aboutsummaryrefslogtreecommitdiff
path: root/virt
AgeCommit message (Collapse)Author
2013-12-21KVM: arm-vgic: Add GICD_SPENDSGIR and GICD_CPENDSGIR handlersChristoffer Dall
Handle MMIO accesses to the two registers which should support both the case where the VMs want to read/write either of these registers and the case where user space reads/writes these registers to do save/restore of the VGIC state. Note that the added complexity compared to simple set/clear enable registers stems from the bookkeping of source cpu ids. It may be possible to change the underlying data structure to simplify the complexity, but since this is not in the critical path at all, this will do. Also note that reading this register from a live guest will not be accurate compared to on hardware, because some state may be living on the CPU LRs and the only way to give a consistent read would be to force stop all the VCPUs and request them to unqueu the LR state onto the distributor. Until we have an actual user of live reading this register, we can live with the difference. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21KVM: arm-vgic: Support unqueueing of LRs to the distChristoffer Dall
To properly access the VGIC state from user space it is very unpractical to have to loop through all the LRs in all register access functions. Instead, support moving all pending state from LRs to the distributor, but leave active state LRs alone. Note that to accurately present the active and pending state to VCPUs reading these distributor registers from a live VM, we would have to stop all other VPUs than the calling VCPU and ask each CPU to unqueue their LR state onto the distributor and add fields to track active state on the distributor side as well. We don't have any users of such functionality yet and there are other inaccuracies of the GIC emulation, so don't provide accurate synchronized access to this state just yet. However, when the time comes, having this function should help. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21KVM: arm-vgic: Add vgic reg access from dev attrChristoffer Dall
Add infrastructure to handle distributor and cpu interface register accesses through the KVM_{GET/SET}_DEVICE_ATTR interface by adding the KVM_DEV_ARM_VGIC_GRP_DIST_REGS and KVM_DEV_ARM_VGIC_GRP_CPU_REGS groups and defining the semantics of the attr field to be the MMIO offset as specified in the GICv2 specs. Missing register accesses or other changes in individual register access functions to support save/restore of the VGIC state is added in subsequent patches. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21KVM: arm-vgic: Make vgic mmio functions more genericChristoffer Dall
Rename the vgic_ranges array to vgic_dist_ranges to be more specific and to prepare for handling CPU interface register access as well (for save/restore of VGIC state). Pass offset from distributor or interface MMIO base to find_matching_range function instead of the physical address of the access in the VM memory map. This allows other callers unaware of the VM specifics, but with generic VGIC knowledge to reuse the function. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21KVM: arm-vgic: Set base addr through device APIChristoffer Dall
Support setting the distributor and cpu interface base addresses in the VM physical address space through the KVM_{SET,GET}_DEVICE_ATTR API in addition to the ARM specific API. This has the added benefit of being able to share more code in user space and do things in a uniform manner. Also deprecate the older API at the same time, but backwards compatibility will be maintained. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21KVM: arm-vgic: Support KVM_CREATE_DEVICE for VGICChristoffer Dall
Support creating the ARM VGIC device through the KVM_CREATE_DEVICE ioctl, which can then later be leveraged to use the KVM_{GET/SET}_DEVICE_ATTR, which is useful both for setting addresses in a more generic API than the ARM-specific one and is useful for save/restore of VGIC state. Adds KVM_CAP_DEVICE_CTRL to ARM capabilities. Note that we change the check for creating a VGIC from bailing out if any VCPUs were created, to bailing out if any VCPUs were ever run. This is an important distinction that shouldn't break anything, but allows creating the VGIC after the VCPUs have been created. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21ARM: KVM: Allow creating the VGIC after VCPUsChristoffer Dall
