- 30 Jul, 2020 1 commit
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Paolo Bonzini authored
Merge tag 'kvmarm-fixes-5.8-4' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master KVM/arm64 fixes for Linux 5.8, take #3 - Fix a corner case of a new mapping inheriting exec permission without and yet bypassing invalidation of the I-cache - Make sure PtrAuth predicates oinly generate inline code for the non-VHE hypervisor code
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- 28 Jul, 2020 2 commits
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Will Deacon authored
If a stage-2 page-table contains an executable, read-only mapping at the pte level (e.g. due to dirty logging being enabled), a subsequent write fault to the same page which tries to install a larger block mapping (e.g. due to dirty logging having been disabled) will erroneously inherit the exec permission and consequently skip I-cache invalidation for the rest of the block. Ensure that exec permission is only inherited by write faults when the new mapping is of the same size as the existing one. A subsequent instruction abort will result in I-cache invalidation for the entire block mapping. Signed-off-by:
Will Deacon <will@kernel.org> Signed-off-by:
Marc Zyngier <maz@kernel.org> Tested-by:
Quentin Perret <qperret@google.com> Reviewed-by:
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Marc Zyngier authored
So far, vcpu_has_ptrauth() is implemented in terms of system_supports_*_auth() calls, which are declared "inline". In some specific conditions (clang and SCS), the "inline" very much turns into an "out of line", which leads to a fireworks when this predicate is evaluated on a non-VHE system (right at the beginning of __hyp_handle_ptrauth). Instead, make sure vcpu_has_ptrauth gets expanded inline by directly using the cpus_have_final_cap() helpers, which are __always_inline, generate much better code, and are the only thing that make sense when running at EL2 on a nVHE system. Fixes: 29eb5a3c ("KVM: arm64: Handle PtrAuth traps early") Reported-by:
Nathan Chancellor <natechancellor@gmail.com> Reported-by:
Nick Desaulniers <ndesaulniers@google.com> Signed-off-by:
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- 27 Jul, 2020 3 commits
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Paolo Bonzini authored
hdr.vmx.flags is meant for future extensions to the ABI, rejecting invalid flags is necessary to avoid broken half-loads of the nVMX state. Signed-off-by:Paolo Bonzini <pbonzini@redhat.com>
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Paolo Bonzini authored
A missing VMCS12 was not causing -EINVAL (it was just read with copy_from_user, so it is not a security issue, but it is still wrong). Test for VMCS12 validity and reject the nested state if a VMCS12 is required but not present. Signed-off-by: -
Paolo Bonzini authored
Setting KVM_STATE_NESTED_GUEST_MODE enables various consistency checks on VMCS12 and therefore causes KVM_SET_NESTED_STATE to fail spuriously with -EINVAL. Do not set the flag so that we're sure to cover the conditions included by the test, and cover the case where VMCS12 is set and KVM_SET_NESTED_STATE is called with invalid VMCS12 contents. Signed-off-by:
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- 10 Jul, 2020 2 commits
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Huacai Chen authored
