| Message ID | 7e9d2d5518375083f10c92a3d1acd98914f69fd8.1690364259.git.haibo1.xu@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | RISCV: Add kvm Sstc timer selftest | expand |
On Thu, Jul 27, 2023 at 03:20:06PM +0800, Haibo Xu wrote: > Add the infrastructure for exception handling in riscv selftests. > Currently, the guest_unexp_trap handler was used by default, which > aborts the test. Customized handlers can be enabled by calling > vm_install_exception_handler(vector) or vm_install_interrupt_handler(). > > The code is inspired from that of x86/arm64. > > Signed-off-by: Haibo Xu <haibo1.xu@intel.com> > --- > tools/testing/selftests/kvm/Makefile | 1 + > .../selftests/kvm/include/riscv/processor.h | 49 +++++++++ > .../selftests/kvm/lib/riscv/handlers.S | 101 ++++++++++++++++++ > .../selftests/kvm/lib/riscv/processor.c | 57 ++++++++++ > 4 files changed, 208 insertions(+) > create mode 100644 tools/testing/selftests/kvm/lib/riscv/handlers.S > > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile > index c692cc86e7da..70f3a5ba991e 100644 > --- a/tools/testing/selftests/kvm/Makefile > +++ b/tools/testing/selftests/kvm/Makefile > @@ -52,6 +52,7 @@ LIBKVM_s390x += lib/s390x/diag318_test_handler.c > LIBKVM_s390x += lib/s390x/processor.c > LIBKVM_s390x += lib/s390x/ucall.c > > +LIBKVM_riscv += lib/riscv/handlers.S > LIBKVM_riscv += lib/riscv/processor.c > LIBKVM_riscv += lib/riscv/ucall.c > > diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h > index d00d213c3805..9ea6e7bedc61 100644 > --- a/tools/testing/selftests/kvm/include/riscv/processor.h > +++ b/tools/testing/selftests/kvm/include/riscv/processor.h > @@ -9,6 +9,7 @@ > > #include "kvm_util.h" > #include <linux/stringify.h> > +#include <asm/csr.h> > > static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t idx, > uint64_t size) > @@ -38,6 +39,54 @@ static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t idx, > KVM_REG_RISCV_TIMER_REG(name), \ > KVM_REG_SIZE_U64) > > +struct ex_regs { > + unsigned long ra; > + unsigned long sp; > + unsigned long gp; > + unsigned long tp; > + unsigned long t0; > + unsigned long t1; > + unsigned long t2; > + unsigned long s0; > + unsigned long s1; > + unsigned long a0; > + unsigned long a1; > + unsigned long a2; > + unsigned long a3; > + unsigned long a4; > + unsigned long a5; > + unsigned long a6; > + unsigned long a7; > + unsigned long s2; > + unsigned long s3; > + unsigned long s4; > + unsigned long s5; > + unsigned long s6; > + unsigned long s7; > + unsigned long s8; > + unsigned long s9; > + unsigned long s10; > + unsigned long s11; > + unsigned long t3; > + unsigned long t4; > + unsigned long t5; > + unsigned long t6; > + unsigned long epc; > + unsigned long status; > + unsigned long cause; > +}; > + > +#define VECTOR_NUM 2 > +#define EC_NUM 32 > +#define EC_MASK (EC_NUM - 1) nit: My personal preference is to use something like NR_VECTORS and NR_EXCEPTIONS for these, since *_NUM type names are ambiguous with named indices. > + > +void vm_init_trap_vector_tables(struct kvm_vm *vm); > +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu); I think we should use a common name for these prototypes that the other architectures agree to and then put them in a common header. My vote for the naming is, void vm_init_vector_tables(struct kvm_vm *vm); void vcpu_init_vector_tables(struct kvm_vcpu *vcpu); > + > +typedef void(*handler_fn)(struct ex_regs *); > +void vm_install_exception_handler(struct kvm_vm *vm, int ec, handler_fn handler); I'd also put this typedef