Rework the VGIC initialization slightly to allow initialization of the vgic cpu-specific state even if the irqchip (the VGIC) hasn't been created by user space yet. This is safe, because the vgic data structures are already allocated when the CPU is allocated if VGIC support is compiled into the kernel. Further, the init process does not depend on any other information and the sacrifice is a slight performance degradation for creating VMs in the no-VGIC case. The reason is that the new device control API doesn't mandate creating the VGIC before creating the VCPU and it is unreasonable to require user space to create the VGIC before creating the VCPUs. At the same time move the irqchip_in_kernel check out of kvm_vcpu_first_run_init and into the init function to make the per-vcpu and global init functions symmetric and add comments on the exported functions making it a bit easier to understand the init flow by only looking at vgic.c. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21ARM/KVM: save and restore generic timer registersAndre Przywara
For migration to work we need to save (and later restore) the state of each core's virtual generic timer. Since this is per VCPU, we can use the [gs]et_one_reg ioctl and export the three needed registers (control, counter, compare value). Though they live in cp15 space, we don't use the existing list, since they need special accessor functions and the arch timer is optional. Acked-by: Marc Zynger <marc.zyngier@arm.com> Signed-off-by: Andre Przywara <andre.przywara@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-21arm/arm64: KVM: arch_timer: Initialize cntvoff at kvm_initChristoffer Dall
Initialize the cntvoff at kvm_init_vm time, not before running the VCPUs at the first time because that will overwrite any potentially restored values from user space. Cc: Andre Przywara <andre.przywara@linaro.org> Acked-by: Marc Zynger <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2013-12-13KVM: Use cond_resched() directly and remove useless kvm_resched()Takuya Yoshikawa
Since the commit 15ad7146 ("KVM: Use the scheduler preemption notifiers to make kvm preemptible"), the remaining stuff in this function is a simple cond_resched() call with an extra need_resched() check which was there to avoid dropping VCPUs unnecessarily. Now it is meaningless. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-11-21KVM: kvm_clear_guest_page(): fix empty_zero_page usageHeiko Carstens
Using the address of 'empty_zero_page' as source address in order to clear a page is wrong. On some architectures empty_zero_page is only the pointer to the struct page of the empty_zero_page. Therefore the clear page operation would copy the contents of a couple of struct pages instead of clearing a page. For kvm only arm/arm64 are affected by this bug. To fix this use the ZERO_PAGE macro instead which will return the struct page address of the empty_zero_page on all architectures. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-11-15Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM changes from Paolo Bonzini: "Here are the 3.13 KVM changes. There was a lot of work on the PPC side: the HV and emulation flavors can now coexist in a single kernel is probably the most interesting change from a user point of view. On the x86 side there are nested virtualization improvements and a few bugfixes. ARM got transparent huge page support, improved overcommit, and support for big endian guests. Finally, there is a new interface to connect KVM with VFIO. This helps with devices that use NoSnoop PCI transactions, letting the driver in the guest execute WBINVD instructions. This includes some nVidia cards on Windows, that fail to start without these patches and the corresponding userspace changes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits) kvm, vmx: Fix lazy FPU on nested guest arm/arm64: KVM: PSCI: propagate caller endianness to the incoming vcpu arm/arm64: KVM: MMIO support for BE guest kvm, cpuid: Fix sparse warning kvm: Delete prototype for non-existent function kvm_check_iopl kvm: Delete prototype for non-existent function complete_pio hung_task: add method to reset detector pvclock: detect watchdog reset at pvclock read kvm: optimize out smp_mb after srcu_read_unlock srcu: API for barrier after srcu read unlock KVM: remove vm mmap method KVM: IOMMU: hva align mapping page size KVM: x86: trace cpuid emulation when called from emulator KVM: emulator: cleanup decode_register_operand() a bit KVM: emulator: check rex prefix inside decode_register() KVM: x86: fix emulation of "movzbl %bpl, %eax" kvm_host: typo fix KVM: x86: emulate SAHF instruction MAINTAINERS: add tree for kvm.git Documentation/kvm: add a 00-INDEX file ...
