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* KVM: use slowpath for cross page cached accessesRadim Krčmář2015-05-061-2/+2
| | | | | | | | | | | | | | | | | | | commit ca3f0874723fad81d0c701b63ae3a17a408d5f25 upstream. kvm_write_guest_cached() does not mark all written pages as dirty and code comments in kvm_gfn_to_hva_cache_init() talk about NULL memslot with cross page accesses. Fix all the easy way. The check is '<= 1' to have the same result for 'len = 0' cache anywhere in the page. (nr_pages_needed is 0 on page boundary.) Fixes: 8f964525a121 ("KVM: Allow cross page reads and writes from cached translations.") Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Message-Id: <20150408121648.GA3519@potion.brq.redhat.com> Reviewed-by: Wanpeng Li <wanpeng.li@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kvm: don't take vcpu mutex for obviously invalid vcpu ioctlsDavid Matlack2014-10-301-0/+4
| | | | | | | | | | | | | | | | | | commit 2ea75be3219571d0ec009ce20d9971e54af96e09 upstream. vcpu ioctls can hang the calling thread if issued while a vcpu is running. However, invalid ioctls can happen when userspace tries to probe the kind of file descriptors (e.g. isatty() calls ioctl(TCGETS)); in that case, we know the ioctl is going to be rejected as invalid anyway and we can fail before trying to take the vcpu mutex. This patch does not change functionality, it just makes invalid ioctls fail faster. Signed-off-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* mm: close PageTail raceDavid Rientjes2014-04-031-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit 668f9abbd4334e6c29fa8acd71635c4f9101caa7 upstream. Commit bf6bddf1924e ("mm: introduce compaction and migration for ballooned pages") introduces page_count(page) into memory compaction which dereferences page->first_page if PageTail(page). This results in a very rare NULL pointer dereference on the aforementioned page_count(page). Indeed, anything that does compound_head(), including page_count() is susceptible to racing with prep_compound_page() and seeing a NULL or dangling page->first_page pointer. This patch uses Andrea's implementation of compound_trans_head() that deals with such a race and makes it the default compound_head() implementation. This includes a read memory barrier that ensures that if PageTail(head) is true that we return a head page that is neither NULL nor dangling. The patch then adds a store memory barrier to prep_compound_page() to ensure page->first_page is set. This is the safest way to ensure we see the head page that we are expecting, PageTail(page) is already in the unlikely() path and the memory barriers are unfortunately required. Hugetlbfs is the exception, we don't enforce a store memory barrier during init since no race is possible. Signed-off-by: David Rientjes <rientjes@google.com> Cc: Holger Kiehl <Holger.Kiehl@dwd.de> Cc: Christoph Lameter <cl@linux.com> Cc: Rafael Aquini <aquini@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Michal Hocko <mhocko@suse.cz> Cc: Mel Gorman <mgorman@suse.de> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* KVM: Improve create VCPU parameter (CVE-2013-4587)Andy Honig2013-12-201-0/+3
| | | | | | | | | | | | | | | | | commit 338c7dbadd2671189cec7faf64c84d01071b3f96 upstream. In multiple functions the vcpu_id is used as an offset into a bitfield. Ag malicious user could specify a vcpu_id greater than 255 in order to set or clear bits in kernel memory. This could be used to elevate priveges in the kernel. This patch verifies that the vcpu_id provided is less than 255. The api documentation already specifies that the vcpu_id must be less than max_vcpus, but this is currently not checked. Reported-by: Andrew Honig <ahonig@google.com> Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* Merge tag 'kvm-3.10-2' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2013-05-101-5/+13
