| Message ID | 1436286603-15192-9-git-send-email-alex.bennee@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Jul 07, 2015 at 05:30:00PM +0100, Alex Bennée wrote: > This introduces a level of indirection for the debug registers. Instead > of using the sys_regs[] directly we store registers in a structure in > the vcpu. The new kvm_arm_reset_debug_ptr() sets the debug ptr to the > guest context. > > Because we no longer give the sys_regs offset for the sys_reg_desc->reg > field, but instead the index into a debug-specific struct we need to > add a number of additional trap functions for each register. Also as the > generic generic user-space access code no longer works we have nit: you have generic twice > introduced a new pair of function pointers to the sys_reg_desc structure > to override the generic code when needed. > > Signed-off-by: Alex Bennée <alex.bennee@linaro.org> > Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Thanks, -Christoffer > --- > v6: > - fix up some ws issues > - correct clobber info > - re-word commentary in kvm_host.h > - fix endian access issues for aarch32 fields > - revert all KVM_GET/SET_ONE_REG to 64bit (also see ABI update) > v7 > - new fn kvm_arm_reset_debug_ptr(), stubbed for arm > - split trap fns into bcr,bvr,bcr,wvr and wxvr > - add set/get fns to sys_regs_desc > - reg_to_dbg/dbg_to_reg helpers for 32bit support > v8 > - rm #if 0 left over from re-factor > - re-word reset_ptr comment > - fix inadvertent whitespace changes > - rename get/set to get_user/set_user > - update commit wording > - re-factor dbg_to_reg/reg_to_dbg > - add newlines to keep checkpatch happy > - ensure 63:32 of debug registers untouched by aarch32 > --- > arch/arm/include/asm/kvm_host.h | 1 + > arch/arm/kvm/arm.c | 2 + > arch/arm64/include/asm/kvm_asm.h | 24 ++-- > arch/arm64/include/asm/kvm_host.h | 17 ++- > arch/arm64/kernel/asm-offsets.c | 6 + > arch/arm64/kvm/debug.c | 9 ++ > arch/arm64/kvm/hyp.S | 24 ++-- > arch/arm64/kvm/sys_regs.c | 274 +++++++++++++++++++++++++++++++++++--- > arch/arm64/kvm/sys_regs.h | 6 + > 9 files changed, 316 insertions(+), 47 deletions(-) > > diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h > index 746c0c69..825c337 100644 > --- a/arch/arm/include/asm/kvm_host.h > +++ b/arch/arm/include/asm/kvm_host.h > @@ -239,5 +239,6 @@ static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} > static inline void kvm_arm_init_debug(void) {} > static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} > static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} > +static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {} > > #endif /* __ARM_KVM_HOST_H__ */ > diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c > index af60e6f..525473f 100644 > --- a/arch/arm/kvm/arm.c > +++ b/arch/arm/kvm/arm.c > @@ -279,6 +279,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) > /* Set up the timer */ > kvm_timer_vcpu_init(vcpu); > > + kvm_arm_reset_debug_ptr(vcpu); > + > return 0; > } > > diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h > index d6b507e..e997404 100644 > --- a/arch/arm64/include/asm/kvm_asm.h > +++ b/arch/arm64/include/asm/kvm_asm.h > @@ -46,24 +46,16 @@ > #define CNTKCTL_EL1 20 /* Timer Control Register (EL1) */ > #define PAR_EL1 21 /* Physical Address Register */ > #define MDSCR_EL1 22 /* Monitor Debug System Control Register */ > -#define DBGBCR0_EL1 23 /* Debug Breakpoint Control Registers (0-15) */ > -#define DBGBCR15_EL1 38 > -#define DBGBVR0_EL1 39 /* Debug Breakpoint Value Registers (0-15) */ > -#define DBGBVR15_EL1 54 > -#define DBGWCR0_EL1 55 /* Debug Watchpoint Control Registers (0-15) */ > -#define DBGWCR15_EL1 70 > -#define DBGWVR0_EL1 71 /* Debug Watchpoint Value Registers (0-15) */ > -#define DBGWVR15_EL1 86 > -#define MDCCINT_EL1 87 /* Monitor Debug Comms Channel Interrupt Enable Reg */ > +#define MDCCINT_EL1 23 /* Monitor Debug Comms Channel Interrupt Enable Reg */ > > /* 32bit specific registers. Keep them at the end of the range */ > -#define DACR32_EL2 88 /* Domain Access Control Register */ > -#define IFSR32_EL2 89 /* Instruction Fault Status Register */ > -#define FPEXC32_EL2 90 /* Floating-Point Exception Control Register */ > -#define DBGVCR32_EL2 91 /* Debug Vector Catch Register */ > -#define TEECR32_EL1 92 /* ThumbEE Configuration Register */ > -#define TEEHBR32_EL1 93 /* ThumbEE Handler Base Register */ > -#define NR_SYS_REGS 94 > +#define DACR32_EL2 24 /* Domain Access Control Register */ > +#define IFSR32_EL2 25 /* Instruction Fault Status Register */ > +#define FPEXC32_EL2 26 /* Floating-Point Exception Control Register */ > +#define DBGVCR32_EL2 27 /* Debug Vector Catch Register */ > +#define TEECR32_EL1 28 /* ThumbEE Configuration Register */ > +#define TEEHBR32_EL1 29 /* ThumbEE Handler Base Register */ > +#define NR_SYS_REGS 30 > > /* 32bit mapping */ > #define c0_MPIDR (MPIDR_EL1 * 2) /* MultiProcessor ID Register */ > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > index e2db6a6..461d288 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -108,11 +108,25 @@ struct kvm_vcpu_arch { > /* Exception Information */ > struct kvm_vcpu_fault_info fault; > > - /* Debug state */ > + /* 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. > + * > + * 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; > + > /* Pointer to host CPU context */ > kvm_cpu_context_t *host_cpu_context; > + struct kvm_guest_debug_arch host_debug_state; > > /* VGIC state */ > struct vgic_cpu vgic_cpu; > @@ -265,5 +279,6 @@ static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} > 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); > > #endif /* __ARM64_KVM_HOST_H__ */ > diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c > index dfb25a2..1a8e97c 100644 > --- a/arch/arm64/kernel/asm-offsets.c > +++ b/arch/arm64/kernel/asm-offsets.c > @@ -116,10 +116,16 @@ int main(void) > DEFINE(VCPU_FAR_EL2, offsetof(struct kvm_vcpu, arch.fault.far_el2)); > DEFINE(VCPU_HPFAR_EL2, offsetof(struct kvm_vcpu, arch.fault.hpfar_el2)); > DEFINE(VCPU_DEBUG_FLAGS, offsetof(struct kvm_vcpu, arch.debug_flags)); > + DEFINE(VCPU_DEBUG_PTR, offsetof(struct kvm_vcpu, arch.debug_ptr)); > + DEFINE(DEBUG_BCR, offsetof(struct kvm_guest_debug_arch, dbg_bcr)); > + DEFINE(DEBUG_BVR, offsetof(struct kvm_guest_debug_arch, dbg_bvr)); > + DEFINE(DEBUG_WCR, offsetof(struct kvm_guest_debug_arch, dbg_wcr)); > + DEFINE(DEBUG_WVR, offsetof(struct kvm_guest_debug_arch, dbg_wvr)); > DEFINE(VCPU_HCR_EL2, offsetof(struct kvm_vcpu, arch.hcr_el2)); > DEFINE(VCPU_MDCR_EL2, offsetof(struct kvm_vcpu, arch.mdcr_el2)); > DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines)); > DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu, arch.host_cpu_context)); > + DEFINE(VCPU_HOST_DEBUG_STATE, offsetof(struct kvm_vcpu, arch.host_debug_state)); > DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl)); > DEFINE(VCPU_TIMER_CNTV_CVAL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval)); > DEFINE(KVM_TIMER_CNTVOFF, offsetof(struct kvm, arch.timer.cntvoff)); > diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c > index d439eb8..e0947b7 100644 > --- a/arch/arm64/kvm/debug.c > +++ b/arch/arm64/kvm/debug.c > @@ -67,6 +67,15 @@ void kvm_arm_init_debug(void) > } > > /** > + * kvm_arm_reset_debug_ptr - reset the debug ptr to point to the vcpu state > + */ > + > +void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) > +{ > + vcpu->arch.debug_ptr = &vcpu->arch.vcpu_debug_state; > +} > + > +/** > * kvm_arm_setup_debug - set up debug related stuff > * > * @vcpu: the vcpu pointer > diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S > index 77c08df..f56e93f 100644 > --- a/arch/arm64/kvm/hyp.S > +++ b/arch/arm64/kvm/hyp.S > @@ -600,6 +600,7 @@ __restore_sysregs: > /* Save debug state */ > __save_debug: > // x2: ptr to CPU context > + // x3: ptr to debug reg struct > // x4/x5/x6-22/x24-26: trashed > > mrs x26, id_aa64dfr0_el1 > @@ -610,15 +611,15 @@ __save_debug: > sub w25, w26, w25 // How many WPs to skip > > mov x5, x24 > - add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) > + add x4, x3, #DEBUG_BCR > save_debug dbgbcr > - add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) > + add x4, x3, #DEBUG_BVR > save_debug dbgbvr > > mov x5, x25 > - add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) > + add x4, x3, #DEBUG_WCR > save_debug dbgwcr > - add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) > + add x4, x3, #DEBUG_WVR > save_debug dbgwvr > > mrs x21, mdccint_el1 > @@ -628,6 +629,7 @@ __save_debug: > /* Restore debug state */ > __restore_debug: > // x2: ptr to CPU context > + // x3: ptr to debug reg struct > // x4/x5/x6-22/x24-26: trashed > > mrs x26, id_aa64dfr0_el1 > @@ -638,15 +640,15 @@ __restore_debug: > sub w25, w26, w25 // How many WPs to skip > > mov x5, x24 > - add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) > + add