linux_dsm_epyc7002/arch/arm64/include/asm/kvm_host.h

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/*
* Copyright (C) 2012,2013 - ARM Ltd
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* Derived from arch/arm/include/asm/kvm_host.h:
* Copyright (C) 2012 - Virtual Open Systems and Columbia University
* Author: Christoffer Dall <c.dall@virtualopensystems.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ARM64_KVM_HOST_H__
#define __ARM64_KVM_HOST_H__
#include <linux/types.h>
#include <linux/kvm_types.h>
arm64/cpufeature: don't use mutex in bringup path Currently, cpus_set_cap() calls static_branch_enable_cpuslocked(), which must take the jump_label mutex. We call cpus_set_cap() in the secondary bringup path, from the idle thread where interrupts are disabled. Taking a mutex in this path "is a NONO" regardless of whether it's contended, and something we must avoid. We didn't spot this until recently, as ___might_sleep() won't warn for this case until all CPUs have been brought up. This patch avoids taking the mutex in the secondary bringup path. The poking of static keys is deferred until enable_cpu_capabilities(), which runs in a suitable context on the boot CPU. To account for the static keys being set later, cpus_have_const_cap() is updated to use another static key to check whether the const cap keys have been initialised, falling back to the caps bitmap until this is the case. This means that users of cpus_have_const_cap() gain should only gain a single additional NOP in the fast path once the const caps are initialised, but should always see the current cap value. The hyp code should never dereference the caps array, since the caps are initialized before we run the module initcall to initialise hyp. A check is added to the hyp init code to document this requirement. This change will sidestep a number of issues when the upcoming hotplug locking rework is merged. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyniger <marc.zyngier@arm.com> Reviewed-by: Suzuki Poulose <suzuki.poulose@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Sewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-16 21:18:05 +07:00
#include <asm/cpufeature.h>
#include <asm/daifflags.h>
arm64/sve: KVM: Prevent guests from using SVE Until KVM has full SVE support, guests must not be allowed to execute SVE instructions. This patch enables the necessary traps, and also ensures that the traps are disabled again on exit from the guest so that the host can still use SVE if it wants to. On guest exit, high bits of the SVE Zn registers may have been clobbered as a side-effect the execution of FPSIMD instructions in the guest. The existing KVM host FPSIMD restore code is not sufficient to restore these bits, so this patch explicitly marks the CPU as not containing cached vector state for any task, thus forcing a reload on the next return to userspace. This is an interim measure, in advance of adding full SVE awareness to KVM. This marking of cached vector state in the CPU as invalid is done using __this_cpu_write(fpsimd_last_state, NULL) in fpsimd.c. Due to the repeated use of this rather obscure operation, it makes sense to factor it out as a separate helper with a clearer name. This patch factors it out as fpsimd_flush_cpu_state(), and ports all callers to use it. As a side effect of this refactoring, a this_cpu_write() in fpsimd_cpu_pm_notifier() is changed to __this_cpu_write(). This should be fine, since cpu_pm_enter() is supposed to be called only with interrupts disabled. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-31 22:51:16 +07:00
#include <asm/fpsimd.h>
#include <asm/kvm.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_mmio.h>