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm fixes from Gleb Natapov: "Most of the fixes are in the emulator since now we emulate more than we did before for correctness sake we see more bugs there, but there is also an OOPS fixed and corruption of xcr0 register." * tag 'kvm-3.10-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: emulator: emulate SALC KVM: emulator: emulate XLAT KVM: emulator: emulate AAM KVM: VMX: fix halt emulation while emulating invalid guest sate KVM: Fix kvm_irqfd_init initialization KVM: x86: fix maintenance of guest/host xcr0 state
| * KVM: Fix kvm_irqfd_init initializationAsias He2013-05-081-5/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit a0f155e96 'KVM: Initialize irqfd from kvm_init()', when kvm_init() is called the second time (e.g kvm-amd.ko and kvm-intel.ko), kvm_arch_init() will fail with -EEXIST, then kvm_irqfd_exit() will be called on the error handling path. This way, the kvm_irqfd system will not be ready. This patch fix the following: BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff81c0721e>] _raw_spin_lock+0xe/0x30 PGD 0 Oops: 0002 [#1] SMP Modules linked in: vhost_net CPU 6 Pid: 4257, comm: qemu-system-x86 Not tainted 3.9.0-rc3+ #757 Dell Inc. OptiPlex 790/0V5HMK RIP: 0010:[<ffffffff81c0721e>] [<ffffffff81c0721e>] _raw_spin_lock+0xe/0x30 RSP: 0018:ffff880221721cc8 EFLAGS: 00010046 RAX: 0000000000000100 RBX: ffff88022dcc003f RCX: ffff880221734950 RDX: ffff8802208f6ca8 RSI: 000000007fffffff RDI: 0000000000000000 RBP: ffff880221721cc8 R08: 0000000000000002 R09: 0000000000000002 R10: 00007f7fd01087e0 R11: 0000000000000246 R12: ffff8802208f6ca8 R13: 0000000000000080 R14: ffff880223e2a900 R15: 0000000000000000 FS: 00007f7fd38488e0(0000) GS:ffff88022dcc0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000022309f000 CR4: 00000000000427e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process qemu-system-x86 (pid: 4257, threadinfo ffff880221720000, task ffff880222bd5640) Stack: ffff880221721d08 ffffffff810ac5c5 ffff88022431dc00 0000000000000086 0000000000000080 ffff880223e2a900 ffff8802208f6ca8 0000000000000000 ffff880221721d48 ffffffff810ac8fe 0000000000000000 ffff880221734000 Call Trace: [<ffffffff810ac5c5>] __queue_work+0x45/0x2d0 [<ffffffff810ac8fe>] queue_work_on+0x8e/0xa0 [<ffffffff810ac949>] queue_work+0x19/0x20 [<ffffffff81009b6b>] irqfd_deactivate+0x4b/0x60 [<ffffffff8100a69d>] kvm_irqfd+0x39d/0x580 [<ffffffff81007a27>] kvm_vm_ioctl+0x207/0x5b0 [<ffffffff810c9545>] ? update_curr+0xf5/0x180 [<ffffffff811b66e8>] do_vfs_ioctl+0x98/0x550 [<ffffffff810c1f5e>] ? finish_task_switch+0x4e/0xe0 [<ffffffff81c054aa>] ? __schedule+0x2ea/0x710 [<ffffffff811b6bf7>] sys_ioctl+0x57/0x90 [<ffffffff8140ae9e>] ? trace_hardirqs_on_thunk+0x3a/0x3c [<ffffffff81c0f602>] system_call_fastpath+0x16/0x1b Code: c1 ea 08 38 c2 74 0f 66 0f 1f 44 00 00 f3 90 0f b6 03 38 c2 75 f7 48 83 c4 08 5b c9 c3 55 48 89 e5 66 66 66 66 90 b8 00 01 00 00 <f0> 66 0f c1 07 89 c2 66 c1 ea 08 38 c2 74 0c 0f 1f 00 f3 90 0f RIP [<ffffffff81c0721e>] _raw_spin_lock+0xe/0x30 RSP <ffff880221721cc8> CR2: 0000000000000000 ---[ end trace 13fb1e4b6e5ab21f ]--- Signed-off-by: Asias He <asias@redhat.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* | Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linusLinus Torvalds2013-05-101-1/+1
