Commit Graph

697 Commits

Author SHA1 Message Date
David Woodhouse
117cc7a908 x86/retpoline: Fill return stack buffer on vmexit
In accordance with the Intel and AMD documentation, we need to overwrite
all entries in the RSB on exiting a guest, to prevent malicious branch
target predictions from affecting the host kernel. This is needed both
for retpoline and for IBRS.

[ak: numbers again for the RSB stuffing labels]

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515755487-8524-1-git-send-email-dwmw@amazon.co.uk
2018-01-12 12:33:37 +01:00
Paolo Bonzini
bd89525a82 KVM: x86: emulate #UD while in guest mode
This reverts commits ae1f576707
and ac9b305caa.

If the hardware doesn't support MOVBE, but L0 sets CPUID.01H:ECX.MOVBE
in L1's emulated CPUID information, then L1 is likely to pass that
CPUID bit through to L2. L2 will expect MOVBE to work, but if L1
doesn't intercept #UD, then any MOVBE instruction executed in L2 will
raise #UD, and the exception will be delivered in L2.

Commit ac9b305caa is a better and more
complete version of ae1f576707 ("KVM: nVMX: Do not emulate #UD while
in guest mode"); however, neither considers the above case.

Suggested-by: Jim Mattson <jmattson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-11 16:55:24 +01:00
Jim Mattson
0cb5b30698 kvm: vmx: Scrub hardware GPRs at VM-exit
Guest GPR values are live in the hardware GPRs at VM-exit.  Do not
leave any guest values in hardware GPRs after the guest GPR values are
saved to the vcpu_vmx structure.

This is a partial mitigation for CVE 2017-5715 and CVE 2017-5753.
Specifically, it defeats the Project Zero PoC for CVE 2017-5715.

Suggested-by: Eric Northup <digitaleric@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Eric Northup <digitaleric@google.com>
Reviewed-by: Benjamin Serebrin <serebrin@google.com>
Reviewed-by: Andrew Honig <ahonig@google.com>
[Paolo: Add AMD bits, Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-01-05 16:48:40 +01:00
Paolo Bonzini
66336cab35 KVM: x86: add support for emulating UMIP
The User-Mode Instruction Prevention feature present in recent Intel
processor prevents a group of instructions (sgdt, sidt, sldt, smsw, and
str) from being executed with CPL > 0. Otherwise, a general protection
fault is issued.

UMIP instructions in general are also able to trigger vmexits, so we can
actually emulate UMIP on older processors.  This commit sets up the
infrastructure so that kvm-intel.ko and kvm-amd.ko can set the UMIP
feature bit for CPUID even if the feature is not actually available
in hardware.

Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-12-14 09:26:39 +01:00
Brijesh Singh
00b10fe104 KVM: X86: Restart the guest when insn_len is zero and SEV is enabled
On AMD platforms, under certain conditions insn_len may be zero on #NPF.
This can happen if a guest gets a page-fault on data access but the HW
table walker is not able to read the instruction page (e.g instruction
page is not present in memory).

Typically, when insn_len is zero, x86_emulate_instruction() walks the
guest page table and fetches the instruction bytes from guest memory.
When SEV is enabled, the guest memory is encrypted with guest-specific
key hence hypervisor will not able to fetch the instruction bytes.
In those cases we simply restart the guest.

I have encountered this issue when running kernbench inside the guest.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2017-12-04 13:33:14 -06:00
Brijesh Singh
35c6f649bb KVM: SVM: Do not install #UD intercept when SEV is enabled
On #UD, x86_emulate_instruction() fetches the data from guest memory and
decodes the instruction bytes to assist further. When SEV is enabled, the
instruction bytes will be encrypted using the guest-specific key and the
hypervisor will no longer able to fetch the instruction bytes to assist
UD handling. By not installing intercept we let the guest receive and
handle #UD.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2017-12-04 13:33:14 -06:00
Brijesh Singh
0ede79e132 KVM: SVM: Clear C-bit from the page fault address
When SEV is active, on #VMEXIT the  page fault address will contain the
C-bit. We must clear the C-bit before handling the fault.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2017-12-04 13:33:14 -06:00
Brijesh Singh
1e80fdc09d KVM: SVM: Pin guest memory when SEV is active
The SEV memory encryption engine uses a tweak such that two identical
plaintext pages at different location will have different ciphertext.
So swapping or moving ciphertext of two pages will not result in
plaintext being swapped. Relocating (or migrating) physical backing
pages for a SEV guest will require some additional steps. The current SEV
key management spec does not provide commands to swap or migrate (move)
ciphertext pages. For now, we pin the guest memory registered through
KVM_MEMORY_ENCRYPT_REG_REGION ioctl.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2017-12-04 13:33:14 -06:00
Brijesh Singh
9f5b5b950a KVM: SVM: Add support for SEV LAUNCH_SECRET command
The command is used for injecting a secret into the guest memory region.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:33:13 -06:00
Brijesh Singh
7d1594f5d9 KVM: SVM: Add support for SEV DEBUG_ENCRYPT command
The command copies a plaintext into guest memory and encrypts it using
the VM encryption key. The command will be used for debug purposes
(e.g setting breakpoints through gdbserver)

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2017-12-04 13:33:13 -06:00
Brijesh Singh
24f41fb23a KVM: SVM: Add support for SEV DEBUG_DECRYPT command
The command is used for decrypting a guest memory region for debug
purposes.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:33:13 -06:00
Brijesh Singh
255d9e75e2 KVM: SVM: Add support for SEV GUEST_STATUS command
The command is used for querying the SEV guest information.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:33:13 -06:00
Brijesh Singh
5bdb0e2fa4 KVM: SVM: Add support for SEV LAUNCH_FINISH command
The command is used for finializing the SEV guest launch process.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:33:13 -06:00
Brijesh Singh
0d0736f763 KVM: SVM: Add support for KVM_SEV_LAUNCH_MEASURE command
The command is used to retrieve the measurement of contents encrypted
through the KVM_SEV_LAUNCH_UPDATE_DATA command.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:33:13 -06:00
Brijesh Singh
89c5058090 KVM: SVM: Add support for KVM_SEV_LAUNCH_UPDATE_DATA command
The command is used for encrypting the guest memory region using the VM
encryption key (VEK) created during KVM_SEV_LAUNCH_START.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:33:13 -06:00
Brijesh Singh
59414c9892 KVM: SVM: Add support for KVM_SEV_LAUNCH_START command
The KVM_SEV_LAUNCH_START command is used to create a memory encryption
context within the SEV firmware. In order to do so, the guest owner
should provide the guest's policy, its public Diffie-Hellman (PDH) key
and session information. The command implements the LAUNCH_START flow
defined in SEV spec Section 6.2.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:33:10 -06:00
Brijesh Singh
70cd94e60c KVM: SVM: VMRUN should use associated ASID when SEV is enabled
SEV hardware uses ASIDs to associate a memory encryption key with a
guest VM. During guest creation, a SEV VM uses the SEV_CMD_ACTIVATE
command to bind a particular ASID to the guest. Lets make sure that the
VMCB is programmed with the bound ASID before a VMRUN.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:32:30 -06:00
Brijesh Singh
1654efcbc4 KVM: SVM: Add KVM_SEV_INIT command
The command initializes the SEV platform context and allocates a new ASID
for this guest from the SEV ASID pool. The firmware must be initialized
before we issue any guest launch commands to create a new memory encryption
context.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 13:21:55 -06:00
Brijesh Singh
e9df094289 KVM: SVM: Add sev module_param
The module parameter can be used to control the SEV feature support.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 10:57:33 -06:00
Brijesh Singh
ed3cd233f8 KVM: SVM: Reserve ASID range for SEV guest
A SEV-enabled guest must use ASIDs from the defined subset, while non-SEV
guests can use the remaining ASID range. The range of allowed SEV guest
ASIDs is [1 - CPUID_8000_001F[ECX][31:0]].

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 10:57:32 -06:00
Brijesh Singh
8765d75329 KVM: X86: Extend CPUID range to include new leaf
This CPUID leaf provides the memory encryption support information on
AMD Platform. Its complete description is available in APM volume 2,
Section 15.34

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
2017-12-04 10:57:25 -06:00
Brijesh Singh
4faefff324 KVM: SVM: Prepare to reserve asid for SEV guest
Currently, ASID allocation start at 1. Add a svm_vcpu_data.min_asid
which allows supplying a dynamic start ASID.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 10:57:25 -06:00
Tom Lendacky
cea3a19b00 kvm: svm: prepare for new bit definition in nested_ctl
Currently the nested_ctl variable in the vmcb_control_area structure is
used to indicate nested paging support. The nested paging support field
is actually defined as bit 0 of the field. In order to support a new
feature flag the usage of the nested_ctl and nested paging support must
be converted to operate on a single bit.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
2017-12-04 10:57:24 -06:00
Liran Alon
61cb57c9ed KVM: x86: Exit to user-mode on #UD intercept when emulator requires
Instruction emulation after trapping a #UD exception can result in an
MMIO access, for example when emulating a MOVBE on a processor that
doesn't support the instruction.  In this case, the #UD vmexit handler
must exit to user mode, but there wasn't any code to do so.  Add it for
both VMX and SVM.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-11-17 13:20:10 +01:00
Liran Alon
ac9b305caa KVM: nVMX/nSVM: Don't intercept #UD when running L2
When running L2, #UD should be intercepted by L1 or just forwarded
directly to L2. It should not reach L0 x86 emulator.
Therefore, set intercept for #UD only based on L1 exception-bitmap.

Also add WARN_ON_ONCE() on L0 #UD intercept handlers to make sure
it is never reached while running L2.

This improves commit ae1f576707 ("KVM: nVMX: Do not emulate #UD while
in guest mode") by removing an unnecessary exit from L2 to L0 on #UD
when L1 doesn't intercept it.

In addition, SVM L0 #UD intercept handler doesn't handle correctly the
case it is raised from L2. In this case, it should forward the #UD to
guest instead of x86 emulator. As done in VMX #UD intercept handler.
This commit fixes this issue as-well.

Signed-off-by: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-11-17 13:20:09 +01:00
Paolo Bonzini
15038e1472 KVM: SVM: obey guest PAT
For many years some users of assigned devices have reported worse
performance on AMD processors with NPT than on AMD without NPT,
Intel or bare metal.

The reason turned out to be that SVM is discarding the guest PAT
setting and uses the default (PA0=PA4=WB, PA1=PA5=WT, PA2=PA6=UC-,
PA3=UC).  The guest might be using a different setting, and
especially might want write combining but isn't getting it
(instead getting slow UC or UC- accesses).

Thanks a lot to geoff@hostfission.com for noticing the relation
to the g_pat setting.  The patch has been tested also by a bunch
of people on VFIO users forums.

Fixes: 709ddebf81
Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=196409
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Tested-by: Nick Sarnie <commendsarnex@gmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-11-17 13:20:06 +01:00
Ladi Prosek
cc3d967f7e KVM: SVM: detect opening of SMI window using STGI intercept
Commit 05cade71cf ("KVM: nSVM: fix SMI injection in guest mode") made
KVM mask SMI if GIF=0 but it didn't do anything to unmask it when GIF is
enabled.

The issue manifests for me as a significantly longer boot time of Windows
guests when running with SMM-enabled OVMF.

This commit fixes it by intercepting STGI instead of requesting immediate
exit if the reason why SMM was masked is GIF.

Fixes: 05cade71cf ("KVM: nSVM: fix SMI injection in guest mode")
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-10-18 21:21:22 +02:00
Ladi Prosek
05cade71cf KVM: nSVM: fix SMI injection in guest mode
Entering SMM while running in guest mode wasn't working very well because several
pieces of the vcpu state were left set up for nested operation.

Some of the issues observed:

* L1 was getting unexpected VM exits (using L1 interception controls but running
  in SMM execution environment)
* MMU was confused (walk_mmu was still set to nested_mmu)
* INTERCEPT_SMI was not emulated for L1 (KVM never injected SVM_EXIT_SMI)

Intel SDM actually prescribes the logical processor to "leave VMX operation" upon
entering SMM in 34.14.1 Default Treatment of SMI Delivery. AMD doesn't seem to
document this but they provide fields in the SMM state-save area to stash the
current state of SVM. What we need to do is basically get out of guest mode for
the duration of SMM. All this completely transparent to L1, i.e. L1 is not given
control and no L1 observable state changes.

To avoid code duplication this commit takes advantage of the existing nested
vmexit and run functionality, perhaps at the cost of efficiency. To get out of
guest mode, nested_svm_vmexit is called, unchanged. Re-entering is performed using
enter_svm_guest_mode.

This commit fixes running Windows Server 2016 with Hyper-V enabled in a VM with
OVMF firmware (OVMF_CODE-need-smm.fd).