Commit dc6d95b1 ("KVM: MIPS: Add more MMIO load/store instructions emulation") introduced some 64bit load/store instructions emulation which are unavailable on 32bit platform, and it causes build errors: arch/mips/kvm/emulate.c: In function 'kvm_mips_emulate_store': arch/mips/kvm/emulate.c:1734:6: error: right shift count >= width of type [-Werror] ((vcpu->arch.gprs[rt] >> 56) & 0xff); ^ arch/mips/kvm/emulate.c:1738:6: error: right shift count >= width of type [-Werror] ((vcpu->arch.gprs[rt] >> 48) & 0xffff); ^ arch/mips/kvm/emulate.c:1742:6: error: right shift count >= width of type [-Werror] ((vcpu->arch.gprs[rt] >> 40) & 0xffffff); ^ arch/mips/kvm/emulate.c:1746:6: error: right shift count >= width of type [-Werror] ((vcpu->arch.gprs[rt] >> 32) & 0xffffffff); ^ arch/mips/kvm/emulate.c:1796:6: error: left shift count >= width of type [-Werror] (vcpu->arch.gprs[rt] << 32); ^ arch/mips/kvm/emulate.c:1800:6: error: left shift count >= width of type [-Werror] (vcpu->arch.gprs[rt] << 40); ^ arch/mips/kvm/emulate.c:1804:6: error: left shift count >= width of type [-Werror] (vcpu->arch.gprs[rt] << 48); ^ arch/mips/kvm/emulate.c:1808:6: error: left shift count >= width of type [-Werror] (vcpu->arch.gprs[rt] << 56); ^ cc1: all warnings being treated as errors make[3]: *** [arch/mips/kvm/emulate.o] Error 1 So, use #if defined(CONFIG_64BIT) && defined(CONFIG_KVM_MIPS_VZ) to guard the 64bit load/store instructions emulation. Reported-by:
kernel test robot <lkp@intel.com> Fixes: dc6d95b1 ("KVM: MIPS: Add more MMIO load/store instructions emulation") Signed-off-by:
Huacai Chen <chenhc@lemote.com> Message-Id: <1594365797-536-1-git-send-email-chenhc@lemote.com> Signed-off-by:
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Paolo Bonzini authored
Commit 850448f3 ("KVM: nVMX: Fix VMX preemption timer migration", 2020-06-01) accidentally broke nVMX live migration from older version by changing the userspace ABI. Restore it and, while at it, ensure that vmx->nested.has_preemption_timer_deadline is always initialized according to the KVM_STATE_VMX_PREEMPTION_TIMER_DEADLINE flag. Cc: Makarand Sonare <makarandsonare@google.com> Fixes: 850448f3 ("KVM: nVMX: Fix VMX preemption timer migration") Reviewed-by:
Jim Mattson <jmattson@google.com> Signed-off-by:
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- 06 Jul, 2020 3 commits
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Paolo Bonzini authored
Merge tag 'kvmarm-fixes-5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master KVM/arm fixes for 5.8, take #3 - Disable preemption on context-switching PMU EL0 state happening on system register trap - Don't clobber X0 when tearing down KVM via a soft reset (kexec)
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Andrew Scull authored
HVC_SOFT_RESTART is given values for x0-2 that it should installed before exiting to the new address so should not set x0 to stub HVC success or failure code. Fixes: af42f204 ("arm64: hyp-stub: Zero x0 on successful stub handling") Cc: stable@vger.kernel.org Signed-off-by:
Andrew Scull <ascull@google.com> Signed-off-by:
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Marc Zyngier authored
Commit 07da1ffa ("KVM: arm64: Remove host_cpu_context member from vcpu structure") has, by removing the host CPU context pointer, exposed that kvm_vcpu_pmu_restore_guest is called in preemptible contexts: [ 266.932442] BUG: using smp_processor_id() in preemptible [00000000] code: qemu-system-aar/779 [ 266.939721] caller is debug_smp_processor_id+0x20/0x30 [ 266.944157] CPU: 2 PID: 779 Comm: qemu-system-aar Tainted: G E 5.8.0-rc3-00015-g8d4aa58b2fe3 #1374 [ 266.954268] Hardware name: amlogic w400/w400, BIOS 2020.04 05/22/2020 [ 266.960640] Call trace: [ 266.963064] dump_backtrace+0x0/0x1e0 [ 266.966679] show_stack+0x20/0x30 [ 266.969959] dump_stack+0xe4/0x154 [ 266.973338] check_preemption_disabled+0xf8/0x108 [ 266.977978] debug_smp_processor_id+0x20/0x30 [ 266.982307] kvm_vcpu_pmu_restore_guest+0x2c/0x68 [ 266.986949] access_pmcr+0xf8/0x128 [ 266.990399] perform_access+0x8c/0x250 [ 266.994108] kvm_handle_sys_reg+0x10c/0x2f8 [ 266.998247] handle_exit+0x78/0x200 [ 267.001697] kvm_arch_vcpu_ioctl_run+0x2ac/0xab8 Note that the bug was always there, it is only the switch to using percpu accessors that made it obvious. The fix is to wrap these accesses in a preempt-disabled section, so that we sample a coherent context on trap from the guest. Fixes: 435e53fb ("arm64: KVM: Enable VHE support for :G/:H perf event modifiers") Cc:: Andrew Murray <amurray@thegoodpenguin.co.uk> Signed-off-by:
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- 03 Jul, 2020 3 commits
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Sean Christopherson authored
Use the "common" KVM_POSSIBLE_CR*_GUEST_BITS defines to initialize the CR0/CR4 guest host masks instead of duplicating most of the CR4 mask and open coding the CR0 mask. SVM doesn't utilize the masks, i.e. the masks are effectively VMX specific even if they're not named as such. This avoids duplicate code, better documents the guest owned CR0 bit, and eliminates the need for a build-time assertion to keep VMX and x86 synchronized. Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200703040422.31536-3-sean.j.christopherson@intel.com> Signed-off-by:
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Sean Christopherson authored
Mark CR4.TSD as being possibly owned by the guest as that is indeed the case on VMX. Without TSD being tagged as possibly owned by the guest, a targeted read of CR4 to get TSD could observe a stale value. This bug is benign in the current code base as the sole consumer of TSD is the emulator (for RDTSC) and the emulator always "reads" the entirety of CR4 when grabbing bits. Add a build-time assertion in to ensure VMX doesn't hand over more CR4 bits without also updating x86. Fixes: 52ce3c21 ("x86,kvm,vmx: Don't trap writes to CR4.TSD") Cc: stable@vger.kernel.org Signed-off-by:
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Sean Christopherson authored
Inject a #GP on MOV CR4 if CR4.LA57 is toggled in 64-bit mode, which is illegal per Intel's SDM: CR4.LA57 57-bit linear addresses (bit 12 of CR4) ... blah blah blah ... This bit cannot be modified in IA-32e mode. Note, the pseudocode for MOV CR doesn't call out the fault condition, which is likely why the check was missed during initial development. This is arguably an SDM bug and will hopefully be fixed in future release of the SDM. Fixes: fd8cb433 ("KVM: MMU: Expose the LA57 feature to VM.") Cc: stable@vger.kernel.org Reported-by:Sebastien Boeuf <sebastien.boeuf@intel.com> Signed-off-by:
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- 02 Jul, 2020 1 commit
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Paolo Bonzini authored
Sparse complains on a call to get_compat_sigset, fix it. The "if" right above explains that sigmask_arg->sigset is basically a compat_sigset_t. Signed-off-by:
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- 01 Jul, 2020 1 commit
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Paolo Bonzini authored
Merge tag 'kvmarm-fixes-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master KVM/arm fixes for 5.8, take #2 - Make sure a vcpu becoming non-resident doesn't race against the doorbell delivery - Only advertise pvtime if accounting is enabled - Return the correct error code if reset fails with SVE - Make sure that pseudo-NMI functions are annotated as __always_inline
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- 30 Jun, 2020 1 commit
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Paolo Bonzini authored
Bit 8 would be the "global" bit, which does not quite make sense for non-leaf page table entries. Intel ignores it; AMD ignores it in PDEs and PDPEs, but reserves it in PML4Es. Probably, earlier versions of the AMD manual documented it as reserved in PDPEs as well, and that behavior made it into KVM as well as kvm-unit-tests; fix it. Cc: stable@vger.kernel.org Reported-by:
Nadav Amit <namit@vmware.com> Fixes: a0c0feb5 ("KVM: x86: reserve bit 8 of non-leaf PDPEs and PML4Es in 64-bit mode on AMD", 2014-09-03) Signed-off-by:
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- 29 Jun, 2020 1 commit
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Wanpeng Li authored