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull MIPS updates from Ralf Baechle: - More work on DT support for various platforms - Various fixes that were to late to make it straight into 3.9 - Improved platform support, in particular the Netlogic XLR and BCM63xx, and the SEAD3 and Malta eval boards. - Support for several Ralink SOC families. - Complete support for the microMIPS ASE which basically reencodes the existing MIPS32/MIPS64 ISA to use non-constant size instructions. - Some fallout from LTO work which remove old cruft and will generally make the MIPS kernel easier to maintain and resistant to compiler optimization, even in absence of LTO. - KVM support. While MIPS has announced hardware virtualization extensions this KVM extension uses trap and emulate mode for virtualization of MIPS32. More KVM work to add support for VZ hardware virtualizaiton extensions and MIPS64 will probably already be merged for 3.11. Most of this has been sitting in -next for a long time. All defconfigs have been build or run time tested except three for which fixes are being sent by other maintainers. Semantic conflict with kvm updates done as per Ralf * 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (118 commits) MIPS: Add new GIC clockevent driver. MIPS: Formatting clean-ups for clocksources. MIPS: Refactor GIC clocksource code. MIPS: Move 'gic_frequency' to common location. MIPS: Move 'gic_present' to common location. MIPS: MIPS16e: Add unaligned access support. MIPS: MIPS16e: Support handling of delay slots. MIPS: MIPS16e: Add instruction formats. MIPS: microMIPS: Optimise 'strnlen' core library function. MIPS: microMIPS: Optimise 'strlen' core library function. MIPS: microMIPS: Optimise 'strncpy' core library function. MIPS: microMIPS: Optimise 'memset' core library function. MIPS: microMIPS: Add configuration option for microMIPS kernel. MIPS: microMIPS: Disable LL/SC and fix linker bug. MIPS: microMIPS: Add vdso support. MIPS: microMIPS: Add unaligned access support. MIPS: microMIPS: Support handling of delay slots. MIPS: microMIPS: Add support for exception handling. MIPS: microMIPS: Floating point support. MIPS: microMIPS: Fix macro naming in micro-assembler. ...
| * Merge branch 'next/kvm' into mips-for-linux-nextRalf Baechle2013-05-091-1/+1
| |\
| | * KVM/MIPS32: Do not call vcpu_load when injecting interrupts.Sanjay Lal2013-05-091-1/+1
| | | | | | | | | | | | | | | | | | | | | Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* | | Merge tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2013-05-051-47/+211
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull kvm updates from Gleb Natapov: "Highlights of the updates are: general: - new emulated device API - legacy device assignment is now optional - irqfd interface is more generic and can be shared between arches x86: - VMCS shadow support and other nested VMX improvements - APIC virtualization and Posted Interrupt hardware support - Optimize mmio spte zapping ppc: - BookE: in-kernel MPIC emulation with irqfd support - Book3S: in-kernel XICS emulation (incomplete) - Book3S: HV: migration fixes - BookE: more debug support preparation - BookE: e6500 support ARM: - reworking of Hyp idmaps s390: - ioeventfd for virtio-ccw And many other bug fixes, cleanups and improvements" * tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) kvm: Add compat_ioctl for device control API KVM: x86: Account for failing enable_irq_window for NMI window request KVM: PPC: Book3S: Add API for in-kernel XICS emulation kvm/ppc/mpic: fix missing unlock in set_base_addr() kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write kvm/ppc/mpic: remove users kvm/ppc/mpic: fix mmio region lists when multiple guests used kvm/ppc/mpic: remove default routes from documentation kvm: KVM_CAP_IOMMU only available with device assignment ARM: KVM: iterate over all CPUs for CPU compatibility check KVM: ARM: Fix spelling in error message ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally KVM: ARM: Fix API documentation for ONE_REG encoding ARM: KVM: promote vfp_host pointer to generic host cpu context ARM: KVM: add architecture specific hook for capabilities ARM: KVM: perform HYP initilization for hotplugged CPUs ARM: KVM: switch to a dual-step HYP init code ARM: KVM: rework HYP page table freeing ARM: KVM: enforce maximum size for identity mapped code ARM: KVM: move to a KVM provided HYP idmap ...