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-10-12 14:01:56 +02:00
Ladi Prosek
c26340651b KVM: nSVM: refactor nested_svm_vmrun
Analogous to 858e25c06f ("kvm: nVMX: Refactor nested_vmx_run()"), this commit splits
nested_svm_vmrun into two parts. The newly introduced enter_svm_guest_mode modifies the
vcpu state to transition from L1 to L2, while the code left in nested_svm_vmrun handles
the VMRUN instruction.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-10-12 14:01:56 +02:00
Ladi Prosek
72d7b374b1 KVM: x86: introduce ISA specific smi_allowed callback
Similar to NMI, there may be ISA specific reasons why an SMI cannot be
injected into the guest. This commit adds a new smi_allowed callback to
be implemented in following commits.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-10-12 14:01:55 +02:00
Ladi Prosek
0234bf8852 KVM: x86: introduce ISA specific SMM entry/exit callbacks
Entering and exiting SMM may require ISA specific handling under certain
circumstances. This commit adds two new callbacks with empty implementations.
Actual functionality will be added in following commits.

* pre_enter_smm() is to be called when injecting an SMM, before any
  SMM related vcpu state has been changed
* pre_leave_smm() is to be called when emulating the RSM instruction,
  when the vcpu is in real mode and before any SMM related vcpu state
  has been restored

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-10-12 14:01:55 +02:00
Paolo Bonzini
d000653057 KVM: SVM: limit kvm_handle_page_fault to #PF handling
It has always annoyed me a bit how SVM_EXIT_NPF is handled by
pf_interception.  This is also the only reason behind the
under-documented need_unprotect argument to kvm_handle_page_fault.
Let NPF go straight to kvm_mmu_page_fault, just like VMX
does in handle_ept_violation and handle_ept_misconfig.

Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-10-12 14:01:55 +02:00
Paolo Bonzini
1cf53587c0 KVM: SVM: unconditionally wake up VCPU on IOMMU interrupt
Checking the mode is unnecessary, and is done without a memory barrier
separating the LAPIC write from the vcpu->mode read; in addition,
kvm_vcpu_wake_up is already doing a check for waiters on the wait queue
that has the same effect.

In practice it's safe because spin_lock has full-barrier semantics on x86,
but don't be too clever.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-10-12 14:01:54 +02:00
Suravee Suthikulpanit
67034bb9dd KVM: SVM: Add irqchip_split() checks before enabling AVIC
SVM AVIC hardware accelerates guest write to APIC_EOI register
(for edge-trigger interrupt), which means it does not trap to KVM.

So, only enable SVM AVIC only in split irqchip mode.
(e.g. launching qemu w/ option '-machine kernel_irqchip=split').

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Fixes: 44a95dae1d ("KVM: x86: Detect and Initialize AVIC support")
[Removed pr_debug - Radim.]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-09-14 17:05:13 +02:00
Suravee Suthikulpanit
b2a05feff2 KVM: Add struct kvm_vcpu pointer parameter to get_enable_apicv()
Modify struct kvm_x86_ops.arch.apicv_active() to take struct kvm_vcpu
pointer as parameter in preparation to subsequent changes.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-09-13 18:29:06 +02:00
Suravee Suthikulpanit
dfa20099e2 KVM: SVM: Refactor AVIC vcpu initialization into avic_init_vcpu()
Preparing the base code for subsequent changes. This does not change
existing logic.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-09-13 18:29:06 +02:00
Jan H. Schönherr
49a8afca38 KVM: SVM: Add a missing 'break' statement
Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Fixes: f6511935f4 ("KVM: SVM: Add checks for IO instructions")
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-09-13 16:40:23 +02:00
Linus Torvalds
0756b7fbb6 First batch of KVM changes for 4.14
Common:
  - improve heuristic for boosting preempted spinlocks by ignoring VCPUs
    in user mode
 
 ARM:
  - fix for decoding external abort types from guests
 
  - added support for migrating the active priority of interrupts when
    running a GICv2 guest on a GICv3 host
 
  - minor cleanup
 
 PPC:
  - expose storage keys to userspace
 
  - merge powerpc/topic/ppc-kvm branch that contains
    find_linux_pte_or_hugepte and POWER9 thread management cleanup
 
  - merge kvm-ppc-fixes with a fix that missed 4.13 because of vacations
 
  - fixes
 
 s390:
  - merge of topic branch tlb-flushing from the s390 tree to get the
    no-dat base features
 
  - merge of kvm/master to avoid conflicts with additional sthyi fixes
 
  - wire up the no-dat enhancements in KVM
 
  - multiple epoch facility (z14 feature)
 
  - Configuration z/Architecture Mode
 
  - more sthyi fixes
 
  - gdb server range checking fix
 
  - small code cleanups
 
 x86:
  - emulate Hyper-V TSC frequency MSRs
 
  - add nested INVPCID
 
  - emulate EPTP switching VMFUNC
 
  - support Virtual GIF
 
  - support 5 level page tables
 
  - speedup nested VM exits by packing byte operations
 
  - speedup MMIO by using hardware provided physical address
 
  - a lot of fixes and cleanups, especially nested
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Merge tag 'kvm-4.14-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "First batch of KVM changes for 4.14

  Common:
   - improve heuristic for boosting preempted spinlocks by ignoring
     VCPUs in user mode

  ARM:
   - fix for decoding external abort types from guests

   - added support for migrating the active priority of interrupts when
     running a GICv2 guest on a GICv3 host

   - minor cleanup

  PPC:
   - expose storage keys to userspace

   - merge kvm-ppc-fixes with a fix that missed 4.13 because of
     vacations

   - fixes

  s390:
   - merge of kvm/master to avoid conflicts with additional sthyi fixes

   - wire up the no-dat enhancements in KVM

   - multiple epoch facility (z14 feature)

   - Configuration z/Architecture Mode

   - more sthyi fixes

   - gdb server range checking fix

   - small code cleanups

  x86:
   - emulate Hyper-V TSC frequency MSRs

   - add nested INVPCID

   - emulate EPTP switching VMFUNC

   - support Virtual GIF

   - support 5 level page tables

   - speedup nested VM exits by packing byte operations

   - speedup MMIO by using hardware provided physical address

   - a lot of fixes and cleanups, especially nested"

* tag 'kvm-4.14-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (67 commits)
  KVM: arm/arm64: Support uaccess of GICC_APRn
  KVM: arm/arm64: Extract GICv3 max APRn index calculation
  KVM: arm/arm64: vITS: Drop its_ite->lpi field
  KVM: arm/arm64: vgic: constify seq_operations and file_operations
  KVM: arm/arm64: Fix guest external abort matching
  KVM: PPC: Book3S HV: Fix memory leak in kvm_vm_ioctl_get_htab_fd
  KVM: s390: vsie: cleanup mcck reinjection
  KVM: s390: use WARN_ON_ONCE only for checking
  KVM: s390: guestdbg: fix range check
  KVM: PPC: Book3S HV: Report storage key support to userspace
  KVM: PPC: Book3S HV: Fix case where HDEC is treated as 32-bit on POWER9
  KVM: PPC: Book3S HV: Fix invalid use of register expression
  KVM: PPC: Book3S HV: Fix H_REGISTER_VPA VPA size validation
  KVM: PPC: Book3S HV: Fix setting of storage key in H_ENTER
  KVM: PPC: e500mc: Fix a NULL dereference
  KVM: PPC: e500: Fix some NULL dereferences on error
  KVM: PPC: Book3S HV: Protect updates to spapr_tce_tables list
  KVM: s390: we are always in czam mode
  KVM: s390: expose no-DAT to guest and migration support
  KVM: s390: sthyi: remove invalid guest write access
  ...
2017-09-08 15:18:36 -07:00
Radim Krčmář
5f54c8b2d4 Merge branch 'kvm-ppc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
This fix was intended for 4.13, but didn't get in because both
maintainers were on vacation.

Paul Mackerras:
 "It adds mutual exclusion between list_add_rcu and list_del_rcu calls
  on the kvm->arch.spapr_tce_tables list.  Without this, userspace could
  potentially trigger corruption of the list and cause a host crash or
  worse."
2017-09-08 14:40:43 +02:00
Linus Torvalds
b1b6f83ac9 Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 mm changes from Ingo Molnar:
 "PCID support, 5-level paging support, Secure Memory Encryption support

  The main changes in this cycle are support for three new, complex
  hardware features of x86 CPUs:

   - Add 5-level paging support, which is a new hardware feature on
     upcoming Intel CPUs allowing up to 128 PB of virtual address space
     and 4 PB of physical RAM space - a 512-fold increase over the old
     limits. (Supercomputers of the future forecasting hurricanes on an
     ever warming planet can certainly make good use of more RAM.)

     Many of the necessary changes went upstream in previous cycles,
     v4.14 is the first kernel that can enable 5-level paging.

     This feature is activated via CONFIG_X86_5LEVEL=y - disabled by
     default.

     (By Kirill A. Shutemov)

   - Add 'encrypted memory' support, which is a new hardware feature on
     upcoming AMD CPUs ('Secure Memory Encryption', SME) allowing system
     RAM to be encrypted and decrypted (mostly) transparently by the
     CPU, with a little help from the kernel to transition to/from
     encrypted RAM. Such RAM should be more secure against various
     attacks like RAM access via the memory bus and should make the
     radio signature of memory bus traffic harder to intercept (and
     decrypt) as well.

     This feature is activated via CONFIG_AMD_MEM_ENCRYPT=y - disabled
     by default.

     (By Tom Lendacky)

   - Enable PCID optimized TLB flushing on newer Intel CPUs: PCID is a
     hardware feature that attaches an address space tag to TLB entries
     and thus allows to skip TLB flushing in many cases, even if we
     switch mm's.

     (By Andy Lutomirski)

  All three of these features were in the works for a long time, and
  it's coincidence of the three independent development paths that they
  are all enabled in v4.14 at once"

* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (65 commits)
  x86/mm: Enable RCU based page table freeing (CONFIG_HAVE_RCU_TABLE_FREE=y)
  x86/mm: Use pr_cont() in dump_pagetable()
  x86/mm: Fix SME encryption stack ptr handling
  kvm/x86: Avoid clearing the C-bit in rsvd_bits()
  x86/CPU: Align CR3 defines
  x86/mm, mm/hwpoison: Clear PRESENT bit for kernel 1:1 mappings of poison pages
  acpi, x86/mm: Remove encryption mask from ACPI page protection type
  x86/mm, kexec: Fix memory corruption with SME on successive kexecs
  x86/mm/pkeys: Fix typo in Documentation/x86/protection-keys.txt
  x86/mm/dump_pagetables: Speed up page tables dump for CONFIG_KASAN=y
  x86/mm: Implement PCID based optimization: try to preserve old TLB entries using PCID
  x86: Enable 5-level paging support via CONFIG_X86_5LEVEL=y
  x86/mm: Allow userspace have mappings above 47-bit
  x86/mm: Prepare to expose larger address space to userspace
  x86/mpx: Do not allow MPX if we have mappings above 47-bit
  x86/mm: Rename tasksize_32bit/64bit to task_size_32bit/64bit()
  x86/xen: Redefine XEN_ELFNOTE_INIT_P2M using PUD_SIZE * PTRS_PER_PUD
  x86/mm/dump_pagetables: Fix printout of p4d level
  x86/mm/dump_pagetables: Generalize address normalization
  x86/boot: Fix memremap() related build failure
  ...
2017-09-04 12:21:28 -07:00
Ingo Molnar
413d63d71b Merge branch 'linus' into x86/mm to pick up fixes and to fix conflicts
Conflicts:
	arch/x86/kernel/head64.c
	arch/x86/mm/mmap.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:19:13 +02:00
Paolo Bonzini
b9dd21e104 KVM: x86: simplify handling of PKRU
Move it to struct kvm_arch_vcpu, replacing guest_pkru_valid with a
simple comparison against the host value of the register.  The write of
PKRU in addition can be skipped if the guest has not enabled the feature.
Once we do this, we need not test OSPKE in the host anymore, because
guest_CR4.PKE=1 implies host_CR4.PKE=1.

The static PKU test is kept to elide the code on older CPUs.

Suggested-by: Yang Zhang <zy107165@alibaba-inc.com>
Fixes: 1be0e61c1f
Cc: stable@vger.kernel.org
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-25 09:28:28 +02:00
Wanpeng Li
664f8e26b0 KVM: X86: Fix loss of exception which has not yet been injected
vmx_complete_interrupts() assumes that the exception is always injected,
so it can be dropped by kvm_clear_exception_queue().  However,
an exception cannot be injected immediately if it is: 1) originally
destined to a nested guest; 2) trapped to cause a vmexit; 3) happening
right after VMLAUNCH/VMRESUME, i.e. when nested_run_pending is true.