Syzbot reported that: CPU: 1 PID: 6780 Comm: syz-executor153 Not tainted 5.7.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__apic_accept_irq+0x46/0xb80 Call Trace: kvm_arch_async_page_present+0x7de/0x9e0 kvm_check_async_pf_completion+0x18d/0x400 kvm_arch_vcpu_ioctl_run+0x18bf/0x69f0 kvm_vcpu_ioctl+0x46a/0xe20 ksys_ioctl+0x11a/0x180 __x64_sys_ioctl+0x6f/0xb0 do_syscall_64+0xf6/0x7d0 entry_SYSCALL_64_after_hwframe+0x49/0xb3 The testcase enables APF mechanism in MSR_KVM_ASYNC_PF_EN with ASYNC_PF_INT enabled w/o setting MSR_KVM_ASYNC_PF_INT before, what's worse, interrupt based APF 'page ready' event delivery depends on in kernel lapic, however, we didn't bail out when lapic is not in kernel during guest setting MSR_KVM_ASYNC_PF_EN which causes the null-ptr-deref in host later. This patch fixes it. Reported-by: syzbot+1bf777dfdde86d64b89b@syzkaller.appspotmail.com Fixes: 2635b5c4 (KVM: x86: interrupt based APF 'page ready' event delivery) Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1593426391-8231-1-git-send-email-wanpengli@tencent.com> Signed-off-by:
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- 24 Jun, 2020 1 commit
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Paolo Bonzini authored
Merge tag 'kvm-s390-master-5.8-3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-master The current number of KVM_IRQCHIP_NUM_PINS results in an order 3 allocation (32kb) for each guest start/restart which can result in OOM killer activity when kernel memory is fragmented enough. This fix reduces the number of iopins as s390 doesn't use them, hence reducing the memory footprint.
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- 23 Jun, 2020 5 commits
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Marc Zyngier authored
When making a vPE non-resident because it has hit a blocking WFI, the doorbell can fire at any time after the write to the RD. Crucially, it can fire right between the write to GICR_VPENDBASER and the write to the pending_last field in the its_vpe structure. This means that we would overwrite pending_last with stale data, and potentially not wakeup until some unrelated event (such as a timer interrupt) puts the vPE back on the CPU. GICv4 isn't affected by this as we actively mask the doorbell on entering the guest, while GICv4.1 automatically manages doorbell delivery without any hypervisor-driven masking. Use the vpe_lock to synchronize such update, which solves the problem altogether. Fixes: ae699ad3 ("irqchip/gic-v4.1: Move doorbell management to the GICv4 abstraction layer") Reported-by:
Zenghui Yu <yuzenghui@huawei.com> Signed-off-by:
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Sean Christopherson authored
Remove vcpu_vmx.host_pkru, which got left behind when PKRU support was moved to common x86 code. No functional change intended. Fixes: 37486135 ("KVM: x86: Fix pkru save/restore when guest CR4.PKE=0, move it to x86.c") Signed-off-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by:
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Marcelo Tosatti authored
The Linux TSC calibration procedure is subject to small variations (its common to see +-1 kHz difference between reboots on a given CPU, for example). So migrating a guest between two hosts with identical processor can fail, in case of a small variation in calibrated TSC between them. Without TSC scaling, the current kernel interface will either return an error (if user_tsc_khz <= tsc_khz) or enable TSC catchup mode. This change enables the following TSC tolerance check to accept KVM_SET_TSC_KHZ within tsc_tolerance_ppm (which is 250ppm by default). /* * Compute the variation in TSC rate which is acceptable * within the range of tolerance and decide if the * rate being applied is within that bounds of the hardware * rate. If so, no scaling or compensation need be done. */ thresh_lo = adjust_tsc_khz(tsc_khz, -tsc_tolerance_ppm); thresh_hi = adjust_tsc_khz(tsc_khz, tsc_tolerance_ppm); if (user_tsc_khz < thresh_lo || user_tsc_khz > thresh_hi) { pr_debug("kvm: requested TSC rate %u falls outside tolerance [%u,%u]\n", user_tsc_khz, thresh_lo, thresh_hi); use_scaling = 1; } NTP daemon in the guest can correct this difference (NTP can correct upto 500ppm). Signed-off-by:Marcelo Tosatti <mtosatti@redhat.com> Message-Id: <20200616114741.GA298183@fuller.cnet> Signed-off-by:
