提交 · 7cc8883074b040aa8c1ebd3a17463b0ea3a9ef16 · openanolis / cloud-kernel

20 7月, 2008 16 次提交

A
KVM: Remove decache_vcpus_on_cpu() and related callbacks · 7cc88830
由 Avi Kivity 提交于 5月 13, 2008
```
Obsoleted by the vmx-specific per-cpu list.
Signed-off-by: NAvi Kivity <avi@qumranet.com>
```
7cc88830

KVM: VMX: Add list of potentially locally cached vcpus · 543e4243

由 Avi Kivity 提交于 5月 13, 2008

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: NAndrea Arcangeli <andrea@qumranet.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

543e4243

KVM: Handle virtualization instruction #UD faults during reboot · 4ecac3fd

由 Avi Kivity 提交于 5月 13, 2008

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: NAvi Kivity <avi@qumranet.com>

4ecac3fd

KVM: MMU: Fix false flooding when a pte points to page table · 1b7fcd32

由 Avi Kivity 提交于 5月 15, 2008

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: NAvi Kivity <avi@qumranet.com>

1b7fcd32

A
KVM: VMX: Trivial vmcs_write64() code simplification · 7682f2d0
由 Avi Kivity 提交于 5月 12, 2008
```
Signed-off-by: NAvi Kivity <avi@qumranet.com>
```
7682f2d0

KVM: SVM: Fake MSR_K7 performance counters · 14ae51b6

由 Chris Lalancette 提交于 5月 05, 2008

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: NChris Lalancette <clalance@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

14ae51b6

KVM: PIT: support mode 3 · f6975545

由 Aurelien Jarno 提交于 5月 02, 2008

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: NAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

f6975545

KVM: Handle vma regions with no backing page · 2e2e3738

由 Anthony Liguori 提交于 4月 30, 2008

This patch allows VMAs that contain no backing page to be used for guest
memory.  This is useful for assigning mmio regions to a guest.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

2e2e3738

KVM: SVM: add tracing support for TDP page faults · d2ebb410