#define __KVM_HAVE_ARCH_INTC_INITIALIZED
#define KVM_USER_MEM_SLOTS 512
#define KVM_HALT_POLL_NS_DEFAULT 500000
#include <kvm/arm_vgic.h>
#include <kvm/arm_arch_timer.h>
#include <kvm/arm_pmu.h>
#define KVM_MAX_VCPUS VGIC_V3_MAX_CPUS
#define KVM_VCPU_MAX_FEATURES 4
#define KVM_REQ_SLEEP \
KVM_ARCH_REQ_FLAGS(0, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
#define KVM_REQ_IRQ_PENDING KVM_ARCH_REQ(1)
int __attribute_const__ kvm_target_cpu(void);
int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
int kvm_arch_dev_ioctl_check_extension(struct kvm *kvm, long ext);
arm64: kvm: Fix kvm teardown for systems using the extended idmap If memory is located above 1<<VA_BITS, kvm adds an extra level to its page tables, merging the runtime tables and boot tables that contain the idmap. This lets us avoid the trampoline dance during initialisation. This also means there is no trampoline page mapped, so __cpu_reset_hyp_mode() can't call __kvm_hyp_reset() in this page. The good news is the idmap is still mapped, so we don't need the trampoline page. The bad news is we can't call it directly as the idmap is above HYP_PAGE_OFFSET, so its address is masked by kvm_call_hyp. Add a function __extended_idmap_trampoline which will branch into __kvm_hyp_reset in the idmap, change kvm_hyp_reset_entry() to return this address if __kvm_cpu_uses_extended_idmap(). In this case __kvm_hyp_reset() will still switch to the boot tables (which are the merged tables that were already in use), and branch into the idmap (where it already was). This fixes boot failures on these systems, where we fail to execute the missing trampoline page when tearing down kvm in init_subsystems(): [ 2.508922] kvm [1]: 8-bit VMID [ 2.512057] kvm [1]: Hyp mode initialized successfully [ 2.517242] kvm [1]: interrupt-controller@e1140000 IRQ13 [ 2.522622] kvm [1]: timer IRQ3 [ 2.525783] Kernel panic - not syncing: HYP panic: [ 2.525783] PS:200003c9 PC:0000007ffffff820 ESR:86000005 [ 2.525783] FAR:0000007ffffff820 HPFAR:00000000003ffff0 PAR:0000000000000000 [ 2.525783] VCPU: (null) [ 2.525783] [ 2.547667] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G W 4.6.0-rc5+ #1 [ 2.555137] Hardware name: Default string Default string/Default string, BIOS ROD0084E 09/03/2015 [ 2.563994] Call trace: [ 2.566432] [<ffffff80080888d0>] dump_backtrace+0x0/0x240 [ 2.571818] [<ffffff8008088b24>] show_stack+0x14/0x20 [ 2.576858] [<ffffff80083423ac>] dump_stack+0x94/0xb8 [ 2.581899] [<ffffff8008152130>] panic+0x10c/0x250 [ 2.586677] [<ffffff8008152024>] panic+0x0/0x250 [ 2.591281] SMP: stopping secondary CPUs [ 3.649692] SMP: failed to stop secondary CPUs 0-2,4-7 [ 3.654818] Kernel Offset: disabled [ 3.658293] Memory Limit: none [ 3.661337] ---[ end Kernel panic - not syncing: HYP panic: [ 3.661337] PS:200003c9 PC:0000007ffffff820 ESR:86000005 [ 3.661337] FAR:0000007ffffff820 HPFAR:00000000003ffff0 PAR:0000000000000000 [ 3.661337] VCPU: (null) [ 3.661337] Reported-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-30 00:27:03 +07:00
void __extended_idmap_trampoline(phys_addr_t boot_pgd, phys_addr_t idmap_start);
struct kvm_arch {
/* The VMID generation used for the virt. memory system */
u64 vmid_gen;
u32 vmid;
/* 1-level 2nd stage table and lock */
spinlock_t pgd_lock;
pgd_t *pgd;
/* VTTBR value associated with above pgd and vmid */
u64 vttbr;
/* The last vcpu id that ran on each physical CPU */
int __percpu *last_vcpu_ran;
/* The maximum number of vCPUs depends on the used GIC model */
int max_vcpus;
/* Interrupt controller */
struct vgic_dist vgic;
};
#define KVM_NR_MEM_OBJS 40
/*
* We don't want allocation failures within the mmu code, so we preallocate
* enough memory for a single page fault in a cache.
