Skip to content

Commit

Permalink
Merge tag 'kvmarm-fixes-for-4.18-1' of git://git.kernel.org/pub/scm/l…
Browse files Browse the repository at this point in the history
…inux/kernel/git/kvmarm/kvmarm

KVM/arm fixes for 4.18, take #1

- Lazy FPSIMD switching fixes
- Really disable compat ioctls on architectures that don't want it
- Disable compat on arm64 (it was never implemented...)
- Rely on architectural requirements for GICV on GICv3
- Detect bad alignments in unmap_stage2_range
  • Loading branch information
rkrcmar committed Jun 22, 2018
2 parents ce397d2 + 37b65db commit 5f9077c
Show file tree
Hide file tree
Showing 7 changed files with 51 additions and 25 deletions.
1 change: 1 addition & 0 deletions arch/arm64/include/asm/kvm_host.h
Original file line number Diff line number Diff line change
Expand Up @@ -306,6 +306,7 @@ struct kvm_vcpu_arch {
#define KVM_ARM64_FP_ENABLED (1 << 1) /* guest FP regs loaded */
#define KVM_ARM64_FP_HOST (1 << 2) /* host FP regs loaded */
#define KVM_ARM64_HOST_SVE_IN_USE (1 << 3) /* backup for host TIF_SVE */
#define KVM_ARM64_HOST_SVE_ENABLED (1 << 4) /* SVE enabled for EL0 */

#define vcpu_gp_regs(v) (&(v)->arch.ctxt.gp_regs)

Expand Down
11 changes: 11 additions & 0 deletions arch/arm64/include/asm/sysreg.h
Original file line number Diff line number Diff line change
Expand Up @@ -728,6 +728,17 @@ asm(
asm volatile("msr_s " __stringify(r) ", %x0" : : "rZ" (__val)); \
} while (0)

/*
* Modify bits in a sysreg. Bits in the clear mask are zeroed, then bits in the
* set mask are set. Other bits are left as-is.
*/
#define sysreg_clear_set(sysreg, clear, set) do { \
u64 __scs_val = read_sysreg(sysreg); \
u64 __scs_new = (__scs_val & ~(u64)(clear)) | (set); \
if (__scs_new != __scs_val) \
write_sysreg(__scs_new, sysreg); \
} while (0)

static inline void config_sctlr_el1(u32 clear, u32 set)
{
u32 val;
Expand Down
36 changes: 27 additions & 9 deletions arch/arm64/kvm/fpsimd.c
Original file line number Diff line number Diff line change
Expand Up @@ -5,13 +5,14 @@
* Copyright 2018 Arm Limited
* Author: Dave Martin <[email protected]>
*/
#include <linux/bottom_half.h>
#include <linux/irqflags.h>
#include <linux/sched.h>
#include <linux/thread_info.h>
#include <linux/kvm_host.h>
#include <asm/kvm_asm.h>
#include <asm/kvm_host.h>
#include <asm/kvm_mmu.h>
#include <asm/sysreg.h>

/*
* Called on entry to KVM_RUN unless this vcpu previously ran at least
Expand Down Expand Up @@ -61,10 +62,16 @@ void kvm_arch_vcpu_load_fp(struct kvm_vcpu *vcpu)
{
BUG_ON(!current->mm);

vcpu->arch.flags &= ~(KVM_ARM64_FP_ENABLED | KVM_ARM64_HOST_SVE_IN_USE);
vcpu->arch.flags &= ~(KVM_ARM64_FP_ENABLED |
KVM_ARM64_HOST_SVE_IN_USE |
KVM_ARM64_HOST_SVE_ENABLED);
vcpu->arch.flags |= KVM_ARM64_FP_HOST;

if (test_thread_flag(TIF_SVE))
vcpu->arch.flags |= KVM_ARM64_HOST_SVE_IN_USE;

if (read_sysreg(cpacr_el1) & CPACR_EL1_ZEN_EL0EN)
vcpu->arch.flags |= KVM_ARM64_HOST_SVE_ENABLED;
}

/*
Expand Down Expand Up @@ -92,19 +99,30 @@ void kvm_arch_vcpu_ctxsync_fp(struct kvm_vcpu *vcpu)
*/
void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu)
{
local_bh_disable();
unsigned long flags;

update_thread_flag(TIF_SVE,
vcpu->arch.flags & KVM_ARM64_HOST_SVE_IN_USE);
local_irq_save(flags);

if (vcpu->arch.flags & KVM_ARM64_FP_ENABLED) {
/* Clean guest FP state to memory and invalidate cpu view */
fpsimd_save();
fpsimd_flush_cpu_state();
} else if (!test_thread_flag(TIF_FOREIGN_FPSTATE)) {
/* Ensure user trap controls are correctly restored */
fpsimd_bind_task_to_cpu();
} else if (system_supports_sve()) {
/*
* The FPSIMD/SVE state in the CPU has not been touched, and we
* have SVE (and VHE): CPACR_EL1 (alias CPTR_EL2) has been
* reset to CPACR_EL1_DEFAULT by the Hyp code, disabling SVE
* for EL0. To avoid spurious traps, restore the trap state
* seen by kvm_arch_vcpu_load_fp():
*/
if (vcpu->arch.flags & KVM_ARM64_HOST_SVE_ENABLED)
sysreg_clear_set(CPACR_EL1, 0, CPACR_EL1_ZEN_EL0EN);
else
sysreg_clear_set(CPACR_EL1, CPACR_EL1_ZEN_EL0EN, 0);
}