| * | kvm: Add compat_ioctl for device control APIScott Wood2013-05-051-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | This API shouldn't have 32/64-bit issues, but VFS assumes it does unless told otherwise. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
| * | KVM: PPC: Book3S: Add API for in-kernel XICS emulationPaul Mackerras2013-05-021-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds the API for userspace to instantiate an XICS device in a VM and connect VCPUs to it. The API consists of a new device type for the KVM_CREATE_DEVICE ioctl, a new capability KVM_CAP_IRQ_XICS, which functions similarly to KVM_CAP_IRQ_MPIC, and the KVM_IRQ_LINE ioctl, which is used to assert and deassert interrupt inputs of the XICS. The XICS device has one attribute group, KVM_DEV_XICS_GRP_SOURCES. Each attribute within this group corresponds to the state of one interrupt source. The attribute number is the same as the interrupt source number. This does not support irq routing or irqfd yet. Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Alexander Graf <agraf@suse.de>
| * | kvm: destroy emulated devices on VM exitScott Wood2013-04-261-13/+16
| | | | | | | | | | | | | | | | | | | | | | | | The hassle of getting refcounting right was greater than the hassle of keeping a list of devices to destroy on VM exit. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
| * | kvm/ppc/mpic: in-kernel MPIC emulationScott Wood2013-04-261-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | Hook the MPIC code up to the KVM interfaces, add locking, etc. Signed-off-by: Scott Wood <scottwood@freescale.com> [agraf: add stub function for kvmppc_mpic_set_epr, non-booke, 64bit] Signed-off-by: Alexander Graf <agraf@suse.de>
| * | kvm: add device control APIScott Wood2013-04-261-0/+129
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, devices that are emulated inside KVM are configured in a hardcoded manner based on an assumption that any given architecture only has one way to do it. If there's any need to access device state, it is done through inflexible one-purpose-only IOCTLs (e.g. KVM_GET/SET_LAPIC). Defining new IOCTLs for every little thing is cumbersome and depletes a limited numberspace. This API provides a mechanism to instantiate a device of a certain type, returning an ID that can be used to set/get attributes of the device. Attributes may include configuration parameters (e.g. register base address), device state, operational commands, etc. It is similar to the ONE_REG API, except that it acts on devices rather than vcpus. Both device types and individual attributes can be tested without having to create the device or get/set the attribute, without the need for separately managing enumerated capabilities. Signed-off-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Alexander Graf <agraf@suse.de>
| * | KVM: Move irqfd resample cap handling to generic codeAlexander Graf2013-04-261-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | Now that we have most irqfd code completely platform agnostic, let's move irqfd's resample capability return to generic code as well. Signed-off-by: Alexander Graf <agraf@suse.de> Acked-by: Michael S. Tsirkin <mst@redhat.com>
| * | KVM: Move irq routing to generic codeAlexander Graf2013-04-261-0/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | The IRQ routing set ioctl lives in the hacky device assignment code inside of KVM today. This is definitely the wrong place for it. Move it to the much more natural kvm_main.c. Signed-off-by: Alexander Graf <agraf@suse.de> Acked-by: Michael S. Tsirkin <mst@redhat.com>
| * | KVM: Introduce CONFIG_HAVE_KVM_IRQ_ROUTINGAlexander Graf2013-04-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Quite a bit of code in KVM has been conditionalized on availability of IOAPIC emulation. However, most of it is generically applicable to platforms that don't have an IOPIC, but a different type of irq chip. Make code that only relies on IRQ routing, not an APIC itself, on CONFIG_HAVE_KVM_IRQ_ROUTING, so that we can reuse it later. Signed-off-by: Alexander Graf <agraf@suse.de> Acked-by: Michael S. Tsirkin <mst@redhat.com>
| * | KVM: VMX: Add the deliver posted interrupt algorithmYang Zhang2013-04-161-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | Only deliver the posted interrupt when target vcpu is running and there is no previous interrupt pending in pir. Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: Call common update function when ioapic entry changed.Yang Zhang2013-04-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Both TMR and EOI exit bitmap need to be updated when ioapic changed or vcpu's id/ldr/dfr changed. So use common function instead eoi exit bitmap specific function. Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: Let ioapic know the irq line statusYang Zhang2013-04-151-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | Userspace may deliver RTC interrupt without query the status. So we want to track RTC EOI for this case. Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com> Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: Move kvm_spurious_fault to x86.cGeoff Levand2013-04-081-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The routine kvm_spurious_fault() is an x86 specific routine, so move it from virt/kvm/kvm_main.c to arch/x86/kvm/x86.c. Fixes this sparse warning when building on arm64: virt/kvm/kvm_main.c:warning: symbol 'kvm_spurious_fault' was not declared. Should it be static? Signed-off-by: Geoff Levand <geoff@infradead.org> Signed-off-by: Gleb Natapov <gleb@redhat.com>
