linux-toradex.git/arch/x86/kernel/kvm.c, branch v3.4.94

KVM: Do not take reference to mm during async #PF

2012-05-06T12:00:02+00:00

It turned to be totally unneeded. The reason the code was introduced is
so that KVM can prefault swapped in page, but prefault can fail even
if mm is pinned since page table can change anyway. KVM handles this
situation correctly though and does not inject spurious page faults.

Fixes:
 "INFO: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected" warning while
 running LTP inside a KVM guest using the recent -next kernel.

Reported-by: Sasha Levin 
Signed-off-by: Gleb Natapov 
Signed-off-by: Avi Kivity

KVM: Resolve RCU vs. async page fault problem

2012-04-05T16:26:14+00:00

"Page ready" async PF can kick vcpu out of idle state much like IRQ.
We need to tell RCU about this.

Reported-by: Sasha Levin 
Signed-off-by: Gleb Natapov 
Reviewed-by: Paul E. McKenney 
Signed-off-by: Avi Kivity

static keys: Introduce 'struct static_key', static_key_true()/false() and static_key_slow_[inc|dec]()

2012-02-24T09:05:59+00:00

So here's a boot tested patch on top of Jason's series that does
all the cleanups I talked about and turns jump labels into a
more intuitive to use facility. It should also address the
various misconceptions and confusions that surround jump labels.

Typical usage scenarios:

        #include 

        struct static_key key = STATIC_KEY_INIT_TRUE;

        if (static_key_false(&key))
                do unlikely code
        else
                do likely code

Or:

        if (static_key_true(&key))
                do likely code
        else
                do unlikely code

The static key is modified via:

        static_key_slow_inc(&key);
        ...
        static_key_slow_dec(&key);

The 'slow' prefix makes it abundantly clear that this is an
expensive operation.

I've updated all in-kernel code to use this everywhere. Note
that I (intentionally) have not pushed through the rename
blindly through to the lowest levels: the actual jump-label
patching arch facility should be named like that, so we want to
decouple jump labels from the static-key facility a bit.

On non-jump-label enabled architectures static keys default to
likely()/unlikely() branches.

Signed-off-by: Ingo Molnar 
Acked-by: Jason Baron 
Acked-by: Steven Rostedt 
Cc: a.p.zijlstra@chello.nl
Cc: mathieu.desnoyers@efficios.com
Cc: davem@davemloft.net
Cc: ddaney.cavm@gmail.com
Cc: Linus Torvalds 
Link: http://lkml.kernel.org/r/20120222085809.GA26397@elte.hu
Signed-off-by: Ingo Molnar

KVM guest: remove KVM guest pv mmu support

2011-12-27T09:17:08+00:00

This has not been used for some years now.  It's time to remove it.

Signed-off-by: Chris Wright 
Signed-off-by: Avi Kivity

KVM guest: KVM Steal time registration

2011-07-24T08:49:36+00:00

This patch implements the kvm bits of the steal time infrastructure.
The most important part of it, is the steal time clock. It is an
continuous clock that shows the accumulated amount of steal time
since vcpu creation. It is supposed to survive cpu offlining/onlining.

[marcelo: fix build with CONFIG_KVM_GUEST=n]

Signed-off-by: Glauber Costa 
Acked-by: Rik van Riel 
Tested-by: Eric B Munson 
CC: Jeremy Fitzhardinge 
CC: Peter Zijlstra 
CC: Avi Kivity 
CC: Anthony Liguori 
Signed-off-by: Avi Kivity 
Signed-off-by: Marcelo Tosatti

KVM guest: Fix section mismatch derived from kvm_guest_cpu_online()

2011-03-17T16:08:25+00:00

WARNING: arch/x86/built-in.o(.text+0x1bb74): Section mismatch in reference from the function kvm_guest_cpu_online() to the function .cpuinit.text:kvm_guest_cpu_init()
The function kvm_guest_cpu_online() references
the function __cpuinit kvm_guest_cpu_init().
This is often because kvm_guest_cpu_online lacks a __cpuinit
annotation or the annotation of kvm_guest_cpu_init is wrong.

This patch fixes the warning.

Tested with linux-next (next-20101231)

Signed-off-by: Sedat Dilek 
Acked-by: Rik van Riel 
Signed-off-by: Marcelo Tosatti

KVM guest: Fix kvm clock initialization when it's configured out

2011-01-12T09:30:56+00:00

Signed-off-by: Avi Kivity

KVM: Let host know whether the guest can handle async PF in non-userspace context.

2011-01-12T09:23:21+00:00

If guest can detect that it runs in non-preemptable context it can
handle async PFs at any time, so let host know that it can send async
PF even if guest cpu is not in userspace.

Acked-by: Rik van Riel 
Signed-off-by: Gleb Natapov 
Signed-off-by: Marcelo Tosatti

KVM paravirt: Handle async PF in non preemptable context

2011-01-12T09:23:19+00:00

If async page fault is received by idle task or when preemp_count is
not zero guest cannot reschedule, so do sti; hlt and wait for page to be
ready. vcpu can still process interrupts while it waits for the page to
be ready.

Acked-by: Rik van Riel 
Signed-off-by: Gleb Natapov 
Signed-off-by: Marcelo Tosatti

KVM: Handle async PF in a guest.

2011-01-12T09:23:16+00:00

When async PF capability is detected hook up special page fault handler
that will handle async page fault events and bypass other page faults to
regular page fault handler. Also add async PF handling to nested SVM
emulation. Async PF always generates exit to L1 where vcpu thread will
be scheduled out until page is available.

Acked-by: Rik van Riel 
Signed-off-by: Gleb Natapov 
Signed-off-by: Marcelo Tosatti