- 20 Oct, 2015 3 commits
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Arnd Bergmann authored
The vgic code on ARM is built for all configurations that enable KVM, but the parent_data field that it references is only present when CONFIG_IRQ_DOMAIN_HIERARCHY is set: virt/kvm/arm/vgic.c: In function 'kvm_vgic_map_phys_irq': virt/kvm/arm/vgic.c:1781:13: error: 'struct irq_data' has no member named 'parent_data' This flag is implied by the GIC driver, and indeed the VGIC code only makes sense if a GIC is present. This changes the CONFIG_KVM symbol to always select GIC, which avoids the issue. Fixes: 662d9715 ("arm/arm64: KVM: Kill CONFIG_KVM_ARM_{VGIC,TIMER}") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
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Pavel Fedin authored
Jump to correct label and free kvm_host_cpu_state Reviewed-by: Wei Huang <wei@redhat.com> Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
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Pavel Fedin authored
When lowering a level-triggered line from userspace, we forgot to lower the pending bit on the emulated CPU interface and we also did not re-compute the pending_on_cpu bitmap for the CPU affected by the change. Update vgic_update_irq_pending() to fix the two issues above and also raise a warning in vgic_quue_irq_to_lr if we encounter an interrupt pending on a CPU which is neither marked active nor pending. [ Commit text reworked completely - Christoffer ] Signed-off-by: Pavel Fedin <p.fedin@samsung.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
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- 25 Sep, 2015 4 commits
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David Hildenbrand authored
We observed some performance degradation on s390x with dynamic halt polling. Until we can provide a proper fix, let's enable halt_poll_ns as default only for supported architectures. Architectures are now free to set their own halt_poll_ns default value. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Paolo Bonzini authored
29ecd660 ("KVM: x86: avoid uninitialized variable warning", 2015-09-06) introduced a not-so-subtle problem, which probably escaped review because it was not part of the patch context. Before the patch, leaf was always equal to iterator.level. After, it is equal to iterator.level - 1 in the call to is_shadow_zero_bits_set, and when is_shadow_zero_bits_set does another "-1" the check on reserved bits becomes incorrect. Using "iterator.level" in the call fixes this call trace: WARNING: CPU: 2 PID: 17000 at arch/x86/kvm/mmu.c:3385 handle_mmio_page_fault.part.93+0x1a/0x20 [kvm]() Modules linked in: tun sha256_ssse3 sha256_generic drbg binfmt_misc ipv6 vfat fat fuse dm_crypt dm_mod kvm_amd kvm crc32_pclmul aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd fam15h_power amd64_edac_mod k10temp edac_core amdkfd amd_iommu_v2 radeon acpi_cpufreq [...] Call Trace: dump_stack+0x4e/0x84 warn_slowpath_common+0x95/0xe0 warn_slowpath_null+0x1a/0x20 handle_mmio_page_fault.part.93+0x1a/0x20 [kvm] tdp_page_fault+0x231/0x290 [kvm] ? emulator_pio_in_out+0x6e/0xf0 [kvm] kvm_mmu_page_fault+0x36/0x240 [kvm] ? svm_set_cr0+0x95/0xc0 [kvm_amd] pf_interception+0xde/0x1d0 [kvm_amd] handle_exit+0x181/0xa70 [kvm_amd] ? kvm_arch_vcpu_ioctl_run+0x68b/0x1730 [kvm] kvm_arch_vcpu_ioctl_run+0x6f6/0x1730 [kvm] ? kvm_arch_vcpu_ioctl_run+0x68b/0x1730 [kvm] ? preempt_count_sub+0x9b/0xf0 ? mutex_lock_killable_nested+0x26f/0x490 ? preempt_count_sub+0x9b/0xf0 kvm_vcpu_ioctl+0x358/0x710 [kvm] ? __fget+0x5/0x210 ? __fget+0x101/0x210 do_vfs_ioctl+0x2f4/0x560 ? __fget_light+0x29/0x90 SyS_ioctl+0x4c/0x90 entry_SYSCALL_64_fastpath+0x16/0x73 ---[ end trace 37901c8686d84de6 ]--- Reported-by: Borislav Petkov <bp@alien8.de> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Paolo Bonzini authored