and prototype in a common header (with s/ec/vector/ to what you have here) > +void vm_install_interrupt_handler(struct kvm_vm *vm, handler_fn handler); I guess this one can stay risc-v specific for now since no other arch is using it. > + > /* L3 index Bit[47:39] */ > #define PGTBL_L3_INDEX_MASK 0x0000FF8000000000ULL > #define PGTBL_L3_INDEX_SHIFT 39 > diff --git a/tools/testing/selftests/kvm/lib/riscv/handlers.S b/tools/testing/selftests/kvm/lib/riscv/handlers.S > new file mode 100644 > index 000000000000..ce0b1d5415b9 > --- /dev/null > +++ b/tools/testing/selftests/kvm/lib/riscv/handlers.S > @@ -0,0 +1,101 @@ > +// SPDX-License-Identifier: GPL-2.0 */ > +/* > + * Copyright (c) 2023 Intel Corporation > + */ > + > +#include <asm/csr.h> General note for all the asm below, please format with the first operand aligned, so <tab>op<tab>operand1, operand2, ... > + > +.macro save_context > + addi sp, sp, (-8*34) > + > + sd x1, 0(sp) > + sd x2, 8(sp) > + sd x3, 16(sp) > + sd x4, 24(sp) > + sd x5, 32(sp) > + sd x6, 40(sp) > + sd x7, 48(sp) > + sd x8, 56(sp) > + sd x9, 64(sp) > + sd x10, 72(sp) > + sd x11, 80(sp) > + sd x12, 88(sp) > + sd x13, 96(sp) > + sd x14, 104(sp) > + sd x15, 112(sp) > + sd x16, 120(sp) > + sd x17, 128(sp) > + sd x18, 136(sp) > + sd x19, 144(sp) > + sd x20, 152(sp) > + sd x21, 160(sp) > + sd x22, 168(sp) > + sd x23, 176(sp) > + sd x24, 184(sp) > + sd x25, 192(sp) > + sd x26, 200(sp) > + sd x27, 208(sp) > + sd x28, 216(sp) > + sd x29, 224(sp) > + sd x30, 232(sp) > + sd x31, 240(sp) > + > + csrr s0, CSR_SEPC > + csrr s1, CSR_SSTATUS > + csrr s2, CSR_SCAUSE > + sd s0, 248(sp) > + sd s1, 256(sp) > + sd s2, 264(sp) > +.endm Let's create a restore_context macro too in order to maintain balance. > + > +.balign 4 > +.global exception_vectors > +exception_vectors: > + save_context > + move a0, sp > + la ra, ret_from_exception > + tail route_exception > + > +.global ret_from_exception > +ret_from_exception: > + ld s2, 264(sp) > + ld s1, 256(sp) > + ld s0, 248(sp) > + csrw CSR_SCAUSE, s2 > + csrw CSR_SSTATUS, s1 > + csrw CSR_SEPC, s0 > + > + ld x31, 240(sp) > + ld x30, 232(sp) > + ld x29, 224(sp) > + ld x28, 216(sp) > + ld x27, 208(sp) > + ld x26, 200(sp) > + ld x25, 192(sp) > + ld x24, 184(sp) > + ld x23, 176(sp) > + ld x22, 168(sp) > + ld x21, 160(sp) > + ld x20, 152(sp) > + ld x19, 144(sp) > + ld x18, 136(sp) > + ld x17, 128(sp) > + ld x16, 120(sp) > + ld x15, 112(sp) > + ld x14, 104(sp) > + ld x13, 96(sp) > + ld x12, 88(sp) > + ld x11, 80(sp) > + ld x10, 72(sp) > + ld x9, 64(sp) > + ld x8, 56(sp) > + ld x7, 48(sp) > + ld x6, 40(sp) > + ld x5, 32(sp) > + ld x4, 24(sp) > + ld x3, 16(sp) > + ld x2, 8(sp) > + ld x1, 0(sp) > + > + addi sp, sp, (8*34) > + sret > diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c > index d146ca71e0c0..f1b0be58a5dc 100644 > --- a/tools/testing/selftests/kvm/lib/riscv/processor.c > +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c > @@ -13,6 +13,8 @@ > > #define DEFAULT_RISCV_GUEST_STACK_VADDR_MIN 0xac0000 > > +static vm_vaddr_t exception_handlers; > + > static uint64_t page_align(struct kvm_vm *vm, uint64_t v) > { > return (v + vm->page_size) & ~(vm->page_size - 1); > @@ -367,3 +369,58 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...) > void assert_on_unhandled_exception(struct kvm_vcpu *vcpu) > { > } > + > +struct handlers { > + handler_fn exception_handlers[VECTOR_NUM][EC_NUM]; > +}; > + > +void route_exception(struct ex_regs *regs) > +{ > + struct handlers *handlers = (struct handlers *)exception_handlers; > + int