2013-11-06KVM: remove vm mmap methodGleb Natapov
It was used in conjunction with KVM_SET_MEMORY_REGION ioctl which was removed by b74a07beed0 in 2010, QEMU stopped using it in 2008, so it is time to remove the code finally. Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-11-05KVM: IOMMU: hva align mapping page sizeGreg Edwards
When determining the page size we could use to map with the IOMMU, the page size should also be aligned with the hva, not just the gfn. The gfn may not reflect the real alignment within the hugetlbfs file. Most of the time, this works fine. However, if the hugetlbfs file is backed by non-contiguous huge pages, a multi-huge page memslot starts at an unaligned offset within the hugetlbfs file, and the gfn is aligned with respect to the huge page size, kvm_host_page_size() will return the huge page size and we will use that to map with the IOMMU. When we later unpin that same memslot, the IOMMU returns the unmap size as the huge page size, and we happily unpin that many pfns in monotonically increasing order, not realizing we are spanning non-contiguous huge pages and partially unpin the wrong huge page. Ensure the IOMMU mapping page size is aligned with the hva corresponding to the gfn, which does reflect the alignment within the hugetlbfs file. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Greg Edwards <gedwards@ddn.com> Cc: stable@vger.kernel.org Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-11-04Merge branch 'kvm-ppc-queue' of git://github.com/agraf/linux-2.6 into queueGleb Natapov
Conflicts: arch/powerpc/include/asm/processor.h
2013-10-30kvm: Create non-coherent DMA registerationAlex Williamson
We currently use some ad-hoc arch variables tied to legacy KVM device assignment to manage emulation of instructions that depend on whether non-coherent DMA is present. Create an interface for this, adapting legacy KVM device assignment and adding VFIO via the KVM-VFIO device. For now we assume that non-coherent DMA is possible any time we have a VFIO group. Eventually an interface can be developed as part of the VFIO external user interface to query the coherency of a group. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30kvm/x86: Convert iommu_flags to iommu_noncoherentAlex Williamson
Default to operating in coherent mode. This simplifies the logic when we switch to a model of registering and unregistering noncoherent I/O with KVM. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30kvm: Add VFIO deviceAlex Williamson
So far we've succeeded at making KVM and VFIO mostly unaware of each other, but areas are cropping up where a connection beyond eventfds and irqfds needs to be made. This patch introduces a KVM-VFIO device that is meant to be a gateway for such interaction. The user creates the device and can add and remove VFIO groups to it via file descriptors. When a group is added, KVM verifies the group is valid and gets a reference to it via the VFIO external user interface. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-30KVM: use a more sensible error number when debugfs directory creation failsPaolo Bonzini
I don't know if this was due to cut and paste, or somebody was really using a D20 to pick the error code for kvm_init_debugfs as suggested by Linus (EFAULT is 14, so the possibility cannot be entirely ruled out). In any case, this patch fixes it. Reported-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-28KVM: Mapping IOMMU pages after updating memslotYang Zhang
In kvm_iommu_map_pages(), we need to know the page size via call kvm_host_page_size(). And it will check whether the target slot is valid before return the right page size. Currently, we will map the iommu pages when creating a new slot. But we call kvm_iommu_map_pages() during preparing the new slot. At that time, the new slot is not visible by domain(still in preparing). So we cannot get the right page size from kvm_host_page_size() and this will break the IOMMU super page logic. The solution is to map the iommu pages after we insert the new slot into domain. Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com> Tested-by: Patrick Lu <patrick.lu@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-10-17Powerpc KVM work is based on a commit after rc4.Gleb Natapov
