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2020-07-31KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabledWanpeng Li
Prevent setting the tscdeadline timer if the lapic is hw disabled. Fixes: bce87cce88 (KVM: x86: consolidate different ways to test for in-kernel LAPIC) Cc: <stable@vger.kernel.org> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1596165141-28874-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-30Merge tag 'kvmarm-fixes-5.8-4' of ↵Paolo Bonzini
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
2020-07-28KVM: arm64: Don't inherit exec permission across page-table levelsWill Deacon
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: Quentin Perret <qperret@google.com> Cc: Marc Zyngier <maz@kernel.org> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20200723101714.15873-1-will@kernel.org
2020-07-28KVM: arm64: Prevent vcpu_has_ptrauth from generating OOL functionsMarc Zyngier
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: 29eb5a3c57f7 ("KVM: arm64: Handle PtrAuth traps early") Reported-by: Nathan Chancellor <natechancellor@gmail.com> Reported-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Tested-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Link: https://lore.kernel.org/r/20200722162231.3689767-1-maz@kernel.org
2020-07-27KVM: nVMX: check for invalid hdr.vmx.flagsPaolo Bonzini
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>
2020-07-27KVM: nVMX: check for required but missing VMCS12 in KVM_SET_NESTED_STATEPaolo Bonzini
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 <pbonzini@redhat.com>
2020-07-10KVM: MIPS: Fix build errors for 32bit kernelHuacai Chen
Commit dc6d95b153e78ed70b1b2c04a ("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: dc6d95b153e78ed70b1b2c04a ("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: Paolo Bonzini <pbonzini@redhat.com>
2020-07-10KVM: nVMX: fixes for preemption timer migrationPaolo Bonzini
Commit 850448f35aaf ("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: 850448f35aaf ("KVM: nVMX: Fix VMX preemption timer migration") Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-06Merge tag 'kvmarm-fixes-5.8-3' of ↵Paolo Bonzini
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)
2020-07-06KVM: arm64: Stop clobbering x0 for HVC_SOFT_RESTARTAndrew Scull
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: af42f20480bf1 ("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: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200706095259.1338221-1-ascull@google.com
2020-07-06KVM: arm64: PMU: Fix per-CPU access in preemptible contextMarc Zyngier
Commit 07da1ffaa137 ("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: 435e53fb5e21 ("arm64: KVM: Enable VHE support for :G/:H perf event modifiers") Cc:: Andrew Murray <amurray@thegoodpenguin.co.uk> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-07-03KVM: VMX: Use KVM_POSSIBLE_CR*_GUEST_BITS to initialize guest/host masksSean Christopherson
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: Paolo Bonzini <pbonzini@redhat.com>
2020-07-03KVM: x86: Mark CR4.TSD as being possibly owned by the guestSean Christopherson
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: 52ce3c21aec3 ("x86,kvm,vmx: Don't trap writes to CR4.TSD") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200703040422.31536-2-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-03KVM: x86: Inject #GP if guest attempts to toggle CR4.LA57 in 64-bit modeSean Christopherson
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: fd8cb433734ee ("KVM: MMU: Expose the LA57 feature to VM.") Cc: stable@vger.kernel.org Reported-by: Sebastien Boeuf <sebastien.boeuf@intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200703021714.5549-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-07-01Merge tag 'kvmarm-fixes-5.8-2' of ↵Paolo Bonzini
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
2020-06-30KVM: x86: bit 8 of non-leaf PDPEs is not reservedPaolo Bonzini
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: a0c0feb57992 ("KVM: x86: reserve bit 8 of non-leaf PDPEs and PML4Es in 64-bit mode on AMD", 2014-09-03) Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-29KVM: X86: Fix async pf caused null-ptr-derefWanpeng Li
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: 2635b5c4a0 (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: Paolo Bonzini <pbonzini@redhat.com>
2020-06-24Merge tag 'kvm-s390-master-5.8-3' of ↵Paolo Bonzini
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.
