We really don't care about triggering buffer errors for this condition.
This avoids a spew of:
Buffer I/O error on dev sdc, logical block 785929, async page read
Buffer I/O error on dev sdc, logical block 759095, async page read
Buffer I/O error on dev sdc, logical block 766922, async page read
Buffer I/O error on dev sdc, logical block 17659, async page read
Buffer I/O error on dev sdc, logical block 637571, async page read
Buffer I/O error on dev sdc, logical block 39241, async page read
Buffer I/O error on dev sdc, logical block 397241, async page read
Buffer I/O error on dev sdc, logical block 763992, async page read
from -EAGAIN conditions on request allocation for async reads.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
vmx_tsc_adjust_test fails with:
IA32_TSC_ADJUST is -4294969448 (-1 * TSC_ADJUST_VALUE + -2152).
IA32_TSC_ADJUST is -4294969448 (-1 * TSC_ADJUST_VALUE + -2152).
IA32_TSC_ADJUST is 281470681738540 (65534 * TSC_ADJUST_VALUE + 4294962476).
==== Test Assertion Failure ====
x86_64/vmx_tsc_adjust_test.c:153: false
pid=19738 tid=19738 - Interrupted system call
1 0x0000000000401192: main at vmx_tsc_adjust_test.c:153
2 0x00007fe1ef8583d4: ?? ??:0
3 0x0000000000401201: _start at ??:?
Failed guest assert: (adjust <= max)
The problem is that is 'tsc_val' should be u64, not u32 or the reading
gets truncated.
Fixes: 8d7fbf01f9 ("KVM: selftests: VMX preemption timer migration test")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200601154726.261868-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Recently, I switched over from swap-file to zramswap.
When reading the Documentation/vm/zswap.rst file I fell over this typo.
The parameter is called accept_threshold_percent not accept_threhsold_percent
in /sys/module/zswap/parameters/ directory.
Fixes: 45190f01dd ("mm/zswap.c: add allocation hysteresis if pool limit is hit")
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Signed-off-by: Sedat Dilek <sedat.dilek@gmail.com>
Link: https://lore.kernel.org/r/20200601005911.31222-1-sedat.dilek@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
* acpi-processor:
ACPI: processor: idle: Allow probing on platforms with one ACPI C-state
* acpi-cppc:
ACPI: CPPC: Fix reference count leak in acpi_cppc_processor_probe()
ACPI: CPPC: Make some symbols static
* acpi-dbg:
ACPI: debug: Make two functions static
* acpi-misc:
ACPI: GED: use correct trigger type field in _Exx / _Lxx handling
ACPI: GED: add support for _Exx / _Lxx handler methods
ACPI: Delete unused proc filename macros
* acpi-pci:
ACPI: hotplug: PCI: Use the new acpi_evaluate_reg() helper
ACPI: utils: Add acpi_evaluate_reg() helper
* acpica:
ACPICA: Update version to 20200430
ACPICA: Fix required parameters for _NIG and _NIH
ACPICA: Dispatcher: add status checks
ACPICA: Disassembler: ignore AE_ALREADY_EXISTS status when parsing create operators
ACPICA: Move acpi_gbl_next_cmd_num definition to acglobal.h
ACPICA: Make acpi_protocol_lengths static
* acpi-tables:
ACPI: sleep: Put the FACS table after using it
ACPI: scan: Put SPCR and STAO table after using it
ACPI: EC: Put the ACPI table after using it
ACPI: APEI: Put the HEST table for error path
ACPI: APEI: Put the error record serialization table for error path
ACPI: APEI: Put the error injection table for error path and module exit
ACPI: APEI: Put the boot error record table after parsing
ACPI: watchdog: Put the watchdog action table after parsing
ACPI: LPIT: Put the low power idle table after using it
* pm-cpuidle:
cpuidle: Fix three reference count leaks
cpuidle: Convert Qualcomm SPM driver to a generic CPUidle driver
Documentation: ABI: make current_governer_ro as a candidate for removal
Documentation: cpuidle: update the document
cpuidle: sysfs: Remove sysfs_switch and switch attributes
cpuidle: Make cpuidle governor switchable to be the default behaviour
cpuidle: sysfs: Accept governor name with 15 characters
cpuidle: sysfs: Fix the overlap for showing available governors
cpuidle: psci: Fixup execution order when entering a domain idle state
cpuidle: sysfs: Minor coding style corrections
cpuidle: sysfs: Remove the unused define_one_r(o/w) macros
Add support for a new method for BIOS to provide the address and length
of the protected SMI communication buffer, via SMBIOS OEM strings.