Merging master into next to satisfy the dependencies. Conflicts: arch/arm/kvm/reset.c
2013-10-17kvm: Add struct kvm arg to memslot APIsAneesh Kumar K.V
We will use that in the later patch to find the kvm ops handler Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-17kvm: powerpc: book3s: Support building HV and PR KVM as moduleAneesh Kumar K.V
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [agraf: squash in compile fix] Signed-off-by: Alexander Graf <agraf@suse.de>
2013-10-15KVM: Drop FOLL_GET in GUP when doing async page faultchai wen
Page pinning is not mandatory in kvm async page fault processing since after async page fault event is delivered to a guest it accesses page once again and does its own GUP. Drop the FOLL_GET flag in GUP in async_pf code, and do some simplifying in check/clear processing. Suggested-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Gu zheng <guz.fnst@cn.fujitsu.com> Signed-off-by: chai wen <chaiw.fnst@cn.fujitsu.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-03virt/kvm/iommu.c: Add leading zeros to device's BDF notation in debug messagesAndre Richter
When KVM (de)assigns PCI(e) devices to VMs, a debug message is printed including the BDF notation of the respective device. Currently, the BDF notation does not have the commonly used leading zeros. This produces messages like "assign device 0:1:8.0", which look strange at first sight. The patch fixes this by exchanging the printk(KERN_DEBUG ...) with dev_info() and also inserts "kvm" into the debug message, so that it is obvious where the message comes from. Also reduces LoC. Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Andre Richter <andre.o.richter@gmail.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-10-03Fix NULL dereference in gfn_to_hva_prot()Gleb Natapov
gfn_to_memslot() can return NULL or invalid slot. We need to check slot validity before accessing it. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-09-30KVM: Convert kvm_lock back to non-raw spinlockPaolo Bonzini
In commit e935b8372cf8 ("KVM: Convert kvm_lock to raw_spinlock"), the kvm_lock was made a raw lock. However, the kvm mmu_shrink() function tries to grab the (non-raw) mmu_lock within the scope of the raw locked kvm_lock being held. This leads to the following: BUG: sleeping function called from invalid context at kernel/rtmutex.c:659 in_atomic(): 1, irqs_disabled(): 0, pid: 55, name: kswapd0 Preemption disabled at:[<ffffffffa0376eac>] mmu_shrink+0x5c/0x1b0 [kvm] Pid: 55, comm: kswapd0 Not tainted 3.4.34_preempt-rt Call Trace: [<ffffffff8106f2ad>] __might_sleep+0xfd/0x160 [<ffffffff817d8d64>] rt_spin_lock+0x24/0x50 [<ffffffffa0376f3c>] mmu_shrink+0xec/0x1b0 [kvm] [<ffffffff8111455d>] shrink_slab+0x17d/0x3a0 [<ffffffff81151f00>] ? mem_cgroup_iter+0x130/0x260 [<ffffffff8111824a>] balance_pgdat+0x54a/0x730 [<ffffffff8111fe47>] ? set_pgdat_percpu_threshold+0xa7/0xd0 [<ffffffff811185bf>] kswapd+0x18f/0x490 [<ffffffff81070961>] ? get_parent_ip+0x11/0x50 [<ffffffff81061970>] ? __init_waitqueue_head+0x50/0x50 [<ffffffff81118430>] ? balance_pgdat+0x730/0x730 [<ffffffff81060d2b>] kthread+0xdb/0xe0 [<ffffffff8106e122>] ? finish_task_switch+0x52/0x100 [<ffffffff817e1e94>] kernel_thread_helper+0x4/0x10 [<ffffffff81060c50>] ? __init_kthread_worker+0x After the previous patch, kvm_lock need not be a raw spinlock anymore, so change it back. Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: kvm@vger.kernel.org Cc: gleb@redhat.com Cc: jan.kiszka@siemens.com Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-30KVM: protect kvm_usage_count with its own spinlockPaolo Bonzini
The VM list need not be protected by a raw spinlock. Separate the two so that kvm_lock can be made non-raw. Cc: kvm@vger.kernel.org Cc: gleb@redhat.com Cc: jan.kiszka@siemens.com Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-30KVM: cleanup (physical) CPU hotplugPaolo Bonzini
Remove the useless argument, and do not do anything if there are no VMs running at the time of the hotplug. Cc: kvm@vger.kernel.org Cc: gleb@redhat.com Cc: jan.kiszka@siemens.com Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-24kvm: remove .done from struct kvm_async_pfRadim Krčmář