2020-06-23KVM: arm64: vgic-v4: Plug race between non-residency and v4.1 doorbellMarc Zyngier
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: ae699ad348cdc ("irqchip/gic-v4.1: Move doorbell management to the GICv4 abstraction layer") Reported-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-06-23KVM: VMX: Remove vcpu_vmx's defunct copy of host_pkruSean Christopherson
Remove vcpu_vmx.host_pkru, which got left behind when PKRU support was moved to common x86 code. No functional change intended. Fixes: 37486135d3a7b ("KVM: x86: Fix pkru save/restore when guest CR4.PKE=0, move it to x86.c") Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200617034123.25647-1-sean.j.christopherson@intel.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-23KVM: x86: allow TSC to differ by NTP correction bounds without TSC scalingMarcelo Tosatti
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: Paolo Bonzini <pbonzini@redhat.com>
2020-06-23KVM: X86: Fix MSR range of APIC registers in X2APIC modeXiaoyao Li
Only MSR address range 0x800 through 0x8ff is architecturally reserved and dedicated for accessing APIC registers in x2APIC mode. Fixes: 0105d1a52640 ("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: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-22KVM: VMX: Stop context switching MSR_IA32_UMWAIT_CONTROLSean Christopherson
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: 6e3ba4abcea56 ("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: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200623005135.10414-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-22KVM: nVMX: Plumb L2 GPA through to PML emulationSean Christopherson
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: c5f983f6e8455 ("nVMX: Implement emulated Page Modification Logging") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200622215832.22090-2-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-22KVM: x86/mmu: Avoid mixing gpa_t with gfn_t in walk_addr_generic()Vitaly Kuznetsov
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: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20200622151435.752560-1-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-22KVM: LAPIC: ensure APIC map is up to date on concurrent update requestsPaolo Bonzini
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: Paolo Bonzini <pbonzini@redhat.com>
2020-06-22kvm: lapic: fix broken vcpu hotplugIgor Mammedov
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: 4abaffce4d25a ("KVM: LAPIC: Recalculate apic map in batch") Cc: stable@vger.kernel.org Signed-off-by: Igor Mammedov <imammedo@redhat.com> Message-Id: <20200622160830.426022-1-imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-22KVM: arm64: pvtime: Ensure task delay accounting is enabledAndrew Jones
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: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200622142710.18677-1-drjones@redhat.com
2020-06-22KVM: arm64: Fix kvm_reset_vcpu() return code being incorrect with SVESteven Price
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: 9a3cdf26e336 ("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: Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20200617105456.28245-1-steven.price@arm.com
2020-06-22KVM: arm64: Annotate hyp NMI-related functions as __always_inlineAlexandru Elisei
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: 85738e05dc38 ("arm64: kvm: Unmask PMR before entering guest") Cc: stable@vger.kernel.org Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com> Signed-off-by: Marc Zyngier <maz@kernel.org> Acked-by: James Morse <james.morse@arm.com> Link: https://lore.kernel.org/r/20200618171254.1596055-1-alexandru.elisei@arm.com
2020-06-19Revert "KVM: VMX: Micro-optimize vmexit time when not exposing PMU"Vitaly Kuznetsov
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 041bc42ce2d0 ("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 041bc42ce2d0efac3b85bbb81dea8c74b81f4ef9. Reported-by: Maxime Coquelin <maxime.coquelin@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20200619094046.654019-1-vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-18KVM: s390: reduce number of IO pins to 1Christian Borntraeger
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
2020-06-15KVM: VMX: Add helpers to identify interrupt type from intr_infoSean Christopherson
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: Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200609014518.26756-1-sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-15kvm/svm: disable KCSAN for svm_vcpu_run()Qian Cai
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: Paolo Bonzini <pbonzini@redhat.com>
2020-06-15KVM: MIPS: Fix a build error for !CPU_LOONGSON64Huacai Chen
