Commit Graph

900433 Commits

Author SHA1 Message Date
Haiwei Li
aaca21007b KVM: SVM: Fix the svm vmexit code for WRMSR
In svm, exit_code for MSR writes is not EXIT_REASON_MSR_WRITE which
belongs to vmx.

According to amd manual, SVM_EXIT_MSR(7ch) is the exit_code of VMEXIT_MSR
due to RDMSR or WRMSR access to protected MSR. Additionally, the processor
indicates in the VMCB's EXITINFO1 whether a RDMSR(EXITINFO1=0) or
WRMSR(EXITINFO1=1) was intercepted.

Signed-off-by: Haiwei Li <lihaiwei@tencent.com>
Fixes: 1e9e2622a1 ("KVM: VMX: FIXED+PHYSICAL mode single target IPI fastpath", 2019-11-21)
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-02 17:06:52 +01:00
Wanpeng Li
9a11997e75 KVM: X86: Fix dereference null cpufreq policy
Naresh Kamboju reported:

   Linux version 5.6.0-rc4 (oe-user@oe-host) (gcc version
  (GCC)) #1 SMP Sun Mar 1 22:59:08 UTC 2020
   kvm: no hardware support
   BUG: kernel NULL pointer dereference, address: 000000000000028c
   #PF: supervisor read access in kernel mode
   #PF: error_code(0x0000) - not-present page
   PGD 0 P4D 0
   Oops: 0000 [#1] SMP NOPTI
   CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4 #1
   Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
  04/01/2014
   RIP: 0010:kobject_put+0x12/0x1c0
   Call Trace:
    cpufreq_cpu_put+0x15/0x20
    kvm_arch_init+0x1f6/0x2b0
    kvm_init+0x31/0x290
    ? svm_check_processor_compat+0xd/0xd
    ? svm_check_processor_compat+0xd/0xd
    svm_init+0x21/0x23
    do_one_initcall+0x61/0x2f0
    ? rdinit_setup+0x30/0x30
    ? rcu_read_lock_sched_held+0x4f/0x80
    kernel_init_freeable+0x219/0x279
    ? rest_init+0x250/0x250
    kernel_init+0xe/0x110
    ret_from_fork+0x27/0x50
   Modules linked in:
   CR2: 000000000000028c
   ---[ end trace 239abf40c55c409b ]---
   RIP: 0010:kobject_put+0x12/0x1c0

cpufreq policy which is get by cpufreq_cpu_get() can be NULL if it is failure,
this patch takes care of it.

Fixes: aaec7c03de (KVM: x86: avoid useless copy of cpufreq policy)
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Cc: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-02 17:06:52 +01:00
Oliver Upton
86f7e90ce8 KVM: VMX: check descriptor table exits on instruction emulation
KVM emulates UMIP on hardware that doesn't support it by setting the
'descriptor table exiting' VM-execution control and performing
instruction emulation. When running nested, this emulation is broken as
KVM refuses to emulate L2 instructions by default.

Correct this regression by allowing the emulation of descriptor table
instructions if L1 hasn't requested 'descriptor table exiting'.

Fixes: 07721feee4 ("KVM: nVMX: Don't emulate instructions in guest mode")
Reported-by: Jan Kiszka <jan.kiszka@web.de>
Cc: stable@vger.kernel.org
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Jim Mattson <jmattson@google.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-03-01 19:26:31 +01:00
Paolo Bonzini
e951445f4d KVM/arm fixes for 5.6, take #1
- Fix compilation on 32bit
 - Move  VHE guest entry/exit into the VHE-specific entry code
 - Make sure all functions called by the non-VHE HYP code is tagged as __always_inline
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Merge tag 'kvmarm-fixes-5.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm fixes for 5.6, take #1

- Fix compilation on 32bit
- Move  VHE guest entry/exit into the VHE-specific entry code
- Make sure all functions called by the non-VHE HYP code is tagged as __always_inline
2020-02-28 11:50:06 +01:00
Erwan Velu
ef935c25fd kvm: x86: Limit the number of "kvm: disabled by bios" messages
In older version of systemd(219), at boot time, udevadm is called with :
	/usr/bin/udevadm trigger --type=devices --action=add"

This program generates an echo "add" in /sys/devices/system/cpu/cpu<x>/uevent,
leading to the "kvm: disabled by bios" message in case of your Bios disabled
the virtualization extensions.