| * | KVM: Make local routines staticGeoff Levand2013-04-081-4/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The routines get_user_page_nowait(), kvm_io_bus_sort_cmp(), kvm_io_bus_insert_dev() and kvm_io_bus_get_first_dev() are only referenced within kvm_main.c, so give them static linkage. Fixes sparse warnings like these: virt/kvm/kvm_main.c: warning: symbol 'get_user_page_nowait' was not declared. Should it be static? Signed-off-by: Geoff Levand <geoff@infradead.org> Signed-off-by: Gleb Natapov <gleb@redhat.com>
| * | kvm: Iterate over only vcpus that are preemptedRaghavendra K T2013-03-111-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This helps in filtering out the eligible candidates further and thus potentially helps in quickly allowing preempted lockholders to run. Note that if a vcpu was spinning during preemption we filter them by checking whether they are preempted due to pause loop exit. Reviewed-by: Chegu Vinod <chegu_vinod@hp.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
| * | kvm: Record the preemption status of vcpus using preempt notifiersRaghavendra K T2013-03-111-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Note that we mark as preempted only when vcpu's task state was Running during preemption. Thanks Jiannan, Avi for preemption notifier ideas. Thanks Gleb, PeterZ for their precious suggestions. Thanks Srikar for an idea on avoiding rcu lock while checking task state that improved overcommit numbers. Reviewed-by: Chegu Vinod <chegu_vinod@hp.com> Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
| * | KVM: Initialize irqfd from kvm_init().Cornelia Huck2013-03-051-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, eventfd introduces module_init/module_exit functions to initialize/cleanup the irqfd workqueue. This only works, however, if no other module_init/module_exit functions are built into the same module. Let's just move the initialization and cleanup to kvm_init and kvm_exit. This way, it is also clearer where kvm startup may fail. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: set_memory_region: Refactor commit_memory_region()Takuya Yoshikawa2013-03-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch makes the parameter old a const pointer to the old memory slot and adds a new parameter named change to know the change being requested: the former is for removing extra copying and the latter is for cleaning up the code. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: set_memory_region: Refactor prepare_memory_region()Takuya Yoshikawa2013-03-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch drops the parameter old, a copy of the old memory slot, and adds a new parameter named change to know the change being requested. This not only cleans up the code but also removes extra copying of the memory slot structure. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: set_memory_region: Make kvm_mr_change available to arch codeTakuya Yoshikawa2013-03-041-18/+0
| | | | | | | | | | | | | | | | | | | | | This will be used for cleaning up prepare/commit_memory_region() later. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: set_memory_region: Drop user_alloc from set_memory_region()Takuya Yoshikawa2013-03-041-11/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | Except ia64's stale code, KVM_SET_MEMORY_REGION support, this is only used for sanity checks in __kvm_set_memory_region() which can easily be changed to use slot id instead. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
| * | KVM: set_memory_region: Drop user_alloc from prepare/commit_memory_region()Takuya Yoshikawa2013-03-041-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | X86 does not use this any more. The remaining user, s390's !user_alloc check, can be simply removed since KVM_SET_MEMORY_REGION ioctl is no longer supported. Note: fixed powerpc's indentations with spaces to suppress checkpatch errors. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* / KVM: Allow cross page reads and writes from cached translations.Andrew Honig2013-04-071-10/+37
|/ | | | | | | | | | | | | This patch adds support for kvm_gfn_to_hva_cache_init functions for reads and writes that will cross a page. If the range falls within the same memslot, then this will be a fast operation. If the range is split between two memslots, then the slower kvm_read_guest and kvm_write_guest are used. Tested: Test against kvm_clock unit tests. Signed-off-by: Andrew Honig <ahonig@google.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: Remove user_alloc from struct kvm_memory_slotTakuya Yoshikawa2013-02-111-1/+0
