kernel.git/virt/kvm/kvm_main.c, branch linux-4.5.y

KVM: fix spin_lock_init order on x86

2016-04-12T14:33:10Z

commit e9ad4ec8379ad1ba6f68b8ca1c26b50b5ae0a327 upstream. Moving the initialization earlier is needed in 4.6 because kvm_arch_init_vm is now using mmu_lock, causing lockdep to complain: [ 284.440294] INFO: trying to register non-static key. [ 284.445259] the code is fine but needs lockdep annotation. [ 284.450736] turning off the locking correctness validator. ... [ 284.528318] [] lock_acquire+0xd3/0x240 [ 284.533733] [] ? kvm_page_track_register_notifier+0x20/0x60 [kvm] [ 284.541467] [] _raw_spin_lock+0x41/0x80 [ 284.546960] [] ? kvm_page_track_register_notifier+0x20/0x60 [kvm] [ 284.554707] [] kvm_page_track_register_notifier+0x20/0x60 [kvm] [ 284.562281] [] kvm_mmu_init_vm+0x20/0x30 [kvm] [ 284.568381] [] kvm_arch_init_vm+0x1ea/0x200 [kvm] [ 284.574740] [] kvm_dev_ioctl+0xbf/0x4d0 [kvm] However, it also helps fixing a preexisting problem, which is why this patch is also good for stable kernels: kvm_create_vm was incrementing current->mm->mm_count but not decrementing it at the out_err label (in case kvm_init_mmu_notifier failed). The new initialization order makes it possible to add the required mmdrop without adding a new error label. Reported-by: Borislav Petkov Signed-off-by: Paolo Bonzini Signed-off-by: Greg Kroah-Hartman

kvm: cap halt polling at exactly halt_poll_ns

2016-03-09T10:54:14Z

When growing halt-polling, there is no check that the poll time exceeds the limit. It's possible for vcpu->halt_poll_ns grow once past halt_poll_ns, and stay there until a halt which takes longer than vcpu->halt_poll_ns. For example, booting a Linux guest with halt_poll_ns=11000: ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 0 (shrink 10000) ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 10000 (grow 0) ... kvm:kvm_halt_poll_ns: vcpu 0: halt_poll_ns 20000 (grow 10000) Signed-off-by: David Matlack Fixes: aca6ff29c4063a8d467cdee241e6b3bf7dc4a171 Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini

kvm: rename pfn_t to kvm_pfn_t

2016-01-16T01:56:32Z

To date, we have implemented two I/O usage models for persistent memory, PMEM (a persistent "ram disk") and DAX (mmap persistent memory into userspace). This series adds a third, DAX-GUP, that allows DAX mappings to be the target of direct-i/o. It allows userspace to coordinate DMA/RDMA from/to persistent memory. The implementation leverages the ZONE_DEVICE mm-zone that went into 4.3-rc1 (also discussed at kernel summit) to flag pages that are owned and dynamically mapped by a device driver. The pmem driver, after mapping a persistent memory range into the system memmap via devm_memremap_pages(), arranges for DAX to distinguish pfn-only versus page-backed pmem-pfns via flags in the new pfn_t type. The DAX code, upon seeing a PFN_DEV+PFN_MAP flagged pfn, flags the resulting pte(s) inserted into the process page tables with a new _PAGE_DEVMAP flag. Later, when get_user_pages() is walking ptes it keys off _PAGE_DEVMAP to pin the device hosting the page range active. Finally, get_page() and put_page() are modified to take references against the device driver established page mapping. Finally, this need for "struct page" for persistent memory requires memory capacity to store the memmap array. Given the memmap array for a large pool of persistent may exhaust available DRAM introduce a mechanism to allocate the memmap from persistent memory. The new "struct vmem_altmap *" parameter to devm_memremap_pages() enables arch_add_memory() to use reserved pmem capacity rather than the page allocator. This patch (of 18): The core has developed a need for a "pfn_t" type [1]. Move the existing pfn_t in KVM to kvm_pfn_t [2]. [1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002199.html [2]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002218.html Signed-off-by: Dan Williams Acked-by: Christoffer Dall Cc: Paolo Bonzini Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

KVM: move architecture-dependent requests to arch/

2016-01-08T18:04:36Z

Since the numbers now overlap, it makes sense to enumerate them in asm/kvm_host.h rather than linux/kvm_host.h. Functions that refer to architecture-specific requests are also moved to arch/. Signed-off-by: Paolo Bonzini

KVM: Remove unnecessary debugfs dentry references

2015-11-30T11:47:05Z

KVM creates debugfs files to export VM statistics to userland. To be able to remove them on kvm exit it tracks the files' dentries. Since their parent directory is also tracked and since each parent direntry knows its children we can easily remove them by using debugfs_remove_recursive(kvm_debugfs_dir). Therefore we don't need the extra tracking in the kvm_stats_debugfs_item anymore. Signed-off-by: Janosch Frank Reviewed-By: Sascha Silbe Acked-by: Christian Borntraeger Signed-off-by: Christian Borntraeger

KVM: Use common function for VCPU lookup by id

2015-11-30T11:47:04Z

Let's reuse the new common function for VPCU lookup by id. Reviewed-by: Christian Borntraeger Reviewed-by: Dominik Dingel Signed-off-by: David Hildenbrand Signed-off-by: Christian Borntraeger [split out the new function into a separate patch]

KVM: kvm_is_visible_gfn can be boolean

2015-11-25T16:24:23Z

This patch makes kvm_is_visible_gfn return bool due to this particular function only using either one or zero as its return value. No functional change. Signed-off-by: Yaowei Bai Signed-off-by: Paolo Bonzini

Merge tag 'kvm-arm-for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2015-11-04T15:24:17Z

KVM/ARM Changes for v4.4-rc1 Includes a number of fixes for the arch-timer, introducing proper level-triggered semantics for the arch-timers, a series of patches to synchronously halt a guest (prerequisite for IRQ forwarding), some tracepoint improvements, a tweak for the EL2 panic handlers, some more VGIC cleanups getting rid of redundant state, and finally a stylistic change that gets rid of some ctags warnings. Conflicts: arch/x86/include/asm/kvm_host.h

KVM: Add kvm_arch_vcpu_{un}blocking callbacks

2015-10-22T21:01:41Z

Some times it is useful for architecture implementations of KVM to know when the VCPU thread is about to block or when it comes back from blocking (arm/arm64 needs to know this to properly implement timers, for example). Therefore provide a generic architecture callback function in line with what we do elsewhere for KVM generic-arch interactions. Reviewed-by: Marc Zyngier Signed-off-by: Christoffer Dall

KVM: Update Posted-Interrupts Descriptor when vCPU is blocked

2015-10-01T13:06:53Z

This patch updates the Posted-Interrupts Descriptor when vCPU is blocked. pre-block: - Add the vCPU to the blocked per-CPU list - Set 'NV' to POSTED_INTR_WAKEUP_VECTOR post-block: - Remove the vCPU from the per-CPU list Signed-off-by: Feng Wu [Concentrate invocation of pre/post-block hooks to vcpu_block. - Paolo] Signed-off-by: Paolo Bonzini