Instead of prefetching all segment bases before emulation, read them at the
last moment. Since most of them are unneeded, we save some cycles on
Intel machines where this is a bit expensive.
Signed-off-by: Avi Kivity <avi@qumranet.com>
rip relative decoding is relative to the instruction pointer of the next
instruction; by moving address adjustment until after decoding is complete,
we remove the need to determine the instruction size.
Signed-off-by: Avi Kivity <avi@qumranet.com>
If we're not gonna do anything (case in which failure is already
reported), we do not need to even bother with calculating the linear rip.
Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Only abort guest entry if the timer count went from 0->1, since for 1->2
or larger the bit will either be set already or a timer irq will have
been injected.
Using atomic_inc_and_test() for it also introduces an SMP barrier
to the LAPIC version (thought it was unecessary because of timer
migration, but guest can be scheduled to a different pCPU between exit
and kvm_vcpu_block(), so there is the possibility for a race).
Noticed by Avi.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch enables coalesced MMIO for x86 architecture.
It defines KVM_MMIO_PAGE_OFFSET and KVM_CAP_COALESCED_MMIO.
It enables the compilation of coalesced_mmio.c.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Modify member in_range() of structure kvm_io_device to pass length and the type
of the I/O (write or read).
This modification allows to use kvm_io_device with coalesced MMIO.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
SVM cannot benefit from page prefetching since guest page fault bypass
cannot by made to work there. Avoid accessing the guest page table in
this case.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Encountered in FC6 boot sequence, now that we don't force ss.rpl = 0 during
the protected mode transition. Not really necessary, but nice to have.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Add support for mov r, sreg (0x8c) instruction.
[avi: drop the sreg decoding table in favor of 1:1 encoding]
Signed-off-by: Guillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: Laurent Vivier <laurent.vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Add support for jmp far (opcode 0xea) instruction.
Signed-off-by: Guillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: Laurent Vivier <laurent.vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Update c->dst.bytes in decode instruction instead of instruction
itself. It's needed because if c->dst.bytes is equal to 0, the
instruction is not emulated.
Signed-off-by: Guillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: Laurent Vivier <laurent.vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Prefixes functions that will be exported with kvm_.
We also prefixed set_segment() even if it still static
to be coherent.
signed-off-by: Guillaume Thouvenin <guillaume.thouvenin@ext.bull.net>
Signed-off-by: Laurent Vivier <laurent.vivier@bull.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Add emulation for the memory type range registers, needed by VMware esx 3.5,
and by pci device assignment.
Signed-off-by: Avi Kivity <avi@qumranet.com>
VMX hardware can cache the contents of a vcpu's vmcs. This cache needs
to be flushed when migrating a vcpu to another cpu, or (which is the case
that interests us here) when disabling hardware virtualization on a cpu.
The current implementation of decaching iterates over the list of all vcpus,
picks the ones that are potentially cached on the cpu that is being offlined,
and flushes the cache. The problem is that it uses mutex_trylock() to gain
exclusive access to the vcpu, which fires off a (benign) warning about using
the mutex in an interrupt context.
To avoid this, and to make things generally nicer, add a new per-cpu list
of potentially cached vcus. This makes the decaching code much simpler. The
list is vmx-specific since other hardware doesn't have this issue.
[andrea: fix crash on suspend/resume]
Signed-off-by: Andrea Arcangeli <andrea@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
KVM turns off hardware virtualization extensions during reboot, in order
to disassociate the memory used by the virtualization extensions from the
processor, and in order to have the system in a consistent state.
Unfortunately virtual machines may still be running while this goes on,
and once virtualization extensions are turned off, any virtulization
instruction will #UD on execution.
Fix by adding an exception handler to virtualization instructions; if we get
an exception during reboot, we simply spin waiting for the reset to complete.
If it's a true exception, BUG() so we can have our stack trace.