During the KVM merging progress, a CONFIG_CPU_LOONGSON64 guard in commit 7f2a83f1c2a941ebfee53 ("KVM: MIPS: Add CPUCFG emulation for Loongson-3") is missing by accident. So add it to avoid building error. Fixes: 7f2a83f1c2a941ebfee53 ("KVM: MIPS: Add CPUCFG emulation for Loongson-3") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Huacai Chen <chenhc@lemote.com> Message-Id: <1592204215-28704-1-git-send-email-chenhc@lemote.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2020-06-13Merge tag 'kbuild-v5.8-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild Pull more Kbuild updates from Masahiro Yamada: - fix build rules in binderfs sample - fix build errors when Kbuild recurses to the top Makefile - covert '---help---' in Kconfig to 'help' * tag 'kbuild-v5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: treewide: replace '---help---' in Kconfig files with 'help' kbuild: fix broken builds because of GZIP,BZIP2,LZOP variables samples: binderfs: really compile this sample and fix build issues
2020-06-13Merge tag 'powerpc-5.8-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fix from Michael Ellerman: "One fix for a recent change which broke nested KVM guests on Power9. Thanks to Alexey Kardashevskiy" * tag 'powerpc-5.8-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: KVM: PPC: Fix nested guest RC bits update
2020-06-13Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-armLinus Torvalds
Pull ARM fixes from Russell King: - fix for "hex" Kconfig default to use 0x0 rather than 0 to allow these to be removed from defconfigs - fix from Ard Biesheuvel for EFI HYP mode booting * tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: ARM: 8985/1: efi/decompressor: deal with HYP mode boot gracefully ARM: 8984/1: Kconfig: set default ZBOOT_ROM_TEXT/BSS value to 0x0
2020-06-13Merge tag 'for-linus' of git://github.com/openrisc/linuxLinus Torvalds
Pull OpenRISC update from Stafford Horne: "One patch found wile I was getting the glibc port ready: fix issue with clone TLS arg getting overwritten" * tag 'for-linus' of git://github.com/openrisc/linux: openrisc: Fix issue with argument clobbering for clone/fork
2020-06-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha Pull alpha updates from Matt Turner: "A few changes for alpha. They're mostly small janitorial fixes but there's also a build fix and most notably a patch from Mikulas that fixes a hang on boot on the Avanti platform, which required quite a bit of work and review" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mattst88/alpha: alpha: Fix build around srm_sysrq_reboot_op alpha: c_next should increase position index alpha: Replace sg++ with sg = sg_next(sg) alpha: fix memory barriers so that they conform to the specification alpha: remove unneeded semicolon in sys_eiger.c alpha: remove unneeded semicolon in osf_sys.c alpha: Replace strncmp with str_has_prefix alpha: fix rtc port ranges alpha: Kconfig: pedantic formatting
2020-06-13Merge tag 'ras-core-2020-06-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 RAS updates from Thomas Gleixner: "RAS updates from Borislav Petkov: - Unmap a whole guest page if an MCE is encountered in it to avoid follow-on MCEs leading to the guest crashing, by Tony Luck. This change collided with the entry changes and the merge resolution would have been rather unpleasant. To avoid that the entry branch was merged in before applying this. The resulting code did not change over the rebase. - AMD MCE error thresholding machinery cleanup and hotplug sanitization, by Thomas Gleixner. - Change the MCE notifiers to denote whether they have handled the error and not break the chain early by returning NOTIFY_STOP, thus giving the opportunity for the later handlers in the chain to see it. By Tony Luck. - Add AMD family 0x17, models 0x60-6f support, by Alexander Monakov. - Last but not least, the usual round of fixes and improvements" * tag 'ras-core-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits) x86/mce/dev-mcelog: Fix -Wstringop-truncation warning about strncpy() x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned EDAC/amd64: Add AMD family 17h model 60h PCI IDs hwmon: (k10temp) Add AMD family 17h model 60h PCI match x86/amd_nb: Add AMD family 17h model 60h PCI IDs x86/mcelog: Add compat_ioctl for 32-bit mcelog support x86/mce: Drop bogus comment about mce.kflags x86/mce: Fixup exception only for the correct MCEs EDAC: Drop the EDAC report status checks x86/mce: Add mce=print_all option x86/mce: Change default MCE logger to check mce->kflags x86/mce: Fix all mce notifiers to update the mce->kflags bitmask x86/mce: Add a struct mce.kflags field x86/mce: Convert the CEC to use the MCE notifier x86/mce: Rename "first" function as "early" x86/mce/amd, edac: Remove report_gart_errors x86/mce/amd: Make threshold bank setting hotplug robust x86/mce/amd: Cleanup threshold device remove path x86/mce/amd: Straighten CPU hotplug path x86/mce/amd: Sanitize thresholding device creation hotplug path ...