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Xiaoyao Li authored
Only MSR address range 0x800 through 0x8ff is architecturally reserved and dedicated for accessing APIC registers in x2APIC mode. Fixes: 0105d1a5 ("KVM: x2apic interface to lapic") Signed-off-by:
Xiaoyao Li <xiaoyao.li@intel.com> Message-Id: <20200616073307.16440-1-xiaoyao.li@intel.com> Cc: stable@vger.kernel.org Reviewed-by:
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Sean Christopherson authored
Remove support for context switching between the guest's and host's desired UMWAIT_CONTROL. Propagating the guest's value to hardware isn't required for correct functionality, e.g. KVM intercepts reads and writes to the MSR, and the latency effects of the settings controlled by the MSR are not architecturally visible. As a general rule, KVM should not allow the guest to control power management settings unless explicitly enabled by userspace, e.g. see KVM_CAP_X86_DISABLE_EXITS. E.g. Intel's SDM explicitly states that C0.2 can improve the performance of SMT siblings. A devious guest could disable C0.2 so as to improve the performance of their workloads at the detriment to workloads running in the host or on other VMs. Wholesale removal of UMWAIT_CONTROL context switching also fixes a race condition where updates from the host may cause KVM to enter the guest with the incorrect value. Because updates are are propagated to all CPUs via IPI (SMP function callback), the value in hardware may be stale with respect to the cached value and KVM could enter the guest with the wrong value in hardware. As above, the guest can't observe the bad value, but it's a weird and confusing wart in the implementation. Removal also fixes the unnecessary usage of VMX's atomic load/store MSR lists. Using the lists is only necessary for MSRs that are required for correct functionality immediately upon VM-Enter/VM-Exit, e.g. EFER on old hardware, or for MSRs that need to-the-uop precision, e.g. perf related MSRs. For UMWAIT_CONTROL, the effects are only visible in the kernel via TPAUSE/delay(), and KVM doesn't do any form of delay in vcpu_vmx_run(). Using the atomic lists is undesirable as they are more expensive than direct RDMSR/WRMSR. Furthermore, even if giving the guest control of the MSR is legitimate, e.g. in pass-through scenarios, it's not clear that the benefits would outweigh the overhead. E.g. saving and restoring an MSR across a VMX roundtrip costs ~250 cycles, and if the guest diverged from the host that cost would be paid on every run of the guest. In other words, if there is a legitimate use case then it should be enabled by a new per-VM capability. Note, KVM still needs to emulate MSR_IA32_UMWAIT_CONTROL so that it can correctly expose other WAITPKG features to the guest, e.g. TPAUSE, UMWAIT and UMONITOR. Fixes: 6e3ba4ab ("KVM: vmx: Emulate MSR IA32_UMWAIT_CONTROL") Cc: stable@vger.kernel.org Cc: Jingqi Liu <jingqi.liu@intel.com> Cc: Tao Xu <tao3.xu@intel.com> Signed-off-by:
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- 22 Jun, 2020 7 commits
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Sean Christopherson authored
Explicitly pass the L2 GPA to kvm_arch_write_log_dirty(), which for all intents and purposes is vmx_write_pml_buffer(), instead of having the latter pull the GPA from vmcs.GUEST_PHYSICAL_ADDRESS. If the dirty bit update is the result of KVM emulation (rare for L2), then the GPA in the VMCS may be stale and/or hold a completely unrelated GPA. Fixes: c5f983f6 ("nVMX: Implement emulated Page Modification Logging") Cc: stable@vger.kernel.org Signed-off-by:
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Vitaly Kuznetsov authored
