to add validity checks in the arch code that are
technically unnecessary.

To maintain ordering in s390, move the call to kvm_arch_sync_dirty_log()
from s390's kvm_vm_ioctl_get_dirty_log() to the new kvm_get_dirty_log().
This is a nop for PPC, the only other arch that doesn't select
KVM_GENERIC_DIRTYLOG_READ_PROTECT, as its sync_dirty_log() is empty.

Ideally, moving the sync_dirty_log() call would be done in a separate
patch, but it can't be done in a follow-on patch because that would
temporarily break s390's ordering.  Making the move in a preparatory
patch would be functionally correct, but would create an odd scenario
where the moved sync_dirty_log() would operate on a "different" memslot
due to consuming the result of a different id_to_memslot().  The
memslot couldn't actually be different as slots_lock is held, but the
code is confusing enough as it is, i.e. moving sync_dirty_log() in this
patch is the lesser of all evils.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:25 +01:00
Sean Christopherson
0dff084607 KVM: Provide common implementation for generic dirty log functions
Move the implementations of KVM_GET_DIRTY_LOG and KVM_CLEAR_DIRTY_LOG
for CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT into common KVM code.
The arch specific implemenations are extremely similar, differing
only in whether the dirty log needs to be sync'd from hardware (x86)
and how the TLBs are flushed.  Add new arch hooks to handle sync
and TLB flush; the sync will also be used for non-generic dirty log
support in a future patch (s390).

The ulterior motive for providing a common implementation is to
eliminate the dependency between arch and common code with respect to
the memslot referenced by the dirty log, i.e. to make it obvious in the
code that the validity of the memslot is guaranteed, as a future patch
will rework memslot handling such that id_to_memslot() can return NULL.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:24 +01:00
Sean Christopherson
163da372de KVM: Clean up local variable usage in __kvm_set_memory_region()
Clean up __kvm_set_memory_region() to achieve several goals:

  - Remove local variables that serve no real purpose
  - Improve the readability of the code
  - Better show the relationship between the 'old' and 'new' memslot
  - Prepare for dynamically sizing memslots
  - Document subtle gotchas (via comments)

Note, using 'tmp' to hold the initial memslot is not strictly necessary
at this juncture, e.g. 'old' could be directly copied from
id_to_memslot(), but keep the pointer usage as id_to_memslot() will be
able to return a NULL pointer once memslots are dynamically sized.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:23 +01:00
Sean Christopherson
e96c81ee89 KVM: Simplify kvm_free_memslot() and all its descendents
Now that all callers of kvm_free_memslot() pass NULL for @dont, remove
the param from the top-level routine and all arch's implementations.

No functional change intended.

Tested-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:22 +01:00
Sean Christopherson
5c0b4f3d5c KVM: Move memslot deletion to helper function
Move memslot deletion into its own routine so that the success path for
other memslot updates does not need to use kvm_free_memslot(), i.e. can
explicitly destroy the dirty bitmap when necessary.  This paves the way
for dropping @dont from kvm_free_memslot(), i.e. all callers now pass
NULL for @dont.

Add a comment above the code to make a copy of the existing memslot
prior to deletion, it is not at all obvious that the pointer will become
stale during sorting and/or installation of new memslots.

Note, kvm_arch_commit_memory_region() allows an architecture to free
resources when moving a memslot or changing its flags, e.g. x86 frees
its arch specific memslot metadata during commit_memory_region().

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Tested-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:22 +01:00
Sean Christopherson
21198846de KVM: x86: Free arrays for old memslot when moving memslot's base gfn
Explicitly free the metadata arrays (stored in slot->arch) in the old
memslot structure when moving the memslot's base gfn is committed.  This
eliminates x86's dependency on kvm_free_memslot() being called when a
memslot move is committed, and paves the way for removing the funky code
in kvm_free_memslot() that conditionally frees structures based on its
@dont param.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:21 +01:00
Sean Christopherson
9d4c197c0e KVM: Drop "const" attribute from old memslot in commit_memory_region()
Drop the "const" attribute from @old in kvm_arch_commit_memory_region()
to allow arch specific code to free arch specific resources in the old
memslot without having to cast away the attribute.  Freeing resources in
kvm_arch_commit_memory_region() paves the way for simplifying
kvm_free_memslot() by eliminating the last usage of its @dont param.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:20 +01:00
Sean Christopherson
cf47f50b5c KVM: Move setting of memslot into helper routine
Split out the core functionality of setting a memslot into a separate
helper in preparation for moving memslot deletion into its own routine.