Signed-off-by: Avi Kivity <avi@qumranet.com>
The KVM MMU tries to detect when a speculative pte update is not actually
used by demand fault, by checking the accessed bit of the shadow pte. If
the shadow pte has not been accessed, we deem that page table flooded and
remove the shadow page table, allowing further pte updates to proceed
without emulation.
However, if the pte itself points at a page table and only used for write
operations, the accessed bit will never be set since all access will happen
through the emulator.
This is exactly what happens with kscand on old (2.4.x) HIGHMEM kernels.
The kernel points a kmap_atomic() pte at a page table, and then
proceeds with read-modify-write operations to look at the dirty and accessed
bits. We get a false flood trigger on the kmap ptes, which results in the
mmu spending all its time setting up and tearing down shadows.
Fix by setting the shadow accessed bit on emulated accesses.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Attached is a patch that fixes a guest crash when booting older Linux kernels.
The problem stems from the fact that we are currently emulating
MSR_K7_EVNTSEL[0-3], but not emulating MSR_K7_PERFCTR[0-3]. Because of this,
setup_k7_watchdog() in the Linux kernel receives a GPF when it attempts to
write into MSR_K7_PERFCTR, which causes an OOPs.
The patch fixes it by just "fake" emulating the appropriate MSRs, throwing
away the data in the process. This causes the NMI watchdog to not actually
work, but it's not such a big deal in a virtualized environment.
When we get a write to one of these counters, we printk_ratelimit() a warning.
I decided to print it out for all writes, even if the data is 0; it doesn't
seem to make sense to me to special case when data == 0.
Tested by myself on a RHEL-4 guest, and Joerg Roedel on a Windows XP 64-bit
guest.
Signed-off-by: Chris Lalancette <clalance@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
The in-kernel PIT emulation ignores pending timers if operating
under mode 3, which for example Hurd uses.
This mode should output a square wave, high for (N+1)/2 counts and low
for (N-1)/2 counts. As we only care about the resulting interrupts, the
period is N, and mode 3 is the same as mode 2 with regard to
interrupts.
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Avi Kivity <avi@qumranet.com>
To distinguish between real page faults and nested page faults they should be
traced as different events. This is implemented by this patch.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch adds the missing kvmtrace markers to the svm
module of kvm.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch adds some kvmtrace bits to the generic x86 code
where it is instrumented from SVM.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
With an exit handler for INTR intercepts its possible to account them using
kvmtrace.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
With an exit handler for NMI intercepts its possible to account them using
kvmtrace.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
This patch moves the trace entry for APIC accesses from the VMX code to the
generic lapic code. This way APIC accesses from SVM will also be traced.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Noticed by sparse:
arch/x86/kvm/vmx.c:1583:6: warning: symbol 'vmx_disable_intercept_for_msr' was not declared. Should it be static?
arch/x86/kvm/x86.c:3406:5: warning: symbol 'kvm_task_switch_16' was not declared. Should it be static?
arch/x86/kvm/x86.c:3429:5: warning: symbol 'kvm_task_switch_32' was not declared. Should it be static?
arch/x86/kvm/mmu.c:1968:6: warning: symbol 'kvm_mmu_remove_one_alloc_mmu_page' was not declared. Should it be static?
arch/x86/kvm/mmu.c:2014:6: warning: symbol 'mmu_destroy_caches' was not declared. Should it be static?
arch/x86/kvm/lapic.c:862:5: warning: symbol 'kvm_lapic_get_base' was not declared. Should it be static?
arch/x86/kvm/i8254.c:94:5: warning: symbol 'pit_get_gate' was not declared. Should it be static?
arch/x86/kvm/i8254.c:196:5: warning: symbol '__pit_timer_fn' was not declared. Should it be static?
arch/x86/kvm/i8254.c:561:6: warning: symbol '__inject_pit_timer_intr' was not declared. Should it be static?