On a modern system running up to 256 CPU threads, this pollutes the Kernel logs.

This patch offers to ratelimit this message to avoid any userspace program triggering
this uevent printing this message too often.

This patch is only a workaround but greatly reduce the pollution without
breaking the current behavior of printing a message if some try to instantiate
KVM on a system that doesn't support it.

Note that recent versions of systemd (>239) do not have trigger this behavior.

This patch will be useful at least for some using older systemd with recent Kernels.

Signed-off-by: Erwan Velu <e.velu@criteo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 11:37:20 +01:00
Paolo Bonzini
aaec7c03de KVM: x86: avoid useless copy of cpufreq policy
struct cpufreq_policy is quite big and it is not a good idea
to allocate one on the stack.  Just use cpufreq_cpu_get and
cpufreq_cpu_put which is even simpler.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:54:50 +01:00
Paolo Bonzini
4f337faf1c KVM: allow disabling -Werror
Restrict -Werror to well-tested configurations and allow disabling it
via Kconfig.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:45:28 +01:00
Valdis Klētnieks
575b255c16 KVM: x86: allow compiling as non-module with W=1
Compile error with CONFIG_KVM_INTEL=y and W=1:

  CC      arch/x86/kvm/vmx/vmx.o
arch/x86/kvm/vmx/vmx.c:68:32: error: 'vmx_cpu_id' defined but not used [-Werror=unused-const-variable=]
   68 | static const struct x86_cpu_id vmx_cpu_id[] = {
      |                                ^~~~~~~~~~
cc1: all warnings being treated as errors

When building with =y, the MODULE_DEVICE_TABLE macro doesn't generate a
reference to the structure (or any code at all).  This makes W=1 compiles
unhappy.

Wrap both in a #ifdef to avoid the issue.

Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
[Do the same for CONFIG_KVM_AMD. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:35:37 +01:00
Wanpeng Li
8a9442f49c KVM: Pre-allocate 1 cpumask variable per cpu for both pv tlb and pv ipis
Nick Desaulniers Reported:

  When building with:
  $ make CC=clang arch/x86/ CFLAGS=-Wframe-larger-than=1000
  The following warning is observed:
  arch/x86/kernel/kvm.c:494:13: warning: stack frame size of 1064 bytes in
  function 'kvm_send_ipi_mask_allbutself' [-Wframe-larger-than=]
  static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int
  vector)
              ^
  Debugging with:
  https://github.com/ClangBuiltLinux/frame-larger-than
  via:
  $ python3 frame_larger_than.py arch/x86/kernel/kvm.o \
    kvm_send_ipi_mask_allbutself
  points to the stack allocated `struct cpumask newmask` in
  `kvm_send_ipi_mask_allbutself`. The size of a `struct cpumask` is
  potentially large, as it's CONFIG_NR_CPUS divided by BITS_PER_LONG for
  the target architecture. CONFIG_NR_CPUS for X86_64 can be as high as
  8192, making a single instance of a `struct cpumask` 1024 B.

This patch fixes it by pre-allocate 1 cpumask variable per cpu and use it for
both pv tlb and pv ipis..

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:34:25 +01:00
Wanpeng Li
a262bca3ab KVM: Introduce pv check helpers
Introduce some pv check helpers for consistency.

Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:34:19 +01:00
Christian Borntraeger
fcd07f9adc KVM: let declaration of kvm_get_running_vcpus match implementation
Sparse notices that declaration and implementation do not match:
arch/s390/kvm/../../../virt/kvm/kvm_main.c:4435:17: warning: incorrect type in return expression (different address spaces)
arch/s390/kvm/../../../virt/kvm/kvm_main.c:4435:17:    expected struct kvm_vcpu [noderef] <asn:3> **
arch/s390/kvm/../../../virt/kvm/kvm_main.c:4435:17:    got struct kvm_vcpu *[noderef] <asn:3> *

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:33:57 +01:00
Paolo Bonzini
7943f4acea KVM: SVM: allocate AVIC data structures based on kvm_amd module parameter
Even if APICv is disabled at startup, the backing page and ir_list need
to be initialized in case they are needed later.  The only case in
which this can be skipped is for userspace irqchip, and that must be
done because avic_init_backing_page dereferences vcpu->arch.apic
(which is NULL for userspace irqchip).

Tested-by: rmuncrief@humanavance.com
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=206579
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-28 10:33:17 +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
James Morse
e43f1331e2 arm64: Ask the compiler to __always_inline functions used by KVM at HYP
KVM uses some of the static-inline helpers like icache_is_vipt() from
its HYP code. This assumes the function is inlined so that the code is
mapped to EL2. The compiler may decide not to inline these, and the
out-of-line version may not be in the __hyp_text section.

Add the additional __always_ hint to these static-inlines that are used
by KVM.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200220165839.256881-4-james.morse@arm.com
2020-02-22 11:01:47 +00:00
James Morse
8c2d146ee7 KVM: arm64: Define our own swab32() to avoid a uapi static inline
KVM uses swab32() when mediating GIC MMIO accesses if the GICV is badly
aligned, and the host and guest differ in endianness.

arm64 doesn't provide a __arch_swab32(), so __fswab32() is always backed
by the macro implementation that the compiler reduces to a single
instruction. But the static-inline causes problems for KVM if the compiler
chooses not to inline this function, it may not be located in the
__hyp_text where __vgic_v2_perform_cpuif_access() needs it.

Create our own __kvm_swab32() macro that calls ___constant_swab32()
directly. This way we know it will always be inlined.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200220165839.256881-3-james.morse@arm.com
2020-02-22 11:01:47 +00:00
James Morse
5c37f1ae1c KVM: arm64: Ask the compiler to __always_inline functions used at HYP
On non VHE CPUs, KVM's __hyp_text contains code run at EL2 while the rest
of the kernel runs at EL1. This code lives in its own section with start
and end markers so we can map it to EL2.

The compiler may decide not to inline static-inline functions from the
header file. It may also decide not to put these out-of-line functions
in the same section, meaning they aren't mapped when called at EL2.

Clang-9 does exactly this with __kern_hyp_va() and a few others when
x18 is reserved for the shadow call stack. Add the additional __always_
hint to all the static-inlines that are called from a hyp file.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200220165839.256881-2-james.morse@arm.com

----
kvm_get_hyp_vector() pulls in all the regular per-cpu accessors
and this_cpu_has_cap(), fortunately its only called for VHE.
2020-02-22 11:01:47 +00:00
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
Vitaly Kuznetsov
a444326780 KVM: nVMX: clear PIN_BASED_POSTED_INTR from nested pinbased_ctls only when apicv is globally disabled
When apicv is disabled on a vCPU (e.g. by enabling KVM_CAP_HYPERV_SYNIC*),
nothing happens to VMX MSRs on the already existing vCPUs, however, all new
ones are created with PIN_BASED_POSTED_INTR filtered out. This is very
confusing and results in the following picture inside the guest:

$ rdmsr -ax 0x48d
ff00000016
7f00000016
7f00000016
7f00000016

This is observed with QEMU and 4-vCPU guest: QEMU creates vCPU0, does
KVM_CAP_HYPERV_SYNIC2 and then creates the remaining three.