local_bh_enable();
update_thread_flag(TIF_SVE,
vcpu->arch.flags & KVM_ARM64_HOST_SVE_IN_USE);

local_irq_restore(flags);
}
2 changes: 1 addition & 1 deletion virt/kvm/Kconfig
Original file line number Diff line number Diff line change
Expand Up @@ -47,7 +47,7 @@ config KVM_GENERIC_DIRTYLOG_READ_PROTECT

config KVM_COMPAT
def_bool y
depends on KVM && COMPAT && !S390
depends on KVM && COMPAT && !(S390 || ARM64)

config HAVE_KVM_IRQ_BYPASS
bool
Expand Down
2 changes: 2 additions & 0 deletions virt/kvm/arm/mmu.c
Original file line number Diff line number Diff line change
Expand Up @@ -297,6 +297,8 @@ static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
phys_addr_t next;

assert_spin_locked(&kvm->mmu_lock);
WARN_ON(size & ~PAGE_MASK);

pgd = kvm->arch.pgd + stage2_pgd_index(addr);
do {
/*
Expand Down
5 changes: 0 additions & 5 deletions virt/kvm/arm/vgic/vgic-v3.c
Original file line number Diff line number Diff line change
Expand Up @@ -617,11 +617,6 @@ int vgic_v3_probe(const struct gic_kvm_info *info)
pr_warn("GICV physical address 0x%llx not page aligned\n",
(unsigned long long)info->vcpu.start);
kvm_vgic_global_state.vcpu_base = 0;
} else if (!PAGE_ALIGNED(resource_size(&info->vcpu))) {
pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
(unsigned long long)resource_size(&info->vcpu),
PAGE_SIZE);
kvm_vgic_global_state.vcpu_base = 0;
} else {
kvm_vgic_global_state.vcpu_base = info->vcpu.start;
kvm_vgic_global_state.can_emulate_gicv2 = true;
Expand Down
19 changes: 9 additions & 10 deletions virt/kvm/kvm_main.c
Original file line number Diff line number Diff line change
Expand Up @@ -116,6 +116,11 @@ static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
#ifdef CONFIG_KVM_COMPAT
static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
unsigned long arg);
#define KVM_COMPAT(c) .compat_ioctl = (c)
#else
static long kvm_no_compat_ioctl(struct file *file, unsigned int ioctl,
unsigned long arg) { return -EINVAL; }
#define KVM_COMPAT(c) .compat_ioctl = kvm_no_compat_ioctl
#endif
static int hardware_enable_all(void);
static void hardware_disable_all(void);
Expand Down Expand Up @@ -2396,11 +2401,9 @@ static int kvm_vcpu_release(struct inode *inode, struct file *filp)
static struct file_operations kvm_vcpu_fops = {
.release = kvm_vcpu_release,
.unlocked_ioctl = kvm_vcpu_ioctl,
#ifdef CONFIG_KVM_COMPAT
.compat_ioctl = kvm_vcpu_compat_ioctl,
#endif
.mmap = kvm_vcpu_mmap,
.llseek = noop_llseek,
KVM_COMPAT(kvm_vcpu_compat_ioctl),
};

/*
Expand Down Expand Up @@ -2824,10 +2827,8 @@ static int kvm_device_release(struct inode *inode, struct file *filp)

static const struct file_operations kvm_device_fops = {
.unlocked_ioctl = kvm_device_ioctl,
#ifdef CONFIG_KVM_COMPAT
.compat_ioctl = kvm_device_ioctl,
#endif
.release = kvm_device_release,
KVM_COMPAT(kvm_device_ioctl),
};

struct kvm_device *kvm_device_from_filp(struct file *filp)
Expand Down Expand Up @@ -3165,10 +3166,8 @@ static long kvm_vm_compat_ioctl(struct file *filp,
static struct file_operations kvm_vm_fops = {
.release = kvm_vm_release,
.unlocked_ioctl = kvm_vm_ioctl,
#ifdef CONFIG_KVM_COMPAT
.compat_ioctl = kvm_vm_compat_ioctl,
#endif
.llseek = noop_llseek,
KVM_COMPAT(kvm_vm_compat_ioctl),
};

static int kvm_dev_ioctl_create_vm(unsigned long type)
Expand Down Expand Up @@ -3259,8 +3258,8 @@ static long kvm_dev_ioctl(struct file *filp,

static struct file_operations kvm_chardev_ops = {
.unlocked_ioctl = kvm_dev_ioctl,
.compat_ioctl = kvm_dev_ioctl,
.llseek = noop_llseek,
KVM_COMPAT(kvm_dev_ioctl),
};

static struct miscdevice kvm_dev = {
Expand Down

0 comments on commit 5f9077c

Please sign in to comment.