'.done' is used to mark the completion of 'async_pf_execute()', but 'cancel_work_sync()' returns true when the work was canceled, so we use it instead. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-17kvm: free resources after canceling async_pfRadim Krčmář
When we cancel 'async_pf_execute()', we should behave as if the work was never scheduled in 'kvm_setup_async_pf()'. Fixes a bug when we can't unload module because the vm wasn't destroyed. Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-17KVM: mmu: allow page tables to be in read-only slotsPaolo Bonzini
Page tables in a read-only memory slot will currently cause a triple fault because the page walker uses gfn_to_hva and it fails on such a slot. OVMF uses such a page table; however, real hardware seems to be fine with that as long as the accessed/dirty bits are set. Save whether the slot is readonly, and later check it when updating the accessed and dirty bits. Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-09-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile 1 from Al Viro: "Unfortunately, this merge window it'll have a be a lot of small piles - my fault, actually, for not keeping #for-next in anything that would resemble a sane shape ;-/ This pile: assorted fixes (the first 3 are -stable fodder, IMO) and cleanups + %pd/%pD formats (dentry/file pathname, up to 4 last components) + several long-standing patches from various folks. There definitely will be a lot more (starting with Miklos' check_submount_and_drop() series)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits) direct-io: Handle O_(D)SYNC AIO direct-io: Implement generic deferred AIO completions add formats for dentry/file pathnames kvm eventfd: switch to fdget powerpc kvm: use fdget switch fchmod() to fdget switch epoll_ctl() to fdget switch copy_module_from_fd() to fdget git simplify nilfs check for busy subtree ibmasmfs: don't bother passing superblock when not needed don't pass superblock to hypfs_{mkdir,create*} don't pass superblock to hypfs_diag_create_files don't pass superblock to hypfs_vm_create_files() oprofile: get rid of pointless forward declarations of struct super_block oprofilefs_create_...() do not need superblock argument oprofilefs_mkdir() doesn't need superblock argument don't bother with passing superblock to oprofile_create_stats_files() oprofile: don't bother with passing superblock to ->create_files() don't bother passing sb to oprofile_create_files() coh901318: don't open-code simple_read_from_buffer() ...
2013-09-03kvm eventfd: switch to fdgetAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-08-30ARM: KVM: Bugfix: vgic_bytemap_get_reg per cpu regsChristoffer Dall
For bytemaps each IRQ field is 1 byte wide, so we pack 4 irq fields in one word and since there are 32 private (per cpu) irqs, we have 8 private u32 fields on the vgic_bytemap struct. We shift the offset from the base of the register group right by 2, giving us the word index instead of the field index. But then there are 8 private words, not 4, which is also why we subtract 8 words from the offset of the shared words. Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-30ARM: KVM: vgic: fix GICD_ICFGRn accessMarc Zyngier
All the code in handle_mmio_cfg_reg() assumes the offset has been shifted right to accomodate for the 2:1 bit compression, but this is only done when getting the register address. Shift the offset early so the code works mostly unchanged. Reported-by: Zhaobo (Bob, ERC) <zhaobo@huawei.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-30ARM: KVM: vgic: simplify vgic_get_target_regMarc Zyngier
vgic_get_target_reg is quite complicated, for no good reason. Actually, it is fairly easy to write it in a much more efficient way by using the target CPU array instead of the bitmap. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-28KVM: rename __kvm_io_bus_sort_cmp to kvm_io_bus_cmpPaolo Bonzini
This is the type-safe comparison function, so the double-underscore is not related. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-27kvm: optimize away THP checks in kvm_is_mmio_pfn()Andrea Arcangeli