This patch applies to exceptions the same algorithm that is used for
NMIs, replacing exception.reinject with "exception.injected" (equivalent
to nmi_injected).

exception.pending now represents an exception that is queued and whose
side effects (e.g., update RFLAGS.RF or DR7) have not been applied yet.
If exception.pending is true, the exception might result in a nested
vmexit instead, too (in which case the side effects must not be applied).

exception.injected instead represents an exception that is going to be
injected into the guest at the next vmentry.

Reported-by: Radim Krčmář <rkrcmar@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-24 18:09:19 +02:00
Yu Zhang
855feb6736 KVM: MMU: Add 5 level EPT & Shadow page table support.
Extends the shadow paging code, so that 5 level shadow page
table can be constructed if VM is running in 5 level paging
mode.

Also extends the ept code, so that 5 level ept table can be
constructed if maxphysaddr of VM exceeds 48 bits. Unlike the
shadow logic, KVM should still use 4 level ept table for a VM
whose physical address width is less than 48 bits, even when
the VM is running in 5 level paging mode.

Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
[Unconditionally reset the MMU context in kvm_cpuid_update.
 Changing MAXPHYADDR invalidates the reserved bit bitmasks.
 - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-24 18:09:17 +02:00
Yu Zhang
2a7266a8f9 KVM: MMU: Rename PT64_ROOT_LEVEL to PT64_ROOT_4LEVEL.
Now we have 4 level page table and 5 level page table in 64 bits
long mode, let's rename the PT64_ROOT_LEVEL to PT64_ROOT_4LEVEL,
then we can use PT64_ROOT_5LEVEL for 5 level page table, it's
helpful to make the code more clear.

Also PT64_ROOT_MAX_LEVEL is defined as 4, so that we can just
redefine it to 5 whenever a replacement is needed for 5 level
paging.

Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-24 18:09:16 +02:00
Yu Zhang
e911eb3b34 KVM: x86: Add return value to kvm_cpuid().
Return false in kvm_cpuid() when it fails to find the cpuid
entry. Also, this routine(and its caller) is optimized with
a new argument - check_limit, so that the check_cpuid_limit()
fall back can be avoided.

Signed-off-by: Yu Zhang <yu.c.zhang@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-24 18:09:15 +02:00
Janakarajan Natarajan
640bd6e575 KVM: SVM: Enable Virtual GIF feature
Enable the Virtual GIF feature. This is done by setting bit 25 at position
60h in the vmcb.

With this feature enabled, the processor uses bit 9 at position 60h as the
virtual GIF when executing STGI/CLGI instructions.

Since the execution of STGI by the L1 hypervisor does not cause a return to
the outermost (L0) hypervisor, the enable_irq_window and enable_nmi_window
are modified.

The IRQ window will be opened even if GIF is not set, under the assumption
that on resuming the L1 hypervisor the IRQ will be held pending until the
processor executes the STGI instruction.

For the NMI window, the STGI intercept is set. This will assist in opening
the window only when GIF=1.

Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-23 18:37:37 +02:00
Denys Vlasenko
3f0d4db757 KVM: SVM: delete avic_vm_id_bitmap (2 megabyte static array)
With lightly tweaked defconfig:

    text    data     bss      dec     hex filename
11259661 5109408 2981888 19350957 12745ad vmlinux.before
11259661 5109408  884736 17253805 10745ad vmlinux.after

Only compile-tested.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: pbonzini@redhat.com
Cc: rkrcmar@redhat.com
Cc: tglx@linutronix.de
Cc: mingo@redhat.com
Cc: hpa@zytor.com
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-08-18 14:37:50 +02:00
Brijesh Singh
618232e219 KVM: x86: Avoid guest page table walk when gpa_available is set
When a guest causes a page fault which requires emulation, the
vcpu->arch.gpa_available flag is set to indicate that cr2 contains a
valid GPA.

Currently, emulator_read_write_onepage() makes use of gpa_available flag
to avoid a guest page walk for a known MMIO regions. Lets not limit
the gpa_available optimization to just MMIO region. The patch extends
the check to avoid page walk whenever gpa_available flag is set.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
[Fix EPT=0 according to Wanpeng Li's fix, plus ensure VMX also uses the
 new code. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[Moved "ret < 0" to the else brach, as per David's review. - Radim]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-08-18 14:37:49 +02:00
Borislav Petkov
5442c26995 x86/cpufeature, kvm/svm: Rename (shorten) the new "virtualized VMSAVE/VMLOAD" CPUID flag
"virtual_vmload_vmsave" is what is going to land in /proc/cpuinfo now
as per v4.13-rc4, for a single feature bit which is clearly too long.

So rename it to what it is called in the processor manual.
"v_vmsave_vmload" is a bit shorter, after all.

We could go more aggressively here but having it the same as in the
processor manual is advantageous.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Radim Krčmář <rkrcmar@redhat.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Jörg Rödel <joro@8bytes.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kvm-ML <kvm@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170801185552.GA3743@nazgul.tnic
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-11 13:42:28 +02:00
Longpeng(Mike)
de63ad4cf4 KVM: X86: implement the logic for spinlock optimization
get_cpl requires vcpu_load, so we must cache the result (whether the
vcpu was preempted when its cpl=0) in kvm_vcpu_arch.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-08 10:57:43 +02:00
Longpeng(Mike)
199b5763d3 KVM: add spinlock optimization framework
If a vcpu exits due to request a user mode spinlock, then
the spinlock-holder may be preempted in user mode or kernel mode.
(Note that not all architectures trap spin loops in user mode,
only AMD x86 and ARM/ARM64 currently do).

But if a vcpu exits in kernel mode, then the holder must be
preempted in kernel mode, so we should choose a vcpu in kernel mode
as a more likely candidate for the lock holder.

This introduces kvm_arch_vcpu_in_kernel() to decide whether the
vcpu is in kernel-mode when it's preempted.  kvm_vcpu_on_spin's
new argument says the same of the spinning VCPU.

Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-08 10:57:43 +02:00
Radim Krčmář
1b4d56b86a KVM: x86: use general helpers for some cpuid manipulation
Add guest_cpuid_clear() and use it instead of kvm_find_cpuid_entry().
Also replace some uses of kvm_find_cpuid_entry() with guest_cpuid_has().

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-07 16:16:30 +02:00
Radim Krčmář
d6321d4933 KVM: x86: generalize guest_cpuid_has_ helpers
This patch turns guest_cpuid_has_XYZ(cpuid) into guest_cpuid_has(cpuid,
X86_FEATURE_XYZ), which gets rid of many very similar helpers.

When seeing a X86_FEATURE_*, we can know which cpuid it belongs to, but
this information isn't in common code, so we recreate it for KVM.

Add some BUILD_BUG_ONs to make sure that it runs nicely.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-07 16:11:50 +02:00
Paolo Bonzini
b96fb43977 KVM: nVMX: fixes to nested virt interrupt injection
There are three issues in nested_vmx_check_exception:

1) it is not taking PFEC_MATCH/PFEC_MASK into account, as reported
by Wanpeng Li;

2) it should rebuild the interruption info and exit qualification fields
from scratch, as reported by Jim Mattson, because the values from the
L2->L0 vmexit may be invalid (e.g. if an emulated instruction causes
a page fault, the EPT misconfig's exit qualification is incorrect).

3) CR2 and DR6 should not be written for exception intercept vmexits
(CR2 only for AMD).

This patch fixes the first two and adds a comment about the last,
outlining the fix.

Cc: Jim Mattson <jmattson@google.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-08-01 22:24:17 +02:00
Tom Lendacky
d0ec49d4de kvm/x86/svm: Support Secure Memory Encryption within KVM
Update the KVM support to work with SME. The VMCB has a number of fields
where physical addresses are used and these addresses must contain the
memory encryption mask in order to properly access the encrypted memory.
Also, use the memory encryption mask when creating and using the nested
page tables.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Larry Woodman <lwoodman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Toshimitsu Kani <toshi.kani@hpe.com>
Cc: kasan-dev@googlegroups.com
Cc: kvm@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/89146eccfa50334409801ff20acd52a90fb5efcf.1500319216.git.thomas.lendacky@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 11:38:04 +02:00
Wanpeng Li
adfe20fb48 KVM: async_pf: Force a nested vmexit if the injected #PF is async_pf
Add an nested_apf field to vcpu->arch.exception to identify an async page
fault, and constructs the expected vm-exit information fields. Force a
nested VM exit from nested_vmx_check_exception() if the injected #PF is
async page fault.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-14 14:26:16 +02:00
Wanpeng Li
1261bfa326 KVM: async_pf: Add L1 guest async_pf #PF vmexit handler
This patch adds the L1 guest async page fault #PF vmexit handler, such
by L1 similar to ordinary async page fault.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
[Passed insn parameters to kvm_mmu_page_fault().]
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-14 14:25:24 +02:00
Wanpeng Li
cfcd20e5ca KVM: x86: Simplify kvm_x86_ops->queue_exception parameter list
This patch removes all arguments except the first in
kvm_x86_ops->queue_exception since they can extract the arguments from
vcpu->arch.exception themselves.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-14 14:24:28 +02:00
Janakarajan Natarajan
89c8a4984f KVM: SVM: Enable Virtual VMLOAD VMSAVE feature
Enable the Virtual VMLOAD VMSAVE feature. This is done by setting bit 1
at position B8h in the vmcb.

The processor must have nested paging enabled, be in 64-bit mode and
have support for the Virtual VMLOAD VMSAVE feature for the bit to be set
in the vmcb.

Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-12 22:38:30 +02:00
Janakarajan Natarajan
0dc92119b5 KVM: SVM: Rename lbr_ctl field in the vmcb control area
Rename the lbr_ctl variable to better reflect the purpose of the field -
provide support for virtualization extensions.

Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-12 22:38:29 +02:00
Janakarajan Natarajan
8a77e90966 KVM: SVM: Prepare for new bit definition in lbr_ctl
The lbr_ctl variable in the vmcb control area is used to enable or
disable Last Branch Record (LBR) virtualization. However, this is to be
done using only bit 0 of the variable. To correct this and to prepare
for a new feature, change the current usage to work only on a particular
bit.

Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-12 22:38:28 +02:00
Ladi Prosek
b742c1e6e7 KVM: SVM: handle singlestep exception when skipping emulated instructions
kvm_skip_emulated_instruction handles the singlestep debug exception
which is something we almost always want. This commit (specifically
the change in rdmsr_interception) makes the debug.flat KVM unit test
pass on AMD.

Two call sites still call skip_emulated_instruction directly:

* In svm_queue_exception where it's used only for moving the rip forward

* In task_switch_interception which is analogous to handle_task_switch
  in VMX

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-07-12 22:38:27 +02:00
Linus Torvalds
c136b84393 PPC:
- Better machine check handling for HV KVM
 - Ability to support guests with threads=2, 4 or 8 on POWER9
 - Fix for a race that could cause delayed recognition of signals
 - Fix for a bug where POWER9 guests could sleep with interrupts pending.
 
 ARM:
 - VCPU request overhaul
 - allow timer and PMU to have their interrupt number selected from userspace
 - workaround for Cavium erratum 30115
 - handling of memory poisonning
 - the usual crop of fixes and cleanups
 
 s390:
 - initial machine check forwarding
 - migration support for the CMMA page hinting information
 - cleanups and fixes
 
 x86:
 - nested VMX bugfixes and improvements
 - more reliable NMI window detection on AMD
 - APIC timer optimizations
 
 Generic:
 - VCPU request overhaul + documentation of common code patterns
 - kvm_stat improvements
 
 There is a small conflict in arch/s390 due to an arch-wide field rename.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "PPC:
   - Better machine check handling for HV KVM
   - Ability to support guests with threads=2, 4 or 8 on POWER9
   - Fix for a race that could cause delayed recognition of signals
   - Fix for a bug where POWER9 guests could sleep with interrupts pending.