Signed-off-by: Stuart Hayes <stuart.w.hayes@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Merge branch 'for-next' of
git@github.com:spandruvada/linux-kernel.git
to update Intel SST tools.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
On the ASUS laptop UX325JA/UX425JA, most of the media keys are not
working due to the ASUS WMI driver fails to be loaded. The ACPI error
as follows leads to the failure of asus_wmi_evaluate_method.
ACPI BIOS Error (bug): AE_AML_BUFFER_LIMIT, Field [IIA3] at bit offset/length 96/32 exceeds size of target Buffer (96 bits) (20200326/dsopcode-203)
No Local Variables are initialized for Method [WMNB]
ACPI Error: Aborting method \_SB.ATKD.WMNB due to previous error (AE_AML_BUFFER_LIMIT) (20200326/psparse-531)
The DSDT for the WMNB part shows that 5 DWORD required for local
variables and the 3rd variable IIA3 hit the buffer limit.
Method (WMNB, 3, Serialized)
{ ..
CreateDWordField (Arg2, Zero, IIA0)
CreateDWordField (Arg2, 0x04, IIA1)
CreateDWordField (Arg2, 0x08, IIA2)
CreateDWordField (Arg2, 0x0C, IIA3)
CreateDWordField (Arg2, 0x10, IIA4)
Local0 = (Arg1 & 0xFFFFFFFF)
If ((Local0 == 0x54494E49))
..
}
The limitation is determined by the input acpi_buffer size passed
to the wmi_evaluate_method. Since the struct bios_args is the data
structure used as input buffer by default for all ASUS WMI calls,
the size needs to be expanded to fix the problem.
Signed-off-by: Chris Chiu <chiu@endlessm.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
The HP Stream x360 11-p000nd no longer report SW_TABLET_MODE state / events
with recent kernels. This model reports a chassis-type of 10 / "Notebook"
which is not on the recently introduced chassis-type whitelist
Commit de9647efea ("platform/x86: intel-vbtn: Only activate tablet mode
switch on 2-in-1's") added a chassis-type whitelist and only listed 31 /
"Convertible" as being capable of generating valid SW_TABLET_MOD events.
Commit 1fac39fd03 ("platform/x86: intel-vbtn: Also handle tablet-mode
switch on "Detachable" and "Portable" chassis-types") extended the
whitelist with chassis-types 8 / "Portable" and 32 / "Detachable".
And now we need to exten the whitelist again with 10 / "Notebook"...
The issue original fixed by the whitelist is really a ACPI DSDT bug on
the Dell XPS 9360 where it has a VGBS which reports it is in tablet mode
even though it is not a 2-in-1 at all, but a regular laptop.
So since this is a workaround for a DSDT issue on that specific model,
instead of extending the whitelist over and over again, lets switch to
a blacklist and only blacklist the chassis-type of the model for which
the chassis-type check was added.
Note this also fixes the current version of the code no longer checking
if dmi_get_system_info(DMI_CHASSIS_TYPE) returns NULL.
Fixes: 1fac39fd03 ("platform/x86: intel-vbtn: Also handle tablet-mode switch on "Detachable" and "Portable" chassis-types")
Cc: Mario Limonciello <mario.limonciello@dell.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mario Limonciello <Mario.limonciello@dell.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
HEBC method reports capabilities of 5 button array but HP Spectre X2 (2015)
does not have this control method (the same was for Wacom MobileStudio Pro).