Intel CPUID on AMD host or vice versa is a weird case, but it can happen. Handle it by checking the host CPU vendor instead of the guest's in reset_tdp_shadow_zero_bits_mask. For speed, the check uses the fact that Intel EPT has an X (executable) bit while AMD NPT has NX. Reported-by: Borislav Petkov <bp@alien8.de> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Paolo Bonzini authored
kvm_set_cr0 may want to call kvm_zap_gfn_range and thus access the memslots array (SRCU protected). Using a mini SRCU critical section is ugly, and adding it to kvm_arch_vcpu_create doesn't work because the VMX vcpu_create callback calls synchronize_srcu. Fixes this lockdep splat: =============================== [ INFO: suspicious RCU usage. ] 4.3.0-rc1+ #1 Not tainted ------------------------------- include/linux/kvm_host.h:488 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 1, debug_locks = 0 1 lock held by qemu-system-i38/17000: #0: (&(&kvm->mmu_lock)->rlock){+.+...}, at: kvm_zap_gfn_range+0x24/0x1a0 [kvm] [...] Call Trace: dump_stack+0x4e/0x84 lockdep_rcu_suspicious+0xfd/0x130 kvm_zap_gfn_range+0x188/0x1a0 [kvm] kvm_set_cr0+0xde/0x1e0 [kvm] init_vmcb+0x760/0xad0 [kvm_amd] svm_create_vcpu+0x197/0x250 [kvm_amd] kvm_arch_vcpu_create+0x47/0x70 [kvm] kvm_vm_ioctl+0x302/0x7e0 [kvm] ? __lock_is_held+0x51/0x70 ? __fget+0x101/0x210 do_vfs_ioctl+0x2f4/0x560 ? __fget_light+0x29/0x90 SyS_ioctl+0x4c/0x90 entry_SYSCALL_64_fastpath+0x16/0x73 Reported-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- 22 Sep, 2015 1 commit
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Paolo Bonzini authored
Merge branch 'kvm-ppc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-master
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- 21 Sep, 2015 1 commit
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Paolo Bonzini authored
These have roughly the same purpose as the SMRR, which we do not need to implement in KVM. However, Linux accesses MSR_K8_TSEG_ADDR at boot, which causes problems when running a Xen dom0 under KVM. Just return 0, meaning that processor protection of SMRAM is not in effect. Reported-by: M A Young <m.a.young@durham.ac.uk> Cc: stable@vger.kernel.org Acked-by: Borislav Petkov <bp@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- 20 Sep, 2015 3 commits
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Thomas Huth authored
Access to the kvm->buses (like with the kvm_io_bus_read() and -write() functions) has to be protected via the kvm->srcu lock. The kvmppc_h_logical_ci_load() and -store() functions are missing this lock so far, so let's add it there, too. This fixes the problem that the kernel reports "suspicious RCU usage" when lock debugging is enabled. Cc: stable@vger.kernel.org # v4.1+ Fixes: 99342cf8Signed-off-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
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Gautham R. Shenoy authored
In guest_exit_cont we call kvmhv_commence_exit which expects the trap number as the argument. However r3 doesn't contain the trap number at this point and as a result we would be calling the function with a spurious trap number. Fix this by copying r12 into r3 before calling kvmhv_commence_exit as r12 contains the trap number. Cc: stable@vger.kernel.org # v4.1+ Fixes: eddb60fbSigned-off-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
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Paul Mackerras authored