  ARM:
   - VCPU request overhaul
   - allow timer and PMU to have their interrupt number selected from userspace
   - workaround for Cavium erratum 30115
   - handling of memory poisonning
   - the usual crop of fixes and cleanups

  s390:
   - initial machine check forwarding
   - migration support for the CMMA page hinting information
   - cleanups and fixes

  x86:
   - nested VMX bugfixes and improvements
   - more reliable NMI window detection on AMD
   - APIC timer optimizations

  Generic:
   - VCPU request overhaul + documentation of common code patterns
   - kvm_stat improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits)
  Update my email address
  kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS
  x86: kvm: mmu: use ept a/d in vmcs02 iff used in vmcs12
  kvm: x86: mmu: allow A/D bits to be disabled in an mmu
  x86: kvm: mmu: make spte mmio mask more explicit
  x86: kvm: mmu: dead code thanks to access tracking
  KVM: PPC: Book3S: Fix typo in XICS-on-XIVE state saving code
  KVM: PPC: Book3S HV: Close race with testing for signals on guest entry
  KVM: PPC: Book3S HV: Simplify dynamic micro-threading code
  KVM: x86: remove ignored type attribute
  KVM: LAPIC: Fix lapic timer injection delay
  KVM: lapic: reorganize restart_apic_timer
  KVM: lapic: reorganize start_hv_timer
  kvm: nVMX: Check memory operand to INVVPID
  KVM: s390: Inject machine check into the nested guest
  KVM: s390: Inject machine check into the guest
  tools/kvm_stat: add new interactive command 'b'
  tools/kvm_stat: add new command line switch '-i'
  tools/kvm_stat: fix error on interactive command 'g'
  KVM: SVM: suppress unnecessary NMI singlestep on GIF=0 and nested exit
  ...
2017-07-06 18:38:31 -07:00
Josh Poimboeuf
c207aee480 objtool, x86: Add several functions and files to the objtool whitelist
In preparation for an objtool rewrite which will have broader checks,
whitelist functions and files which cause problems because they do
unusual things with the stack.

These whitelists serve as a TODO list for which functions and files
don't yet have undwarf unwinder coverage.  Eventually most of the
whitelists can be removed in favor of manual CFI hint annotations or
objtool improvements.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/7f934a5d707a574bda33ea282e9478e627fb1829.1498659915.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-30 10:19:19 +02:00
Ladi Prosek
1a5e185294 KVM: SVM: suppress unnecessary NMI singlestep on GIF=0 and nested exit
enable_nmi_window is supposed to be a no-op if we know that we'll see
a VM exit by the time the NMI window opens. This commit adds two more
cases:

* We intercept stgi so we don't need to singlestep on GIF=0.

* We emulate nested vmexit so we don't need to singlestep when nested
  VM exit is required.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-27 16:35:43 +02:00
Ladi Prosek
a12713c25b KVM: SVM: don't NMI singlestep over event injection
Singlestepping is enabled by setting the TF flag and care must be
taken to not let the guest see (and reuse at an inconvenient time)
the modified rflag value. One such case is event injection, as part
of which flags are pushed on the stack and restored later on iret.

This commit disables singlestepping when we're about to inject an
event and forces an immediate exit for us to re-evaluate the NMI
related state.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-27 16:35:25 +02:00
Ladi Prosek
9b61174793 KVM: SVM: hide TF/RF flags used by NMI singlestep
These flags are used internally by SVM so it's cleaner to not leak
them to callers of svm_get_rflags. This is similar to how the TF
flag is handled on KVM_GUESTDBG_SINGLESTEP by kvm_get_rflags and
kvm_set_rflags.

Without this change, the flags may propagate from host VMCB to nested
VMCB or vice versa while singlestepping over a nested VM enter/exit,
and then get stuck in inappropriate places.

Example: NMI singlestepping is enabled while running L1 guest. The
instruction to step over is VMRUN and nested vmrun emulation stashes
rflags to hsave->save.rflags. Then if singlestepping is disabled
while still in L2, TF/RF will be cleared from the nested VMCB but the
next nested VM exit will restore them from hsave->save.rflags and
cause an unexpected DB exception.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-27 16:34:58 +02:00
Ladi Prosek
ab2f4d73eb KVM: nSVM: do not forward NMI window singlestep VM exits to L1
Nested hypervisor should not see singlestep VM exits if singlestepping
was enabled internally by KVM. Windows is particularly sensitive to this
and known to bluescreen on unexpected VM exits.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-27 16:34:47 +02:00
Ladi Prosek
4aebd0e9ca KVM: SVM: introduce disable_nmi_singlestep helper
Just moving the code to a new helper in preparation for following
commits.

Signed-off-by: Ladi Prosek <lprosek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-27 16:34:32 +02:00
Dan Carpenter
e9196cebbe KVM: Tidy the whitespace in nested_svm_check_permissions()
I moved the || to the line before.  Also I replaced some spaces with a
tab on the "return 0;" line.  It looks OK in the diff but originally
that line was only indented 7 spaces.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-06-01 11:23:11 +02:00
Roman Pen
d9c1b5431d KVM: SVM: do not zero out segment attributes if segment is unusable or not present
This is a fix for the problem [1], where VMCB.CPL was set to 0 and interrupt
was taken on userspace stack.  The root cause lies in the specific AMD CPU
behaviour which manifests itself as unusable segment attributes on SYSRET.
The corresponding work around for the kernel is the following:

61f01dd941 ("x86_64, asm: Work around AMD SYSRET SS descriptor attribute issue")

In other turn virtualization side treated unusable segment incorrectly and
restored CPL from SS attributes, which were zeroed out few lines above.

In current patch it is assured only that P bit is cleared in VMCB.save state
and segment attributes are not zeroed out if segment is not presented or is
unusable, therefore CPL can be safely restored from DPL field.

This is only one part of the fix, since QEMU side should be fixed accordingly
not to zero out attributes on its side.  Corresponding patch will follow.

[1] Message id: CAJrWOzD6Xq==b-zYCDdFLgSRMPM-NkNuTSDFEtX=7MreT45i7Q@mail.gmail.com

Signed-off-by: Roman Pen <roman.penyaev@profitbricks.com>
Signed-off-by: Mikhail Sennikovskii <mikhail.sennikovskii@profitbricks.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim KrÄmář <rkrcmar@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-06-01 11:21:17 +02:00
Gioh Kim
8eae9570d1 KVM: SVM: ignore type when setting segment registers
Commit 19bca6ab75 ("KVM: SVM: Fix cross vendor migration issue with
unusable bit") added checking type when setting unusable.
So unusable can be set if present is 0 OR type is 0.
According to the AMD processor manual, long mode ignores the type value
in segment descriptor. And type can be 0 if it is read-only data segment.
Therefore type value is not related to unusable flag.

This patch is based on linux-next v4.12.0-rc3.

Signed-off-by: Gioh Kim <gi-oh.kim@profitbricks.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-05-30 17:17:22 +02:00
Dan Carpenter
d3e7dec054 KVM: Silence underflow warning in avic_get_physical_id_entry()
Smatch complains that we check cap the upper bound of "index" but don't
check for negatives.  It's a false positive because "index" is never
negative.  But it's also simple enough to make it unsigned which makes
the code easier to audit.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-05-18 14:53:54 +02:00
Linus Torvalds
2d3e4866de * ARM: HYP mode stub supports kexec/kdump on 32-bit; improved PMU
support; virtual interrupt controller performance improvements; support
 for userspace virtual interrupt controller (slower, but necessary for
 KVM on the weird Broadcom SoCs used by the Raspberry Pi 3)
 
 * MIPS: basic support for hardware virtualization (ImgTec
 P5600/P6600/I6400 and Cavium Octeon III)
 
 * PPC: in-kernel acceleration for VFIO
 
 * s390: support for guests without storage keys; adapter interruption
 suppression
 
 * x86: usual range of nVMX improvements, notably nested EPT support for
 accessed and dirty bits; emulation of CPL3 CPUID faulting
 
 * generic: first part of VCPU thread request API; kvm_stat improvements
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "ARM:
   - HYP mode stub supports kexec/kdump on 32-bit
   - improved PMU support
   - virtual interrupt controller performance improvements
   - support for userspace virtual interrupt controller (slower, but
     necessary for KVM on the weird Broadcom SoCs used by the Raspberry
     Pi 3)

  MIPS:
   - basic support for hardware virtualization (ImgTec P5600/P6600/I6400
     and Cavium Octeon III)

  PPC:
   - in-kernel acceleration for VFIO

  s390:
   - support for guests without storage keys
   - adapter interruption suppression

  x86:
   - usual range of nVMX improvements, notably nested EPT support for
     accessed and dirty bits
   - emulation of CPL3 CPUID faulting

  generic:
   - first part of VCPU thread request API
   - kvm_stat improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (227 commits)
  kvm: nVMX: Don't validate disabled secondary controls
  KVM: put back #ifndef CONFIG_S390 around kvm_vcpu_kick
  Revert "KVM: Support vCPU-based gfn->hva cache"
  tools/kvm: fix top level makefile
  KVM: x86: don't hold kvm->lock in KVM_SET_GSI_ROUTING
  KVM: Documentation: remove VM mmap documentation
  kvm: nVMX: Remove superfluous VMX instruction fault checks
  KVM: x86: fix emulation of RSM and IRET instructions
  KVM: mark requests that need synchronization
  KVM: return if kvm_vcpu_wake_up() did wake up the VCPU
  KVM: add explicit barrier to kvm_vcpu_kick
  KVM: perform a wake_up in kvm_make_all_cpus_request
  KVM: mark requests that do not need a wakeup
  KVM: remove #ifndef CONFIG_S390 around kvm_vcpu_wake_up
  KVM: x86: always use kvm_make_request instead of set_bit
  KVM: add kvm_{test,clear}_request to replace {test,clear}_bit
  s390: kvm: Cpu model support for msa6, msa7 and msa8
  KVM: x86: remove irq disablement around KVM_SET_CLOCK/KVM_GET_CLOCK
  kvm: better MWAIT emulation for guests
  KVM: x86: virtualize cpuid faulting
  ...
2017-05-08 12:37:56 -07:00
Michael S. Tsirkin
668fffa3f8 kvm: better MWAIT emulation for guests
Guests that are heavy on futexes end up IPI'ing each other a lot. That
can lead to significant slowdowns and latency increase for those guests
when running within KVM.

If only a single guest is needed on a host, we have a lot of spare host
CPU time we can throw at the problem. Modern CPUs implement a feature
called "MWAIT" which allows guests to wake up sleeping remote CPUs without
an IPI - thus without an exit - at the expense of never going out of guest
context.

The decision whether this is something sensible to use should be up to the
VM admin, so to user space. We can however allow MWAIT execution on systems
that support it properly hardware wise.

This patch adds a CAP to user space and a KVM cpuid leaf to indicate
availability of native MWAIT execution. With that enabled, the worst a
guest can do is waste as many cycles as a "jmp ." would do, so it's not
a privilege problem.

We consciously do *not* expose the feature in our CPUID bitmap, as most
people will want to benefit from sleeping vCPUs to allow for over commit.

Reported-by: "Gabriel L. Somlo" <gsomlo@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
[agraf: fix amd, change commit message]
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-21 12:50:28 +02:00
Borislav Petkov
74f169090b kvm/svm: Setup MCG_CAP on AMD properly
MCG_CAP[63:9] bits are reserved on AMD. However, on an AMD guest, this
MSR returns 0x100010a. More specifically, bit 24 is set, which is simply
wrong. That bit is MCG_SER_P and is present only on Intel. Thus, clean
up the reserved bits in order not to confuse guests.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-07 16:49:00 +02:00
Ingo Molnar
7f75540ff2 Linux 4.11-rc5
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Merge tag 'v4.11-rc5' into x86/mm, to refresh the branch

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-04-03 16:36:32 +02:00
Dmitry Vyukov
3863dff0c3 kvm: fix usage of uninit spinlock in avic_vm_destroy()
If avic is not enabled, avic_vm_init() does nothing and returns early.
However, avic_vm_destroy() still tries to destroy what hasn't been created.
The only bad consequence of this now is that avic_vm_destroy() uses
svm_vm_data_hash_lock that hasn't been initialized (and is not meant
to be used at all if avic is not enabled).

Return early from avic_vm_destroy() if avic is not enabled.
It has nothing to destroy.

Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: kvm@vger.kernel.org
Cc: syzkaller@googlegroups.com
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2017-03-20 16:25:05 +01:00
Thomas Garnier
45fc8757d1 x86: Make the GDT remapping read-only on 64-bit
This patch makes the GDT remapped pages read-only, to prevent accidental
(or intentional) corruption of this key data structure.

This change is done only on 64-bit, because 32-bit needs it to be writable
for TSS switches.

The native_load_tr_desc function was adapted to correctly handle a
read-only GDT. The LTR instruction always writes to the GDT TSS entry.
This generates a page fault if the GDT is read-only. This change checks
if the current GDT is a remap and swap GDTs as needed. This function was
tested by booting multiple machines and checking hibernation works
properly.

KVM SVM and VMX were adapted to use the writeable GDT. On VMX, the
per-cpu variable was removed for functions to fetch the original GDT.
Instead of reloading the previous GDT, VMX will reload the fixmap GDT as
expected. For testing, VMs were started and restored on multiple
configurations.

Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Luis R . Rodriguez <mcgrof@kernel.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: kasan-dev@googlegroups.com
Cc: kernel-hardening@lists.openwall.com
Cc: kvm@vger.kernel.org
Cc: lguest@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-pm@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Cc: zijun_hu <zijun_hu@htc.com>
Link: http://lkml.kernel.org/r/20170314170508.100882-3-thgarnie@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-16 09:06:35 +01:00
Paolo Bonzini
bd7e5b0899 KVM: x86: remove code for lazy FPU handling
The FPU is always active now when running KVM.