The checks on PG_reserved in the page structure on head and tail pages aren't necessary because split_huge_page wouldn't transfer the PG_reserved bit from head to tail anyway. This was a forward-thinking check done in the case PageReserved was set by a driver-owned page mapped in userland with something like remap_pfn_range in a VM_PFNMAP region, but using hugepmds (not possible right now). It was meant to be very safe, but it's overkill as it's unlikely split_huge_page could ever run without the driver noticing and tearing down the hugepage itself. And if a driver in the future will really want to map a reserved hugepage in userland using an huge pmd it should simply take care of marking all subpages reserved too to keep KVM safe. This of course would require such a hypothetical driver to tear down the huge pmd itself and splitting the hugepage itself, instead of relaying on split_huge_page, but that sounds very reasonable, especially considering split_huge_page wouldn't currently transfer the reserved bit anyway. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-08-26kvm: use anon_inode_getfd() with O_CLOEXEC flagYann Droneaud
KVM uses anon_inode_get() to allocate file descriptors as part of some of its ioctls. But those ioctls are lacking a flag argument allowing userspace to choose options for the newly opened file descriptor. In such case it's advised to use O_CLOEXEC by default so that userspace is allowed to choose, without race, if the file descriptor is going to be inherited across exec(). This patch set O_CLOEXEC flag on all file descriptors created with anon_inode_getfd() to not leak file descriptors across exec(). Signed-off-by: Yann Droneaud <ydroneaud@opteya.com> Link: http://lkml.kernel.org/r/cover.1377372576.git.ydroneaud@opteya.com Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-07-29KVM: introduce __kvm_io_bus_sort_cmpPaolo Bonzini
kvm_io_bus_sort_cmp is used also directly, not just as a callback for sort and bsearch. In these cases, it is handy to have a type-safe variant. This patch introduces such a variant, __kvm_io_bus_sort_cmp, and uses it throughout kvm_main.c. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-18KVM: Introduce kvm_arch_memslots_updated()Takuya Yoshikawa
This is called right after the memslots is updated, i.e. when the result of update_memslots() gets installed in install_new_memslots(). Since the memslots needs to be updated twice when we delete or move a memslot, kvm_arch_commit_memory_region() does not correspond to this exactly. In the following patch, x86 will use this new API to check if the mmio generation has reached its maximum value, in which case mmio sptes need to be flushed out. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Acked-by: Alexander Graf <agraf@suse.de> Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-18KVM: kvm-io: support cookiesCornelia Huck
Add new functions kvm_io_bus_{read,write}_cookie() that allows users of the kvm io infrastructure to use a cookie value to speed up lookup of a device on an io bus. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-07-03Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Paolo Bonzini: "On the x86 side, there are some optimizations and documentation updates. The big ARM/KVM change for 3.11, support for AArch64, will come through Catalin Marinas's tree. s390 and PPC have misc cleanups and bugfixes" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (87 commits) KVM: PPC: Ignore PIR writes KVM: PPC: Book3S PR: Invalidate SLB entries properly KVM: PPC: Book3S PR: Allow guest to use 1TB segments KVM: PPC: Book3S PR: Don't keep scanning HPTEG after we find a match KVM: PPC: Book3S PR: Fix invalidation of SLB entry 0 on guest entry KVM: PPC: Book3S PR: Fix proto-VSID calculations KVM: PPC: Guard doorbell exception with CONFIG_PPC_DOORBELL KVM: Fix RTC interrupt coalescing tracking kvm: Add a tracepoint write_tsc_offset KVM: MMU: Inform users of mmio generation wraparound KVM: MMU: document fast invalidate all mmio sptes KVM: MMU: document fast invalidate all pages KVM: MMU: document fast page fault KVM: MMU: document mmio page fault KVM: MMU: document write_flooding_count KVM: MMU: document clear_spte_count KVM: MMU: drop kvm_mmu_zap_mmio_sptes KVM: MMU: init kvm generation close to mmio wrap-around value KVM: MMU: add tracepoint for check_mmio_spte KVM: MMU: fast invalidate all mmio sptes ...