This fixes a bug which results in stale vcore pointers being left in the per-cpu preempted vcore lists when a VM is destroyed. The result of the stale vcore pointers is usually either a crash or a lockup inside collect_piggybacks() when another VM is run. A typical lockup message looks like: [ 472.161074] NMI watchdog: BUG: soft lockup - CPU#24 stuck for 22s! [qemu-system-ppc:7039] [ 472.161204] Modules linked in: kvm_hv kvm_pr kvm xt_CHECKSUM ipt_MASQUERADE nf_nat_masquerade_ipv4 tun ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw ses enclosure shpchp rtc_opal i2c_opal powernv_rng binfmt_misc dm_service_time scsi_dh_alua radeon i2c_algo_bit drm_kms_helper ttm drm tg3 ptp pps_core cxgb3 ipr i2c_core mdio dm_multipath [last unloaded: kvm_hv] [ 472.162111] CPU: 24 PID: 7039 Comm: qemu-system-ppc Not tainted 4.2.0-kvm+ #49 [ 472.162187] task: c000001e38512750 ti: c000001e41bfc000 task.ti: c000001e41bfc000 [ 472.162262] NIP: c00000000096b094 LR: c00000000096b08c CTR: c000000000111130 [ 472.162337] REGS: c000001e41bff520 TRAP: 0901 Not tainted (4.2.0-kvm+) [ 472.162399] MSR: 9000000100009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 24848844 XER: 00000000 [ 472.162588] CFAR: c00000000096b0ac SOFTE: 1 GPR00: c000000000111170 c000001e41bff7a0 c00000000127df00 0000000000000001 GPR04: 0000000000000003 0000000000000001 0000000000000000 0000000000874821 GPR08: c000001e41bff8e0 0000000000000001 0000000000000000 d00000000efde740 GPR12: c000000000111130 c00000000fdae400 [ 472.163053] NIP [c00000000096b094] _raw_spin_lock_irqsave+0xa4/0x130 [ 472.163117] LR [c00000000096b08c] _raw_spin_lock_irqsave+0x9c/0x130 [ 472.163179] Call Trace: [ 472.163206] [c000001e41bff7a0] [c000001e41bff7f0] 0xc000001e41bff7f0 (unreliable) [ 472.163295] [c000001e41bff7e0] [c000000000111170] __wake_up+0x40/0x90 [ 472.163375] [c000001e41bff830] [d00000000efd6fc0] kvmppc_run_core+0x1240/0x1950 [kvm_hv] [ 472.163465] [c000001e41bffa30] [d00000000efd8510] kvmppc_vcpu_run_hv+0x5a0/0xd90 [kvm_hv] [ 472.163559] [c000001e41bffb70] [d00000000e9318a4] kvmppc_vcpu_run+0x44/0x60 [kvm] [ 472.163653] [c000001e41bffba0] [d00000000e92e674] kvm_arch_vcpu_ioctl_run+0x64/0x170 [kvm] [ 472.163745] [c000001e41bffbe0] [d00000000e9263a8] kvm_vcpu_ioctl+0x538/0x7b0 [kvm] [ 472.163834] [c000001e41bffd40] [c0000000002d0f50] do_vfs_ioctl+0x480/0x7c0 [ 472.163910] [c000001e41bffde0] [c0000000002d1364] SyS_ioctl+0xd4/0xf0 [ 472.163986] [c000001e41bffe30] [c000000000009260] system_call+0x38/0xd0 [ 472.164060] Instruction dump: [ 472.164098] ebc1fff0 ebe1fff8 7c0803a6 4e800020 60000000 60000000 60420000 8bad02e2 [ 472.164224] 7fc3f378 4b6a57c1 60000000 7c210b78 <e92d0000> 89290009 792affe3 40820070 The bug is that kvmppc_run_vcpu does not correctly handle the case where a vcpu task receives a signal while its guest vcpu is executing in the guest as a result of being piggy-backed onto the execution of another vcore. In that case we need to wait for the vcpu to finish executing inside the guest, and then remove this vcore from the preempted vcores list. That way, we avoid leaving this vcpu's vcore on the preempted vcores list when the vcpu gets interrupted. Fixes: ec257165Reported-by: Thomas Huth <thuth@redhat.com> Tested-by: Thomas Huth <thuth@redhat.com> Signed-off-by: Paul Mackerras <paulus@samba.org>
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- 18 Sep, 2015 2 commits
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Igor Mammedov authored
When INIT/SIPI sequence is sent to VCPU which before that was in use by OS, VMRUN might fail with: KVM: entry failed, hardware error 0xffffffff EAX=00000000 EBX=00000000 ECX=00000000 EDX=000006d3 ESI=00000000 EDI=00000000 EBP=00000000 ESP=00000000 EIP=00000000 EFL=00000002 [-------] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES =0000 00000000 0000ffff 00009300 CS =9a00 0009a000 0000ffff 00009a00 [...] CR0=60000010 CR2=b6f3e000 CR3=01942000 CR4=000007e0 [...] EFER=0000000000000000 with corresponding SVM error: KVM: FAILED VMRUN WITH VMCB: [...] cpl: 0 efer: 0000000000001000 cr0: 0000000080010010 cr2: 00007fd7fe85bf90 cr3: 0000000187d0c000 cr4: 0000000000000020 [...] What happens is that VCPU state right after offlinig: CR0: 0x80050033 EFER: 0xd01 CR4: 0x7e0 -> long mode with CR3 pointing to longmode page tables and when VCPU gets INIT/SIPI following transition happens CR0: 0 -> 0x60000010 EFER: 0x0 CR4: 0x7e0 -> paging disabled with stale CR3 However SVM under the hood puts VCPU in Paged Real Mode* which effectively