translate_gpa() returns a GPA, assigning it to 'real_gfn' seems obviously wrong. There is no real issue because both 'gpa_t' and 'gfn_t' are u64 and we don't use the value in 'real_gfn' as a GFN, we do real_gfn = gpa_to_gfn(real_gfn); instead. 'If you see a "buffalo" sign on an elephant's cage, do not trust your eyes', but let's fix it for good. No functional change intended. Signed-off-by:
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Paolo Bonzini authored
The following race can cause lost map update events: cpu1 cpu2 apic_map_dirty = true ------------------------------------------------------------ kvm_recalculate_apic_map: pass check mutex_lock(&kvm->arch.apic_map_lock); if (!kvm->arch.apic_map_dirty) and in process of updating map ------------------------------------------------------------- other calls to apic_map_dirty = true might be too late for affected cpu ------------------------------------------------------------- apic_map_dirty = false ------------------------------------------------------------- kvm_recalculate_apic_map: bail out on if (!kvm->arch.apic_map_dirty) To fix it, record the beginning of an update of the APIC map in apic_map_dirty. If another APIC map change switches apic_map_dirty back to DIRTY during the update, kvm_recalculate_apic_map should not make it CLEAN, and the other caller will go through the slow path. Reported-by:Igor Mammedov <imammedo@redhat.com> Signed-off-by:
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Igor Mammedov authored
Guest fails to online hotplugged CPU with error smpboot: do_boot_cpu failed(-1) to wakeup CPU#4 It's caused by the fact that kvm_apic_set_state(), which used to call recalculate_apic_map() unconditionally and pulled hotplugged CPU into apic map, is updating map conditionally on state changes. In this case the APIC map is not considered dirty and the is not updated. Fix the issue by forcing unconditional update from kvm_apic_set_state(), like it used to be. Fixes: 4abaffce ("KVM: LAPIC: Recalculate apic map in batch") Cc: stable@vger.kernel.org Signed-off-by:
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Andrew Jones authored
Ensure we're actually accounting run_delay before we claim that we'll expose it to the guest. If we're not, then we just pretend like steal time isn't supported in order to avoid any confusion. Signed-off-by:
Andrew Jones <drjones@redhat.com> Signed-off-by:
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Steven Price authored
If SVE is enabled then 'ret' can be assigned the return value of kvm_vcpu_enable_sve() which may be 0 causing future "goto out" sites to erroneously return 0 on failure rather than -EINVAL as expected. Remove the initialisation of 'ret' and make setting the return value explicit to avoid this situation in the future. Fixes: 9a3cdf26 ("KVM: arm64/sve: Allow userspace to enable SVE for vcpus") Cc: stable@vger.kernel.org Reported-by:
James Morse <james.morse@arm.com> Signed-off-by:
Steven Price <steven.price@arm.com> Signed-off-by:
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Alexandru Elisei authored
The "inline" keyword is a hint for the compiler to inline a function. The functions system_uses_irq_prio_masking() and gic_write_pmr() are used by the code running at EL2 on a non-VHE system, so mark them as __always_inline to make sure they'll always be part of the .hyp.text section. This fixes the following splat when trying to run a VM: [ 47.625273] Kernel panic - not syncing: HYP panic: [ 47.625273] PS:a00003c9 PC:0000ca0b42049fc4 ESR:86000006 [ 47.625273] FAR:0000ca0b42049fc4 HPFAR:0000000010001000 PAR:0000000000000000 [ 47.625273] VCPU:0000000000000000 [ 47.647261] CPU: 1 PID: 217 Comm: kvm-vcpu-0 Not tainted 5.8.0-rc1-ARCH+ #61 [ 47.654508] Hardware name: Globalscale Marvell ESPRESSOBin Board (DT) [ 47.661139] Call trace: [ 47.663659] dump_backtrace+0x0/0x1cc [ 47.667413] show_stack+0x18/0x24 [ 47.670822] dump_stack+0xb8/0x108 [ 47.674312] panic+0x124/0x2f4 [ 47.677446] panic+0x0/0x2f4 [ 47.680407] SMP: stopping secondary CPUs [ 47.684439] Kernel Offset: disabled [ 47.688018] CPU features: 0x240402,20002008 [ 47.692318] Memory Limit: none [ 47.695465] ---[ end Kernel panic - not syncing: HYP panic: [ 47.695465] PS:a00003c9 PC:0000ca0b42049fc4 ESR:86000006 [ 47.695465] FAR:0000ca0b42049fc4 HPFAR:0000000010001000 PAR:0000000000000000 [ 47.695465] VCPU:0000000000000000 ]--- The instruction abort was caused by the code running at EL2 trying to fetch an instruction which wasn't mapped in the EL2 translation tables. Using objdump showed the two functions as separate symbols in the .text section. Fixes: 85738e05 ("arm64: kvm: Unmask PMR before entering guest") Cc: stable@vger.kernel.org Signed-off-by:
Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by:
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- 19 Jun, 2020 1 commit
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Vitaly Kuznetsov authored
Guest crashes are observed on a Cascade Lake system when 'perf top' is launched on the host, e.g. BUG: unable to handle kernel paging request at fffffe0000073038 PGD 7ffa7067 P4D 7ffa7067 PUD 7ffa6067 PMD 7ffa5067 PTE ffffffffff120 Oops: 0000 [#1] SMP PTI CPU: 1 PID: 1 Comm: systemd Not tainted 4.18.0+ #380 ... Call Trace: serial8250_console_write+0xfe/0x1f0 call_console_drivers.constprop.0+0x9d/0x120 console_unlock+0x1ea/0x460 Call traces are different but the crash is imminent. The problem was blindly bisected to the commit 041bc42c ("KVM: VMX: Micro-optimize vmexit time when not exposing PMU"). It was also confirmed that the issue goes away if PMU is exposed to the guest. With some instrumentation of the guest we can see what is being switched (when we do atomic_switch_perf_msrs()): vmx_vcpu_run: switching 2 msrs vmx_vcpu_run: switching MSR38f guest: 70000000d host: 70000000f vmx_vcpu_run: switching MSR3f1 guest: 0 host: 2 The current guess is that PEBS (MSR_IA32_PEBS_ENABLE, 0x3f1) is to blame. Regardless of whether PMU is exposed to the guest or not, PEBS needs to be disabled upon switch. This reverts commit 041bc42c. Reported-by:
Maxime Coquelin <maxime.coquelin@redhat.com> Signed-off-by:
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- 18 Jun, 2020 1 commit
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Christian Borntraeger authored
The current number of KVM_IRQCHIP_NUM_PINS results in an order 3 allocation (32kb) for each guest start/restart. This can result in OOM killer activity even with free swap when the memory is fragmented enough: kernel: qemu-system-s39 invoked oom-killer: gfp_mask=0x440dc0(GFP_KERNEL_ACCOUNT|__GFP_COMP|__GFP_ZERO), order=3, oom_score_adj=0 kernel: CPU: 1 PID: 357274 Comm: qemu-system-s39 Kdump: loaded Not tainted 5.4.0-29-generic #33-Ubuntu kernel: Hardware name: IBM 8562 T02 Z06 (LPAR) kernel: Call Trace: kernel: ([<00000001f848fe2a>] show_stack+0x7a/0xc0) kernel: [<00000001f8d3437a>] dump_stack+0x8a/0xc0 kernel: [<00000001f8687032>] dump_header+0x62/0x258 kernel: [<00000001f8686122>] oom_kill_process+0x172/0x180 kernel: [<00000001f8686abe>] out_of_memory+0xee/0x580 kernel: [<00000001f86e66b8>] __alloc_pages_slowpath+0xd18/0xe90 kernel: [<00000001f86e6ad4>] __alloc_pages_nodemask+0x2a4/0x320 kernel: [<00000001f86b1ab4>] kmalloc_order+0x34/0xb0 kernel: [<00000001f86b1b62>] kmalloc_order_trace+0x32/0xe0 kernel: [<00000001f84bb806>] kvm_set_irq_routing+0xa6/0x2e0 kernel: [<00000001f84c99a4>] kvm_arch_vm_ioctl+0x544/0x9e0 kernel: [<00000001f84b8936>] kvm_vm_ioctl+0x396/0x760 kernel: [<00000001f875df66>] do_vfs_ioctl+0x376/0x690 kernel: [<00000001f875e304>] ksys_ioctl+0x84/0xb0 kernel: [<00000001f875e39a>] __s390x_sys_ioctl+0x2a/0x40 kernel: [<00000001f8d55424>] system_call+0xd8/0x2c8 As far as I can tell s390x does not use the iopins as we bail our for anything other than KVM_IRQ_ROUTING_S390_ADAPTER and the chip/pin is only used for KVM_IRQ_ROUTING_IRQCHIP. So let us use a small number to reduce the memory footprint. Signed-off-by:
Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by:
Cornelia Huck <cohuck@redhat.com> Reviewed-by:
David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20200617083620.5409-1-borntraeger@de.ibm.com
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- 15 Jun, 2020 3 commits
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Sean Christopherson authored
Add is_intr_type() and is_intr_type_n() to consolidate the boilerplate code for querying a specific type of interrupt given an encoded value from VMCS.VM_{ENTER,EXIT}_INTR_INFO, with and without an associated vector respectively. Signed-off-by: -
Qian Cai authored
For some reasons, running a simple qemu-kvm command with KCSAN will reset AMD hosts. It turns out svm_vcpu_run() could not be instrumented. Disable it for now. # /usr/libexec/qemu-kvm -name ubuntu-18.04-server-cloudimg -cpu host -smp 2 -m 2G -hda ubuntu-18.04-server-cloudimg.qcow2 === console output === Kernel 5.6.0-next-20200408+ on an x86_64 hp-dl385g10-05 login: <...host reset...> HPE ProLiant System BIOS A40 v1.20 (03/09/2018) (C) Copyright 1982-2018 Hewlett Packard Enterprise Development LP Early system initialization, please wait... Signed-off-by:
Qian Cai <cai@lca.pw> Message-Id: <20200415153709.1559-1-cai@lca.pw> Signed-off-by:
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Huacai Chen authored
During the KVM merging progress, a CONFIG_CPU_LOONGSON64 guard in commit 7f2a83f1 ("KVM: MIPS: Add CPUCFG emulation for Loongson-3") is missing by accident. So add it to avoid building error. Fixes: 7f2a83f1 ("KVM: MIPS: Add CPUCFG emulation for Loongson-3") Reported-by:
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- 14 Jun, 2020 4 commits
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Linus Torvalds authored
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git://github.com/micah-morton/linuxLinus Torvalds authored
Pull SafeSetID update from Micah Morton: "Add additional LSM hooks for SafeSetID SafeSetID is capable of making allow/deny decisions for set*uid calls on a system, and we want to add similar functionality for set*gid calls. The work to do that is not yet complete, so probably won't make it in for v5.8, but we are looking to get this simple patch in for v5.8 since we have it ready. We are planning on the rest of the work for extending the SafeSetID LSM being merged during the v5.9 merge window" * tag 'LSM-add-setgid-hook-5.8-author-fix' of git://github.com/micah-morton/linux: security: Add LSM hooks to set*gid syscalls
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Thomas Cedeno authored
The SafeSetID LSM uses the security_task_fix_setuid hook to filter set*uid() syscalls according to its configured security policy. In preparation for adding analagous support in the LSM for set*gid() syscalls, we add the requisite hook here. Tested by putting print statements in the security_task_fix_setgid hook and seeing them get hit during kernel boot. Signed-off-by:
Thomas Cedeno <thomascedeno@google.com> Signed-off-by:
Micah Morton <mortonm@chromium.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linuxLinus Torvalds authored
Pull btrfs updates from David Sterba: "This reverts the direct io port to iomap infrastructure of btrfs merged in the first pull request. We found problems in invalidate page that don't seem to be fixable as regressions or without changing iomap code that would not affect other filesystems. There are four reverts in total, but three of them are followup cleanups needed to revert a43a67a2 cleanly. The result is the buffer head based implementation of direct io. Reverts are not great, but under current circumstances I don't see better options" * tag 'for-5.8-part2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: Revert "btrfs: switch to iomap_dio_rw() for dio" Revert "fs: remove dio_end_io()" Revert "btrfs: remove BTRFS_INODE_READDIO_NEED_LOCK" Revert "btrfs: split btrfs_direct_IO to read and write part"
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