Tested-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:19 +01:00
Sean Christopherson
71a4c30bf0 KVM: Refactor error handling for setting memory region
Replace a big pile o' gotos with returns to make it more obvious what
error code is being returned, and to prepare for refactoring the
functional, i.e. post-checks, portion of __kvm_set_memory_region().

Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:19 +01:00
Sean Christopherson
bd0e96fdc5 KVM: Explicitly free allocated-but-unused dirty bitmap
Explicitly free an allocated-but-unused dirty bitmap instead of relying
on kvm_free_memslot() if an error occurs in __kvm_set_memory_region().
There is no longer a need to abuse kvm_free_memslot() to free arch
specific resources as arch specific code is now called only after the
common flow is guaranteed to succeed.  Arch code can still fail, but
it's responsible for its own cleanup in that case.

Eliminating the error path's abuse of kvm_free_memslot() paves the way
for simplifying kvm_free_memslot(), i.e. dropping its @dont param.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:18 +01:00
Sean Christopherson
414de7abbf KVM: Drop kvm_arch_create_memslot()
Remove kvm_arch_create_memslot() now that all arch implementations are
effectively nops.  Removing kvm_arch_create_memslot() eliminates the
possibility for arch specific code to allocate memory prior to setting
a memslot, which sets the stage for simplifying kvm_free_memslot().

Cc: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:17 +01:00
Sean Christopherson
0dab98b7ad KVM: x86: Allocate memslot resources during prepare_memory_region()
Allocate the various metadata structures associated with a new memslot
during kvm_arch_prepare_memory_region(), which paves the way for
removing kvm_arch_create_memslot() altogether.  Moving x86's memory
allocation only changes the order of kernel memory allocations between
x86 and common KVM code.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:16 +01:00
Sean Christopherson
82307e676f KVM: PPC: Move memslot memory allocation into prepare_memory_region()
Allocate the rmap array during kvm_arch_prepare_memory_region() to pave
the way for removing kvm_arch_create_memslot() altogether.  Moving PPC's
memory allocation only changes the order of kernel memory allocations
between PPC and common KVM code.

No functional change intended.

Acked-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:15 +01:00
Sean Christopherson
13f678894b KVM: Don't free new memslot if allocation of said memslot fails
The two implementations of kvm_arch_create_memslot() in x86 and PPC are
both good citizens and free up all local resources if creation fails.
Return immediately (via a superfluous goto) instead of calling
kvm_free_memslot().

Note, the call to kvm_free_memslot() is effectively an expensive nop in
this case as there are no resources to be freed.

No functional change intended.

Acked-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:15 +01:00
Sean Christopherson
13ea525517 KVM: Reinstall old memslots if arch preparation fails
Reinstall the old memslots if preparing the new memory region fails
after invalidating a to-be-{re}moved memslot.

Remove the superfluous 'old_memslots' variable so that it's somewhat
clear that the error handling path needs to free the unused memslots,
not simply the 'old' memslots.

Fixes: bc6678a33d ("KVM: introduce kvm->srcu and convert kvm_set_memory_region to SRCU update")
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:14 +01:00
Sean Christopherson
edd4fa37ba KVM: x86: Allocate new rmap and large page tracking when moving memslot
Reallocate a rmap array and recalcuate large page compatibility when
moving an existing memslot to correctly handle the alignment properties
of the new memslot.  The number of rmap entries required at each level
is dependent on the alignment of the memslot's base gfn with respect to
that level, e.g. moving a large-page aligned memslot so that it becomes
unaligned will increase the number of rmap entries needed at the now
unaligned level.