*/
struct kvm_mmu_memory_cache {
int nobjs;
void *objects[KVM_NR_MEM_OBJS];
};
struct kvm_vcpu_fault_info {
u32 esr_el2; /* Hyp Syndrom Register */
u64 far_el2; /* Hyp Fault Address Register */
u64 hpfar_el2; /* Hyp IPA Fault Address Register */
KVM: arm64: Handle RAS SErrors from EL2 on guest exit We expect to have firmware-first handling of RAS SErrors, with errors notified via an APEI method. For systems without firmware-first, add some minimal handling to KVM. There are two ways KVM can take an SError due to a guest, either may be a RAS error: we exit the guest due to an SError routed to EL2 by HCR_EL2.AMO, or we take an SError from EL2 when we unmask PSTATE.A from __guest_exit. The current SError from EL2 code unmasks SError and tries to fence any pending SError into a single instruction window. It then leaves SError unmasked. With the v8.2 RAS Extensions we may take an SError for a 'corrected' error, but KVM is only able to handle SError from EL2 if they occur during this single instruction window... The RAS Extensions give us a new instruction to synchronise and consume SErrors. The RAS Extensions document (ARM DDI0587), '2.4.1 ESB and Unrecoverable errors' describes ESB as synchronising SError interrupts generated by 'instructions, translation table walks, hardware updates to the translation tables, and instruction fetches on the same PE'. This makes ESB equivalent to KVMs existing 'dsb, mrs-daifclr, isb' sequence. Use the alternatives to synchronise and consume any SError using ESB instead of unmasking and taking the SError. Set ARM_EXIT_WITH_SERROR_BIT in the exit_code so that we can restart the vcpu if it turns out this SError has no impact on the vcpu. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16 02:39:05 +07:00
u64 disr_el1; /* Deferred [SError] Status Register */
};
/*
* 0 is reserved as an invalid value.
* Order should be kept in sync with the save/restore code.
*/
enum vcpu_sysreg {
__INVALID_SYSREG__,
MPIDR_EL1, /* MultiProcessor Affinity Register */
CSSELR_EL1, /* Cache Size Selection Register */
SCTLR_EL1, /* System Control Register */
ACTLR_EL1, /* Auxiliary Control Register */
CPACR_EL1, /* Coprocessor Access Control */
TTBR0_EL1, /* Translation Table Base Register 0 */
TTBR1_EL1, /* Translation Table Base Register 1 */
TCR_EL1, /* Translation Control Register */
ESR_EL1, /* Exception Syndrome Register */
AFSR0_EL1, /* Auxiliary Fault Status Register 0 */
AFSR1_EL1, /* Auxiliary Fault Status Register 1 */
FAR_EL1, /* Fault Address Register */
MAIR_EL1, /* Memory Attribute Indirection Register */
VBAR_EL1, /* Vector Base Address Register */
CONTEXTIDR_EL1, /* Context ID Register */
TPIDR_EL0, /* Thread ID, User R/W */
TPIDRRO_EL0, /* Thread ID, User R/O */
TPIDR_EL1, /* Thread ID, Privileged */
AMAIR_EL1, /* Aux Memory Attribute Indirection Register */
CNTKCTL_EL1, /* Timer Control Register (EL1) */
PAR_EL1, /* Physical Address Register */
MDSCR_EL1, /* Monitor Debug System Control Register */
MDCCINT_EL1, /* Monitor Debug Comms Channel Interrupt Enable Reg */
DISR_EL1, /* Deferred Interrupt Status Register */
/* Performance Monitors Registers */
PMCR_EL0, /* Control Register */
PMSELR_EL0, /* Event Counter Selection Register */
PMEVCNTR0_EL0, /* Event Counter Register (0-30) */
PMEVCNTR30_EL0 = PMEVCNTR0_EL0 + 30,
PMCCNTR_EL0, /* Cycle Counter Register */
PMEVTYPER0_EL0, /* Event Type Register (0-30) */
PMEVTYPER30_EL0 = PMEVTYPER0_EL0 + 30,
PMCCFILTR_EL0, /* Cycle Count Filter Register */
PMCNTENSET_EL0, /* Count Enable Set Register */
PMINTENSET_EL1, /* Interrupt Enable Set Register */