translates CR0 0x60000010 -> 80010010 after svm_vcpu_reset() -> init_vmcb() -> kvm_set_cr0() -> svm_set_cr0() but from kvm_set_cr0() perspective CR0: 0 -> 0x60000010 only caching bits are changed and commit d81135a5 ("KVM: x86: do not reset mmu if CR0.CD and CR0.NW are changed")' regressed svm_vcpu_reset() which relied on MMU being reset. As result VMRUN after svm_vcpu_reset() tries to run VCPU in Paged Real Mode with stale MMU context (longmode page tables), which causes some AMD CPUs** to bail out with VMEXIT_INVALID. Fix issue by unconditionally resetting MMU context at init_vmcb() time. * AMD64 Architecture Programmerâ€
™ s Manual, Volume 2: System Programming, rev: 3.25 15.19 Paged Real Mode ** Opteron 1216 Signed-off-by: Igor Mammedov <imammedo@redhat.com> Fixes: d81135a5 Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> -
Dominik Dingel authored
Commit 2ee507c4 ("sched: Add function single_task_running to let a task check if it is the only task running on a cpu") referenced the current runqueue with the smp_processor_id. When CONFIG_DEBUG_PREEMPT is enabled, that is only allowed if preemption is disabled or the currrent task is bound to the local cpu (e.g. kernel worker). With commit f7819512 ("kvm: add halt_poll_ns module parameter") KVM calls single_task_running. If CONFIG_DEBUG_PREEMPT is enabled that generates a lot of kernel messages. To avoid adding preemption in that cases, as it would limit the usefulness, we change single_task_running to access directly the cpu local runqueue. Cc: Tim Chen <tim.c.chen@linux.intel.com> Suggested-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: <stable@vger.kernel.org> Fixes: 2ee507c4Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- 17 Sep, 2015 5 commits
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Paolo Bonzini authored
Merge tag 'kvm-arm-for-4.3-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master Second set of KVM/ARM changes for 4.3-rc2 - Workaround for a Cortex-A57 erratum - Bug fix for the debugging infrastructure - Fix for 32bit guests with more than 4GB of address space on a 32bit host - A number of fixes for the (unusual) case when we don't use the in-kernel GIC emulation - Removal of ThumbEE handling on arm64, since these have been dropped from the architecture before anyone actually ever built a CPU - Remove the KVM_ARM_MAX_VCPUS limitation which has become fairly pointless
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Ming Lei authored
This patch removes config option of KVM_ARM_MAX_VCPUS, and like other ARCHs, just choose the maximum allowed value from hardware, and follows the reasons: 1) from distribution view, the option has to be defined as the max allowed value because it need to meet all kinds of virtulization applications and need to support most of SoCs; 2) using a bigger value doesn't introduce extra memory consumption, and the help text in Kconfig isn't accurate because kvm_vpu structure isn't allocated until request of creating VCPU is sent from QEMU; 3) the main effect is that the field of vcpus[] in 'struct kvm' becomes a bit bigger(sizeof(void *) per vcpu) and need more cache lines to hold the structure, but 'struct kvm' is one generic struct, and it has worked well on other ARCHs already in this way. Also, the world switch frequecy is often low, for example, it is ~2000 when running kernel building load in VM from APM xgene KVM host, so the effect is very small, and the difference can't be observed in my test at all. Cc: Dann Frazier <dann.frazier@canonical.com> Signed-off-by: Ming Lei <ming.lei@canonical.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Will Deacon authored
Although the ThumbEE registers and traps were present in earlier versions of the v8 architecture, it was retrospectively removed and so we can do the same. Whilst this breaks migrating a guest started on a previous version of the kernel, it is much better to kill these (non existent) registers as soon as possible. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> [maz: added commend about migration] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