L1 hypervisor may only check CPU0's controls to find out what features
are available and it will be very confused later. Switch to setting
PIN_BASED_POSTED_INTR control based on global 'enable_apicv' setting.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:05:35 +01:00
Vitaly Kuznetsov
91a5f413af KVM: nVMX: handle nested posted interrupts when apicv is disabled for L1
Even when APICv is disabled for L1 it can (and, actually, is) still
available for L2, this means we need to always call
vmx_deliver_nested_posted_interrupt() when attempting an interrupt
delivery.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:05:21 +01:00
Suravee Suthikulpanit
93fd9666c2 kvm: x86: svm: Fix NULL pointer dereference when AVIC not enabled
Launching VM w/ AVIC disabled together with pass-through device
results in NULL pointer dereference bug with the following call trace.

    RIP: 0010:svm_refresh_apicv_exec_ctrl+0x17e/0x1a0 [kvm_amd]

    Call Trace:
     kvm_vcpu_update_apicv+0x44/0x60 [kvm]
     kvm_arch_vcpu_ioctl_run+0x3f4/0x1c80 [kvm]
     kvm_vcpu_ioctl+0x3d8/0x650 [kvm]
     do_vfs_ioctl+0xaa/0x660
     ? tomoyo_file_ioctl+0x19/0x20
     ksys_ioctl+0x67/0x90
     __x64_sys_ioctl+0x1a/0x20
     do_syscall_64+0x57/0x190
     entry_SYSCALL_64_after_hwframe+0x44/0xa9

Investigation shows that this is due to the uninitialized usage of
struct vapu_svm.ir_list in the svm_set_pi_irte_mode(), which is
called from svm_refresh_apicv_exec_ctrl().

The ir_list is initialized only if AVIC is enabled. So, fixes by
adding a check if AVIC is enabled in the svm_refresh_apicv_exec_ctrl().

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206579
Fixes: 8937d76239 ("kvm: x86: svm: Add support to (de)activate posted interrupts.")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:05:20 +01:00
Xiaoyao Li
624e18f92f KVM: VMX: Add VMX_FEATURE_USR_WAIT_PAUSE
Commit 159348784f ("x86/vmx: Introduce VMX_FEATURES_*") missed
bit 26 (enable user wait and pause) of Secondary Processor-based
VM-Execution Controls.

Add VMX_FEATURE_USR_WAIT_PAUSE flag so that it shows up in /proc/cpuinfo,
and use it to define SECONDARY_EXEC_ENABLE_USR_WAIT_PAUSE to make them
uniform.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:05:19 +01:00
wanpeng li
c9dfd3fb08 KVM: nVMX: Hold KVM's srcu lock when syncing vmcs12->shadow
For the duration of mapping eVMCS, it derefences ->memslots without holding
->srcu or ->slots_lock when accessing hv assist page. This patch fixes it by
moving nested_sync_vmcs12_to_shadow to prepare_guest_switch, where the SRCU
is already taken.

It can be reproduced by running kvm's evmcs_test selftest.

  =============================
  warning: suspicious rcu usage
  5.6.0-rc1+ #53 tainted: g        w ioe
  -----------------------------
  ./include/linux/kvm_host.h:623 suspicious rcu_dereference_check() usage!

  other info that might help us debug this:

   rcu_scheduler_active = 2, debug_locks = 1
  1 lock held by evmcs_test/8507:
   #0: ffff9ddd156d00d0 (&vcpu->mutex){+.+.}, at:
kvm_vcpu_ioctl+0x85/0x680 [kvm]

  stack backtrace:
  cpu: 6 pid: 8507 comm: evmcs_test tainted: g        w ioe     5.6.0-rc1+ #53
  hardware name: dell inc. optiplex 7040/0jctf8, bios 1.4.9 09/12/2016
  call trace:
   dump_stack+0x68/0x9b
   kvm_read_guest_cached+0x11d/0x150 [kvm]
   kvm_hv_get_assist_page+0x33/0x40 [kvm]
   nested_enlightened_vmentry+0x2c/0x60 [kvm_intel]
   nested_vmx_handle_enlightened_vmptrld.part.52+0x32/0x1c0 [kvm_intel]
   nested_sync_vmcs12_to_shadow+0x439/0x680 [kvm_intel]
   vmx_vcpu_run+0x67a/0xe60 [kvm_intel]
   vcpu_enter_guest+0x35e/0x1bc0 [kvm]
   kvm_arch_vcpu_ioctl_run+0x40b/0x670 [kvm]
   kvm_vcpu_ioctl+0x370/0x680 [kvm]
   ksys_ioctl+0x235/0x850
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x77/0x780
   entry_syscall_64_after_hwframe+0x49/0xbe