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: fix asm/e820.h for userspace inclusion
x86: fix numaq_tsc_disable
x86: fix kernel_physical_mapping_init() for large x86 systems
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
ftrace: do not trace library functions
ftrace: do not trace scheduler functions
ftrace: fix lockup with MAXSMP
ftrace: fix merge buglet
fix:
arch/x86/kernel/numaq_32.c: In function ‘numaq_tsc_disable’:
arch/x86/kernel/numaq_32.c:99: warning: ‘return’ with a value, in function returning void
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
-tip testing found a bootup hang here:
initcall anon_inode_init+0x0/0x130 returned 0 after 0 msecs
calling acpi_event_init+0x0/0x57
the bootup should have continued with:
initcall acpi_event_init+0x0/0x57 returned 0 after 45 msecs
but it hung hard there instead.
bisection led to this commit:
| commit 5806b81ac1
| Merge: d14c8a6... 6712e29...
| Author: Ingo Molnar <mingo@elte.hu>
| Date: Mon Jul 14 16:11:52 2008 +0200
| Merge branch 'auto-ftrace-next' into tracing/for-linus
turns out that i made this mistake in the merge:
ifdef CONFIG_FTRACE
# Do not profile debug utilities
CFLAGS_REMOVE_tsc_64.o = -pg
CFLAGS_REMOVE_tsc_32.o = -pg
those two files got unified meanwhile - so the dont-profile annotation
got lost. The proper rule is:
CFLAGS_REMOVE_tsc.o = -pg
i guess this could have been caught sooner if the CFLAGS_REMOVE* kbuild
rule aborted the build if it met a target that does not exist anymore?
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (72 commits)
Revert "x86/PCI: ACPI based PCI gap calculation"
PCI: remove unnecessary volatile in PCIe hotplug struct controller
x86/PCI: ACPI based PCI gap calculation
PCI: include linux/pm_wakeup.h for device_set_wakeup_capable
PCI PM: Fix pci_prepare_to_sleep
x86/PCI: Fix PCI config space for domains > 0
Fix acpi_pm_device_sleep_wake() by providing a stub for CONFIG_PM_SLEEP=n
PCI: Simplify PCI device PM code
PCI PM: Introduce pci_prepare_to_sleep and pci_back_from_sleep
PCI ACPI: Rework PCI handling of wake-up
ACPI: Introduce new device wakeup flag 'prepared'
ACPI: Introduce acpi_device_sleep_wake function
PCI: rework pci_set_power_state function to call platform first
PCI: Introduce platform_pci_power_manageable function
ACPI: Introduce acpi_bus_power_manageable function
PCI: make pci_name use dev_name
PCI: handle pci_name() being const
PCI: add stub for pci_set_consistent_dma_mask()
PCI: remove unused arch pcibios_update_resource() functions
PCI: fix pci_setup_device()'s sprinting into a const buffer
...
Fixed up conflicts in various files (arch/x86/kernel/setup_64.c,
arch/x86/pci/irq.c, arch/x86/pci/pci.h, drivers/acpi/sleep/main.c,
drivers/pci/pci.c, drivers/pci/pci.h, include/acpi/acpi_bus.h) from x86
and ACPI updates manually.
"idle=nomwait" disables the use of the MWAIT
instruction from both C1 (C1_FFH) and deeper (C2C3_FFH)
C-states.
When MWAIT is unavailable, the BIOS and OS generally
negotiate to use the HALT instruction for C1,
and use IO accesses for deeper C-states.
This option is useful for power and performance
comparisons, and also to work around BIOS bugs
where broken MWAIT support is advertised.
http://bugzilla.kernel.org/show_bug.cgi?id=10807http://bugzilla.kernel.org/show_bug.cgi?id=10914
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Li Shaohua <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Avi Kivity
Mohammed Gamal
Glauber Costa
Marcelo Tosatti
Laurent Vivier
Guillaume Thouvenin
Sheng Yang
Chris Lalancette
Aurelien Jarno
Joerg Roedel
Harvey Harrison
Linus Torvalds
Yinghai Lu
Ingo Molnar
Jesse Barnes
Zhao Yakui