PMOVSSET_EL0, /* Overflow Flag Status Set Register */
PMSWINC_EL0, /* Software Increment Register */
PMUSERENR_EL0, /* User Enable Register */
/* 32bit specific registers. Keep them at the end of the range */
DACR32_EL2, /* Domain Access Control Register */
IFSR32_EL2, /* Instruction Fault Status Register */
FPEXC32_EL2, /* Floating-Point Exception Control Register */
DBGVCR32_EL2, /* Debug Vector Catch Register */
NR_SYS_REGS /* Nothing after this line! */
};
/* 32bit mapping */
#define c0_MPIDR (MPIDR_EL1 * 2) /* MultiProcessor ID Register */
#define c0_CSSELR (CSSELR_EL1 * 2)/* Cache Size Selection Register */
#define c1_SCTLR (SCTLR_EL1 * 2) /* System Control Register */
#define c1_ACTLR (ACTLR_EL1 * 2) /* Auxiliary Control Register */
#define c1_CPACR (CPACR_EL1 * 2) /* Coprocessor Access Control */
#define c2_TTBR0 (TTBR0_EL1 * 2) /* Translation Table Base Register 0 */
#define c2_TTBR0_high (c2_TTBR0 + 1) /* TTBR0 top 32 bits */
#define c2_TTBR1 (TTBR1_EL1 * 2) /* Translation Table Base Register 1 */
#define c2_TTBR1_high (c2_TTBR1 + 1) /* TTBR1 top 32 bits */
#define c2_TTBCR (TCR_EL1 * 2) /* Translation Table Base Control R. */
#define c3_DACR (DACR32_EL2 * 2)/* Domain Access Control Register */
#define c5_DFSR (ESR_EL1 * 2) /* Data Fault Status Register */
#define c5_IFSR (IFSR32_EL2 * 2)/* Instruction Fault Status Register */
#define c5_ADFSR (AFSR0_EL1 * 2) /* Auxiliary Data Fault Status R */
#define c5_AIFSR (AFSR1_EL1 * 2) /* Auxiliary Instr Fault Status R */
#define c6_DFAR (FAR_EL1 * 2) /* Data Fault Address Register */
#define c6_IFAR (c6_DFAR + 1) /* Instruction Fault Address Register */
#define c7_PAR (PAR_EL1 * 2) /* Physical Address Register */
#define c7_PAR_high (c7_PAR + 1) /* PAR top 32 bits */
#define c10_PRRR (MAIR_EL1 * 2) /* Primary Region Remap Register */
#define c10_NMRR (c10_PRRR + 1) /* Normal Memory Remap Register */
#define c12_VBAR (VBAR_EL1 * 2) /* Vector Base Address Register */
#define c13_CID (CONTEXTIDR_EL1 * 2) /* Context ID Register */
#define c13_TID_URW (TPIDR_EL0 * 2) /* Thread ID, User R/W */
#define c13_TID_URO (TPIDRRO_EL0 * 2)/* Thread ID, User R/O */
#define c13_TID_PRIV (TPIDR_EL1 * 2) /* Thread ID, Privileged */
#define c10_AMAIR0 (AMAIR_EL1 * 2) /* Aux Memory Attr Indirection Reg */
#define c10_AMAIR1 (c10_AMAIR0 + 1)/* Aux Memory Attr Indirection Reg */
#define c14_CNTKCTL (CNTKCTL_EL1 * 2) /* Timer Control Register (PL1) */
#define cp14_DBGDSCRext (MDSCR_EL1 * 2)
#define cp14_DBGBCR0 (DBGBCR0_EL1 * 2)
#define cp14_DBGBVR0 (DBGBVR0_EL1 * 2)
#define cp14_DBGBXVR0 (cp14_DBGBVR0 + 1)
#define cp14_DBGWCR0 (DBGWCR0_EL1 * 2)
#define cp14_DBGWVR0 (DBGWVR0_EL1 * 2)
#define cp14_DBGDCCINT (MDCCINT_EL1 * 2)
#define NR_COPRO_REGS (NR_SYS_REGS * 2)
struct kvm_cpu_context {
struct kvm_regs gp_regs;
union {
u64 sys_regs[NR_SYS_REGS];
u32 copro[NR_COPRO_REGS];
};
struct kvm_vcpu *__hyp_running_vcpu;
};
typedef struct kvm_cpu_context kvm_cpu_context_t;
struct kvm_vcpu_arch {
struct kvm_cpu_context ctxt;
/* HYP configuration */
u64 hcr_el2;
u32 mdcr_el2;
/* Exception Information */
struct kvm_vcpu_fault_info fault;
/* Guest debug state */
u64 debug_flags;
/*
* We maintain more than a single set of debug registers to support
* debugging the guest from the host and to maintain separate host and
* guest state during world switches. vcpu_debug_state are the debug
* registers of the vcpu as the guest sees them. host_debug_state are
* the host registers which are saved and restored during
* world switches. external_debug_state contains the debug
* values we want to debug the guest. This is set via the
* KVM_SET_GUEST_DEBUG ioctl.