Not updating the rmap array is the most obvious bug, as KVM accesses
garbage data beyond the end of the rmap.  KVM interprets the bad data as
pointers, leading to non-canonical #GPs, unexpected #PFs, etc...

  general protection fault: 0000 [#1] SMP
  CPU: 0 PID: 1909 Comm: move_memory_reg Not tainted 5.4.0-rc7+ #139
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  RIP: 0010:rmap_get_first+0x37/0x50 [kvm]
  Code: <48> 8b 3b 48 85 ff 74 ec e8 6c f4 ff ff 85 c0 74 e3 48 89 d8 5b c3
  RSP: 0018:ffffc9000021bbc8 EFLAGS: 00010246
  RAX: ffff00617461642e RBX: ffff00617461642e RCX: 0000000000000012
  RDX: ffff88827400f568 RSI: ffffc9000021bbe0 RDI: ffff88827400f570
  RBP: 0010000000000000 R08: ffffc9000021bd00 R09: ffffc9000021bda8
  R10: ffffc9000021bc48 R11: 0000000000000000 R12: 0030000000000000
  R13: 0000000000000000 R14: ffff88827427d700 R15: ffffc9000021bce8
  FS:  00007f7eda014700(0000) GS:ffff888277a00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f7ed9216ff8 CR3: 0000000274391003 CR4: 0000000000162eb0
  Call Trace:
   kvm_mmu_slot_set_dirty+0xa1/0x150 [kvm]
   __kvm_set_memory_region.part.64+0x559/0x960 [kvm]
   kvm_set_memory_region+0x45/0x60 [kvm]
   kvm_vm_ioctl+0x30f/0x920 [kvm]
   do_vfs_ioctl+0xa1/0x620
   ksys_ioctl+0x66/0x70
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x4c/0x170
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f7ed9911f47
  Code: <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 21 6f 2c 00 f7 d8 64 89 01 48
  RSP: 002b:00007ffc00937498 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 0000000001ab0010 RCX: 00007f7ed9911f47
  RDX: 0000000001ab1350 RSI: 000000004020ae46 RDI: 0000000000000004
  RBP: 000000000000000a R08: 0000000000000000 R09: 00007f7ed9214700
  R10: 00007f7ed92149d0 R11: 0000000000000246 R12: 00000000bffff000
  R13: 0000000000000003 R14: 00007f7ed9215000 R15: 0000000000000000
  Modules linked in: kvm_intel kvm irqbypass
  ---[ end trace 0c5f570b3358ca89 ]---

The disallow_lpage tracking is more subtle.  Failure to update results
in KVM creating large pages when it shouldn't, either due to stale data
or again due to indexing beyond the end of the metadata arrays, which
can lead to memory corruption and/or leaking data to guest/userspace.

Note, the arrays for the old memslot are freed by the unconditional call
to kvm_free_memslot() in __kvm_set_memory_region().

Fixes: 05da45583d ("KVM: MMU: large page support")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:13 +01:00
Sean Christopherson
744e699c7e KVM: x86: Move gpa_val and gpa_available into the emulator context
Move the GPA tracking into the emulator context now that the context is
guaranteed to be initialized via __init_emulate_ctxt() prior to
dereferencing gpa_{available,val}, i.e. now that seeing a stale
gpa_available will also trigger a WARN due to an invalid context.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:12 +01:00
Sean Christopherson
92daa48b34 KVM: x86: Add EMULTYPE_PF when emulation is triggered by a page fault
Add a new emulation type flag to explicitly mark emulation related to a
page fault.  Move the propation of the GPA into the emulator from the
page fault handler into x86_emulate_instruction, using EMULTYPE_PF as an
indicator that cr2 is valid.  Similarly, don't propagate cr2 into the
exception.address when it's *not* valid.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:12 +01:00
Miaohe Lin
999eabcc89 KVM: apic: remove unused function apic_lvt_vector()
The function apic_lvt_vector() is unused now, remove it.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:11 +01:00
Miaohe Lin
d71f5e0325 KVM: VMX: Add 'else' to split mutually exclusive case
Each if branch in handle_external_interrupt_irqoff() is mutually
exclusive. Add 'else' to make it clear and also avoid some unnecessary
check.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:10 +01:00
Miaohe Lin
e080e538e6 KVM: x86: eliminate some unreachable code
These code are unreachable, remove them.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:09 +01:00
Miaohe Lin
e630269841 KVM: x86: Fix print format and coding style
Use %u to print u32 var and correct some coding style.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:08 +01:00
Chia-I Wu
222f06e7cd KVM: vmx: rewrite the comment in vmx_get_mt_mask
Better reflect the structure of the code and metion why we could not
always honor the guest.