Expand previous DMI quirk by Alex Hung to also enable 5 button array
for this system.
Signed-off-by: Nickolai Kozachenko <daemongloom@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Add minimum values for the x and y axis, correct the max value for the
x-axis and add support for the capacitive home-button these tablets have.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This merge brings in a few fixes that I would have sent this week, had
there been a 5.7-rc8 release.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
- Move the arch-specific code into arch/arm64/kvm
- Start the post-32bit cleanup
- Cherry-pick a few non-invasive pre-NV patches
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Merge tag 'kvmarm-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 updates for Linux 5.8:
- Move the arch-specific code into arch/arm64/kvm
- Start the post-32bit cleanup
- Cherry-pick a few non-invasive pre-NV patches
The userspace_addr alignment and range checks are not performed for private
memory slots that are prepared by KVM itself. This is unnecessary and makes
it questionable to use __*_user functions to access memory later on. We also
rely on the userspace address being aligned since we have an entire family
of functions to map gfn to pfn.
Fortunately skipping the check is completely unnecessary. Only x86 uses
private memslots and their userspace_addr is obtained from vm_mmap,
therefore it must be below PAGE_OFFSET. In fact, any attempt to pass
an address above PAGE_OFFSET would have failed because such an address
would return true for kvm_is_error_hva.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Update tests to reflect new CPUID capabilities with SYNDBG.
Check that we get the right number of entries and that
0x40000000.EAX always returns the correct max leaf.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200529134543.1127440-7-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
There is another mode for the synthetic debugger which uses hypercalls
to send/recv network data instead of the MSR interface.
This interface is much slower and less recommended since you might get
a lot of VMExits while KDVM polling for new packets to recv, rather
than simply checking the pending page to see if there is data avialble
and then request.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200529134543.1127440-6-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Microsoft's kdvm.dll dbgtransport module does not respect the hypercall
page and simply identifies the CPU being used (AMD/Intel) and according
to it simply makes hypercalls with the relevant instruction
(vmmcall/vmcall respectively).
The relevant function in kdvm is KdHvConnectHypervisor which first checks
if the hypercall page has been enabled via HV_X64_MSR_HYPERCALL_ENABLE,
and in case it was not it simply sets the HV_X64_MSR_GUEST_OS_ID to
0x1000101010001 which means:
build_number = 0x0001
service_version = 0x01
minor_version = 0x01
major_version = 0x01
os_id = 0x00 (Undefined)
vendor_id = 1 (Microsoft)
os_type = 0 (A value of 0 indicates a proprietary, closed source OS)
and starts issuing the hypercall without setting the hypercall page.
To resolve this issue simply enable hypercalls also if the guest_os_id
is not 0.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200529134543.1127440-5-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add support for Hyper-V synthetic debugger (syndbg) interface.
The syndbg interface is using MSRs to emulate a way to send/recv packets
data.
The debug transport dll (kdvm/kdnet) will identify if Hyper-V is enabled
and if it supports the synthetic debugger interface it will attempt to
use it, instead of trying to initialize a network adapter.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200529134543.1127440-4-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Hyper-V synthetic debugger has two modes, one that uses MSRs and
the other that use Hypercalls.
Add all the required definitions to both types of synthetic debugger
interface.
Some of the required new CPUIDs and MSRs are not documented in the TLFS
so they are in hyperv.h instead.
The reason they are not documented is because they are subjected to be
removed in future versions of Windows.
Reviewed-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200529134543.1127440-3-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When a nested VM with a VMX-preemption timer is migrated, verify that the
nested VM and its parent VM observe the VMX-preemption timer exit close to
the original expiration deadline.
Signed-off-by: Makarand Sonare <makarandsonare@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20200526215107.205814-3-makarandsonare@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add new field to hold preemption timer expiration deadline
appended to struct kvm_vmx_nested_state_hdr. This is to prevent
the first VM-Enter after migration from incorrectly restarting the timer
with the full timer value instead of partially decayed timer value.
