Commit ecefbd94 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'kvm-3.7-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm 

Pull KVM updates from Avi Kivity:
 "Highlights of the changes for this release include support for vfio
  level triggered interrupts, improved big real mode support on older
  Intels, a streamlines guest page table walker, guest APIC speedups,
  PIO optimizations, better overcommit handling, and read-only memory."

* tag 'kvm-3.7-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (138 commits)
  KVM: s390: Fix vcpu_load handling in interrupt code
  KVM: x86: Fix guest debug across vcpu INIT reset
  KVM: Add resampling irqfds for level triggered interrupts
  KVM: optimize apic interrupt delivery
  KVM: MMU: Eliminate pointless temporary 'ac'
  KVM: MMU: Avoid access/dirty update loop if all is well
  KVM: MMU: Eliminate eperm temporary
  KVM: MMU: Optimize is_last_gpte()
  KVM: MMU: Simplify walk_addr_generic() loop
  KVM: MMU: Optimize pte permission checks
  KVM: MMU: Update accessed and dirty bits after guest pagetable walk
  KVM: MMU: Move gpte_access() out of paging_tmpl.h
  KVM: MMU: Optimize gpte_access() slightly
  KVM: MMU: Push clean gpte write protection out of gpte_access()
  KVM: clarify kvmclock documentation
  KVM: make processes waiting on vcpu mutex killable
  KVM: SVM: Make use of asm.h
  KVM: VMX: Make use of asm.h
  KVM: VMX: Make lto-friendly
  KVM: x86: lapic: Clean up find_highest_vector() and count_vectors()
  ...

Conflicts:
	arch/s390/include/asm/processor.h
	arch/x86/kvm/i8259.c
parents ce57e981 3d11df7a

Documentation/virtual/kvm/api.txt

+25 −8
Original line number Diff line number Diff line
@@ -857,7 +857,8 @@ struct kvm_userspace_memory_region { 
};



/* for kvm_memory_region::flags */

#define KVM_MEM_LOG_DIRTY_PAGES  1UL

#define KVM_MEM_LOG_DIRTY_PAGES	(1UL << 0)

#define KVM_MEM_READONLY	(1UL << 1)



This ioctl allows the user to create or modify a guest physical memory

slot.  When changing an existing slot, it may be moved in the guest
@@ -873,14 +874,17 @@ It is recommended that the lower 21 bits of guest_phys_addr and userspace_addr 
be identical.  This allows large pages in the guest to be backed by large

pages in the host.



The flags field supports just one flag, KVM_MEM_LOG_DIRTY_PAGES, which

instructs kvm to keep track of writes to memory within the slot.  See

the KVM_GET_DIRTY_LOG ioctl.

The flags field supports two flag, KVM_MEM_LOG_DIRTY_PAGES, which instructs

kvm to keep track of writes to memory within the slot.  See KVM_GET_DIRTY_LOG

ioctl.  The KVM_CAP_READONLY_MEM capability indicates the availability of the

KVM_MEM_READONLY flag.  When this flag is set for a memory region, KVM only

allows read accesses.  Writes will be posted to userspace as KVM_EXIT_MMIO

exits.



When the KVM_CAP_SYNC_MMU capability, changes in the backing of the memory

region are automatically reflected into the guest.  For example, an mmap()

that affects the region will be made visible immediately.  Another example

is madvise(MADV_DROP).

When the KVM_CAP_SYNC_MMU capability is available, changes in the backing of

the memory region are automatically reflected into the guest.  For example, an

mmap() that affects the region will be made visible immediately.  Another

example is madvise(MADV_DROP).



It is recommended to use this API instead of the KVM_SET_MEMORY_REGION ioctl.

The KVM_SET_MEMORY_REGION does not allow fine grained control over memory
@@ -1946,6 +1950,19 @@ the guest using the specified gsi pin. The irqfd is removed using 
the KVM_IRQFD_FLAG_DEASSIGN flag, specifying both kvm_irqfd.fd

and kvm_irqfd.gsi.