Signed-off-by: Chia-I Wu <olvaffe@gmail.com>
Cc: Gurchetan Singh <gurchetansingh@chromium.org>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:08 +01:00
Andrew Jones
244c6b6df9 KVM: selftests: Convert some printf's to pr_info's
We leave some printf's because they inform the user the test is being
skipped. QUIET should not disable those. We also leave the printf's
used for help text.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:07 +01:00
Andrew Jones
3439d886e4 KVM: selftests: Rework debug message printing
There were a few problems with the way we output "debug" messages.
The first is that we used DEBUG() which is defined when NDEBUG is
not defined, but NDEBUG will never be defined for kselftests
because it relies too much on assert(). The next is that most
of the DEBUG() messages were actually "info" messages, which
users may want to turn off if they just want a silent test that
either completes or asserts. Finally, a debug message output from
a library function, and thus for all tests, was annoying when its
information wasn't interesting for a test.

Rework these messages so debug messages only output when DEBUG
is defined and info messages output unless QUIET is defined.
Also name the functions pr_debug and pr_info and make sure that
when they're disabled we eat all the inputs. The later avoids
unused variable warnings when the variables were only defined
for the purpose of printing.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:06 +01:00
Ben Gardon
f09205b998 KVM: selftests: Time guest demand paging
In order to quantify demand paging performance, time guest execution
during demand paging.

Signed-off-by: Ben Gardon <bgardon@google.com>
[Move timespec-diff to test_util.h]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:05 +01:00
Ben Gardon
018494e6d8 KVM: selftests: Support multiple vCPUs in demand paging test
Most VMs have multiple vCPUs, the concurrent execution of which has a
substantial impact on demand paging performance. Add an option to create
multiple vCPUs to each access disjoint regions of memory.

Signed-off-by: Ben Gardon <bgardon@google.com>
[guest_code() can't return, use GUEST_ASSERT(). Ensure the number
 of guests pages is compatible with the host.]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:05 +01:00
Ben Gardon
9bbf24744e KVM: selftests: Add support for vcpu_args_set to aarch64 and s390x
Currently vcpu_args_set is only implemented for x86. This makes writing
tests with multiple vCPUs difficult as each guest vCPU must either a.)
do the same thing or b.) derive some kind of unique token from it's
registers or the architecture. To simplify the process of writing tests
with multiple vCPUs for s390 and aarch64, add set args functions for
those architectures.

Signed-off-by: Ben Gardon <bgardon@google.com>
[Fixed array index (num => i) and made some style changes.]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:04 +01:00
Ben Gardon
56a4210f4e KVM: selftests: Pass args to vCPU in global vCPU args struct
In preparation for supporting multiple vCPUs in the demand paging test,
pass arguments to the vCPU in a consolidated global struct instead of
syncing multiple globals.

Signed-off-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:03 +01:00
Ben Gardon
af99e1ad7e KVM: selftests: Add memory size parameter to the demand paging test
Add an argument to allow the demand paging test to work on larger and
smaller guest sizes.

Signed-off-by: Ben Gardon <bgardon@google.com>
[Rewrote parse_size() to simplify and provide user more flexibility as
 to how sizes are input. Also fixed size overflow assert.]
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:57:02 +01:00
Ben Gardon
0119cb365c KVM: selftests: Add configurable demand paging delay
When running the demand paging test with the -u option, the User Fault
FD handler essentially adds an arbitrary delay to page fault resolution.
To enable better simulation of a real demand paging scenario, add a
configurable delay to the UFFD handler.

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:56:58 +01:00
Ben Gardon
4f72180eb4 KVM: selftests: Add demand paging content to the demand paging test
The demand paging test is currently a simple page access test which, while
potentially useful, doesn't add much versus the existing dirty logging
test. To improve the demand paging test, add a basic userfaultfd demand
paging implementation.

Signed-off-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-16 17:56:48 +01:00
Ben Gardon
025eed7b35 KVM: selftests: Create a demand paging test
While userfaultfd, KVM's demand paging implementation, is not specific
to KVM, having a benchmark for its performance will be useful for
guiding performance improvements to KVM. As a first step towards creating
a userfaultfd demand paging test, create a simple memory access test,
based on dirty_log_test.

Reviewed-by: Oliver Upton <oupton@google.com>
Signed-off-by: Ben Gardon <bgardon@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 20:05:24 +01:00
Andrew Jones
87a802d93e KVM: selftests: Introduce num-pages conversion utilities
Guests and hosts don't have to have the same page size. This means
calculations are necessary when selecting the number of guest pages
to allocate in order to ensure the number is compatible with the
host. Provide utilities to help with those calculations and apply
them where appropriate.