KVM_SET_NESTED_STATE restarts timer using migrated state regardless
of whether L1 sets VM_EXIT_SAVE_VMX_PREEMPTION_TIMER.
Fixes: cf8b84f48a ("kvm: nVMX: Prepare for checkpointing L2 state")
Signed-off-by: Peter Shier <pshier@google.com>
Signed-off-by: Makarand Sonare <makarandsonare@google.com>
Message-Id: <20200526215107.205814-2-makarandsonare@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The problem the patch is trying to address is the fact that 'struct
kvm_hyperv_exit' has different layout on when compiling in 32 and 64 bit
modes.
In 64-bit mode the default alignment boundary is 64 bits thus
forcing extra gaps after 'type' and 'msr' but in 32-bit mode the
boundary is at 32 bits thus no extra gaps.
This is an issue as even when the kernel is 64 bit, the userspace using
the interface can be both 32 and 64 bit but the same 32 bit userspace has
to work with 32 bit kernel.
The issue is fixed by forcing the 64 bit layout, this leads to ABI
change for 32 bit builds and while we are obviously breaking '32 bit
userspace with 32 bit kernel' case, we're fixing the '32 bit userspace
with 64 bit kernel' one.
As the interface has no (known) users and 32 bit KVM is rather baroque
nowadays, this seems like a reasonable decision.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200424113746.3473563-2-arilou@gmail.com>
Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Intel CPUs have a new alternative MSR range (starting from MSR_IA32_PMC0)
for GP counters that allows writing the full counter width. Enable this
range from a new capability bit (IA32_PERF_CAPABILITIES.FW_WRITE[bit 13]).
The guest would query CPUID to get the counter width, and sign extends
the counter values as needed. The traditional MSRs always limit to 32bit,
even though the counter internally is larger (48 or 57 bits).
When the new capability is set, use the alternative range which do not
have these restrictions. This lowers the overhead of perf stat slightly
because it has to do less interrupts to accumulate the counter value.
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Message-Id: <20200529074347.124619-3-like.xu@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Change kvm_pmu_get_msr() to get the msr_data struct, as the host_initiated
field from the struct could be used by get_msr. This also makes this API
consistent with kvm_pmu_set_msr. No functional changes.
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Message-Id: <20200529074347.124619-2-like.xu@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce new capability to indicate that KVM supports interrupt based
delivery of 'page ready' APF events. This includes support for both
MSR_KVM_ASYNC_PF_INT and MSR_KVM_ASYNC_PF_ACK.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200525144125.143875-8-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If two page ready notifications happen back to back the second one is not
delivered and the only mechanism we currently have is
kvm_check_async_pf_completion() check in vcpu_run() loop. The check will
only be performed with the next vmexit when it happens and in some cases
it may take a while. With interrupt based page ready notification delivery
the situation is even worse: unlike exceptions, interrupts are not handled
immediately so we must check if the slot is empty. This is slow and
unnecessary. Introduce dedicated MSR_KVM_ASYNC_PF_ACK MSR to communicate
the fact that the slot is free and host should check its notification
queue. Mandate using it for interrupt based 'page ready' APF event
delivery.
As kvm_check_async_pf_completion() is going away from vcpu_run() we need
a way to communicate the fact that vcpu->async_pf.done queue has
transitioned from empty to non-empty state. Introduce
kvm_arch_async_page_present_queued() and KVM_REQ_APF_READY to do the job.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200525144125.143875-7-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Concerns were expressed around APF delivery via synthetic #PF exception as
in some cases such delivery may collide with real page fault. For 'page
ready' notifications we can easily switch to using an interrupt instead.
Introduce new MSR_KVM_ASYNC_PF_INT mechanism and deprecate the legacy one.
One notable difference between the two mechanisms is that interrupt may not
get handled immediately so whenever we would like to deliver next event
(regardless of its type) we must be sure the guest had read and cleared
previous event in the slot.