Reviewed-by: David Matlack <dmatlack@google.com>
Reviewed-by: Bandan Das <bsd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-17 12:28:01 +01:00
David Hildenbrand
681bcea802 KVM: svm: inititalize hash table structures directly
The hashtable and guarding spinlock are global data structures,
we can inititalize them statically.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170124212116.4568-1-david@redhat.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-15 15:26:06 +01:00
Paolo Bonzini
76dfafd536 KVM: x86: do not scan IRR twice on APICv vmentry
Calls to apic_find_highest_irr are scanning IRR twice, once
in vmx_sync_pir_from_irr and once in apic_search_irr.  Change
sync_pir_from_irr to get the new maximum IRR from kvm_apic_update_irr;
now that it does the computation, it can also do the RVI write.

In order to avoid complications in svm.c, make the callback optional.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-15 14:54:35 +01:00
Tom Lendacky
0f89b207b0 kvm: svm: Use the hardware provided GPA instead of page walk
When a guest causes a NPF which requires emulation, KVM sometimes walks
the guest page tables to translate the GVA to a GPA. This is unnecessary
most of the time on AMD hardware since the hardware provides the GPA in
EXITINFO2.

The only exception cases involve string operations involving rep or
operations that use two memory locations. With rep, the GPA will only be
the value of the initial NPF and with dual memory locations we won't know
which memory address was translated into EXITINFO2.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-01-09 14:47:58 +01:00
Kyle Huey
6affcbedca KVM: x86: Add kvm_skip_emulated_instruction and use it.
kvm_skip_emulated_instruction calls both
kvm_x86_ops->skip_emulated_instruction and kvm_vcpu_check_singlestep,
skipping the emulated instruction and generating a trap if necessary.

Replacing skip_emulated_instruction calls with
kvm_skip_emulated_instruction is straightforward, except for:

- ICEBP, which is already inside a trap, so avoid triggering another trap.
- Instructions that can trigger exits to userspace, such as the IO insns,
  MOVs to CR8, and HALT. If kvm_skip_emulated_instruction does trigger a
  KVM_GUESTDBG_SINGLESTEP exit, and the handling code for
  IN/OUT/MOV CR8/HALT also triggers an exit to userspace, the latter will
  take precedence. The singlestep will be triggered again on the next
  instruction, which is the current behavior.
- Task switch instructions which would require additional handling (e.g.
  the task switch bit) and are instead left alone.
- Cases where VMLAUNCH/VMRESUME do not proceed to the next instruction,
  which do not trigger singlestep traps as mentioned previously.

Signed-off-by: Kyle Huey <khuey@kylehuey.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-12-08 15:31:05 +01:00
Kyle Huey
6a908b628c KVM: x86: Add a return value to kvm_emulate_cpuid
Once skipping the emulated instruction can potentially trigger an exit to
userspace (via KVM_GUESTDBG_SINGLESTEP) kvm_emulate_cpuid will need to
propagate a return value.

Signed-off-by: Kyle Huey <khuey@kylehuey.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-12-08 15:31:03 +01:00
Tom Lendacky
8370c3d08b kvm: svm: Add kvm_fast_pio_in support
Update the I/O interception support to add the kvm_fast_pio_in function
to speed up the in instruction similar to the out instruction.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-11-24 18:32:45 +01:00
Tom Lendacky
147277540b kvm: svm: Add support for additional SVM NPF error codes
AMD hardware adds two additional bits to aid in nested page fault handling.

Bit 32 - NPF occurred while translating the guest's final physical address
Bit 33 - NPF occurred while translating the guest page tables

The guest page tables fault indicator can be used as an aid for nested
virtualization. Using V0 for the host, V1 for the first level guest and
V2 for the second level guest, when both V1 and V2 are using nested paging
there are currently a number of unnecessary instruction emulations. When
V2 is launched shadow paging is used in V1 for the nested tables of V2. As
a result, KVM marks these pages as RO in the host nested page tables. When
V2 exits and we resume V1, these pages are still marked RO.

Every nested walk for a guest page table is treated as a user-level write
access and this causes a lot of NPFs because the V1 page tables are marked
RO in the V0 nested tables. While executing V1, when these NPFs occur KVM
sees a write to a read-only page, emulates the V1 instruction and unprotects
the page (marking it RW). This patch looks for cases where we get a NPF due
to a guest page table walk where the page was marked RO. It immediately
unprotects the page and resumes the guest, leading to far fewer instruction
emulations when nested virtualization is used.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2016-11-24 18:32:26 +01:00
Paolo Bonzini
ea26e4ec08 KVM: x86: drop TSC offsetting kvm_x86_ops to fix KVM_GET/SET_CLOCK
Since commit a545ab6a00 ("kvm: x86: add tsc_offset field to struct
kvm_vcpu_arch", 2016-09-07) the offset between host and L1 TSC is
cached and need not be fished out of the VMCS or VMCB.  This means
that we can implement adjust_tsc_offset_guest and read_l1_tsc
entirely in generic code.  The simplification is particularly
significant for VMX code, where vmx->nested.vmcs01_tsc_offset
was duplicating what is now in vcpu->arch.tsc_offset.  Therefore
the vmcs01_tsc_offset can be dropped completely.

More importantly, this fixes KVM_GET_CLOCK/KVM_SET_CLOCK
which, after commit 108b249c45 ("KVM: x86: introduce get_kvmclock_ns",
2016-09-01) called read_l1_tsc while the VMCS was not loaded.
It thus returned bogus values on Intel CPUs.

Fixes: 108b249c45
Reported-by: Roman Kagan <rkagan@virtuozzo.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-11-02 20:03:07 +01:00
Linus Torvalds
6218590bcb KVM updates for v4.9-rc1
All architectures:
   Move `make kvmconfig` stubs from x86;  use 64 bits for debugfs stats.
 
 ARM:
   Important fixes for not using an in-kernel irqchip; handle SError
   exceptions and present them to guests if appropriate; proxying of GICV
   access at EL2 if guest mappings are unsafe; GICv3 on AArch32 on ARMv8;
   preparations for GICv3 save/restore, including ABI docs; cleanups and
   a bit of optimizations.
 
 MIPS:
   A couple of fixes in preparation for supporting MIPS EVA host kernels;
   MIPS SMP host & TLB invalidation fixes.
 
 PPC:
   Fix the bug which caused guests to falsely report lockups; other minor
   fixes; a small optimization.
 
 s390:
   Lazy enablement of runtime instrumentation; up to 255 CPUs for nested
   guests; rework of machine check deliver; cleanups and fixes.
 
 x86:
   IOMMU part of AMD's AVIC for vmexit-less interrupt delivery; Hyper-V
   TSC page; per-vcpu tsc_offset in debugfs; accelerated INS/OUTS in
   nVMX; cleanups and fixes.
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Merge tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Radim Krčmář:
 "All architectures:
   - move `make kvmconfig` stubs from x86
   - use 64 bits for debugfs stats

  ARM:
   - Important fixes for not using an in-kernel irqchip
   - handle SError exceptions and present them to guests if appropriate
   - proxying of GICV access at EL2 if guest mappings are unsafe
   - GICv3 on AArch32 on ARMv8
   - preparations for GICv3 save/restore, including ABI docs
   - cleanups and a bit of optimizations

  MIPS:
   - A couple of fixes in preparation for supporting MIPS EVA host
     kernels
   - MIPS SMP host & TLB invalidation fixes

  PPC:
   - Fix the bug which caused guests to falsely report lockups
   - other minor fixes
   - a small optimization

  s390:
   - Lazy enablement of runtime instrumentation
   - up to 255 CPUs for nested guests
   - rework of machine check deliver
   - cleanups and fixes

  x86:
   - IOMMU part of AMD's AVIC for vmexit-less interrupt delivery
   - Hyper-V TSC page
   - per-vcpu tsc_offset in debugfs
   - accelerated INS/OUTS in nVMX
   - cleanups and fixes"

* tag 'kvm-4.9-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (140 commits)
  KVM: MIPS: Drop dubious EntryHi optimisation
  KVM: MIPS: Invalidate TLB by regenerating ASIDs
  KVM: MIPS: Split kernel/user ASID regeneration
  KVM: MIPS: Drop other CPU ASIDs on guest MMU changes
  KVM: arm/arm64: vgic: Don't flush/sync without a working vgic
  KVM: arm64: Require in-kernel irqchip for PMU support
  KVM: PPC: Book3s PR: Allow access to unprivileged MMCR2 register
  KVM: PPC: Book3S PR: Support 64kB page size on POWER8E and POWER8NVL
  KVM: PPC: Book3S: Remove duplicate setting of the B field in tlbie
  KVM: PPC: BookE: Fix a sanity check
  KVM: PPC: Book3S HV: Take out virtual core piggybacking code
  KVM: PPC: Book3S: Treat VTB as a per-subcore register, not per-thread
  ARM: gic-v3: Work around definition of gic_write_bpr1
  KVM: nVMX: Fix the NMI IDT-vectoring handling
  KVM: VMX: Enable MSR-BASED TPR shadow even if APICv is inactive
  KVM: nVMX: Fix reload apic access page warning
  kvmconfig: add virtio-gpu to config fragment
  config: move x86 kvm_guest.config to a common location
  arm64: KVM: Remove duplicating init code for setting VMID
  ARM: KVM: Support vgic-v3
  ...
2016-10-06 10:49:01 -07:00
Colin Ian King
adad0d02a7 kvm: svm: fix unsigned compare less than zero comparison
vm_data->avic_vm_id is a u32, so the check for a error
return (less than zero) such as -EAGAIN from
avic_get_next_vm_id currently has no effect whatsoever.
Fix this by using a temporary int for the comparison
and assign vm_data->avic_vm_id to this. I used an explicit
u32 cast in the assignment to show why vm_data->avic_vm_id
cannot be used in the assign/compare steps.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-20 09:26:30 +02:00
Luiz Capitulino
3e3f50262e kvm: x86: drop read_tsc_offset()
The TSC offset can now be read directly from struct kvm_arch_vcpu.

Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-16 16:57:45 +02:00
Suravee Suthikulpanit
411b44ba80 svm: Implements update_pi_irte hook to setup posted interrupt
This patch implements update_pi_irte function hook to allow SVM
communicate to IOMMU driver regarding how to set up IRTE for handling
posted interrupt.

In case AVIC is enabled, during vcpu_load/unload, SVM needs to update
IOMMU IRTE with appropriate host physical APIC ID. Also, when
vcpu_blocking/unblocking, SVM needs to update the is-running bit in
the IOMMU IRTE. Both are achieved via calling amd_iommu_update_ga().

However, if GA mode is not enabled for the pass-through device,
IOMMU driver will simply just return when calling amd_iommu_update_ga.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-08 13:18:58 +02:00
Suravee Suthikulpanit
5881f73757 svm: Introduce AMD IOMMU avic_ga_log_notifier
This patch introduces avic_ga_log_notifier, which will be called
by IOMMU driver whenever it handles the Guest vAPIC (GA) log entry.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-08 13:11:56 +02:00
Suravee Suthikulpanit
5ea11f2b31 svm: Introduces AVIC per-VM ID
Introduces per-VM AVIC ID and helper functions to manage the IDs.
Currently, the ID will be used to implement 32-bit AVIC IOMMU GA tag.

The ID is 24-bit one-based indexing value, and is managed via helper
functions to get the next ID, or to free an ID once a VM is destroyed.
There should be no ID conflict for any active VMs.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-09-08 12:57:20 +02:00
Kees Cook
404f6aac9b x86: Apply more __ro_after_init and const
Guided by grsecurity's analogous __read_only markings in arch/x86,
this applies several uses of __ro_after_init to structures that are
only updated during __init, and const for some structures that are
never updated.  Additionally extends __init markings to some functions
that are only used during __init, and cleans up some missing C99 style
static initializers.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brad Spengler <spender@grsecurity.net>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: David Brown <david.brown@linaro.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Emese Revfy <re.emese@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathias Krause <minipli@googlemail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: PaX Team <pageexec@freemail.hu>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20160808232906.GA29731@www.outflux.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-08-10 14:55:05 +02:00
Linus Torvalds
221bb8a46e - ARM: GICv3 ITS emulation and various fixes. Removal of the old
VGIC implementation.
 
 - s390: support for trapping software breakpoints, nested virtualization
 (vSIE), the STHYI opcode, initial extensions for CPU model support.
 
 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots of cleanups,
 preliminary to this and the upcoming support for hardware virtualization
 extensions.
 
 - x86: support for execute-only mappings in nested EPT; reduced vmexit
 latency for TSC deadline timer (by about 30%) on Intel hosts; support for
 more than 255 vCPUs.
 