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:05:03 +01:00
Miaohe Lin
7455a83276 KVM: x86: don't notify userspace IOAPIC on edge-triggered interrupt EOI
Commit 13db77347d ("KVM: x86: don't notify userspace IOAPIC on edge
EOI") said, edge-triggered interrupts don't set a bit in TMR, which means
that IOAPIC isn't notified on EOI. And var level indicates level-triggered
interrupt.
But commit 3159d36ad7 ("KVM: x86: use generic function for MSI parsing")
replace var level with irq.level by mistake. Fix it by changing irq.level
to irq.trig_mode.

Cc: stable@vger.kernel.org
Fixes: 3159d36ad7 ("KVM: x86: use generic function for MSI parsing")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-21 18:04:57 +01:00
Qian Cai
b78a8552d7 kvm/emulate: fix a -Werror=cast-function-type
arch/x86/kvm/emulate.c: In function 'x86_emulate_insn':
arch/x86/kvm/emulate.c:5686:22: error: cast between incompatible
function types from 'int (*)(struct x86_emulate_ctxt *)' to 'void
(*)(struct fastop *)' [-Werror=cast-function-type]
    rc = fastop(ctxt, (fastop_t)ctxt->execute);

Fix it by using an unnamed union of a (*execute) function pointer and a
(*fastop) function pointer.

Fixes: 3009afc6e3 ("KVM: x86: Use a typedef for fastop functions")
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-20 18:13:45 +01:00
Paolo Bonzini
147f1a1fe5 KVM: x86: fix incorrect comparison in trace event
The "u" field in the event has three states, -1/0/1.  Using u8 however means that
comparison with -1 will always fail, so change to signed char.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-20 18:13:44 +01:00
Mark Rutland
b3f15ec3d8 kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe()
With VHE, running a vCPU always requires the sequence:

1. kvm_arm_vhe_guest_enter();
2. kvm_vcpu_run_vhe();
3. kvm_arm_vhe_guest_exit()

... and as we invoke this from the shared arm/arm64 KVM code, 32-bit arm
has to provide stubs for all three functions.

To simplify the common code, and make it easier to make further
modifications to the arm64-specific portions in the near future, let's
fold kvm_arm_vhe_guest_enter() and kvm_arm_vhe_guest_exit() into
kvm_vcpu_run_vhe().

The 32-bit stubs for kvm_arm_vhe_guest_enter() and
kvm_arm_vhe_guest_exit() are removed, as they are no longer used. The
32-bit stub for kvm_vcpu_run_vhe() is left as-is.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200210114757.2889-1-mark.rutland@arm.com
2020-02-17 14:38:37 +00:00
Miaohe Lin
463bfeeead KVM: nVMX: Fix some obsolete comments and grammar error
Fix wrong variable names and grammar error in comment.

Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-17 12:52:39 +01:00
Paolo Bonzini
d970a32556 KVM: x86: fix missing prototypes
Reported with "make W=1" due to -Wmissing-prototypes.

Reported-by: Qian Cai <cai@lca.pw>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-17 12:52:38 +01:00
Paolo Bonzini
ead68df94d KVM: x86: enable -Werror
Avoid more embarrassing mistakes.  At least those that the compiler
can catch.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:15:29 +01:00
Mauro Carvalho Chehab
120881b9e8 docs: virt: guest-halt-polling.txt convert to ReST
Due to some merge conflict, this file ended being alone under
Documentation/virtual.