When running a guest with the architected timer disabled (with QEMU and the kernel_irqchip=off option, for example), it is important to make sure the timer gets turned off. Otherwise, the guest may try to enable it anyway, leading to a screaming HW interrupt. The fix is to unconditionally turn off the virtual timer on guest exit. Cc: stable@vger.kernel.org Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
When running a guest with the architected timer disabled (with QEMU and the kernel_irqchip=off option, for example), it is important to make sure the timer gets turned off. Otherwise, the guest may try to enable it anyway, leading to a screaming HW interrupt. The fix is to unconditionally turn off the virtual timer on guest exit. Cc: stable@vger.kernel.org Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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- 16 Sep, 2015 6 commits
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Pavel Fedin authored
Until b26e5fda ("arm/arm64: KVM: introduce per-VM ops"), kvm_vgic_map_resources() used to include a check on irqchip_in_kernel(), and vgic_v2_map_resources() still has it. But now vm_ops are not initialized until we call kvm_vgic_create(). Therefore kvm_vgic_map_resources() can being called without a VGIC, and we die because vm_ops.map_resources is NULL. Fixing this restores QEMU's kernel-irqchip=off option to a working state, allowing to use GIC emulation in userspace. Fixes: b26e5fda ("arm/arm64: KVM: introduce per-VM ops") Cc: stable@vger.kernel.org Signed-off-by: Pavel Fedin <p.fedin@samsung.com> [maz: reworked commit message] Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Jason J. Herne authored
The offending commit accidentally replaces an atomic_clear with an atomic_or instead of an atomic_andnot in kvm_s390_vcpu_request_handled. The symptom is that kvm guests on s390 hang on startup. This patch simply replaces the incorrect atomic_or with atomic_andnot Fixes: 805de8f4 (atomic: Replace atomic_{set,clear}_mask() usage) Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Marek Majtyka authored
A critical bug has been found in device memory stage1 translation for VMs with more then 4GB of address space. Once vm_pgoff size is smaller then pa (which is true for LPAE case, u32 and u64 respectively) some more significant bits of pa may be lost as a shift operation is performed on u32 and later cast onto u64. Example: vm_pgoff(u32)=0x00210030, PAGE_SHIFT=12 expected pa(u64): 0x0000002010030000 produced pa(u64): 0x0000000010030000 The fix is to change the order of operations (casting first onto phys_addr_t and then shifting). Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> [maz: fixed changelog and patch formatting] Cc: stable@vger.kernel.org Signed-off-by: Marek Majtyka <marek.majtyka@tieto.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Marc Zyngier authored
When setting the debug register from userspace, make sure that copy_from_user() is called with its parameters in the expected order. It otherwise doesn't do what you think. Fixes: 84e690bf ("KVM: arm64: introduce vcpu->arch.debug_ptr") Reported-by: Peter Maydell <peter.maydell@linaro.org> Cc: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Wanpeng Li authored
Reference SDM 28.1: The current VPID is 0000H in the following situations: - Outside VMX operation. (This includes operation in system-management mode under the default treatment of SMIs and SMM with VMX operation; see Section 34.14.) - In VMX root operation. - In VMX non-root operation when the “enable VPID” VM-execution control is 0. The VPID should never be 0000H in non-root operation when "enable VPID" VM-execution control is 1. However, commit 34a1cd60 ("kvm: x86: vmx: move some vmx setting from vmx_init() to hardware_setup()") remove the codes which reserve 0000H for VMX root operation. This patch fix it by again reserving 0000H for VMX root operation. Cc: stable@vger.kernel.org # 3.19+ Fixes: 34a1cd60Reported-by: Wincy Van <fanwenyi0529@gmail.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Paolo Bonzini authored