While on it, get rid on 'type 1/type 2' names for APF events in the
documentation as they are causing confusion. Use 'page not present'
and 'page ready' everywhere instead.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200525144125.143875-6-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
An innocent reader of the following x86 KVM code:
bool kvm_arch_can_inject_async_page_present(struct kvm_vcpu *vcpu)
{
if (!(vcpu->arch.apf.msr_val & KVM_ASYNC_PF_ENABLED))
return true;
...
may get very confused: if APF mechanism is not enabled, why do we report
that we 'can inject async page present'? In reality, upon injection
kvm_arch_async_page_present() will check the same condition again and,
in case APF is disabled, will just drop the item. This is fine as the
guest which deliberately disabled APF doesn't expect to get any APF
notifications.
Rename kvm_arch_can_inject_async_page_present() to
kvm_arch_can_dequeue_async_page_present() to make it clear what we are
checking: if the item can be dequeued (meaning either injected or just
dropped).
On s390 kvm_arch_can_inject_async_page_present() always returns 'true' so
the rename doesn't matter much.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200525144125.143875-4-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, APF mechanism relies on the #PF abuse where the token is being
passed through CR2. If we switch to using interrupts to deliver page-ready
notifications we need a different way to pass the data. Extent the existing
'struct kvm_vcpu_pv_apf_data' with token information for page-ready
notifications.
While on it, rename 'reason' to 'flags'. This doesn't change the semantics
as we only have reasons '1' and '2' and these can be treated as bit flags
but KVM_PV_REASON_PAGE_READY is going away with interrupt based delivery
making 'reason' name misleading.
The newly introduced apf_put_user_ready() temporary puts both flags and
token information, this will be changed to put token only when we switch
to interrupt based notifications.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200525144125.143875-3-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 9a6e7c3981 (""KVM: async_pf: Fix #DF due to inject "Page not
Present" and "Page Ready" exceptions simultaneously") added a protection
against 'page ready' notification coming before 'page not present' is
delivered. This situation seems to be impossible since commit 2a266f2355
("KVM MMU: check pending exception before injecting APF) which added
'vcpu->arch.exception.pending' check to kvm_can_do_async_pf.
On x86, kvm_arch_async_page_present() has only one call site:
kvm_check_async_pf_completion() loop and we only enter the loop when
kvm_arch_can_inject_async_page_present(vcpu) which when async pf msr
is enabled, translates into kvm_can_do_async_pf().
There is also one problem with the cancellation mechanism. We don't seem
to check that the 'page not present' notification we're canceling matches
the 'page ready' notification so in theory, we may erroneously drop two
valid events.
Revert the commit.
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200525144125.143875-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Message-Id: <20200507185618.GA14831@embeddedor>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This reverts commit 5b494aea13.
If unlocked==true then the vma pointer could be invalidated, so the 2nd
follow_pfn() is potentially racy: we do need to get out and redo
find_vma_intersection().
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Similar to VMX, the state that is captured through the currently available
IOCTLs is a mix of L1 and L2 state, dependent on whether the L2 guest was
running at the moment when the process was interrupted to save its state.
In particular, the SVM-specific state for nested virtualization includes
the L1 saved state (including the interrupt flag), the cached L2 controls,
and the GIF.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM_CAP_NESTED_STATE is now supported for AMD too but smm test acts like
it is still Intel only.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200529130407.57176-2-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The test is similar to the existing one for VMX, but simpler because we
don't have to test shadow VMCS or vmptrld/vmptrst/vmclear.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Many tests will want to check if the CPU is Intel or AMD in
guest code, add cpu_has_svm() and put it as static
inline to svm_util.h.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200529130407.57176-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This allows fetching the registers from the hsave area when setting
up the NPT shadow MMU, and is needed for KVM_SET_NESTED_STATE (which
runs long after the CR0, CR4 and EFER values in vcpu have been switched
to hold L2 guest state).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
According to the AMD manual, the effect of turning off EFER.SVME while a
guest is running is undefined. We make it leave guest mode immediately,
similar to the effect of clearing the VMX bit in MSR_IA32_FEAT_CTL.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