x4, x3, #DEBUG_BCR > restore_debug dbgbcr > - add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) > + add x4, x3, #DEBUG_BVR > restore_debug dbgbvr > > mov x5, x25 > - add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) > + add x4, x3, #DEBUG_WCR > restore_debug dbgwcr > - add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) > + add x4, x3, #DEBUG_WVR > restore_debug dbgwvr > > ldr x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] > @@ -686,6 +688,7 @@ ENTRY(__kvm_vcpu_run) > bl __save_sysregs > > compute_debug_state 1f > + add x3, x0, #VCPU_HOST_DEBUG_STATE > bl __save_debug > 1: > activate_traps > @@ -701,6 +704,8 @@ ENTRY(__kvm_vcpu_run) > bl __restore_fpsimd > > skip_debug_state x3, 1f > + ldr x3, [x0, #VCPU_DEBUG_PTR] > + kern_hyp_va x3 > bl __restore_debug > 1: > restore_guest_32bit_state > @@ -721,6 +726,8 @@ __kvm_vcpu_return: > bl __save_sysregs > > skip_debug_state x3, 1f > + ldr x3, [x0, #VCPU_DEBUG_PTR] > + kern_hyp_va x3 > bl __save_debug > 1: > save_guest_32bit_state > @@ -743,6 +750,7 @@ __kvm_vcpu_return: > // already been saved. Note that we nuke the whole 64bit word. > // If we ever add more flags, we'll have to be more careful... > str xzr, [x0, #VCPU_DEBUG_FLAGS] > + add x3, x0, #VCPU_HOST_DEBUG_STATE > bl __restore_debug > 1: > restore_host_regs > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index c370b40..158bae7 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -211,6 +211,203 @@ static bool trap_debug_regs(struct kvm_vcpu *vcpu, > return true; > } > > +/* > + * reg_to_dbg/dbg_to_reg > + * > + * A 32 bit write to a debug register leave top bits alone > + * A 32 bit read from a debug register only returns the bottom bits > + * > + * All writes will set the KVM_ARM64_DEBUG_DIRTY flag to ensure the > + * hyp.S code switches between host and guest values in future. > + */ > +static inline void reg_to_dbg(struct kvm_vcpu *vcpu, > + const struct sys_reg_params *p, > + u64 *dbg_reg) > +{ > + u64 val = *vcpu_reg(vcpu, p->Rt); > + > + if (p->is_32bit) { > + val &= 0xffffffffUL; > + val |= ((*dbg_reg >> 32) << 32); > + } > + > + *dbg_reg = val; > + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; > +} > + > +static inline void dbg_to_reg(struct kvm_vcpu *vcpu, > + const struct sys_reg_params *p, > + u64 *dbg_reg) > +{ > + u64 val = *dbg_reg; > + > + if (p->is_32bit) > + val &= 0xffffffffUL; > + > + *vcpu_reg(vcpu, p->Rt) = val; > +} > + > +static inline bool trap_bvr(struct kvm_vcpu *vcpu, > + const struct sys_reg_params *p, > + const struct sys_reg_desc *rd) > +{ > + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; > + > + if (p->is_write) > + reg_to_dbg(vcpu, p, dbg_reg); > + else > + dbg_to_reg(vcpu, p, dbg_reg); > + > + return true; > +} > + > +static int set_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; > + > + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + return 0; > +} > + > +static int get_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; > + > + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + return 0; > +} > + > +static inline void reset_bvr(struct kvm_vcpu *vcpu, > + const struct sys_reg_desc *rd) > +{ > + vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg] = rd->val; > +} > + > +static inline bool trap_bcr(struct kvm_vcpu *vcpu, > + const struct sys_reg_params *p, > + const struct sys_reg_desc *rd) > +{ > + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; > + > + if (p->is_write) > + reg_to_dbg(vcpu, p, dbg_reg); > + else > + dbg_to_reg(vcpu, p, dbg_reg); > + > + return true; > +} > + > +static int set_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; > + > + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + > + return 0; > +} > + > +static int get_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; > + > + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + return 0; > +} > + > +static inline void reset_bcr(struct kvm_vcpu *vcpu, > + const struct sys_reg_desc *rd) > +{ > + vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg] = rd->val; > +} > + > +static inline bool trap_wvr(struct kvm_vcpu *vcpu, > + const struct sys_reg_params *p, > + const struct sys_reg_desc *rd) > +{ > + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; > + > + if (p->is_write) > + reg_to_dbg(vcpu, p, dbg_reg); > + else > + dbg_to_reg(vcpu, p, dbg_reg); > + > + return true; > +} > + > +static int