This new statistic can help diagnosing VCPUs that, for any reason, trigger bad behavior of halt_poll_ns autotuning. For example, say halt_poll_ns = 480000, and wakeups are spaced exactly like 479us, 481us, 479us, 481us. Then KVM always fails polling and wastes 10+20+40+80+160+320+480 = 1110 microseconds out of every 479+481+479+481+479+481+479 = 3359 microseconds. The VCPU then is consuming about 30% more CPU than it would use without polling. This would show as an abnormally high number of attempted polling compared to the successful polls. Acked-by: Christian Borntraeger <borntraeger@de.ibm.com< Reviewed-by: David Matlack <dmatlack@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- 15 Sep, 2015 4 commits
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Jason Wang authored
Currently, if we had a zero length mmio eventfd assigned on KVM_MMIO_BUS. It will never be found by kvm_io_bus_cmp() since it always compares the kvm_io_range() with the length that guest wrote. This will cause e.g for vhost, kick will be trapped by qemu userspace instead of vhost. Fixing this by using zero length if an iodevice is zero length. Cc: stable@vger.kernel.org Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Jason Wang authored
We register wildcard mmio eventfd on two buses, once for KVM_MMIO_BUS and once on KVM_FAST_MMIO_BUS but with a single iodev instance. This will lead to an issue: kvm_io_bus_destroy() knows nothing about the devices on two buses pointing to a single dev. Which will lead to double free[1] during exit. Fix this by allocating two instances of iodevs then registering one on KVM_MMIO_BUS and another on KVM_FAST_MMIO_BUS. CPU: 1 PID: 2894 Comm: qemu-system-x86 Not tainted 3.19.0-26-generic #28-Ubuntu Hardware name: LENOVO 2356BG6/2356BG6, BIOS G7ET96WW (2.56 ) 09/12/2013 task: ffff88009ae0c4b0 ti: ffff88020e7f0000 task.ti: ffff88020e7f0000 RIP: 0010:[<ffffffffc07e25d8>] [<ffffffffc07e25d8>] ioeventfd_release+0x28/0x60 [kvm] RSP: 0018:ffff88020e7f3bc8 EFLAGS: 00010292 RAX: dead000000200200 RBX: ffff8801ec19c900 RCX: 000000018200016d RDX: ffff8801ec19cf80 RSI: ffffea0008bf1d40 RDI: ffff8801ec19c900 RBP: ffff88020e7f3bd8 R08: 000000002fc75a01 R09: 000000018200016d R10: ffffffffc07df6ae R11: ffff88022fc75a98 R12: ffff88021e7cc000 R13: ffff88021e7cca48 R14: ffff88021e7cca50 R15: ffff8801ec19c880 FS: 00007fc1ee3e6700(0000) GS:ffff88023e240000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f8f389d8000 CR3: 000000023dc13000 CR4: 00000000001427e0 Stack: ffff88021e7cc000 0000000000000000 ffff88020e7f3be8 ffffffffc07e2622 ffff88020e7f3c38 ffffffffc07df69a ffff880232524160 ffff88020e792d80 0000000000000000 ffff880219b78c00 0000000000000008 ffff8802321686a8 Call Trace: [<ffffffffc07e2622>] ioeventfd_destructor+0x12/0x20 [kvm] [<ffffffffc07df69a>] kvm_put_kvm+0xca/0x210 [kvm] [<ffffffffc07df818>] kvm_vcpu_release+0x18/0x20 [kvm] [<ffffffff811f69f7>] __fput+0xe7/0x250 [<ffffffff811f6bae>] ____fput+0xe/0x10 [<ffffffff81093f04>] task_work_run+0xd4/0xf0 [<ffffffff81079358>] do_exit+0x368/0xa50 [<ffffffff81082c8f>] ? recalc_sigpending+0x1f/0x60 [<ffffffff81079ad5>] do_group_exit+0x45/0xb0 [<ffffffff81085c71>] get_signal+0x291/0x750 [<ffffffff810144d8>] do_signal+0x28/0xab0 [<ffffffff810f3a3b>] ? do_futex+0xdb/0x5d0 [<ffffffff810b7028>] ? __wake_up_locked_key+0x18/0x20 [<ffffffff810f3fa6>] ? SyS_futex+0x76/0x170 [<ffffffff81014fc9>] do_notify_resume+0x69/0xb0 [<ffffffff817cb9af>] int_signal+0x12/0x17 Code: 5d c3 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb 48 83 ec 08 48 8b 7f 20 e8 06 d6 a5 c0 48 8b 43 08 48 8b 13 48 89 df 48 89 42 08 <48> 89 10 48 b8 00 01 10 00 00 RIP [<ffffffffc07e25d8>] ioeventfd_release+0x28/0x60 [kvm] RSP <ffff88020e7f3bc8> Cc: stable@vger.kernel.org Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Jason Wang authored
