Avi Kivity [Sun, 2 Dec 2007 08:50:06 +0000 (10:50 +0200)]
KVM: Export include/linux/kvm.h only if $ARCH actually supports KVM
Currently, make headers_check barfs due to <asm/kvm.h>, which <linux/kvm.h>
includes, not existing. Rather than add a zillion <asm/kvm.h>s, export kvm.h
only if the arch actually supports it.
Avi Kivity [Tue, 27 Nov 2007 17:30:56 +0000 (19:30 +0200)]
KVM: x86 emulator: unify four switch statements into two
Unify the special instruction switch with the regular instruction switch,
and the two byte special instruction switch with the regular two byte
instruction switch. That makes it much easier to find an instruction or
the place an instruction needs to be added in.
Jerone Young [Mon, 26 Nov 2007 14:33:53 +0000 (08:33 -0600)]
KVM: Add ifdef in irqchip struct for x86 only structures
This patch fixes a small issue where sturctures:
kvm_pic_state
kvm_ioapic_state
are defined inside x86 specific code and may or may not
be defined in anyway for other architectures. The problem
caused is one cannot compile userspace apps (ex. libkvm)
for other archs since a size cannot be determined for these
structures.
Signed-off-by: Jerone Young <jyoung5@us.ibm.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
KVM: x86 emulator: Make a distinction between repeat prefixes F3 and F2
cmps and scas instructions accept repeat prefixes F3 and F2. So in
order to emulate those prefixed instructions we need to be able to know
if prefixes are REP/REPE/REPZ or REPNE/REPNZ. Currently kvm doesn't make
this distinction. This patch introduces this distinction.
Signed-off-by: Guillaume Thouvenin <guillaume.thouvenin@ext.bull.net> Signed-off-by: Avi Kivity <avi@qumranet.com>
Dan Kenigsberg [Wed, 21 Nov 2007 15:10:04 +0000 (17:10 +0200)]
KVM: Enhance guest cpuid management
The current cpuid management suffers from several problems, which inhibit
passing through the host feature set to the guest:
- No way to tell which features the host supports
While some features can be supported with no changes to kvm, others
need explicit support. That means kvm needs to vet the feature set
before it is passed to the guest.
- No support for indexed or stateful cpuid entries
Some cpuid entries depend on ecx as well as on eax, or on internal
state in the processor (running cpuid multiple times with the same
input returns different output). The current cpuid machinery only
supports keying on eax.
- No support for save/restore/migrate
The internal state above needs to be exposed to userspace so it can
be saved or migrated.
This patch adds extended cpuid support by means of three new ioctls:
- KVM_GET_SUPPORTED_CPUID: get all cpuid entries the host (and kvm)
supports
- KVM_SET_CPUID2: sets the vcpu's cpuid table
- KVM_GET_CPUID2: gets the vcpu's cpuid table, including hidden state
[avi: fix original KVM_SET_CPUID not removing nx on non-nx hosts as it did
before]
Signed-off-by: Dan Kenigsberg <danken@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Avi Kivity [Wed, 21 Nov 2007 13:28:32 +0000 (15:28 +0200)]
KVM: MMU: Rename variables of type 'struct kvm_mmu_page *'
These are traditionally named 'page', but even more traditionally, that name
is reserved for variables that point to a 'struct page'. Rename them to 'sp'
(for "shadow page").
Avi Kivity [Wed, 21 Nov 2007 12:44:45 +0000 (14:44 +0200)]
KVM: MMU: Introduce gfn_to_gpa()
Converting a frame number to an address is tricky since the data type changes
size. Introduce a function to do it. This fixes an actual bug when
accessing guest ptes.
Avi Kivity [Wed, 21 Nov 2007 00:06:21 +0000 (02:06 +0200)]
KVM: MMU: Avoid unnecessary remote tlb flushes when guest updates a pte
If all we're doing is increasing permissions on a pte (typical for demand
paging), then there's not need to flush remote tlbs. Worst case they'll
get a spurious page fault.
Avi Kivity [Tue, 20 Nov 2007 19:39:54 +0000 (21:39 +0200)]
KVM: MMU: Implement guest page fault bypass for nonpae
I spent an hour worrying why I see so many guest page faults on FC6 i386.