We also revert commit bffed38d4f ("kvm: selftests: aarch64:
dirty_log_test: fix unaligned memslot size") and then use
vm_adjust_num_guest_pages() there instead.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 20:05:23 +01:00
Andrew Jones
377a41c9ef KVM: selftests: Introduce vm_guest_mode_params
This array will allow us to easily translate modes to their parameter
values.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 20:05:22 +01:00
Andrew Jones
f832485df2 KVM: selftests: Rename vm_guest_mode_params
We're going to want this name in the library code, so use a shorter
name in the tests.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 20:05:22 +01:00
Andrew Jones
12c0d0f6d9 KVM: selftests: aarch64: Remove unnecessary ifdefs
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 20:05:21 +01:00
Andrew Jones
10d1a71b16 KVM: selftests: Remove unnecessary defines
BITS_PER_LONG and friends are provided by linux/bitops.h

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 20:05:20 +01:00
Andrew Jones
f09ab268bb KVM: selftests: aarch64: Use stream when given
I'm not sure how we ended up using printf instead of fprintf in
virt_dump(). Fix it.

Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 20:05:19 +01:00
Christian Borntraeger
a93236fcbe KVM: s390: rstify new ioctls in api.rst
We also need to rstify the new ioctls that we added in parallel to the
rstification of the kvm docs.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-24 19:28:40 +01:00
Oliver Upton
35a571346a KVM: nVMX: Check IO instruction VM-exit conditions
Consult the 'unconditional IO exiting' and 'use IO bitmaps' VM-execution
controls when checking instruction interception. If the 'use IO bitmaps'
VM-execution control is 1, check the instruction access against the IO
bitmaps to determine if the instruction causes a VM-exit.

Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-23 10:16:32 +01:00
Oliver Upton
e71237d3ff KVM: nVMX: Refactor IO bitmap checks into helper function
Checks against the IO bitmap are useful for both instruction emulation
and VM-exit reflection. Refactor the IO bitmap checks into a helper
function.

Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-23 10:14:40 +01:00
Paolo Bonzini
07721feee4 KVM: nVMX: Don't emulate instructions in guest mode
vmx_check_intercept is not yet fully implemented. To avoid emulating
instructions disallowed by the L1 hypervisor, refuse to emulate
instructions by default.

Cc: stable@vger.kernel.org
[Made commit, added commit msg - Oliver]
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-23 10:11:55 +01:00
Oliver Upton
5ef8acbdd6 KVM: nVMX: Emulate MTF when performing instruction emulation
Since commit 5f3d45e7f2 ("kvm/x86: add support for
MONITOR_TRAP_FLAG"), KVM has allowed an L1 guest to use the monitor trap
flag processor-based execution control for its L2 guest. KVM simply
forwards any MTF VM-exits to the L1 guest, which works for normal
instruction execution.

However, when KVM needs to emulate an instruction on the behalf of an L2
guest, the monitor trap flag is not emulated. Add the necessary logic to
kvm_skip_emulated_instruction() to synthesize an MTF VM-exit to L1 upon
instruction emulation for L2.

Fixes: 5f3d45e7f2 ("kvm/x86: add support for MONITOR_TRAP_FLAG")
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-23 09:36:23 +01:00
Li RongQing
dd58f3c95c KVM: fix error handling in svm_hardware_setup
rename svm_hardware_unsetup as svm_hardware_teardown, move
it before svm_hardware_setup, and call it to free all memory
if fail to setup in svm_hardware_setup, otherwise memory will
be leaked

remove __exit attribute for it since it is called in __init
function

Signed-off-by: Li RongQing <lirongqing@baidu.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-23 09:34:26 +01:00
Miaohe Lin
d80b64ff29 KVM: SVM: Fix potential memory leak in svm_cpu_init()
When kmalloc memory for sd->sev_vmcbs failed, we forget to free the page
held by sd->save_area. Also get rid of the var r as '-ENOMEM' is actually
the only possible outcome here.

Reviewed-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:06:04 +01:00
Miaohe Lin
23520b2def KVM: apic: avoid calculating pending eoi from an uninitialized val
When pv_eoi_get_user() fails, 'val' may remain uninitialized and the return
value of pv_eoi_get_pending() becomes random. Fix the issue by initializing
the variable.

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:05:44 +01:00