This patch factors out core eventfd assign/deassign logic and leaves the argument checking and bus index selection to callers. Cc: stable@vger.kernel.org Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Jason Wang authored
We only want zero length mmio eventfd to be registered on KVM_FAST_MMIO_BUS. So check this explicitly when arg->len is zero to make sure this. Cc: stable@vger.kernel.org Cc: Gleb Natapov <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- 14 Sep, 2015 4 commits
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Wei Yang authored
After 'commit 0b8ba4a2 ("KVM: fix checkpatch.pl errors in kvm/coalesced_mmio.h")', the declaration of the two function will exceed 80 characters. This patch reduces the TAPs to make each line in 80 characters. Signed-off-by: Wei Yang <weiyang@linux.vnet.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Will Deacon authored
When restoring the system register state for an AArch32 guest at EL2, writes to DACR32_EL2 may not be correctly synchronised by Cortex-A57, which can lead to the guest effectively running with junk in the DACR and running into unexpected domain faults. This patch works around the issue by re-ordering our restoration of the AArch32 register aliases so that they happen before the AArch64 system registers. Ensuring that the registers are restored in this order guarantees that they will be correctly synchronised by the core. Cc: <stable@vger.kernel.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
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Paolo Bonzini authored
Merge tag 'kvm-arm-for-4.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master KVM/ARM changes for 4.3-rc2 - Fix timer interrupt injection after the rework that went in during the merge window - Reset the timer to zero on reboot - Make sure the TCR_EL2 RES1 bits are really set to 1 - Fix a PSCI affinity bug for non-existing vcpus
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Wanpeng Li authored
If there is already some polling ongoing, it's impossible to disable the polling, since as soon as somebody sets halt_poll_ns to 0, polling will never stop, as grow and shrink are only handled if halt_poll_ns is != 0. This patch fix it by reset vcpu->halt_poll_ns in order to stop polling when polling is disabled. Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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- 12 Sep, 2015 7 commits
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Linus Torvalds authored
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git://git.kernel.org/pub/scm/linux/kernel/git/jesper/crisLinus Torvalds authored
Pull CRIS updates from Jesper Nilsson: "Mostly removal of old cruft of which we can use a generic version, or fixes for code not commonly run in the cris port, but also additions to enable some good debug" * tag 'cris-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jesper/cris: (25 commits) CRISv10: delete unused lib/dmacopy.c CRISv10: delete unused lib/old_checksum.c CRIS: fix switch_mm() lockdep splat CRISv32: enable LOCKDEP_SUPPORT CRIS: add STACKTRACE_SUPPORT CRISv32: annotate irq enable in idle loop CRISv32: add support for irqflags tracing CRIS: UAPI: use generic types.h CRIS: UAPI: use generic shmbuf.h CRIS: UAPI: use generic msgbuf.h CRIS: UAPI: use generic socket.h CRIS: UAPI: use generic sembuf.h CRIS: UAPI: use generic sockios.h CRIS: UAPI: use generic auxvec.h CRIS: UAPI: use generic headers via Kbuild CRIS: UAPI: fix elf.h export CRIS: don't make asm/elf.h depend on asm/user.h CRIS: UAPI: fix ptrace.h CRISv32: Squash compile warnings for axisflashmap CRISv32: Add GPIO driver to the default configs ...