Turns out bypass wasn't implemented for nonpae. Implement it so it doesn't
happen again.
Avi Kivity [Tue, 20 Nov 2007 13:30:24 +0000 (15:30 +0200)]
KVM: Split vcpu creation to avoid vcpu_load() before preemption setup
Split kvm_arch_vcpu_create() into kvm_arch_vcpu_create() and
kvm_arch_vcpu_setup(), enabling preemption notification between the two.
This mean that we can now do vcpu_load() within kvm_arch_vcpu_setup().
Avi Kivity [Tue, 20 Nov 2007 10:49:31 +0000 (12:49 +0200)]
KVM: x86 emulator: retire ->write_std()
Theoretically used to acccess memory known to be ordinary RAM, it was
never implemented. It is questionable whether it is possible to implement
it correctly.
Izik Eidus [Tue, 20 Nov 2007 09:49:33 +0000 (11:49 +0200)]
KVM: MMU: Selectively set PageDirty when releasing guest memory
Improve dirty bit setting for pages that kvm release, until now every page
that we released we marked dirty, from now only pages that have potential
to get dirty we mark dirty.
Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Izik Eidus [Tue, 20 Nov 2007 09:30:04 +0000 (11:30 +0200)]
KVM: MMU: Fix potential memory leak with smp real-mode
When we map a page, we check whether some other vcpu mapped it for us and if
so, bail out. But we should decrease the refcount on the page as we do so.
Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Jan Kiszka [Mon, 19 Nov 2007 09:21:45 +0000 (10:21 +0100)]
KVM: VMX: Force seg.base == (seg.sel << 4) in real mode
Ensure that segment.base == segment.selector << 4 when entering the real
mode on Intel so that the CPU will not bark at us. This fixes some old
protected mode demo from http://www.x86.org/articles/pmbasics/tspec_a1_doc.htm.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Avi Kivity [Sun, 18 Nov 2007 11:50:24 +0000 (13:50 +0200)]
KVM: Replace 'light_exits' stat with 'host_state_reload'
This is a little more accurate (since it counts actual reloads, not potential
reloads), and reverses the sense of the statistic to measure a bad event like
most of the other stats (e.g. we want to minimize all counters).
Avi Kivity [Thu, 15 Nov 2007 16:06:18 +0000 (18:06 +0200)]
KVM: VMX: Consolidate register usage in vmx_vcpu_run()
We pass vcpu, vmx->fail, and vmx->launched to assembly code, but all three
are fields within vmx. Consolidate by only passing in vmx and offsets for
the rest.
Izik Eidus [Sun, 11 Nov 2007 20:10:22 +0000 (22:10 +0200)]
KVM: Change kvm_{read,write}_guest() to use copy_{from,to}_user()
This changes kvm_write_guest_page/kvm_read_guest_page to use
copy_to_user/read_from_user, as a result we get better speed
and better dirty bit tracking.
Signed-off-by: Izik Eidus <izike@qumranet.com> Signed-off-by: Avi Kivity <avi@qumranet.com>
Avi Kivity [Thu, 22 Nov 2007 09:42:59 +0000 (11:42 +0200)]
KVM: Fix faults during injection of real-mode interrupts
If vmx fails to inject a real-mode interrupt while fetching the interrupt
redirection table, it fails to record this in the vectoring information
field. So we detect this condition and do it ourselves.
Avi Kivity [Thu, 8 Nov 2007 16:19:20 +0000 (18:19 +0200)]
KVM: VMX: Use vmx to inject real-mode interrupts
Instead of injecting real-mode interrupts by writing the interrupt frame into
guest memory, abuse vmx by injecting a software interrupt. We need to
pretend the software interrupt instruction had a length > 0, so we have to
adjust rip backward.
This lets us not to mess with writing guest memory, which is complex and also
sleeps.
Avi Kivity [Wed, 31 Oct 2007 09:15:56 +0000 (11:15 +0200)]
KVM: x86 emulator: centralize decoding of one-byte register access insns
Instructions like 'inc reg' that have the register operand encoded
in the opcode are currently specially decoded. Extend
decode_register_operand() to handle that case, indicated by having
DstReg or SrcReg without ModRM.