The file itself is almost at ReST format. Just minor
adjustments are needed:

- Adjust title markup;
- Adjust a list identation;
- add a literal block markup;
- Add some blank lines.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:08 +01:00
Mauro Carvalho Chehab
033741c6c9 docs: kvm: review-checklist.txt: rename to ReST
This file is already in ReST compatible format.
So, rename it and add to the kvm's index.rst.

While here, use the standard conversion for document titles.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:07 +01:00
Mauro Carvalho Chehab
6012d9a9fa docs: kvm: Convert timekeeping.txt to ReST format
- Use document title and chapter markups;
- Add markups for literal blocks;
- Add markups for tables;
- use :field: for field descriptions;
- Add blank lines and adjust indentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:06 +01:00
Mauro Carvalho Chehab
a9700af64e docs: kvm: Convert s390-diag.txt to ReST format
This file is almost in ReST format. Just one change was
needed:

    - Add markups for a literal block and change its indentation.

While here, use the standard markup for the document title.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:06 +01:00
Mauro Carvalho Chehab
c849d86139 docs: kvm: Convert ppc-pv.txt to ReST format
- Use document title and chapter markups;
- Add markups for tables;
- Use list markups;
- Add markups for literal blocks;
- Add blank lines.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:05 +01:00
Mauro Carvalho Chehab
320f3f74d9 docs: kvm: Convert nested-vmx.txt to ReST format
This file is almost in ReST format. Just a small set of
changes were needed:

    - Add markups for lists;
    - Add markups for a literal block;
    - Adjust whitespaces.

While here, use the standard markup for the document title.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:04 +01:00
Mauro Carvalho Chehab
037d1f92ef docs: kvm: Convert mmu.txt to ReST format
- Use document title and chapter markups;
- Add markups for tables;
- Add markups for literal blocks;
- Add blank lines and adjust indentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:03 +01:00
Mauro Carvalho Chehab
75e7fcdb4a docs: kvm: Convert locking.txt to ReST format
- Use document title and chapter markups;
- Add markups for literal blocks;
- use :field: for field descriptions;
- Add blank lines and adjust indentation.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:02 +01:00
Mauro Carvalho Chehab
5a0af4806c docs: kvm: Convert hypercalls.txt to ReST format
- Use document title and chapter markups;
- Convert tables;
- Add markups for literal blocks;
- use :field: for field descriptions;
- Add blank lines and adjust indentation

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:02 +01:00
Mauro Carvalho Chehab
cec0e48be3 docs: kvm: arm/psci.txt: convert to ReST
- Add a title for the document;
- Adjust whitespaces for it to be properly formatted after
  parsed.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:01 +01:00
Mauro Carvalho Chehab
69bf758bc8 docs: kvm: convert arm/hyp-abi.txt to ReST
- Add proper markups for titles;
- Adjust whitespaces and blank lines to match ReST
  needs;
- Mark literal blocks as such.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:10:00 +01:00
Mauro Carvalho Chehab
106ee47dc6 docs: kvm: Convert api.txt to ReST format
convert api.txt document to ReST format while trying to keep
its format as close as possible with the authors intent, and
avoid adding uneeded markups.

- Use document title and chapter markups;
- Convert tables;
- Add markups for literal blocks;
- use :field: for field descriptions;
- Add blank lines and adjust indentation

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:09:59 +01:00
Mauro Carvalho Chehab
d3b52e4976 docs: kvm: convert devices/xive.txt to ReST
- Use title markups;
- adjust indentation and add blank lines as needed;
- adjust tables to match ReST accepted formats;
- mark code blocks as such.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:09:58 +01:00
Mauro Carvalho Chehab
5cccf37974 docs: kvm: convert devices/xics.txt to ReST
- Use title markups;
- adjust indentation and add blank lines as needed;
- adjust tables to match ReST accepted formats;
- use :field: markups.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:09:58 +01:00
Mauro Carvalho Chehab
6c972ba685 docs: kvm: convert devices/vm.txt to ReST
- Use title markups;
- adjust indentation and add blank lines as needed;
- use :field: markups;
- Use cross-references;
- mark code blocks as such.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-02-12 20:09:57 +01:00