Commit Graph

7 Commits

Author SHA1 Message Date
Tom Lendacky
1958b5fc40 x86/boot: Add early boot support when running with SEV active
Early in the boot process, add checks to determine if the kernel is
running with Secure Encrypted Virtualization (SEV) active.

Checking for SEV requires checking that the kernel is running under a
hypervisor (CPUID 0x00000001, bit 31), that the SEV feature is available
(CPUID 0x8000001f, bit 1) and then checking a non-interceptable SEV MSR
(0xc0010131, bit 0).

This check is required so that during early compressed kernel booting the
pagetables (both the boot pagetables and KASLR pagetables (if enabled) are
updated to include the encryption mask so that when the kernel is
decompressed into encrypted memory, it can boot properly.

After the kernel is decompressed and continues booting the same logic is
used to check if SEV is active and set a flag indicating so.  This allows
to distinguish between SME and SEV, each of which have unique differences
in how certain things are handled: e.g. DMA (always bounce buffered with
SEV) or EFI tables (always access decrypted with SME).

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Borislav Petkov <bp@suse.de>
Tested-by: Borislav Petkov <bp@suse.de>
Cc: Laura Abbott <labbott@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kvm@vger.kernel.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20171020143059.3291-13-brijesh.singh@amd.com
2017-11-07 15:35:58 +01:00
Greg Kroah-Hartman
6f52b16c5b License cleanup: add SPDX license identifier to uapi header files with no license
Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.

By default are files without license information under the default
license of the kernel, which is GPLV2.  Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:

   NOTE! This copyright does *not* cover user programs that use kernel
   services by normal system calls - this is merely considered normal use
   of the kernel, and does *not* fall under the heading of "derived work".

otherwise syscall usage would not be possible.

Update the files which contain no license information with an SPDX
license identifier.  The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception.  SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.  See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:19:54 +01:00
Wanpeng Li
52a5c155cf KVM: async_pf: Let guest support delivery of async_pf from guest mode
Adds another flag bit (bit 2) to MSR_KVM_ASYNC_PF_EN. If bit 2 is 1,
async page faults are delivered to L1 as #PF vmexits; if bit 2 is 0,
kvm_can_do_async_pf returns 0 if in guest mode.

This is similar to what svm.c wanted to do all along, but it is only
enabled for Linux as L1 hypervisor.  Foreign hypervisors must never
receive async page faults as vmexits, because they'd probably be very
confused about that.

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
Marcelo Tosatti
55dd00a73a KVM: x86: add KVM_HC_CLOCK_PAIRING hypercall
Add a hypercall to retrieve the host realtime clock and the TSC value
used to calculate that clock read.

Used to implement clock synchronization between host and guest.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-02-07 18:16:45 +01:00
Pan Xinhui
0b9f6c4615 x86/kvm: Support the vCPU preemption check
Support the vcpu_is_preempted() functionality under KVM. This will
enhance lock performance on overcommitted hosts (more runnable vCPUs
than physical CPUs in the system) as doing busy waits for preempted
vCPUs will hurt system performance far worse than early yielding.

Use struct kvm_steal_time::preempted to indicate that if a vCPU
is running or not.

Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: David.Laight@ACULAB.COM
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: benh@kernel.crashing.org
Cc: boqun.feng@gmail.com
Cc: borntraeger@de.ibm.com
Cc: bsingharora@gmail.com
Cc: dave@stgolabs.net
Cc: jgross@suse.com
Cc: kernellwp@gmail.com
Cc: konrad.wilk@oracle.com
Cc: linuxppc-dev@lists.ozlabs.org
Cc: mpe@ellerman.id.au
Cc: paulmck@linux.vnet.ibm.com
Cc: paulus@samba.org
Cc: rkrcmar@redhat.com
Cc: virtualization@lists.linux-foundation.org
Cc: will.deacon@arm.com
Cc: xen-devel-request@lists.xenproject.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1478077718-37424-9-git-send-email-xinhui.pan@linux.vnet.ibm.com
[ Typo fixes. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:48:08 +01:00
Raghavendra K T
3a3bb00d5c kvm uapi: Add KICK_CPU and PV_UNHALT definition to uapi
These are needed by both guest and host.

Originally-from: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1376058122-8248-13-git-send-email-raghavendra.kt@linux.vnet.ibm.com
Acked-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-08-09 07:54:12 -07:00
David Howells
af170c5061 UAPI: (Scripted) Disintegrate arch/x86/include/asm
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>
2012-12-14 22:37:13 +00:00