set_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; > + > + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + return 0; > +} > + > +static int get_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; > + > + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + return 0; > +} > + > +static inline void reset_wvr(struct kvm_vcpu *vcpu, > + const struct sys_reg_desc *rd) > +{ > + vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg] = rd->val; > +} > + > +static inline bool trap_wcr(struct kvm_vcpu *vcpu, > + const struct sys_reg_params *p, > + const struct sys_reg_desc *rd) > +{ > + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; > + > + if (p->is_write) > + reg_to_dbg(vcpu, p, dbg_reg); > + else > + dbg_to_reg(vcpu, p, dbg_reg); > + > + return true; > +} > + > +static int set_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; > + > + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + return 0; > +} > + > +static int get_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr) > +{ > + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; > + > + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) > + return -EFAULT; > + return 0; > +} > + > +static inline void reset_wcr(struct kvm_vcpu *vcpu, > + const struct sys_reg_desc *rd) > +{ > + vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg] = rd->val; > +} > + > static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) > { > u64 amair; > @@ -240,16 +437,16 @@ static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) > #define DBG_BCR_BVR_WCR_WVR_EL1(n) \ > /* DBGBVRn_EL1 */ \ > { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b100), \ > - trap_debug_regs, reset_val, (DBGBVR0_EL1 + (n)), 0 }, \ > + trap_bvr, reset_bvr, n, 0, get_bvr, set_bvr }, \ > /* DBGBCRn_EL1 */ \ > { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b101), \ > - trap_debug_regs, reset_val, (DBGBCR0_EL1 + (n)), 0 }, \ > + trap_bcr, reset_bcr, n, 0, get_bcr, set_bcr }, \ > /* DBGWVRn_EL1 */ \ > { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b110), \ > - trap_debug_regs, reset_val, (DBGWVR0_EL1 + (n)), 0 }, \ > + trap_wvr, reset_wvr, n, 0, get_wvr, set_wvr }, \ > /* DBGWCRn_EL1 */ \ > { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b111), \ > - trap_debug_regs, reset_val, (DBGWCR0_EL1 + (n)), 0 } > + trap_wcr, reset_wcr, n, 0, get_wcr, set_wcr } > > /* > * Architected system registers. > @@ -516,28 +713,55 @@ static bool trap_debug32(struct kvm_vcpu *vcpu, > return true; > } > > -#define DBG_BCR_BVR_WCR_WVR(n) \ > - /* DBGBVRn */ \ > - { Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_debug32, \ > - NULL, (cp14_DBGBVR0 + (n) * 2) }, \ > - /* DBGBCRn */ \ > - { Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_debug32, \ > - NULL, (cp14_DBGBCR0 + (n) * 2) }, \ > - /* DBGWVRn */ \ > - { Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_debug32, \ > - NULL, (cp14_DBGWVR0 + (n) * 2) }, \ > - /* DBGWCRn */ \ > - { Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_debug32, \ > - NULL, (cp14_DBGWCR0 + (n) * 2) } > - > -#define DBGBXVR(n) \ > - { Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_debug32, \ > - NULL, cp14_DBGBXVR0 + n * 2 } > +/* AArch32 debug register mappings > + * > + * AArch32 DBGBVRn is mapped to DBGBVRn_EL1[31:0] > + * AArch32 DBGBXVRn is mapped to DBGBVRn_EL1[63:32] > + * > + * All control registers and watchpoint value registers are mapped to > + * the lower 32 bits of their AArch64 equivalents. We share the trap > + * handlers with the above AArch64 code which checks what mode the > + * system is in. > + */ > + > +static inline bool trap_xvr(struct kvm_vcpu *vcpu, > + const struct sys_reg_params *p, > + const struct sys_reg_desc *rd) > +{ > + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; > + > + if (p->is_write) { > + u64 val = *dbg_reg; > + > + val &= 0xffffffffUL; > + val |= *vcpu_reg(vcpu, p->Rt) << 32; > + *dbg_reg = val; > + > + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; > + } else { > + *vcpu_reg(vcpu, p->Rt) = *dbg_reg >> 32; > + } > + > + return true; > +} > + > +#define DBG_BCR_BVR_WCR_WVR(n) \ > + /* DBGBVRn */ \ > + { Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_bvr, NULL, n }, \ > + /* DBGBCRn */ \ > + { Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_bcr, NULL, n }, \ > + /* DBGWVRn */ \ > + { Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_wvr, NULL, n }, \ > + /* DBGWCRn */ \ > + { Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_wcr, NULL, n } > + > +#define DBGBXVR(n) \ > + { Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_xvr, NULL, n } > > /* > * Trapped cp14 registers. We generally ignore most of the external > * debug, on the principle that they don't really make sense to a > - * guest. Revisit this one day, whould this principle change. > + * guest. Revisit this one day, would this principle change. > */ > static const struct sys_reg_desc cp14_regs[] = { > /* DBGIDR */ > @@ -1303,6 +1527,9 @@ int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg > if (!r) > return get_invariant_sys_reg(reg->id, uaddr); > > + if (r->get_user) > + return (r->get_user)(vcpu, r, reg, uaddr); > + > return reg_to_user(uaddr, &vcpu_sys_reg(vcpu, r->reg), reg->id); > } > > @@ -1321,6 +1548,9 @@ int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg > if (!r) > return set_invariant_sys_reg(reg->id, uaddr); > > + if (r->set_user) > + return (r->set_user)(vcpu, r, reg, uaddr); > + > return reg_from_user(&vcpu_sys_reg(vcpu, r->reg), uaddr, reg->id); > } > > diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h > index d411e25..eaa324e 100644 > --- a/arch/arm64/kvm/sys_regs.h > +++ b/arch/arm64/kvm/sys_regs.h > @@ -55,6 +55,12 @@ struct sys_reg_desc { > > /* Value (usually reset value) */ > u64 val; > + > + /* Custom get/set_user functions, fallback to generic if NULL */ > + int (*get_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr); > + int (*set_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, > + const struct kvm_one_reg *reg, void __user *uaddr); > }; > > static inline void print_sys_reg_instr(const struct sys_reg_params *p) > -- > 2.4.5 >
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 746c0c69..825c337 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -239,5 +239,6 @@ static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} static inline void kvm_arm_init_debug(void) {} static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} +static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {} #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index af60e6f..525473f 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -279,6 +279,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) /* Set up the timer */ kvm_timer_vcpu_init(vcpu); + kvm_arm_reset_debug_ptr(vcpu); + return 0; } diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index d6b507e..e997404 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -46,24 +46,16 @@ #define CNTKCTL_EL1 20 /* Timer Control Register (EL1) */ #define PAR_EL1 21 /* Physical Address Register */ #define MDSCR_EL1 22 /* Monitor Debug System Control Register */ -#define DBGBCR0_EL1 23 /* Debug Breakpoint Control Registers (0-15) */ -#define DBGBCR15_EL1 38 -#define DBGBVR0_EL1 39 /* Debug Breakpoint Value Registers (0-15) */ -#define DBGBVR15_EL1 54 -#define DBGWCR0_EL1 55 /* Debug Watchpoint Control Registers (0-15) */ -#define DBGWCR15_EL1 70 -#define DBGWVR0_EL1 71 /* Debug Watchpoint Value Registers (0-15) */ -#define DBGWVR15_EL1 86 -#define MDCCINT_EL1 87 /* Monitor Debug Comms Channel Interrupt Enable Reg */ +#define MDCCINT_EL1 23 /* Monitor Debug Comms Channel Interrupt Enable Reg */ /* 32bit specific registers. Keep them at the end of the range */ -#define DACR32_EL2 88 /* Domain Access Control Register */ -#define IFSR32_EL2 89 /* Instruction Fault Status Register */ -#define FPEXC32_EL2 90 /* Floating-Point Exception Control Register */ -#define DBGVCR32_EL2 91 /* Debug Vector Catch Register */ -#define TEECR32_EL1 92 /* ThumbEE Configuration Register */ -#define TEEHBR32_EL1 93 /* ThumbEE Handler Base Register */ -#define NR_SYS_REGS 94 +#define DACR32_EL2 24 /* Domain Access Control Register */ +#define IFSR32_EL2 25 /* Instruction Fault Status Register */ +#define FPEXC32_EL2 26 /* Floating-Point Exception Control Register */ +#define DBGVCR32_EL2 27 /* Debug Vector Catch Register */ +#define TEECR32_EL1 28 /* ThumbEE Configuration Register */ +#define TEEHBR32_EL1 29 /* ThumbEE Handler Base Register */ +#define NR_SYS_REGS 30 /* 32bit mapping */ #define c0_MPIDR (MPIDR_EL1 * 2) /* MultiProcessor ID Register */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index e2db6a6..461d288 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -108,11 +108,25 @@ struct kvm_vcpu_arch { /* Exception Information */ struct kvm_vcpu_fault_info fault; - /* Debug state */ + /* 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. + * + * 