*
* debug_ptr points to the set of debug registers that should be loaded
* onto the hardware when running the guest.
*/
struct kvm_guest_debug_arch *debug_ptr;
struct kvm_guest_debug_arch vcpu_debug_state;
struct kvm_guest_debug_arch external_debug_state;
/* Pointer to host CPU context */
kvm_cpu_context_t *host_cpu_context;
struct {
/* {Break,watch}point registers */
struct kvm_guest_debug_arch regs;
/* Statistical profiling extension */
u64 pmscr_el1;
} host_debug_state;
/* VGIC state */
struct vgic_cpu vgic_cpu;
struct arch_timer_cpu timer_cpu;
struct kvm_pmu pmu;
/*
* Anything that is not used directly from assembly code goes
* here.
*/
/*
* Guest registers we preserve during guest debugging.
*
* These shadow registers are updated by the kvm_handle_sys_reg
* trap handler if the guest accesses or updates them while we
* are using guest debug.
*/
struct {
u32 mdscr_el1;
} guest_debug_preserved;
/* vcpu power-off state */
bool power_off;
/* Don't run the guest (internal implementation need) */
bool pause;
/* IO related fields */
struct kvm_decode mmio_decode;
/* Interrupt related fields */
u64 irq_lines; /* IRQ and FIQ levels */
/* Cache some mmu pages needed inside spinlock regions */
struct kvm_mmu_memory_cache mmu_page_cache;
/* Target CPU and feature flags */
int target;
DECLARE_BITMAP(features, KVM_VCPU_MAX_FEATURES);
/* Detect first run of a vcpu */
bool has_run_once;
/* Virtual SError ESR to restore when HCR_EL2.VSE is set */
u64 vsesr_el2;
};
#define vcpu_gp_regs(v) (&(v)->arch.ctxt.gp_regs)
#define vcpu_sys_reg(v,r) ((v)->arch.ctxt.sys_regs[(r)])
/*
* CP14 and CP15 live in the same array, as they are backed by the
* same system registers.