| | | | | | | | | | | | | | | | | | | This field was needed to differentiate memory slots created by the new API, KVM_SET_USER_MEMORY_REGION, from those by the old equivalent, KVM_SET_MEMORY_REGION, whose support was dropped long before: commit b74a07beed0e64bfba413dcb70dd6749c57f43dc KVM: Remove kernel-allocated memory regions Although we also have private memory slots to which KVM allocates memory with vm_mmap(), !user_alloc slots in other words, the slot id should be enough for differentiating them. Note: corresponding function parameters will be removed later. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: set_memory_region: Disallow changing read-only attribute laterTakuya Yoshikawa2013-02-041-23/+12
| | | | | | | | | | | | | | | | | | As Xiao pointed out, there are a few problems with it: - kvm_arch_commit_memory_region() write protects the memory slot only for GET_DIRTY_LOG when modifying the flags. - FNAME(sync_page) uses the old spte value to set a new one without checking KVM_MEM_READONLY flag. Since we flush all shadow pages when creating a new slot, the simplest fix is to disallow such problematic flag changes: this is safe because no one is doing such things. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Cc: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Cc: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: set_memory_region: Identify the requested change explicitlyTakuya Yoshikawa2013-02-041-20/+44
| | | | | | | | | | | | | | | | | | | | | KVM_SET_USER_MEMORY_REGION forces __kvm_set_memory_region() to identify what kind of change is being requested by checking the arguments. The current code does this checking at various points in code and each condition being used there is not easy to understand at first glance. This patch consolidates these checks and introduces an enum to name the possible changes to clean up the code. Although this does not introduce any functional changes, there is one change which optimizes the code a bit: if we have nothing to change, the new code returns 0 immediately. Note that the return value for this case cannot be changed since QEMU relies on it: we noticed this when we changed it to -EINVAL and got a section mismatch error at the final stage of live migration. Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* kvm: Handle yield_to failure return code for potential undercommit caseRaghavendra K T2013-01-291-10/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | yield_to returns -ESRCH, When source and target of yield_to run queue length is one. When we see three successive failures of yield_to we assume we are in potential undercommit case and abort from PLE handler. The assumption is backed by low probability of wrong decision for even worst case scenarios such as average runqueue length between 1 and 2. More detail on rationale behind using three tries: if p is the probability of finding rq length one on a particular cpu, and if we do n tries, then probability of exiting ple handler is: p^(n+1) [ because we would have come across one source with rq length 1 and n target cpu rqs with length 1 ] so num tries: probability of aborting ple handler (1.5x overcommit) 1 1/4 2 1/8 3 1/16 We can increase this probability with more tries, but the problem is the overhead. Also, If we have tried three times that means we would have iterated over 3 good eligible vcpus along with many non-eligible candidates. In worst case if we iterate all the vcpus, we reduce 1x performance and overcommit performance get hit. note that we do not update last boosted vcpu in failure cases. Thank Avi for raising question on aborting after first fail from yield_to. Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Tested-by: Chegu Vinod <chegu_vinod@hp.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* x86, apicv: add virtual interrupt delivery supportYang Zhang2013-01-291-0/+5
| | | | | | | | | | | | | | | | | | | Virtual interrupt delivery avoids KVM to inject vAPIC interrupts manually, which is fully taken care of by the hardware. This needs some special awareness into existing interrupr injection path: - for pending interrupt, instead of direct injection, we may need update architecture specific indicators before resuming to guest. - A pending interrupt, which is masked by ISR, should be also considered in above update action, since hardware will decide when to inject it at right time. Current has_interrupt and get_interrupt only returns a valid vector from injection p.o.v. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Kevin Tian <kevin.tian@intel.com> Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* kvm: Force IOMMU remapping on memory slot read-only flag changesAlex Williamson2013-01-271-4/+24