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; + /* Pointer to host CPU context */ kvm_cpu_context_t *host_cpu_context; + struct kvm_guest_debug_arch host_debug_state; /* VGIC state */ struct vgic_cpu vgic_cpu; @@ -265,5 +279,6 @@ static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {} 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); #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c index dfb25a2..1a8e97c 100644 --- a/arch/arm64/kernel/asm-offsets.c +++ b/arch/arm64/kernel/asm-offsets.c @@ -116,10 +116,16 @@ int main(void) DEFINE(VCPU_FAR_EL2, offsetof(struct kvm_vcpu, arch.fault.far_el2)); DEFINE(VCPU_HPFAR_EL2, offsetof(struct kvm_vcpu, arch.fault.hpfar_el2)); DEFINE(VCPU_DEBUG_FLAGS, offsetof(struct kvm_vcpu, arch.debug_flags)); + DEFINE(VCPU_DEBUG_PTR, offsetof(struct kvm_vcpu, arch.debug_ptr)); + DEFINE(DEBUG_BCR, offsetof(struct kvm_guest_debug_arch, dbg_bcr)); + DEFINE(DEBUG_BVR, offsetof(struct kvm_guest_debug_arch, dbg_bvr)); + DEFINE(DEBUG_WCR, offsetof(struct kvm_guest_debug_arch, dbg_wcr)); + DEFINE(DEBUG_WVR, offsetof(struct kvm_guest_debug_arch, dbg_wvr)); DEFINE(VCPU_HCR_EL2, offsetof(struct kvm_vcpu, arch.hcr_el2)); DEFINE(VCPU_MDCR_EL2, offsetof(struct kvm_vcpu, arch.mdcr_el2)); DEFINE(VCPU_IRQ_LINES, offsetof(struct kvm_vcpu, arch.irq_lines)); DEFINE(VCPU_HOST_CONTEXT, offsetof(struct kvm_vcpu, arch.host_cpu_context)); + DEFINE(VCPU_HOST_DEBUG_STATE, offsetof(struct kvm_vcpu, arch.host_debug_state)); DEFINE(VCPU_TIMER_CNTV_CTL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_ctl)); DEFINE(VCPU_TIMER_CNTV_CVAL, offsetof(struct kvm_vcpu, arch.timer_cpu.cntv_cval)); DEFINE(KVM_TIMER_CNTVOFF, offsetof(struct kvm, arch.timer.cntvoff)); diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c index d439eb8..e0947b7 100644 --- a/arch/arm64/kvm/debug.c +++ b/arch/arm64/kvm/debug.c @@ -67,6 +67,15 @@ void kvm_arm_init_debug(void) } /** + * kvm_arm_reset_debug_ptr - reset the debug ptr to point to the vcpu state + */ + +void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) +{ + vcpu->arch.debug_ptr = &vcpu->arch.vcpu_debug_state; +} + +/** * kvm_arm_setup_debug - set up debug related stuff * * @vcpu: the vcpu pointer diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S index 77c08df..f56e93f 100644 --- a/arch/arm64/kvm/hyp.S +++ b/arch/arm64/kvm/hyp.S @@ -600,6 +600,7 @@ __restore_sysregs: /* Save debug state */ __save_debug: // x2: ptr to CPU context + // x3: ptr to debug reg struct // x4/x5/x6-22/x24-26: trashed mrs x26, id_aa64dfr0_el1 @@ -610,15 +611,15 @@ __save_debug: sub w25, w26, w25 // How many WPs to skip mov x5, x24 - add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + add x4, x3, #DEBUG_BCR save_debug dbgbcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + add x4, x3, #DEBUG_BVR save_debug dbgbvr mov x5, x25 - add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + add x4, x3, #DEBUG_WCR save_debug dbgwcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + add x4, x3, #DEBUG_WVR save_debug dbgwvr mrs x21, mdccint_el1 @@ -628,6 +629,7 @@ __save_debug: /* Restore debug state */ __restore_debug: // x2: ptr to CPU context + // x3: ptr to debug reg struct // x4/x5/x6-22/x24-26: trashed mrs x26, id_aa64dfr0_el1 @@ -638,15 +640,15 @@ __restore_debug: sub w25, w26, w25 // How many WPs to skip mov x5, x24 - add x4, x2, #CPU_SYSREG_OFFSET(DBGBCR0_EL1) + add x4, x3, #DEBUG_BCR restore_debug dbgbcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGBVR0_EL1) + add x4, x3, #DEBUG_BVR restore_debug dbgbvr mov x5, x25 - add x4, x2, #CPU_SYSREG_OFFSET(DBGWCR0_EL1) + add x4, x3, #DEBUG_WCR restore_debug dbgwcr - add x4, x2, #CPU_SYSREG_OFFSET(DBGWVR0_EL1) + add x4, x3, #DEBUG_WVR restore_debug dbgwvr ldr x21, [x2, #CPU_SYSREG_OFFSET(MDCCINT_EL1)] @@ -686,6 +688,7 @@ ENTRY(__kvm_vcpu_run) bl __save_sysregs compute_debug_state 1f + add x3, x0, #VCPU_HOST_DEBUG_STATE bl __save_debug 1: activate_traps @@ -701,6 +704,8 @@ ENTRY(__kvm_vcpu_run) bl __restore_fpsimd skip_debug_state x3, 1f + ldr x3, [x0, #VCPU_DEBUG_PTR] + kern_hyp_va x3 bl __restore_debug 1: restore_guest_32bit_state @@ -721,6 +726,8 @@ __kvm_vcpu_return: bl __save_sysregs skip_debug_state x3, 1f + ldr x3, [x0, #VCPU_DEBUG_PTR] + kern_hyp_va x3 bl __save_debug 1: save_guest_32bit_state @@ -743,6 +750,7 @@ __kvm_vcpu_return: // already been saved. Note that we nuke the whole 64bit word. // If we ever add more flags, we'll have