*/
#define vcpu_cp14(v,r) ((v)->arch.ctxt.copro[(r)])
#define vcpu_cp15(v,r) ((v)->arch.ctxt.copro[(r)])
#ifdef CONFIG_CPU_BIG_ENDIAN
#define vcpu_cp15_64_high(v,r) vcpu_cp15((v),(r))
#define vcpu_cp15_64_low(v,r) vcpu_cp15((v),(r) + 1)
#else
#define vcpu_cp15_64_high(v,r) vcpu_cp15((v),(r) + 1)
#define vcpu_cp15_64_low(v,r) vcpu_cp15((v),(r))
#endif
struct kvm_vm_stat {
ulong remote_tlb_flush;
};
struct kvm_vcpu_stat {
u64 halt_successful_poll;
u64 halt_attempted_poll;
u64 halt_poll_invalid;
u64 halt_wakeup;
u64 hvc_exit_stat;
u64 wfe_exit_stat;
u64 wfi_exit_stat;
u64 mmio_exit_user;
u64 mmio_exit_kernel;
u64 exits;
};
int kvm_vcpu_preferred_target(struct kvm_vcpu_init *init);
unsigned long kvm_arm_num_regs(struct kvm_vcpu *vcpu);
int kvm_arm_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices);
int kvm_arm_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
int kvm_arm_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg);
#define KVM_ARCH_WANT_MMU_NOTIFIER
int kvm_unmap_hva(struct kvm *kvm, unsigned long hva);
int kvm_unmap_hva_range(struct kvm *kvm,
unsigned long start, unsigned long end);
void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end);
int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
struct kvm_vcpu *kvm_arm_get_running_vcpu(void);
struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void);
void kvm_arm_halt_guest(struct kvm *kvm);
void kvm_arm_resume_guest(struct kvm *kvm);
u64 __kvm_call_hyp(void *hypfn, ...);
#define kvm_call_hyp(f, ...) __kvm_call_hyp(kvm_ksym_ref(f), ##__VA_ARGS__)
void force_vm_exit(const cpumask_t *mask);
void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot);
int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
int exception_index);
void handle_exit_early(struct kvm_vcpu *vcpu, struct kvm_run *run,
int exception_index);
int kvm_perf_init(void);
int kvm_perf_teardown(void);
struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr);
static inline void __cpu_init_hyp_mode(phys_addr_t pgd_ptr,
unsigned long hyp_stack_ptr,
unsigned long vector_ptr)
{
/*
arm64/cpufeature: don't use mutex in bringup path Currently, cpus_set_cap() calls static_branch_enable_cpuslocked(), which must take the jump_label mutex. We call cpus_set_cap() in the secondary bringup path, from the idle thread where interrupts are disabled. Taking a mutex in this path "is a NONO" regardless of whether it's contended, and something we must avoid. We didn't spot this until recently, as ___might_sleep() won't warn for this case until all CPUs have been brought up. This patch avoids taking the mutex in the secondary bringup path. The poking of static keys is deferred until enable_cpu_capabilities(), which runs in a suitable context on the boot CPU. To account for the static keys being set later, cpus_have_const_cap() is updated to use another static key to check whether the const cap keys have been initialised, falling back to the caps bitmap until this is the case. This means that users of cpus_have_const_cap() gain should only gain a single additional NOP in the fast path once the const caps are initialised, but should always see the current cap value. The hyp code should never dereference the caps array, since the caps are initialized before we run the module initcall to initialise hyp. A check is added to the hyp init code to document this requirement. This change will sidestep a number of issues when the upcoming hotplug locking rework is merged. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyniger <marc.zyngier@arm.com> Reviewed-by: Suzuki Poulose <suzuki.poulose@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Sewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-16 21:18:05 +07:00
* Call initialization code, and switch to the full blown HYP code.
* If the cpucaps haven't been finalized yet, something has gone very
* wrong, and hyp will crash and burn when it uses any
* cpus_have_const_cap() wrapper.
*/
arm64/cpufeature: don't use mutex in bringup path Currently, cpus_set_cap() calls static_branch_enable_cpuslocked(), which must take the jump_label mutex. We call cpus_set_cap() in the secondary bringup path, from the idle thread where interrupts are disabled. Taking a mutex in this path "is a NONO" regardless of whether it's contended, and something we must avoid. We didn't spot this until recently, as ___might_sleep() won't warn for this case until all CPUs have been brought up. This patch avoids taking the mutex in the secondary bringup path. The poking of static keys is deferred until enable_cpu_capabilities(), which runs in a suitable context on the boot CPU. To account for the static keys being set later, cpus_have_const_cap() is updated to use another static key to check whether the const cap keys have been initialised, falling back to the caps bitmap until this is the case. This means that users of cpus_have_const_cap() gain should only gain a single additional NOP in the fast path once the const caps are initialised, but should always see the current cap value. The hyp code should never dereference the caps array, since the caps are initialized before we run the module initcall to initialise hyp. A check is added to the hyp init code to document this requirement. This change will sidestep a number of issues when the upcoming hotplug locking rework is merged. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Marc Zyniger <marc.zyngier@arm.com> Reviewed-by: Suzuki Poulose <suzuki.poulose@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Christoffer Dall <christoffer.dall@linaro.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Sewior <bigeasy@linutronix.de> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-05-16 21:18:05 +07:00