With KVM_CAP_IRQFD_RESAMPLE, KVM_IRQFD supports a de-assert and notify

mechanism allowing emulation of level-triggered, irqfd-based

interrupts.  When KVM_IRQFD_FLAG_RESAMPLE is set the user must pass an

additional eventfd in the kvm_irqfd.resamplefd field.  When operating

in resample mode, posting of an interrupt through kvm_irq.fd asserts

the specified gsi in the irqchip.  When the irqchip is resampled, such

as from an EOI, the gsi is de-asserted and the user is notifed via

kvm_irqfd.resamplefd.  It is the user's responsibility to re-queue

the interrupt if the device making use of it still requires service.

Note that closing the resamplefd is not sufficient to disable the

irqfd.  The KVM_IRQFD_FLAG_RESAMPLE is only necessary on assignment

and need not be specified with KVM_IRQFD_FLAG_DEASSIGN.



4.76 KVM_PPC_ALLOCATE_HTAB



Capability: KVM_CAP_PPC_ALLOC_HTAB

Documentation/virtual/kvm/hypercalls.txt

0 → 100644
+66 −0
Original line number Diff line number Diff line 
Linux KVM Hypercall:

===================

X86:

 KVM Hypercalls have a three-byte sequence of either the vmcall or the vmmcall

 instruction. The hypervisor can replace it with instructions that are

 guaranteed to be supported.



 Up to four arguments may be passed in rbx, rcx, rdx, and rsi respectively.

 The hypercall number should be placed in rax and the return value will be

 placed in rax.  No other registers will be clobbered unless explicitly stated

 by the particular hypercall.



S390:

  R2-R7 are used for parameters 1-6. In addition, R1 is used for hypercall

  number. The return value is written to R2.



  S390 uses diagnose instruction as hypercall (0x500) along with hypercall

  number in R1.



 PowerPC:

  It uses R3-R10 and hypercall number in R11. R4-R11 are used as output registers.

  Return value is placed in R3.



  KVM hypercalls uses 4 byte opcode, that are patched with 'hypercall-instructions'

  property inside the device tree's /hypervisor node.

  For more information refer to Documentation/virtual/kvm/ppc-pv.txt



KVM Hypercalls Documentation

===========================

The template for each hypercall is:

1. Hypercall name.

2. Architecture(s)

3. Status (deprecated, obsolete, active)

4. Purpose



1. KVM_HC_VAPIC_POLL_IRQ

------------------------

Architecture: x86

Status: active

Purpose: Trigger guest exit so that the host can check for pending

interrupts on reentry.



2. KVM_HC_MMU_OP

------------------------

Architecture: x86

Status: deprecated.

Purpose: Support MMU operations such as writing to PTE,

flushing TLB, release PT.



3. KVM_HC_FEATURES

------------------------

Architecture: PPC

Status: active

Purpose: Expose hypercall availability to the guest. On x86 platforms, cpuid

used to enumerate which hypercalls are available. On PPC, either device tree

based lookup ( which is also what EPAPR dictates) OR KVM specific enumeration

mechanism (which is this hypercall) can be used.



4. KVM_HC_PPC_MAP_MAGIC_PAGE

------------------------

Architecture: PPC

Status: active

Purpose: To enable communication between the hypervisor and guest there is a

shared page that contains parts of supervisor visible register state.

The guest can map this shared page to access its supervisor register through

memory using this hypercall.

Documentation/virtual/kvm/msr.txt

+20 −12
Original line number Diff line number Diff line
@@ -34,9 +34,12 @@ MSR_KVM_WALL_CLOCK_NEW: 0x4b564d00 
		time information and check that they are both equal and even.

		An odd version indicates an in-progress update.



		sec: number of seconds for wallclock.

		sec: number of seconds for wallclock at time of boot.



		nsec: number of nanoseconds for wallclock.

		nsec: number of nanoseconds for wallclock at time of boot.



	In order to get the current wallclock time, the system_time from

	MSR_KVM_SYSTEM_TIME_NEW needs to be added.



	Note that although MSRs are per-CPU entities, the effect of this

	particular MSR is global.
@@ -82,20 +85,25 @@ MSR_KVM_SYSTEM_TIME_NEW: 0x4b564d01 
		time at the time this structure was last updated. Unit is

		nanoseconds.



		tsc_to_system_mul: a function of the tsc frequency. One has

		to multiply any tsc-related quantity by this value to get

		a value in nanoseconds, besides dividing by 2^tsc_shift

		tsc_to_system_mul: multiplier to be used when converting

		tsc-related quantity to nanoseconds



		tsc_shift: cycle to nanosecond divider, as a power of two, to

		allow for shift rights. One has to shift right any tsc-related

		quantity by this value to get a value in nanoseconds, besides

		multiplying by tsc_to_system_mul.

		tsc_shift: shift to be used when converting tsc-related

		quantity to nanoseconds. This shift will ensure that

		multiplication with tsc_to_system_mul does not overflow.