2020-06-13Merge tag 'x86-entry-2020-06-12' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 entry updates from Thomas Gleixner: "The x86 entry, exception and interrupt code rework This all started about 6 month ago with the attempt to move the Posix CPU timer heavy lifting out of the timer interrupt code and just have lockless quick checks in that code path. Trivial 5 patches. This unearthed an inconsistency in the KVM handling of task work and the review requested to move all of this into generic code so other architectures can share. Valid request and solved with another 25 patches but those unearthed inconsistencies vs. RCU and instrumentation. Digging into this made it obvious that there are quite some inconsistencies vs. instrumentation in general. The int3 text poke handling in particular was completely unprotected and with the batched update of trace events even more likely to expose to endless int3 recursion. In parallel the RCU implications of instrumenting fragile entry code came up in several discussions. The conclusion of the x86 maintainer team was to go all the way and make the protection against any form of instrumentation of fragile and dangerous code pathes enforcable and verifiable by tooling. A first batch of preparatory work hit mainline with commit d5f744f9a2ac ("Pull x86 entry code updates from Thomas Gleixner") That (almost) full solution introduced a new code section '.noinstr.text' into which all code which needs to be protected from instrumentation of all sorts goes into. Any call into instrumentable code out of this section has to be annotated. objtool has support to validate this. Kprobes now excludes this section fully which also prevents BPF from fiddling with it and all 'noinstr' annotated functions also keep ftrace off. The section, kprobes and objtool changes are already merged. The major changes coming with this are: - Preparatory cleanups - Annotating of relevant functions to move them into the noinstr.text section or enforcing inlining by marking them __always_inline so the compiler cannot misplace or instrument them. - Splitting and simplifying the idtentry macro maze so that it is now clearly separated into simple exception entries and the more interesting ones which use interrupt stacks and have the paranoid handling vs. CR3 and GS. - Move quite some of the low level ASM functionality into C code: - enter_from and exit to user space handling. The ASM code now calls into C after doing the really necessary ASM handling and the return path goes back out without bells and whistels in ASM. - exception entry/exit got the equivivalent treatment - move all IRQ tracepoints from ASM to C so they can be placed as appropriate which is especially important for the int3 recursion issue. - Consolidate the declaration and definition of entry points between 32 and 64 bit. They share a common header and macros now. - Remove the extra device interrupt entry maze and just use the regular exception entry code. - All ASM entry points except NMI are now generated from the shared header file and the corresponding macros in the 32 and 64 bit entry ASM. - The C code entry points are consolidated as well with the help of DEFINE_IDTENTRY*() macros. This allows to ensure at one central point that all corresponding entry points share the same semantics. The actual function body for most entry points is in an instrumentable and sane state. There are special macros for the more sensitive entry points, e.g. INT3 and of course the nasty paranoid #NMI, #MCE, #DB and #DF. They allow to put the whole entry instrumentation and RCU handling into safe places instead of the previous pray that it is correct approach. - The INT3 text poke handling is now completely isolated and the recursion issue banned. Aside of the entry rework this required other isolation work, e.g. the ability to force inline bsearch. - Prevent #DB on fragile entry code, entry relevant memory and disable it on NMI, #MC entry, which allowed to get rid of the nested #DB IST stack shifting hackery. - A few other cleanups and enhancements which have been made possible through this and already merged changes, e.g. consolidating and further restricting the IDT code so the IDT table becomes RO after init which removes yet another popular attack vector - About 680 lines of ASM maze are gone. There are a few open issues: - An escape out of the noinstr section in the MCE handler which needs some more thought but under the aspect that MCE is a complete trainwreck by design and the propability to survive it is low, this was not high on the priority list. - Paravirtualization When PV is enabled then objtool complains about a bunch of indirect calls out of the noinstr section. There are a few straight forward ways to fix this, but the other issues vs. general correctness were more pressing than parawitz. - KVM KVM is inconsistent as well. Patches have been posted, but they have not yet been commented on or picked up by the KVM folks. - IDLE Pretty much the same problems can be found in the low level idle code especially the parts where RCU stopped watching. This was beyond the scope of the more obvious and exposable problems and is on the todo list. The lesson learned from this brain melting exercise to morph the evolved code base into something which can be validated and understood is that once again the violation of the most important engineering principle "correctness first" has caused quite a few people to spend valuable time on problems which could have been avoided in the first place. The "features first" tinkering mindset really has to stop. With that I want to say thanks to everyone involved in contributing to this effort. Special thanks go to the following people (alphabetical order): Alexandre Chartre, Andy Lutomirski, Borislav Petkov, Brian Gerst, Frederic Weisbecker, Josh Poimboeuf, Juergen Gross, Lai Jiangshan, Macro Elver, Paolo Bonzin,i Paul McKenney, Peter Zijlstra, Vitaly Kuznetsov, and Will Deacon" * tag 'x86-entry-2020-06-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (142 commits) x86/entry: Force rcu_irq_enter() when in idle task x86/entry: Make NMI use IDTENTRY_RAW x86/entry: Treat BUG/WARN as NMI-like entries x86/entry: Unbreak __irqentry_text_start/end magic x86/entry: __always_inline CR2 for noinstr lockdep: __always_inline more for noinstr x86/entry: Re-order #DB handler to avoid *SAN instrumentation x86/entry: __always_inline arch_atomic_* for noinstr x86/entry: __always_inline irqflags for noinstr x86/entry: __always_inline debugreg for noinstr x86/idt: Consolidate idt functionality x86/idt: Cleanup trap_init() x86/idt: Use proper constants for table size x86/idt: Add comments about early #PF handling x86/idt: Mark init only functions __init x86/entry: Rename trace_hardirqs_off_prepare() x86/entry: Clarify irq_{enter,exit}_rcu() x86/entry: Remove DBn stacks x86/entry: Remove debug IDT frobbing x86/entry: Optimize local_db_save() for virt ...