to be more careful... str xzr, [x0, #VCPU_DEBUG_FLAGS] + add x3, x0, #VCPU_HOST_DEBUG_STATE bl __restore_debug 1: restore_host_regs diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index c370b40..158bae7 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -211,6 +211,203 @@ static bool trap_debug_regs(struct kvm_vcpu *vcpu, return true; } +/* + * reg_to_dbg/dbg_to_reg + * + * A 32 bit write to a debug register leave top bits alone + * A 32 bit read from a debug register only returns the bottom bits + * + * All writes will set the KVM_ARM64_DEBUG_DIRTY flag to ensure the + * hyp.S code switches between host and guest values in future. + */ +static inline void reg_to_dbg(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + u64 *dbg_reg) +{ + u64 val = *vcpu_reg(vcpu, p->Rt); + + if (p->is_32bit) { + val &= 0xffffffffUL; + val |= ((*dbg_reg >> 32) << 32); + } + + *dbg_reg = val; + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; +} + +static inline void dbg_to_reg(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + u64 *dbg_reg) +{ + u64 val = *dbg_reg; + + if (p->is_32bit) + val &= 0xffffffffUL; + + *vcpu_reg(vcpu, p->Rt) = val; +} + +static inline bool trap_bvr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static int get_bvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_bvr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg] = rd->val; +} + +static inline bool trap_bcr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + + return 0; +} + +static int get_bcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_bcr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_bcr[rd->reg] = rd->val; +} + +static inline bool trap_wvr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static int get_wvr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_wvr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_wvr[rd->reg] = rd->val; +} + +static inline bool trap_wcr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; + + if (p->is_write) + reg_to_dbg(vcpu, p, dbg_reg); + else + dbg_to_reg(vcpu, p, dbg_reg); + + return true; +} + +static int set_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; + + if (copy_from_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static int get_wcr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr) +{ + __u64 *r = &vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg]; + + if (copy_to_user(uaddr, r, KVM_REG_SIZE(reg->id)) != 0) + return -EFAULT; + return 0; +} + +static inline void reset_wcr(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + vcpu->arch.vcpu_debug_state.dbg_wcr[rd->reg] = rd->val; +} + static void reset_amair_el1(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) { u64 amair; @@ -240,16 +437,16 @@ static void reset_mpidr(struct kvm_vcpu *vcpu, const struct sys_reg_desc *r) #define DBG_BCR_BVR_WCR_WVR_EL1(n) \ /* DBGBVRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b100), \ - trap_debug_regs, reset_val, (DBGBVR0_EL1 + (n)), 0 }, \ + trap_bvr, reset_bvr, n, 0, get_bvr, set_bvr }, \ /* DBGBCRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b101), \ - trap_debug_regs, reset_val, (DBGBCR0_EL1 + (n)), 0 }, \ + trap_bcr, reset_bcr, n, 0, get_bcr, set_bcr }, \ /* DBGWVRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b110), \ - trap_debug_regs, reset_val, (DBGWVR0_EL1 + (n)), 0 }, \ + trap_wvr, reset_wvr, n, 0, get_wvr, set_wvr }, \ /* DBGWCRn_EL1 */ \ { Op0(0b10), Op1(0b000), CRn(0b0000), CRm((n)), Op2(0b111), \ - trap_debug_regs, reset_val, (DBGWCR0_EL1 + (n)), 0 } + trap_wcr, reset_wcr, n, 0, get_wcr, set_wcr } /* * Architected system registers. @@ -516,28 +713,55 @@ static bool trap_debug32(struct kvm_vcpu *vcpu, return true; } -#define DBG_BCR_BVR_WCR_WVR(n) \ - /* DBGBVRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_debug32, \ - NULL, (cp14_DBGBVR0 + (n) * 2) }, \ - /* DBGBCRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_debug32, \ - NULL, (cp14_DBGBCR0 + (n) * 2) }, \ - /* DBGWVRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_debug32, \ - NULL, (cp14_DBGWVR0 + (n) * 2) }, \ - /* DBGWCRn */ \ - { Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_debug32, \ - NULL, (cp14_DBGWCR0 + (n) * 2) } - -#define DBGBXVR(n) \ - { Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_debug32, \ - NULL, cp14_DBGBXVR0 + n * 2 } +/* AArch32 debug register mappings + * + * AArch32 DBGBVRn is mapped to DBGBVRn_EL1[31:0] + * AArch32 DBGBXVRn is