 - PPC: bugfixes.
 
 The ugly bit is the conflicts.  A couple of them are simple conflicts due
 to 4.7 fixes, but most of them are with other trees. There was definitely
 too much reliance on Acked-by here.  Some conflicts are for KVM patches
 where _I_ gave my Acked-by, but the worst are for this pull request's
 patches that touch files outside arch/*/kvm.  KVM submaintainers should
 probably learn to synchronize better with arch maintainers, with the
 latter providing topic branches whenever possible instead of Acked-by.
 This is what we do with arch/x86.  And I should learn to refuse pull
 requests when linux-next sends scary signals, even if that means that
 submaintainers have to rebase their branches.
 
 Anyhow, here's the list:
 
 - arch/x86/kvm/vmx.c: handle_pcommit and EXIT_REASON_PCOMMIT was removed
 by the nvdimm tree.  This tree adds handle_preemption_timer and
 EXIT_REASON_PREEMPTION_TIMER at the same place.  In general all mentions
 of pcommit have to go.
 
 There is also a conflict between a stable fix and this patch, where the
 stable fix removed the vmx_create_pml_buffer function and its call.
 
 - virt/kvm/kvm_main.c: kvm_cpu_notifier was removed by the hotplug tree.
 This tree adds kvm_io_bus_get_dev at the same place.
 
 - virt/kvm/arm/vgic.c: a few final bugfixes went into 4.7 before the
 file was completely removed for 4.8.
 
 - include/linux/irqchip/arm-gic-v3.h: this one is entirely our fault;
 this is a change that should have gone in through the irqchip tree and
 pulled by kvm-arm.  I think I would have rejected this kvm-arm pull
 request.  The KVM version is the right one, except that it lacks
 GITS_BASER_PAGES_SHIFT.
 
 - arch/powerpc: what a mess.  For the idle_book3s.S conflict, the KVM
 tree is the right one; everything else is trivial.  In this case I am
 not quite sure what went wrong.  The commit that is causing the mess
 (fd7bacbca4, "KVM: PPC: Book3S HV: Fix TB corruption in guest exit
 path on HMI interrupt", 2016-05-15) touches both arch/powerpc/kernel/
 and arch/powerpc/kvm/.  It's large, but at 396 insertions/5 deletions
 I guessed that it wasn't really possible to split it and that the 5
 deletions wouldn't conflict.  That wasn't the case.
 
 - arch/s390: also messy.  First is hypfs_diag.c where the KVM tree
 moved some code and the s390 tree patched it.  You have to reapply the
 relevant part of commits 6c22c98637, plus all of e030c1125e, to
 arch/s390/kernel/diag.c.  Or pick the linux-next conflict
 resolution from http://marc.info/?l=kvm&m=146717549531603&w=2.
 Second, there is a conflict in gmap.c between a stable fix and 4.8.
 The KVM version here is the correct one.
 
 I have pushed my resolution at refs/heads/merge-20160802 (commit
 3d1f53419842) at git://git.kernel.org/pub/scm/virt/kvm/kvm.git.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:

 - ARM: GICv3 ITS emulation and various fixes.  Removal of the
   old VGIC implementation.

 - s390: support for trapping software breakpoints, nested
   virtualization (vSIE), the STHYI opcode, initial extensions
   for CPU model support.

 - MIPS: support for MIPS64 hosts (32-bit guests only) and lots
   of cleanups, preliminary to this and the upcoming support for
   hardware virtualization extensions.

 - x86: support for execute-only mappings in nested EPT; reduced
   vmexit latency for TSC deadline timer (by about 30%) on Intel
   hosts; support for more than 255 vCPUs.

 - PPC: bugfixes.

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (302 commits)
  KVM: PPC: Introduce KVM_CAP_PPC_HTM
  MIPS: Select HAVE_KVM for MIPS64_R{2,6}
  MIPS: KVM: Reset CP0_PageMask during host TLB flush
  MIPS: KVM: Fix ptr->int cast via KVM_GUEST_KSEGX()
  MIPS: KVM: Sign extend MFC0/RDHWR results
  MIPS: KVM: Fix 64-bit big endian dynamic translation
  MIPS: KVM: Fail if ebase doesn't fit in CP0_EBase
  MIPS: KVM: Use 64-bit CP0_EBase when appropriate
  MIPS: KVM: Set CP0_Status.KX on MIPS64
  MIPS: KVM: Make entry code MIPS64 friendly
  MIPS: KVM: Use kmap instead of CKSEG0ADDR()
  MIPS: KVM: Use virt_to_phys() to get commpage PFN
  MIPS: Fix definition of KSEGX() for 64-bit
  KVM: VMX: Add VMCS to CPU's loaded VMCSs before VMPTRLD
  kvm: x86: nVMX: maintain internal copy of current VMCS
  KVM: PPC: Book3S HV: Save/restore TM state in H_CEDE
  KVM: PPC: Book3S HV: Pull out TM state save/restore into separate procedures
  KVM: arm64: vgic-its: Simplify MAPI error handling
  KVM: arm64: vgic-its: Make vgic_its_cmd_handle_mapi similar to other handlers
  KVM: arm64: vgic-its: Turn device_id validation into generic ID validation
  ...
2016-08-02 16:11:27 -04:00
Paolo Bonzini
f2485b3e0c KVM: x86: use guest_exit_irqoff
This gains a few clock cycles per vmexit.  On Intel there is no need
anymore to enable the interrupts in vmx_handle_external_intr, since
we are using the "acknowledge interrupt on exit" feature.  AMD
needs to do that, and must be careful to avoid the interrupt shadow.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-07-01 11:03:38 +02:00
Suravee Suthikulpanit
5b8abf1f33 kvm: svm: Do not support AVIC if not CONFIG_X86_LOCAL_APIC
Add logic to disable AVIC #ifndef CONFIG_X86_LOCAL_APIC.

Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 00:28:30 +02:00
Suravee Suthikulpanit
7d669f5084 kvm: svm: Fix implicit declaration for __default_cpu_present_to_apicid()
The commit 8221c13700 ("svm: Manage vcpu load/unload when enable AVIC")
introduces a build error due to implicit function declaration
when #ifdef CONFIG_X86_32 and #ifndef CONFIG_X86_LOCAL_APIC
(as reported by Kbuild test robot i386-randconfig-x0-06121009).

So, this patch introduces kvm_cpu_get_apicid() wrapper
around __default_cpu_present_to_apicid() with additional
handling if CONFIG_X86_LOCAL_APIC is not defined.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Fixes: commit 8221c13700 ("svm: Manage vcpu load/unload when enable AVIC")
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-16 00:28:24 +02:00
Andrea Gelmini
bb3541f175 KVM: x86: Fix typos
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-06-14 11:16:28 +02:00
Linus Torvalds
e28e909c36 - move kvm_stat tool from QEMU repo into tools/kvm/kvm_stat
(kvm_stat had nothing to do with QEMU in the first place -- the tool
    only interprets debugfs)
 - expose per-vm statistics in debugfs and support them in kvm_stat
   (KVM always collected per-vm statistics, but they were summarised into
    global statistics)
 
 x86:
  - fix dynamic APICv (VMX was improperly configured and a guest could
    access host's APIC MSRs, CVE-2016-4440)
  - minor fixes
 
 ARM changes from Christoffer Dall:
  "This set of changes include the new vgic, which is a reimplementation
   of our horribly broken legacy vgic implementation.  The two
   implementations will live side-by-side (with the new being the
   configured default) for one kernel release and then we'll remove the
   legacy one.
 
   Also fixes a non-critical issue with virtual abort injection to
   guests."
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull second batch of KVM updates from Radim Krčmář:
 "General:

   - move kvm_stat tool from QEMU repo into tools/kvm/kvm_stat (kvm_stat
     had nothing to do with QEMU in the first place -- the tool only
     interprets debugfs)

   - expose per-vm statistics in debugfs and support them in kvm_stat
     (KVM always collected per-vm statistics, but they were summarised
     into global statistics)

  x86:

   - fix dynamic APICv (VMX was improperly configured and a guest could
     access host's APIC MSRs, CVE-2016-4440)

   - minor fixes

  ARM changes from Christoffer Dall:

   - new vgic reimplementation of our horribly broken legacy vgic
     implementation.  The two implementations will live side-by-side
     (with the new being the configured default) for one kernel release
     and then we'll remove the legacy one.

   - fix for a non-critical issue with virtual abort injection to guests"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (70 commits)
  tools: kvm_stat: Add comments
  tools: kvm_stat: Introduce pid monitoring
  KVM: Create debugfs dir and stat files for each VM
  MAINTAINERS: Add kvm tools
  tools: kvm_stat: Powerpc related fixes
  tools: Add kvm_stat man page
  tools: Add kvm_stat vm monitor script
  kvm:vmx: more complete state update on APICv on/off
  KVM: SVM: Add more SVM_EXIT_REASONS
  KVM: Unify traced vector format
  svm: bitwise vs logical op typo
  KVM: arm/arm64: vgic-new: Synchronize changes to active state
  KVM: arm/arm64: vgic-new: enable build
  KVM: arm/arm64: vgic-new: implement mapped IRQ handling
  KVM: arm/arm64: vgic-new: Wire up irqfd injection
  KVM: arm/arm64: vgic-new: Add vgic_v2/v3_enable
  KVM: arm/arm64: vgic-new: vgic_init: implement map_resources
  KVM: arm/arm64: vgic-new: vgic_init: implement vgic_init
  KVM: arm/arm64: vgic-new: vgic_init: implement vgic_create
  KVM: arm/arm64: vgic-new: vgic_init: implement kvm_vgic_hyp_init
  ...
2016-05-27 13:41:54 -07:00
Dan Carpenter
5446a979e0 svm: bitwise vs logical op typo
These were supposed to be a bitwise operation but there is a typo.
The result is mostly harmless, but sparse correctly complains.

Fixes: 44a95dae1d ('KVM: x86: Detect and Initialize AVIC support')
Fixes: 18f40c53e1 ('svm: Add VMEXIT handlers for AVIC')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-24 12:11:05 +02:00
Linus Torvalds
7beaa24ba4 Small release overall.
- x86: miscellaneous fixes, AVIC support (local APIC virtualization,
 AMD version)
 
 - s390: polling for interrupts after a VCPU goes to halted state is
 now enabled for s390; use hardware provided information about facility
 bits that do not need any hypervisor activity, and other fixes for
 cpu models and facilities; improve perf output; floating interrupt
 controller improvements.
 
 - MIPS: miscellaneous fixes
 
 - PPC: bugfixes only
 
 - ARM: 16K page size support, generic firmware probing layer for
 timer and GIC
 
 Christoffer Dall (KVM-ARM maintainer) says:
 "There are a few changes in this pull request touching things outside
  KVM, but they should all carry the necessary acks and it made the
  merge process much easier to do it this way."
 
 though actually the irqchip maintainers' acks didn't make it into the
 patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
 later acked at http://mid.gmane.org/573351D1.4060303@arm.com
 "more formally and for documentation purposes".
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Small release overall.

  x86:
   - miscellaneous fixes
   - AVIC support (local APIC virtualization, AMD version)

  s390:
   - polling for interrupts after a VCPU goes to halted state is now
     enabled for s390
   - use hardware provided information about facility bits that do not
     need any hypervisor activity, and other fixes for cpu models and
     facilities
   - improve perf output
   - floating interrupt controller improvements.

  MIPS:
   - miscellaneous fixes

  PPC:
   - bugfixes only

  ARM:
   - 16K page size support
   - generic firmware probing layer for timer and GIC

  Christoffer Dall (KVM-ARM maintainer) says:
    "There are a few changes in this pull request touching things
     outside KVM, but they should all carry the necessary acks and it
     made the merge process much easier to do it this way."

  though actually the irqchip maintainers' acks didn't make it into the
  patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
  later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more
  formally and for documentation purposes')"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits)
  KVM: MTRR: remove MSR 0x2f8
  KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same
  svm: Manage vcpu load/unload when enable AVIC
  svm: Do not intercept CR8 when enable AVIC
  svm: Do not expose x2APIC when enable AVIC
  KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore
  svm: Add VMEXIT handlers for AVIC
  svm: Add interrupt injection via AVIC
  KVM: x86: Detect and Initialize AVIC support
  svm: Introduce new AVIC VMCB registers
  KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick
  KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks
  KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks
  KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg
  KVM: x86: Misc LAPIC changes to expose helper functions
  KVM: shrink halt polling even more for invalid wakeups
  KVM: s390: set halt polling to 80 microseconds
  KVM: halt_polling: provide a way to qualify wakeups during poll
  KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts
  kvm: Conditionally register IRQ bypass consumer
  ...
2016-05-19 11:27:09 -07:00
Paolo Bonzini
67c9dddc95 KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same
Neither APICv nor AVIC actually need the first argument of
hwapic_isr_update, but the vCPU makes more sense than passing the
pointer to the whole virtual machine!  In fact in the APICv case it's
just happening that the vCPU is used implicitly, through the loaded VMCS.