2020-06-14treewide: replace '---help---' in Kconfig files with 'help'Masahiro Yamada
Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-13ARM: 8985/1: efi/decompressor: deal with HYP mode boot gracefullyArd Biesheuvel
EFI on ARM only supports short descriptors, and given that it mandates that the MMU and caches are on, it is implied that booting in HYP mode is not supported. However, implementations of EFI exist (i.e., U-Boot) that ignore this requirement, which is not entirely unreasonable, given that it makes HYP mode inaccessible to the operating system. So let's make sure that we can deal with this condition gracefully. We already tolerate booting the EFI stub with the caches off (even though this violates the EFI spec as well), and so we should deal with HYP mode boot with MMU and caches either on or off. - When the MMU and caches are on, we can ignore the HYP stub altogether, since we can carry on executing at HYP. We do need to ensure that we disable the MMU at HYP before entering the kernel proper. - When the MMU and caches are off, we have to drop to SVC mode so that we can set up the page tables using short descriptors. In this case, we need to install the HYP stub as usual, so that we can return to HYP mode before handing over to the kernel proper. Tested-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-06-13ARM: 8984/1: Kconfig: set default ZBOOT_ROM_TEXT/BSS value to 0x0Chris Packham
ZBOOT_ROM_TEXT and ZBOOT_ROM_BSS are defined as 'hex' but had a default of "0". Kconfig will helpfully expand a text entry of 0 to 0x0 but because this is not the same as the default value it was treated as being explicitly set when running 'make savedefconfig' so most arm defconfigs have CONFIG_ZBOOT_ROM_TEXT=0x0 and CONFIG_ZBOOT_ROM_BSS=0x0. Change the default to 0x0 which will mean next time the defconfigs are re-generated the spurious config entries will be removed. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-06-12alpha: Fix build around srm_sysrq_reboot_opJoerg Roedel
The patch introducing the struct was probably never compile tested, because it sets a handler with a wrong function signature. Wrap the handler into a functions with the correct signature to fix the build. Fixes: 0f1c9688a194 ("tty/sysrq: alpha: export and use __sysrq_get_key_op()") Cc: Emil Velikov <emil.l.velikov@gmail.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Matt Turner <mattst88@gmail.com>
2020-06-12alpha: c_next should increase position indexMatt Turner
Signed-off-by: Matt Turner <mattst88@gmail.com>
2020-06-12alpha: Replace sg++ with sg = sg_next(sg)Xu Wang
Replace sg++ with sg = sg_next(sg). Signed-off-by: Xu Wang <vulab@iscas.ac.cn> Signed-off-by: Matt Turner <mattst88@gmail.com>
2020-06-12alpha: fix memory barriers so that they conform to the specificationMikulas Patocka
The commits cd0e00c10672 and 92d7223a7423 broke boot on the Alpha Avanti platform. The patches move memory barriers after a write before the write. The result is that if there's iowrite followed by ioread, there is no barrier between them. The Alpha architecture allows reordering of the accesses to the I/O space, and the missing barrier between write and read causes hang with serial port and real time clock. This patch makes barriers confiorm to the specification. 1. We add mb() before readX_relaxed and writeX_relaxed - memory-barriers.txt claims that these functions must be ordered w.r.t. each other. Alpha doesn't order them, so we need an explicit barrier. 2. We add mb() before reads from the I/O space - so that if there's a write followed by a read, there should be a barrier between them. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Fixes: cd0e00c10672 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering") Fixes: 92d7223a7423 ("alpha: io: reorder barriers to guarantee writeX() and iowriteX() ordering #2") Cc: stable@vger.kernel.org # v4.17+ Acked-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Reviewed-by: Maciej W. Rozycki <macro@linux-mips.org> Signed-off-by: Matt Turner <mattst88@gmail.com>
2020-06-12alpha: remove unneeded semicolon in sys_eiger.cJason Yan
Fix the following coccicheck warning: arch/alpha/kernel/sys_eiger.c:179:2-3: Unneeded semicolon Signed-off-by: Jason Yan <yanaijie@huawei.com> Signed-off-by: Matt Turner <mattst88@gmail.com>