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Linus Torvalds authored
rq_data_dir() returns either READ or WRITE (0 == READ, 1 == WRITE), not a boolean value. Now, admittedly the "!= 0" doesn't really change the value (0 stays as zero, 1 stays as one), but it's not only redundant, it confuses gcc, and causes gcc to warn about the construct switch (rq_data_dir(req)) { case READ: ... case WRITE: ... that we have in a few drivers. Now, the gcc warning is silly and stupid (it seems to warn not about the switch value having a different type from the case statements, but about _any_ boolean switch value), but in this case the code itself is silly and stupid too, so let's just change it, and get rid of warnings like this: drivers/block/hd.c: In function ‘hd_request’: drivers/block/hd.c:630:11: warning: switch condition has boolean value [-Wswitch-bool] switch (rq_data_dir(req)) { The odd '!= 0' came in when "cmd_flags" got turned into a "u64" in commit 5953316d ("block: make rq->cmd_flags be 64-bit") and is presumably because the old code (that just did a logical 'and' with 1) would then end up making the type of rq_data_dir() be u64 too. But if we want to retain the old regular integer type, let's just cast the result to 'int' rather than use that rather odd '!= 0'. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
Fix up the writeback plugging introduced in commit d353d758 ("writeback: plug writeback at a high level") that then caused problems due to the unplug happening with a spinlock held. * writeback-plugging: writeback: plug writeback in wb_writeback() and writeback_inodes_wb() Revert "writeback: plug writeback at a high level"
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Linus Torvalds authored
We had to revert the pluggin in writeback_sb_inodes() because the wb->list_lock is held, but we could easily plug at a higher level before taking that lock, and unplug after releasing it. This does that. Chris will run performance numbers, just to verify that this approach is comparable to the alternative (we could just drop and re-take the lock around the blk_finish_plug() rather than these two commits. I'd have preferred waiting for actual performance numbers before picking one approach over the other, but I don't want to release rc1 with the known "sleeping function called from invalid context" issue, so I'll pick this cleanup version for now. But if the numbers show that we really want to plug just at the writeback_sb_inodes() level, and we should just play ugly games with the spinlock, we'll switch to that. Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
I didn't notice this when merging the thermal code from Zhang, but his merge (commit 5a924a07: "Merge branches 'thermal-core' and 'thermal-intel' of .git into next") of the thermal-core and thermal-intel branches was wrong. In thermal-core, commit 17e8351a ("thermal: consistently use int for temperatures") converted the thermal layer to use "int" for temperatures. But in parallel, in the thermal-intel branch commit d0a12625 ("thermal: Add Intel PCH thermal driver") added support for the intel PCH thermal sensor using the old interfaces that used "unsigned long" pointers. This resulted in warnings like this: drivers/thermal/intel_pch_thermal.c:184:14: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types] .get_temp = pch_thermal_get_temp, ^ drivers/thermal/intel_pch_thermal.c:184:14: note: (near initialization for ‘tzd_ops.get_temp’) drivers/thermal/intel_pch_thermal.c:186:19: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types] .get_trip_temp = pch_get_trip_temp, ^ drivers/thermal/intel_pch_thermal.c:186:19: note: (near initialization for ‘tzd_ops.get_trip_temp’) This fixes it. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
Merge fourth patch-bomb from Andrew Morton: - sys_membarier syscall - seq_file interface changes - a few misc fixups * emailed patches from Andrew Morton <akpm@linux-foundation.org>: revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each" mm/early_ioremap: add explicit #include of asm/early_ioremap.h fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void selftests: enhance membarrier syscall test selftests: add membarrier syscall test sys_membarrier(): system-wide memory barrier (generic, x86) MODSIGN: fix a compilation warning in extract-cert
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