The second argument instead is named differently, make it consistent.

Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:32 +02:00
Suravee Suthikulpanit
8221c13700 svm: Manage vcpu load/unload when enable AVIC
When a vcpu is loaded/unloaded to a physical core, we need to update
host physical APIC ID information in the Physical APIC-ID table
accordingly.

Also, when vCPU is blocking/un-blocking (due to halt instruction),
we need to make sure that the is-running bit in set accordingly in the
physical APIC-ID table.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
[Return void from new functions, add WARN_ON when they returned negative
 errno; split load and put into separate function as they have almost
 nothing in common. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:31 +02:00
Suravee Suthikulpanit
3bbf3565f4 svm: Do not intercept CR8 when enable AVIC
When enable AVIC:
    * Do not intercept CR8 since this should be handled by AVIC HW.
    * Also, we don't need to sync cr8/V_TPR and APIC backing page.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
[Rename svm_in_nested_interrupt_shadow to svm_nested_virtualize_tpr. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:31 +02:00
Suravee Suthikulpanit
46781eae2e svm: Do not expose x2APIC when enable AVIC
Since AVIC only virtualizes xAPIC hardware for the guest, this patch
disable x2APIC support in guest CPUID.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:30 +02:00
Suravee Suthikulpanit
be8ca170ed KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore
Adding kvm_x86_ops hooks to allow APICv to do post state restore.
This is required to support VM save and restore feature.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:30 +02:00
Suravee Suthikulpanit
18f40c53e1 svm: Add VMEXIT handlers for AVIC
This patch introduces VMEXIT handlers, avic_incomplete_ipi_interception()
and avic_unaccelerated_access_interception() along with two trace points
(trace_kvm_avic_incomplete_ipi and trace_kvm_avic_unaccelerated_access).

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:29 +02:00
Suravee Suthikulpanit
340d3bc366 svm: Add interrupt injection via AVIC
This patch introduces a new mechanism to inject interrupt using AVIC.
Since VINTR is not supported when enable AVIC, we need to inject
interrupt via APIC backing page instead.

This patch also adds support for AVIC doorbell, which is used by
KVM to signal a running vcpu to check IRR for injected interrupts.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:29 +02:00
Suravee Suthikulpanit
44a95dae1d KVM: x86: Detect and Initialize AVIC support
This patch introduces AVIC-related data structure, and AVIC
initialization code.

There are three main data structures for AVIC:
    * Virtual APIC (vAPIC) backing page (per-VCPU)
    * Physical APIC ID table (per-VM)
    * Logical APIC ID table (per-VM)

Currently, AVIC is disabled by default. Users can manually
enable AVIC via kernel boot option kvm-amd.avic=1 or during
kvm-amd module loading with parameter avic=1.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
[Avoid extra indentation (Boris). - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-18 18:04:28 +02:00
Andy Lutomirski
296f781a4b x86/asm/64: Rename thread_struct's fs and gs to fsbase and gsbase
Unlike ds and es, these are base addresses, not selectors.  Rename
them so their meaning is more obvious.

On x86_32, the field is still called fs.  Fixing that could make sense
as a future cleanup.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/69a18a51c4cba0ce29a241e570fc618ad721d908.1461698311.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-04-29 11:56:42 +02:00
Huaitong Han
be94f6b710 KVM, pkeys: add pkeys support for permission_fault
Protection keys define a new 4-bit protection key field (PKEY) in bits
62:59 of leaf entries of the page tables, the PKEY is an index to PKRU
register(16 domains), every domain has 2 bits(write disable bit, access
disable bit).

Static logic has been produced in update_pkru_bitmask, dynamic logic need
read pkey from page table entries, get pkru value, and deduce the correct
result.

[ Huaitong: Xiao helps to modify many sections. ]

Signed-off-by: Huaitong Han <huaitong.han@intel.com>
Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 16:23:37 +01:00
Andrey Smetanin
0d9c055eaa kvm/x86: Pass return code of kvm_emulate_hypercall
Pass the return code from kvm_emulate_hypercall on to the caller,
in order to allow it to indicate to the userspace that
the hypercall has to be handled there.

Also adjust all the existing code paths to return 1 to make sure the
hypercall isn't passed to the userspace without setting kvm_run
appropriately.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Joerg Roedel <joro@8bytes.org>
CC: "K. Y. Srinivasan" <kys@microsoft.com>
CC: Haiyang Zhang <haiyangz@microsoft.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16 18:48:41 +01:00
Linus Torvalds
1baa5efbeb * s390: Support for runtime instrumentation within guests,
support of 248 VCPUs.
 
 * ARM: rewrite of the arm64 world switch in C, support for
 16-bit VM identifiers.  Performance counter virtualization
 missed the boat.
 
 * x86: Support for more Hyper-V features (synthetic interrupt
 controller), MMU cleanups
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "PPC changes will come next week.

   - s390: Support for runtime instrumentation within guests, support of
     248 VCPUs.

   - ARM: rewrite of the arm64 world switch in C, support for 16-bit VM
     identifiers.  Performance counter virtualization missed the boat.

   - x86: Support for more Hyper-V features (synthetic interrupt
     controller), MMU cleanups"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (115 commits)
  kvm: x86: Fix vmwrite to SECONDARY_VM_EXEC_CONTROL
  kvm/x86: Hyper-V SynIC timers tracepoints
  kvm/x86: Hyper-V SynIC tracepoints
  kvm/x86: Update SynIC timers on guest entry only
  kvm/x86: Skip SynIC vector check for QEMU side
  kvm/x86: Hyper-V fix SynIC timer disabling condition
  kvm/x86: Reorg stimer_expiration() to better control timer restart
  kvm/x86: Hyper-V unify stimer_start() and stimer_restart()
  kvm/x86: Drop stimer_stop() function
  kvm/x86: Hyper-V timers fix incorrect logical operation
  KVM: move architecture-dependent requests to arch/
  KVM: renumber vcpu->request bits
  KVM: document which architecture uses each request bit
  KVM: Remove unused KVM_REQ_KICK to save a bit in vcpu->requests
  kvm: x86: Check kvm_write_guest return value in kvm_write_wall_clock
  KVM: s390: implement the RI support of guest
  kvm/s390: drop unpaired smp_mb
  kvm: x86: fix comment about {mmu,nested_mmu}.gva_to_gpa
  KVM: x86: MMU: Use clear_page() instead of init_shadow_page_table()
  arm/arm64: KVM: Detect vGIC presence at runtime
  ...
2016-01-12 13:22:12 -08:00
Linus Torvalds
671d5532aa Merge branch 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Improved CPU ID handling code and related enhancements (Borislav
     Petkov)

   - RDRAND fix (Len Brown)"

* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Replace RDRAND forced-reseed with simple sanity check
  x86/MSR: Chop off lower 32-bit value
  x86/cpu: Fix MSR value truncation issue
  x86/cpu/amd, kvm: Satisfy guest kernel reads of IC_CFG MSR
  kvm: Add accessors for guest CPU's family, model, stepping
  x86/cpu: Unify CPU family, model, stepping calculation
2016-01-11 16:46:20 -08:00
Paolo Bonzini
8b89fe1f6c kvm: x86: move tracepoints outside extended quiescent state
Invoking tracepoints within kvm_guest_enter/kvm_guest_exit causes a
lockdep splat.

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-12-11 12:26:33 +01:00
Paolo Bonzini
46896c73c1 KVM: svm: add support for RDTSCP
RDTSCP was never supported for AMD CPUs, which nobody noticed because
Linux does not use it.  But exactly the fact that Linux does not
use it makes the implementation very simple; we can freely trash
MSR_TSC_AUX while running the guest.

Cc: Joerg Roedel <joro@8bytes.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:22 +01:00
Andrey Smetanin
d62caabb41 kvm/x86: per-vcpu apicv deactivation support
The decision on whether to use hardware APIC virtualization used to be
taken globally, based on the availability of the feature in the CPU
and the value of a module parameter.

However, under certain circumstances we want to control it on per-vcpu
basis.  In particular, when the userspace activates HyperV synthetic
interrupt controller (SynIC), APICv has to be disabled as it's
incompatible with SynIC auto-EOI behavior.

To achieve that, introduce 'apicv_active' flag on struct
kvm_vcpu_arch, and kvm_vcpu_deactivate_apicv() function to turn APICv
off.  The flag is initialized based on the module parameter and CPU
capability, and consulted whenever an APICv-specific action is
performed.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:21 +01:00
Andrey Smetanin
6308630bd3 kvm/x86: split ioapic-handled and EOI exit bitmaps
The function to determine if the vector is handled by ioapic used to
rely on the fact that only ioapic-handled vectors were set up to
cause vmexits when virtual apic was in use.

We're going to break this assumption when introducing Hyper-V
synthetic interrupts: they may need to cause vmexits too.

To achieve that, introduce a new bitmap dedicated specifically for
ioapic-handled vectors, and populate EOI exit bitmap from it for now.

Signed-off-by: Andrey Smetanin <asmetanin@virtuozzo.com>
Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Gleb Natapov <gleb@kernel.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Roman Kagan <rkagan@virtuozzo.com>
CC: Denis V. Lunev <den@openvz.org>
CC: qemu-devel@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-25 17:24:21 +01:00
Borislav Petkov
ae8b787543 x86/cpu/amd, kvm: Satisfy guest kernel reads of IC_CFG MSR
The kernel accesses IC_CFG MSR (0xc0011021) on AMD because it
checks whether the way access filter is enabled on some F15h
models, and, if so, disables it.

kvm doesn't handle that MSR access and complains about it, which
can get really noisy in dmesg when one starts kvm guests all the
time for testing. And it is useless anyway - guest kernel
shouldn't be doing such changes anyway so tell it that that
filter is disabled.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1448273546-2567-4-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-11-24 09:15:54 +01:00
Paolo Bonzini
a96036b8ef KVM: x86: rename update_db_bp_intercept to update_bp_intercept
Because #DB is now intercepted unconditionally, this callback
only operates on #BP for both VMX and SVM.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:25 +01:00
Paolo Bonzini
cbdb967af3 KVM: svm: unconditionally intercept #DB
This is needed to avoid the possibility that the guest triggers
an infinite stream of #DB exceptions (CVE-2015-8104).

VMX is not affected: because it does not save DR6 in the VMCS,
it already intercepts #DB unconditionally.

Reported-by: Jan Beulich <jbeulich@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:24 +01:00
Eric Northup
54a20552e1 KVM: x86: work around infinite loop in microcode when #AC is delivered
It was found that a guest can DoS a host by triggering an infinite
stream of "alignment check" (#AC) exceptions.  This causes the
microcode to enter an infinite loop where the core never receives
another interrupt.  The host kernel panics pretty quickly due to the
effects (CVE-2015-5307).

Signed-off-by: Eric Northup <digitaleric@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:24 +01:00
Haozhong Zhang
4ba76538dd KVM: x86: Move TSC scaling logic out of call-back read_l1_tsc()
Both VMX and SVM scales the host TSC in the same way in call-back
read_l1_tsc(), so this patch moves the scaling logic from call-back
read_l1_tsc() to a common function kvm_read_l1_tsc().

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:18 +01:00
Haozhong Zhang
58ea676787 KVM: x86: Move TSC scaling logic out of call-back adjust_tsc_offset()
For both VMX and SVM, if the 2nd argument of call-back
adjust_tsc_offset() is the host TSC, then adjust_tsc_offset() will scale
it first. This patch moves this common TSC scaling logic to its caller
adjust_tsc_offset_host() and rename the call-back adjust_tsc_offset() to
adjust_tsc_offset_guest().

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:17 +01:00
Haozhong Zhang
07c1419a32 KVM: x86: Replace call-back compute_tsc_offset() with a common function
Both VMX and SVM calculate the tsc-offset in the same way, so this
patch removes the call-back compute_tsc_offset() and replaces it with a
common function kvm_compute_tsc_offset().