BUG_ON(!static_branch_likely(&arm64_const_caps_ready));
__kvm_call_hyp((void *)pgd_ptr, hyp_stack_ptr, vector_ptr);
}
static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) {}
static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
KVM: halt_polling: provide a way to qualify wakeups during poll Some wakeups should not be considered a sucessful poll. For example on s390 I/O interrupts are usually floating, which means that _ALL_ CPUs would be considered runnable - letting all vCPUs poll all the time for transactional like workload, even if one vCPU would be enough. This can result in huge CPU usage for large guests. This patch lets architectures provide a way to qualify wakeups if they should be considered a good/bad wakeups in regard to polls. For s390 the implementation will fence of halt polling for anything but known good, single vCPU events. The s390 implementation for floating interrupts does a wakeup for one vCPU, but the interrupt will be delivered by whatever CPU checks first for a pending interrupt. We prefer the woken up CPU by marking the poll of this CPU as "good" poll. This code will also mark several other wakeup reasons like IPI or expired timers as "good". This will of course also mark some events as not sucessful. As KVM on z runs always as a 2nd level hypervisor, we prefer to not poll, unless we are really sure, though. This patch successfully limits the CPU usage for cases like uperf 1byte transactional ping pong workload or wakeup heavy workload like OLTP while still providing a proper speedup. This also introduced a new vcpu stat "halt_poll_no_tuning" that marks wakeups that are considered not good for polling. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Radim Krčmář <rkrcmar@redhat.com> (for an earlier version) Cc: David Matlack <dmatlack@google.com> Cc: Wanpeng Li <kernellwp@gmail.com> [Rename config symbol. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-05-13 17:16:35 +07:00
static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
void kvm_arm_init_debug(void);
void kvm_arm_setup_debug(struct kvm_vcpu *vcpu);
void kvm_arm_clear_debug(struct kvm_vcpu *vcpu);
void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu);
bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run);
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
static inline void __cpu_init_stage2(void)
{
u32 parange = kvm_call_hyp(__init_stage2_translation);
WARN_ONCE(parange < 40,
"PARange is %d bits, unsupported configuration!", parange);
}
arm64/sve: KVM: Prevent guests from using SVE Until KVM has full SVE support, guests must not be allowed to execute SVE instructions. This patch enables the necessary traps, and also ensures that the traps are disabled again on exit from the guest so that the host can still use SVE if it wants to. On guest exit, high bits of the SVE Zn registers may have been clobbered as a side-effect the execution of FPSIMD instructions in the guest. The existing KVM host FPSIMD restore code is not sufficient to restore these bits, so this patch explicitly marks the CPU as not containing cached vector state for any task, thus forcing a reload on the next return to userspace. This is an interim measure, in advance of adding full SVE awareness to KVM. This marking of cached vector state in the CPU as invalid is done using __this_cpu_write(fpsimd_last_state, NULL) in fpsimd.c. Due to the repeated use of this rather obscure operation, it makes sense to factor it out as a separate helper with a clearer name. This patch factors it out as fpsimd_flush_cpu_state(), and ports all callers to use it. As a side effect of this refactoring, a this_cpu_write() in fpsimd_cpu_pm_notifier() is changed to __this_cpu_write(). This should be fine, since cpu_pm_enter() is supposed to be called only with interrupts disabled. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-31 22:51:16 +07:00
/*
* All host FP/SIMD state is restored on guest exit, so nothing needs
* doing here except in the SVE case:
*/
static inline void kvm_fpsimd_flush_cpu_state(void)
{
if (system_supports_sve())
sve_flush_cpu_state();
}
static inline void kvm_arm_vhe_guest_enter(void)
{
local_daif_mask();
}
static inline void kvm_arm_vhe_guest_exit(void)
{
local_daif_restore(DAIF_PROCCTX_NOIRQ);
}
#endif /* __ARM64_KVM_HOST_H__ */