		A positive value denotes a left shift, a negative value

		a right shift.



		With this information, guests can derive per-CPU time by

		doing:

		The conversion from tsc to nanoseconds involves an additional

		right shift by 32 bits. With this information, guests can

		derive per-CPU time by doing:



			time = (current_tsc - tsc_timestamp)

			time = (time * tsc_to_system_mul) >> tsc_shift

			if (tsc_shift >= 0)

				time <<= tsc_shift;

			else

				time >>= -tsc_shift;

			time = (time * tsc_to_system_mul) >> 32

			time = time + system_time



		flags: bits in this field indicate extended capabilities

Documentation/virtual/kvm/ppc-pv.txt

+22 −0
Original line number Diff line number Diff line
@@ -174,3 +174,25 @@ following: 
That way we can inject an arbitrary amount of code as replacement for a single

instruction. This allows us to check for pending interrupts when setting EE=1

for example.



Hypercall ABIs in KVM on PowerPC

=================================

1) KVM hypercalls (ePAPR)



These are ePAPR compliant hypercall implementation (mentioned above). Even

generic hypercalls are implemented here, like the ePAPR idle hcall. These are

available on all targets.



2) PAPR hypercalls



PAPR hypercalls are needed to run server PowerPC PAPR guests (-M pseries in QEMU).

These are the same hypercalls that pHyp, the POWER hypervisor implements. Some of

them are handled in the kernel, some are handled in user space. This is only

available on book3s_64.



3) OSI hypercalls



Mac-on-Linux is another user of KVM on PowerPC, which has its own hypercall (long

before KVM). This is supported to maintain compatibility. All these hypercalls get

forwarded to user space. This is only useful on book3s_32, but can be used with

book3s_64 as well.

arch/ia64/kvm/kvm-ia64.c

+17 −24
Original line number Diff line number Diff line
@@ -924,6 +924,16 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) 
	return 0;

}



int kvm_vm_ioctl_irq_line(struct kvm *kvm, struct kvm_irq_level *irq_event)

{

	if (!irqchip_in_kernel(kvm))

		return -ENXIO;



	irq_event->status = kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID,

					irq_event->irq, irq_event->level);

	return 0;

}



long kvm_arch_vm_ioctl(struct file *filp,

		unsigned int ioctl, unsigned long arg)

{
@@ -963,29 +973,6 @@ long kvm_arch_vm_ioctl(struct file *filp, 
			goto out;

		}

		break;

	case KVM_IRQ_LINE_STATUS:

	case KVM_IRQ_LINE: {

		struct kvm_irq_level irq_event;



		r = -EFAULT;

		if (copy_from_user(&irq_event, argp, sizeof irq_event))

			goto out;

		r = -ENXIO;

		if (irqchip_in_kernel(kvm)) {

			__s32 status;

			status = kvm_set_irq(kvm, KVM_USERSPACE_IRQ_SOURCE_ID,

				    irq_event.irq, irq_event.level);

			if (ioctl == KVM_IRQ_LINE_STATUS) {

				r = -EFAULT;

				irq_event.status = status;

				if (copy_to_user(argp, &irq_event,

							sizeof irq_event))

					goto out;

			}

			r = 0;

		}

		break;

		}

	case KVM_GET_IRQCHIP: {

		/* 0: PIC master, 1: PIC slave, 2: IOAPIC */

		struct kvm_irqchip chip;
@@ -1626,11 +1613,17 @@ void kvm_arch_commit_memory_region(struct kvm *kvm, 
	return;

}



void kvm_arch_flush_shadow(struct kvm *kvm)

void kvm_arch_flush_shadow_all(struct kvm *kvm)

{

	kvm_flush_remote_tlbs(kvm);

}



void kvm_arch_flush_shadow_memslot(struct kvm *kvm,

				   struct kvm_memory_slot *slot)

{

	kvm_arch_flush_shadow_all();

}



long kvm_arch_dev_ioctl(struct file *filp,

			unsigned int ioctl, unsigned long arg)

{

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