mapped to DBGBVRn_EL1[63:32] + * + * All control registers and watchpoint value registers are mapped to + * the lower 32 bits of their AArch64 equivalents. We share the trap + * handlers with the above AArch64 code which checks what mode the + * system is in. + */ + +static inline bool trap_xvr(struct kvm_vcpu *vcpu, + const struct sys_reg_params *p, + const struct sys_reg_desc *rd) +{ + u64 *dbg_reg = &vcpu->arch.vcpu_debug_state.dbg_bvr[rd->reg]; + + if (p->is_write) { + u64 val = *dbg_reg; + + val &= 0xffffffffUL; + val |= *vcpu_reg(vcpu, p->Rt) << 32; + *dbg_reg = val; + + vcpu->arch.debug_flags |= KVM_ARM64_DEBUG_DIRTY; + } else { + *vcpu_reg(vcpu, p->Rt) = *dbg_reg >> 32; + } + + return true; +} + +#define DBG_BCR_BVR_WCR_WVR(n) \ + /* DBGBVRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 4), trap_bvr, NULL, n }, \ + /* DBGBCRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 5), trap_bcr, NULL, n }, \ + /* DBGWVRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 6), trap_wvr, NULL, n }, \ + /* DBGWCRn */ \ + { Op1( 0), CRn( 0), CRm((n)), Op2( 7), trap_wcr, NULL, n } + +#define DBGBXVR(n) \ + { Op1( 0), CRn( 1), CRm((n)), Op2( 1), trap_xvr, NULL, n } /* * Trapped cp14 registers. We generally ignore most of the external * debug, on the principle that they don't really make sense to a - * guest. Revisit this one day, whould this principle change. + * guest. Revisit this one day, would this principle change. */ static const struct sys_reg_desc cp14_regs[] = { /* DBGIDR */ @@ -1303,6 +1527,9 @@ int kvm_arm_sys_reg_get_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg if (!r) return get_invariant_sys_reg(reg->id, uaddr); + if (r->get_user) + return (r->get_user)(vcpu, r, reg, uaddr); + return reg_to_user(uaddr, &vcpu_sys_reg(vcpu, r->reg), reg->id); } @@ -1321,6 +1548,9 @@ int kvm_arm_sys_reg_set_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg if (!r) return set_invariant_sys_reg(reg->id, uaddr); + if (r->set_user) + return (r->set_user)(vcpu, r, reg, uaddr); + return reg_from_user(&vcpu_sys_reg(vcpu, r->reg), uaddr, reg->id); } diff --git a/arch/arm64/kvm/sys_regs.h b/arch/arm64/kvm/sys_regs.h index d411e25..eaa324e 100644 --- a/arch/arm64/kvm/sys_regs.h +++ b/arch/arm64/kvm/sys_regs.h @@ -55,6 +55,12 @@ struct sys_reg_desc { /* Value (usually reset value) */ u64 val; + + /* Custom get/set_user functions, fallback to generic if NULL */ + int (*get_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr); + int (*set_user)(struct kvm_vcpu *vcpu, const struct sys_reg_desc *rd, + const struct kvm_one_reg *reg, void __user *uaddr); }; static inline void print_sys_reg_instr(const struct sys_reg_params *p)
This introduces a level of indirection for the debug registers. Instead of using the sys_regs[] directly we store registers in a structure in the vcpu. The new kvm_arm_reset_debug_ptr() sets the debug ptr to the guest context. Because we no longer give the sys_regs offset for the sys_reg_desc->reg field, but instead the index into a debug-specific struct we need to add a number of additional trap functions for each register. Also as the generic generic user-space access code no longer works we have introduced a new pair of function pointers to the sys_reg_desc structure to override the generic code when needed. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> --- v6: - fix up some ws issues - correct clobber info - re-word commentary in kvm_host.h - fix endian access issues for aarch32 fields - revert all KVM_GET/SET_ONE_REG to 64bit (also see ABI update) v7 - new fn kvm_arm_reset_debug_ptr(), stubbed for arm - split trap fns into bcr,bvr,bcr,wvr and wxvr - add set/get fns to sys_regs_desc - reg_to_dbg/dbg_to_reg helpers for 32bit support v8 - rm #if 0 left over from re-factor - re-word reset_ptr comment - fix inadvertent whitespace changes - rename get/set to get_user/set_user - update commit wording - re-factor dbg_to_reg/reg_to_dbg - add newlines to keep checkpatch happy - ensure 63:32 of debug registers untouched by aarch32 --- arch/arm/include/asm/kvm_host.h | 1 + arch/arm/kvm/arm.c | 2 + arch/arm64/include/asm/kvm_asm.h | 24 ++-- arch/arm64/include/asm/kvm_host.h | 17 ++- arch/arm64/kernel/asm-offsets.c | 6 + arch/arm64/kvm/debug.c | 9 ++ arch/arm64/kvm/hyp.S | 24 ++-- arch/arm64/kvm/sys_regs.c | 274 +++++++++++++++++++++++++++++++++++--- arch/arm64/kvm/sys_regs.h | 6 + 9 files changed, 316 insertions(+), 47 deletions(-)