2013-06-27Merge git://git.linaro.org/people/cdall/linux-kvm-arm.git tags/kvm-arm-3.11 ↵Gleb Natapov
into queue KVM/ARM pull request for 3.11 merge window * tag 'kvm-arm-3.11' of git://git.linaro.org/people/cdall/linux-kvm-arm.git: ARM: kvm: don't include drivers/virtio/Kconfig Update MAINTAINERS: KVM/ARM work now funded by Linaro arm/kvm: Cleanup KVM_ARM_MAX_VCPUS logic ARM: KVM: clear exclusive monitor on all exception returns ARM: KVM: add missing dsb before invalidating Stage-2 TLBs ARM: KVM: perform save/restore of PAR ARM: KVM: get rid of S2_PGD_SIZE ARM: KVM: don't special case PC when doing an MMIO ARM: KVM: use phys_addr_t instead of unsigned long long for HYP PGDs ARM: KVM: remove dead prototype for __kvm_tlb_flush_vmid ARM: KVM: Don't handle PSCI calls via SMC ARM: KVM: Allow host virt timer irq to be different from guest timer virt irq
2013-06-27KVM: Fix RTC interrupt coalescing trackingGleb Natapov
This reverts most of the f1ed0450a5fac7067590317cbf027f566b6ccbca. After the commit kvm_apic_set_irq() no longer returns accurate information about interrupt injection status if injection is done into disabled APIC. RTC interrupt coalescing tracking relies on the information to be accurate and cannot recover if it is not. Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-06-26ARM: KVM: Allow host virt timer irq to be different from guest timer virt irqAnup Patel
The arch_timer irq numbers (or PPI numbers) are implementation dependent, so the host virtual timer irq number can be different from guest virtual timer irq number. This patch ensures that host virtual timer irq number is read from DTB and guest virtual timer irq is determined based on vcpu target type. Signed-off-by: Anup Patel <anup.patel@linaro.org> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu>
2013-06-04kvm: exclude ioeventfd from counting kvm_io_range limitAmos Kong
We can easily reach the 1000 limit by start VM with a couple hundred I/O devices (multifunction=on). The hardcode limit already been adjusted 3 times (6 ~ 200 ~ 300 ~ 1000). In userspace, we already have maximum file descriptor to limit ioeventfd count. But kvm_io_bus devices also are used for pit, pic, ioapic, coalesced_mmio. They couldn't be limited by maximum file descriptor. Currently only ioeventfds take too much kvm_io_bus devices, so just exclude it from counting kvm_io_range limit. Also fixed one indent issue in kvm_host.h Signed-off-by: Amos Kong <akong@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-19ARM: KVM: move GIC/timer code to a common locationMarc Zyngier
As KVM/arm64 is looming on the horizon, it makes sense to move some of the common code to a single location in order to reduce duplication. The code could live anywhere. Actually, most of KVM is already built with a bunch of ugly ../../.. hacks in the various Makefiles, so we're not exactly talking about style here. But maybe it is time to start moving into a less ugly direction. The include files must be in a "public" location, as they are accessed from non-KVM files (arch/arm/kernel/asm-offsets.c). For this purpose, introduce two new locations: - virt/kvm/arm/ : x86 and ia64 already share the ioapic code in virt/kvm, so this could be seen as a (very ugly) precedent. - include/kvm/ : there is already an include/xen, and while the intent is slightly different, this seems as good a location as any Eventually, we should probably have independant Makefiles at every levels (just like everywhere else in the kernel), but this is just the first step. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-05-14KVM: x86: Remove support for reporting coalesced APIC IRQsJan Kiszka
Since the arrival of posted interrupt support we can no longer guarantee that coalesced IRQs are always reported to the IRQ source. Moreover, accumulated APIC timer events could cause a busy loop when a VCPU should rather be halted. The consensus is to remove coalesced tracking from the LAPIC. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Acked-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>