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:16 +01:00
Haozhong Zhang
381d585c80 KVM: x86: Replace call-back set_tsc_khz() with a common function
Both VMX and SVM propagate virtual_tsc_khz in the same way, so this
patch removes the call-back set_tsc_khz() and replaces it with a common
function.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:16 +01:00
Haozhong Zhang
35181e86df KVM: x86: Add a common TSC scaling function
VMX and SVM calculate the TSC scaling ratio in a similar logic, so this
patch generalizes it to a common TSC scaling function.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
[Inline the multiplication and shift steps into mul_u64_u64_shr.  Remove
 BUG_ON.  - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:15 +01:00
Haozhong Zhang
ad721883e9 KVM: x86: Add a common TSC scaling ratio field in kvm_vcpu_arch
This patch moves the field of TSC scaling ratio from the architecture
struct vcpu_svm to the common struct kvm_vcpu_arch.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:14 +01:00
Haozhong Zhang
bc9b961b35 KVM: x86: Collect information for setting TSC scaling ratio
The number of bits of the fractional part of the 64-bit TSC scaling
ratio in VMX and SVM is different. This patch makes the architecture
code to collect the number of fractional bits and other related
information into variables that can be accessed in the common code.

Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-11-10 12:06:14 +01:00
Paolo Bonzini
5690891bce kvm: x86: zero EFER on INIT
Not zeroing EFER means that a 32-bit firmware cannot enter paging mode
without clearing EFER.LME first (which it should not know about).
Yang Zhang from Intel confirmed that the manual is wrong and EFER is
cleared to zero on INIT.

Fixes: d28bc9dd25
Cc: stable@vger.kernel.org
Cc: Yang Z Zhang <yang.z.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-19 11:34:45 +02:00
Joerg Roedel
6092d3d3e6 kvm: svm: Only propagate next_rip when guest supports it
Currently we always write the next_rip of the shadow vmcb to
the guests vmcb when we emulate a vmexit. This could confuse
the guest when its cpuid indicated no support for the
next_rip feature.

Fix this by only propagating next_rip if the guest actually
supports it.

Cc: Bandan Das <bsd@redhat.com>
Cc: Dirk Mueller <dmueller@suse.com>
Tested-By: Dirk Mueller <dmueller@suse.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-16 10:32:17 +02:00
Paolo Bonzini
4ca7dd8ce4 KVM: x86: unify handling of interrupt window
The interrupt window is currently checked twice, once in vmx.c/svm.c and
once in dm_request_for_irq_injection.  The only difference is the extra
check for kvm_arch_interrupt_allowed in dm_request_for_irq_injection,
and the different return value (EINTR/KVM_EXIT_INTR for vmx.c/svm.c vs.
0/KVM_EXIT_IRQ_WINDOW_OPEN for dm_request_for_irq_injection).

However, dm_request_for_irq_injection is basically dead code!  Revive it
by removing the checks in vmx.c and svm.c's vmexit handlers, and
fixing the returned values for the dm_request_for_irq_injection case.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 15:06:26 +02:00
Paolo Bonzini
35754c987f KVM: x86: introduce lapic_in_kernel
Avoid pointer chasing and memory barriers, and simplify the code
when split irqchip (LAPIC in kernel, IOAPIC/PIC in userspace)
is introduced.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 15:06:25 +02:00
Paolo Bonzini
d50ab6c1a2 KVM: x86: replace vm_has_apicv hook with cpu_uses_apicv
This will avoid an unnecessary trip to ->kvm and from there to the VPIC.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 15:06:24 +02:00
Paolo Bonzini
3bb345f387 KVM: x86: store IOAPIC-handled vectors in each VCPU
We can reuse the algorithm that computes the EOI exit bitmap to figure
out which vectors are handled by the IOAPIC.  The only difference
between the two is for edge-triggered interrupts other than IRQ8
that have no notifiers active; however, the IOAPIC does not have to
do anything special for these interrupts anyway.

This again limits the interactions between the IOAPIC and the LAPIC,
making it easier to move the former to userspace.

Inspired by a patch from Steve Rutherford.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 15:06:23 +02:00
Dirk Müller
d2922422c4 Use WARN_ON_ONCE for missing X86_FEATURE_NRIPS
The cpu feature flags are not ever going to change, so warning
everytime can cause a lot of kernel log spam
(in our case more than 10GB/hour).

The warning seems to only occur when nested virtualization is
enabled, so it's probably triggered by a KVM bug.  This is a
sensible and safe change anyway, and the KVM bug fix might not
be suitable for stable releases anyway.

Cc: stable@vger.kernel.org
Signed-off-by: Dirk Mueller <dmueller@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 14:59:37 +02:00
Paolo Bonzini
fc07e76ac7 Revert "KVM: SVM: use NPT page attributes"
This reverts commit 3c2e7f7de3.
Initializing the mapping from MTRR to PAT values was reported to
fail nondeterministically, and it also caused extremely slow boot
(due to caching getting disabled---bug 103321) with assigned devices.

Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Reported-by: Sebastian Schuette <dracon@ewetel.net>
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 13:30:44 +02:00
Paolo Bonzini
bcf166a994 Revert "KVM: svm: handle KVM_X86_QUIRK_CD_NW_CLEARED in svm_get_mt_mask"
This reverts commit 5492830370.
It builds on the commit that is being reverted next.

Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 13:30:43 +02:00
Paolo Bonzini
625422f60c Revert "KVM: SVM: Sync g_pat with guest-written PAT value"
This reverts commit e098223b78,
which has a dependency on other commits being reverted.

Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 13:30:43 +02:00
Paolo Bonzini
606decd670 Revert "KVM: x86: apply guest MTRR virtualization on host reserved pages"
This reverts commit fd717f1101.
It was reported to cause Machine Check Exceptions (bug 104091).

Reported-by: harn-solo@gmx.de
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-10-01 13:30:42 +02:00
Paolo Bonzini
79a8059d24 KVM: svm: do not call kvm_set_cr0 from init_vmcb
kvm_set_cr0 may want to call kvm_zap_gfn_range and thus access the
memslots array (SRCU protected).  Using a mini SRCU critical section
is ugly, and adding it to kvm_arch_vcpu_create doesn't work because
the VMX vcpu_create callback calls synchronize_srcu.

Fixes this lockdep splat:

===============================
[ INFO: suspicious RCU usage. ]
4.3.0-rc1+ #1 Not tainted
-------------------------------
include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage!

other info that might help us debug this:
rcu_scheduler_active = 1, debug_locks = 0
1 lock held by qemu-system-i38/17000:
 #0:  (&(&kvm->mmu_lock)->rlock){+.+...}, at: kvm_zap_gfn_range+0x24/0x1a0 [kvm]

[...]
Call Trace:
 dump_stack+0x4e/0x84
 lockdep_rcu_suspicious+0xfd/0x130
 kvm_zap_gfn_range+0x188/0x1a0 [kvm]
 kvm_set_cr0+0xde/0x1e0 [kvm]
 init_vmcb+0x760/0xad0 [kvm_amd]
 svm_create_vcpu+0x197/0x250 [kvm_amd]
 kvm_arch_vcpu_create+0x47/0x70 [kvm]
 kvm_vm_ioctl+0x302/0x7e0 [kvm]
 ? __lock_is_held+0x51/0x70
 ? __fget+0x101/0x210
 do_vfs_ioctl+0x2f4/0x560
 ? __fget_light+0x29/0x90
 SyS_ioctl+0x4c/0x90
 entry_SYSCALL_64_fastpath+0x16/0x73

Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-25 10:31:22 +02:00
Igor Mammedov
ebae871a50 kvm: svm: reset mmu on VCPU reset
When INIT/SIPI sequence is sent to VCPU which before that
was in use by OS, VMRUN might fail with:

 KVM: entry failed, hardware error 0xffffffff
 EAX=00000000 EBX=00000000 ECX=00000000 EDX=000006d3
 ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000
 EIP=00000000 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0
 ES =0000 00000000 0000ffff 00009300
 CS =9a00 0009a000 0000ffff 00009a00
 [...]
 CR0=60000010 CR2=b6f3e000 CR3=01942000 CR4=000007e0
 [...]
 EFER=0000000000000000

with corresponding SVM error:
 KVM: FAILED VMRUN WITH VMCB:
 [...]
 cpl:            0                efer:         0000000000001000
 cr0:            0000000080010010 cr2:          00007fd7fe85bf90
 cr3:            0000000187d0c000 cr4:          0000000000000020
 [...]

What happens is that VCPU state right after offlinig:
CR0: 0x80050033  EFER: 0xd01  CR4: 0x7e0
  -> long mode with CR3 pointing to longmode page tables

and when VCPU gets INIT/SIPI following transition happens
CR0: 0 -> 0x60000010 EFER: 0x0  CR4: 0x7e0
  -> paging disabled with stale CR3

However SVM under the hood puts VCPU in Paged Real Mode*
which effectively translates CR0 0x60000010 -> 80010010 after

   svm_vcpu_reset()
       -> init_vmcb()
           -> kvm_set_cr0()
               -> svm_set_cr0()

but from  kvm_set_cr0() perspective CR0: 0 -> 0x60000010
only caching bits are changed and
commit d81135a57a
 ("KVM: x86: do not reset mmu if CR0.CD and CR0.NW are changed")'
regressed svm_vcpu_reset() which relied on MMU being reset.

As result VMRUN after svm_vcpu_reset() tries to run
VCPU in Paged Real Mode with stale MMU context (longmode page tables),
which causes some AMD CPUs** to bail out with VMEXIT_INVALID.

Fix issue by unconditionally resetting MMU context
at init_vmcb() time.

	* AMD64 Architecture Programmer’s Manual,
	    Volume 2: System Programming, rev: 3.25
	      15.19 Paged Real Mode
	** Opteron 1216

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Fixes: d81135a57a
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-09-18 16:49:02 +02:00
Linus Torvalds
5778077d03 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm changes from Ingo Molnar:
 "The biggest changes in this cycle were:

   - Revamp, simplify (and in some cases fix) Time Stamp Counter (TSC)
     primitives.  (Andy Lutomirski)

   - Add new, comprehensible entry and exit handlers written in C.
     (Andy Lutomirski)

   - vm86 mode cleanups and fixes.  (Brian Gerst)

   - 32-bit compat code cleanups.  (Brian Gerst)

  The amount of simplification in low level assembly code is already
  palpable:

     arch/x86/entry/entry_32.S                          | 130 +----
     arch/x86/entry/entry_64.S                          | 197 ++-----

  but more simplifications are planned.

  There's also the usual laudry mix of low level changes - see the
  changelog for details"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (83 commits)
  x86/asm: Drop repeated macro of X86_EFLAGS_AC definition
  x86/asm/msr: Make wrmsrl() a function
  x86/asm/delay: Introduce an MWAITX-based delay with a configurable timer
  x86/asm: Add MONITORX/MWAITX instruction support
  x86/traps: Weaken context tracking entry assertions
  x86/asm/tsc: Add rdtscll() merge helper
  selftests/x86: Add syscall_nt selftest
  selftests/x86: Disable sigreturn_64
  x86/vdso: Emit a GNU hash
  x86/entry: Remove do_notify_resume(), syscall_trace_leave(), and their TIF masks
  x86/entry/32: Migrate to C exit path
  x86/entry/32: Remove 32-bit syscall audit optimizations
  x86/vm86: Rename vm86->v86flags and v86mask
  x86/vm86: Rename vm86->vm86_info to user_vm86
  x86/vm86: Clean up vm86.h includes
  x86/vm86: Move the vm86 IRQ definitions to vm86.h
  x86/vm86: Use the normal pt_regs area for vm86
  x86/vm86: Eliminate 'struct kernel_vm86_struct'
  x86/vm86: Move fields from 'struct kernel_vm86_struct' to 'struct vm86'
  x86/vm86: Move vm86 fields out of 'thread_struct'
  ...
2015-09-01 08:40:25 -07:00
Xiao Guangrong
c258b62b26 KVM: MMU: introduce the framework to check zero bits on sptes
We have abstracted the data struct and functions which are used to check
reserved bit on guest page tables, now we extend the logic to check
zero bits on shadow page tables

The zero bits on sptes include not only reserved bits on hardware but also
the bits that SPTEs willnever use.  For example, shadow pages will never
use GB pages unless the guest uses them too.

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-08-05 12:47:24 +02:00
Ingo Molnar
5b929bd11d Merge branch 'x86/urgent' into x86/asm, before applying dependent patches
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-31 10:23:35 +02:00
Paolo Bonzini
5492830370 KVM: svm: handle KVM_X86_QUIRK_CD_NW_CLEARED in svm_get_mt_mask
We can disable CD unconditionally when there is no assigned device.
KVM now forces guest PAT to all-writeback in that case, so it makes
sense to also force CR0.CD=0.

When there are assigned devices, emulate cache-disabled operation
through the page tables.  This behavior is consistent with VMX
microcode, where CD/NW are not touched by vmentry/vmexit.  However,
keep this dependent on the quirk because OVMF enables the caches
too late.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23 08:30:27 +02:00
Paolo Bonzini
0da029ed7e KVM: x86: rename quirk constants to KVM_X86_QUIRK_*
Make them clearly architecture-dependent; the capability is valid for
all architectures, but the argument is not.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-07-23 08:24:42 +02:00