| | | | | | | | | | | | Memory slot flags can be altered without changing other parameters of the slot. The read-only attribute is the only one the IOMMU cares about, so generate an un-map, re-map when this occurs. This also avoid unnecessarily re-mapping the slot when no IOMMU visible changes are made. Reviewed-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: set_memory_region: Remove unnecessary variable memslotTakuya Yoshikawa2013-01-171-6/+5
| | | | | | | | | | One such variable, slot, is enough for holding a pointer temporarily. We also remove another local variable named slot, which is limited in a block, since it is confusing to have the same name in this function. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: set_memory_region: Don't check for overlaps unless we create or move a slotTakuya Yoshikawa2013-01-171-8/+10
| | | | | | | | | Don't need the check for deleting an existing slot or just modifiying the flags. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: set_memory_region: Don't jump to out_free unnecessarilyTakuya Yoshikawa2013-01-171-4/+3
| | | | | | | | | This makes the separation between the sanity checks and the rest of the code a bit clearer. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: Write protect the updated slot only when dirty logging is enabledTakuya Yoshikawa2013-01-141-1/+0
| | | | | | | | | | | | | | Calling kvm_mmu_slot_remove_write_access() for a deleted slot does nothing but search for non-existent mmu pages which have mappings to that deleted memory; this is safe but a waste of time. Since we want to make the function rmap based in a later patch, in a manner which makes it unsafe to be called for a deleted slot, we makes the caller see if the slot is non-zero and being dirty logged. Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: move the code that installs new slots array to a separate function.Gleb Natapov2012-12-241-8/+13
| | | | | | | Move repetitive code sequence to a separate function. Reviewed-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* kvm: Fix memory slot generation updatesAlex Williamson2012-12-231-4/+5
| | | | | | | | | | | | | Previous patch "kvm: Minor memory slot optimization" (b7f69c555ca43) overlooked the generation field of the memory slots. Re-using the original memory slots left us with with two slightly different memory slots with the same generation. To fix this, make update_memslots() take a new parameter to specify the last generation. This also makes generation management more explicit to avoid such problems in the future. Reported-by: Takuya Yoshikawa <yoshikawa_takuya_b1@lab.ntt.co.jp> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Gleb Natapov <gleb@redhat.com>
* KVM: struct kvm_memory_slot.id -> shortAlex Williamson2012-12-131-0/+2
| | | | | | | | | | We're currently offering a whopping 32 memory slots to user space, an int is a bit excessive for storing this. We would like to increase our memslots, but SHRT_MAX should be more than enough. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: struct kvm_memory_slot.user_alloc -> boolAlex Williamson2012-12-131-4/+4
| | | | | | | | | There's no need for this to be an int, it holds a boolean. Move to the end of the struct for alignment. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: Rename KVM_MEMORY_SLOTS -> KVM_USER_MEM_SLOTSAlex Williamson2012-12-131-4/+4
| | | | | | | | | | It's easy to confuse KVM_MEMORY_SLOTS and KVM_MEM_SLOTS_NUM. One is the user accessible slots and the other is user + private. Make this more obvious. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: Minor memory slot optimizationAlex Williamson2012-12-131-7/+14
| | | | | | | | | | | | If a slot is removed or moved in the guest physical address space, we first allocate and install a new slot array with the invalidated entry. The old array is then freed. We then proceed to allocate yet another slot array to install the permanent replacement. Re-use the original array when this occurs and avoid the extra kfree/kmalloc. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: Fix iommu map/unmap to handle memory slot movesAlex Williamson2012-12-131-8/+11
| | | | | | | | | | | | The iommu integration into memory slots expects memory slots to be added or removed and doesn't handle the move case. We can unmap slots from the iommu after we mark them invalid and map them before installing the final memslot array. Also re-order the kmemdup vs map so we don't leave iommu mappings if we get ENOMEM. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
* KVM: Check userspace_addr when modifying a memory slotAlex Williamson2012-12-131-1/+7
| | | | | | | | | | | | | The API documents that only flags and guest physical memory space can be modified on an existing slot, but we don't enforce that the userspace address cannot be modified. Instead we just ignore it. This means that a user may think they've successfully moved both the guest and user addresses, when in fact only the guest address changed. Check and error instead. Reviewed-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>