vector = 0, ec; > + > + ec = regs->cause & ~CAUSE_IRQ_FLAG; > + if (ec >= EC_NUM) > + goto guest_unexpected_trap; > + > + /* Use the same handler for all the interrupts */ > + if (regs->cause & CAUSE_IRQ_FLAG) { > + vector = 1; > + ec = 0; > + } > + > + if (handlers && handlers->exception_handlers[vector][ec]) > + return handlers->exception_handlers[vector][ec](regs); > + > +guest_unexpected_trap: > + return guest_unexp_trap(); I think we want this to have consistent behavior with the other architectures, so we should be issuing a UCALL_UNHANDLED. > +} > + > +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu) > +{ > + extern char exception_vectors; > + > + vcpu_set_reg(vcpu, RISCV_CSR_REG(stvec), (unsigned long)&exception_vectors); > +} > + > +void vm_init_trap_vector_tables(struct kvm_vm *vm) > +{ > + vm->handlers = __vm_vaddr_alloc(vm, sizeof(struct handlers), > + vm->page_size, MEM_REGION_DATA); > + > + *(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers; > +} > + > +void vm_install_exception_handler(struct kvm_vm *vm, int ec, void (*handler)(struct ex_regs *)) > +{ > + struct handlers *handlers = addr_gva2hva(vm, vm->handlers); > + Add assert here that ec is valid. > + handlers->exception_handlers[0][ec] = handler; > +} > + > +void vm_install_interrupt_handler(struct kvm_vm *vm, void (*handler)(struct ex_regs *)) > +{ > + struct handlers *handlers = addr_gva2hva(vm, vm->handlers); > + > + handlers->exception_handlers[1][0] = handler; > +} > -- > 2.34.1 > Besides some nits and wanting to get more consistency with the other architectures, this looks good to me. Thanks, drew
On Fri, Jul 28, 2023, Andrew Jones wrote: > On Thu, Jul 27, 2023 at 03:20:06PM +0800, Haibo Xu wrote: > > +void vm_init_trap_vector_tables(struct kvm_vm *vm); > > +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu); > > I think we should use a common name for these prototypes that the other > architectures agree to and then put them in a common header. My vote for > the naming is, Just allocate the tables in kvm_arch_vm_post_create(). I've been meaning to convert x86 and ARM, but keep getting distracted/waylaid by other things. https://lore.kernel.org/all/Y8hCBOndYMD9zsDL@google.com > void vm_init_vector_tables(struct kvm_vm *vm); > void vcpu_init_vector_tables(struct kvm_vcpu *vcpu); > > > + > > +typedef void(*handler_fn)(struct ex_regs *); > > +void vm_install_exception_handler(struct kvm_vm *vm, int ec, handler_fn handler); > > I'd also put this typedef And rename it to (*exception_handler_fn). > and prototype in a common header (with s/ec/vector/ to what you have here) Hmm, yeah, I think it makes sense to let vm_install_exception_handler() be used from common code. the vector to be installed is inherently arch specific, but it would be easy enough for a test to use #ifdeffery to define the correct vector.
On Fri, Jul 28, 2023 at 5:37 PM Andrew Jones <ajones@ventanamicro.com> wrote: > > On Thu, Jul 27, 2023 at 03:20:06PM +0800, Haibo Xu wrote: > > Add the infrastructure for exception handling in riscv selftests. > > Currently, the guest_unexp_trap handler was used by default, which > > aborts the test. Customized handlers can be enabled by calling > > vm_install_exception_handler(vector) or vm_install_interrupt_handler(). > > > > The code is inspired from that of x86/arm64. > > > > Signed-off-by: Haibo Xu <haibo1.xu@intel.com> > > --- > > tools/testing/selftests/kvm/Makefile | 1 + > > .../selftests/kvm/include/riscv/processor.h | 49 +++++++++ > > .../selftests/kvm/lib/riscv/handlers.S | 101 ++++++++++++++++++ > > .../selftests/kvm/lib/riscv/processor.c | 57 ++++++++++ > > 4 files changed, 208 insertions(+) > > create mode 100644 tools/testing/selftests/kvm/lib/riscv/handlers.S > > > > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile > > index c692cc86e7da..70f3a5ba991e 100644 > > --- a/tools/testing/selftests/kvm/Makefile > > +++ b/tools/testing/selftests/kvm/Makefile > > @@ -52,6 +52,7 @@ LIBKVM_s390x += lib/s390x/diag318_test_handler.c > > LIBKVM_s390x += lib/s390x/processor.c > > LIBKVM_s390x += lib/s390x/ucall.c > > > > +LIBKVM_riscv += lib/riscv/handlers.S > > LIBKVM_riscv += lib/riscv/processor.c > > LIBKVM_riscv += lib/riscv/ucall.c > > > > diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h > > index d00d213c3805..9ea6e7bedc61 100644 > > --- a/tools/testing/selftests/kvm/include/riscv/processor.h > > +++ b/tools/testing/selftests/kvm/include/riscv/processor.h > > @@ -9,6 +9,7 @@ > > > > #include "kvm_util.h" > > #include <linux/stringify.h> > > +#include <asm/csr.h> > > > > static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t idx, > > uint64_t size) > > @@ -38,6 +39,54 @@ static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t idx, > > KVM_REG_RISCV_TIMER_REG(name), \ > > KVM_REG_SIZE_U64) > > > > +struct ex_regs { > > + unsigned long ra; > > + unsigned long sp; > > + unsigned long gp; > > + unsigned long tp; > > + unsigned long t0; > > + unsigned long t1; > > + unsigned long t2; > > + unsigned long s0; > > + unsigned long s1; > > + unsigned long a0; > > + unsigned long a1; > > + unsigned long a2; > > + unsigned long a3; > > + unsigned long a4; > > + unsigned long a5; > > + unsigned long a6; > > + unsigned long a7; > > + unsigned long s2; > > + unsigned long s3; > > + unsigned long s4; > > + unsigned long s5; > > + unsigned long s6; > > + unsigned long s7; > > + unsigned long s8; > > + unsigned long s9; > > + unsigned long s10; > > + unsigned long s11; > > + unsigned long t3; > > + unsigned long t4; > > + unsigned long t5; > > + unsigned long t6; > > + unsigned long epc; > > + unsigned long status; > > + unsigned long cause; > > +}; > > + > > +#define VECTOR_NUM 2 > > +#define EC_NUM 32 > > +#define EC_MASK (EC_NUM - 1) > > nit: My personal preference is to use something like NR_VECTORS and > NR_EXCEPTIONS for these, since *_NUM type names are ambiguous with > named indices. > > > + > > +void vm_init_trap_vector_tables(struct kvm_vm *vm); > > +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu); > > I think we should use a common name for these prototypes that the other > architectures agree to and then put them in a common header. My vote for > the naming is, > > void vm_init_vector_tables(struct kvm_vm *vm); > void vcpu_init_vector_tables(struct kvm_vcpu *vcpu); > > > + > > +typedef void(*handler_fn)(struct ex_regs *); > > +void vm_install_exception_handler(struct kvm_vm *vm, int ec, handler_fn handler); > > I'd also put this typedef and prototype in a common header > (with s/ec/vector/ to what you have here) > > > +void vm_install_interrupt_handler(struct kvm_vm *vm, handler_fn handler); > > I guess this one can stay risc-v specific for now since no other arch is > using it. > > > + > > /* L3 index Bit[47:39] */ > > #define PGTBL_L3_INDEX_MASK 0x0000FF8000000000ULL > > #define PGTBL_L3_INDEX_SHIFT 39 > > diff --git a/tools/testing/selftests/kvm/lib/riscv/handlers.S b/tools/testing/selftests/kvm/lib/riscv/handlers.S > > new file mode 100644 > > index 000000000000..ce0b1d5415b9 > > --- /dev/null > > +++ b/tools/testing/selftests/kvm/lib/riscv/handlers.S > > @@ -0,0 +1,101 @@ > > +// SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * Copyright (c) 2023 Intel Corporation > > + */ > > + > > +#include <asm/csr.h> > > General note for all the asm below, please format with the first operand > aligned, so > > <tab>op<tab>operand1, operand2, ... > > > + > > +.macro save_context > > + addi sp, sp, (-8*34) > > + > > + sd x1, 0(sp) > > + sd x2, 8(sp) > > + sd x3, 16(sp) > > + sd x4, 24(sp) > > + sd x5, 32(sp) > > + sd x6, 40(sp) > > + sd x7, 48(sp) > > + sd x8, 56(sp) > > + sd x9, 64(sp) > > + sd x10, 72(sp) > > + sd x11, 80(sp) > > + sd x12, 88(sp) > > + sd x13, 96(sp) > > + sd x14, 104(sp) > > + sd x15, 112(sp) > > + sd x16, 120(sp) > > + sd x17, 128(sp) > > + sd x18, 136(sp) > > + sd x19, 144(sp) > > + sd x20, 152(sp) > > + sd x21, 160(sp) > > + sd x22, 168(sp) > > + sd x23, 176(sp) > > + sd x24, 184(sp) > > + sd x25, 192(sp) > > + sd x26, 200(sp) > > + sd x27, 208(sp) > > + sd x28, 216(sp) > > + sd x29, 224(sp) > > + sd x30, 232(sp) > > + sd x31, 240(sp) > > + > > + csrr s0, CSR_SEPC > > + csrr s1, CSR_SSTATUS > > + csrr s2, CSR_SCAUSE > > + sd s0, 248(sp) > > + sd s1, 256(sp) > > + sd s2, 264(sp) > > +.endm > > Let's create a restore_context macro too in order to maintain balance. > > > + > > +.balign 4 > > +.global exception_vectors > > +exception_vectors: > > + save_context > > + move a0, sp > > + la ra, ret_from_exception > > + tail route_exception > > + > > +.global ret_from_exception > > +ret_from_exception: > > + ld s2, 264(sp) > > + ld s1, 256(sp) > > + ld s0, 248(sp) > > + csrw CSR_SCAUSE, s2 > > + csrw CSR_SSTATUS, s1 > > + csrw CSR_SEPC, s0 > > + > > + ld x31, 240(sp) > > + ld x30, 232(sp) > > + ld x29, 224(sp) > > + ld x28, 216(sp) > > + ld x27, 208(sp) > > + ld x26, 200(sp) > > + ld x25, 192(sp) > > + ld x24, 184(sp) > > + ld x23, 176(sp) > > + ld x22, 168(sp) > > + ld x21, 160(sp) > > + ld x20, 152(sp) > > + ld x19, 144(sp) > > + ld x18, 136(sp) > > + ld x17, 128(sp) > > + ld x16, 120(sp) > > + ld x15, 112(sp) > > + ld x14, 104(sp) > > + ld x13, 96(sp) > > + ld x12, 88(sp) > > + ld x11, 80(sp) > > + ld x10, 72(sp) > > + ld x9, 64(sp) > > + ld x8, 56(sp) > > + ld x7, 48(sp) > > + ld x6, 40(sp) > > + ld x5, 32(sp) > > + ld x4, 24(sp) > > + ld x3, 16(sp) > > + ld x2, 8(sp) > > + ld x1, 0(sp) > > + > > + addi sp, sp, (8*34) > > + sret > > diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c > > index d146ca71e0c0..f1b0be58a5dc 100644 > > --- a/tools/testing/selftests/kvm/lib/riscv/processor.c > > +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c > > @@ -13,6 +13,8 @@ > > > > #define DEFAULT_RISCV_GUEST_STACK_VADDR_MIN 0xac0000 > > > > +static vm_vaddr_t exception_handlers; > > + > > static uint64_t page_align(struct kvm_vm *vm, uint64_t v) > > { > > return (v + vm->page_size) & ~(vm->page_size - 1); > > @@ -367,3 +369,58 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...) > > void assert_on_unhandled_exception(struct kvm_vcpu *vcpu) > > { > > } > > + > > +struct handlers { > > + handler_fn exception_handlers[VECTOR_NUM][EC_NUM]; > > +}; > > + > > +void route_exception(struct ex_regs *regs) > > +{ > > + struct handlers *handlers = (struct handlers *)exception_handlers; > > + int vector = 0, ec; > > + > > + ec = regs->cause & ~CAUSE_IRQ_FLAG; > > + if (ec >= EC_NUM) > > + goto guest_unexpected_trap; > > + > > + /* Use the same handler for all the interrupts */ > > + if (regs->cause & CAUSE_IRQ_FLAG) { > > + vector = 1; > > + ec = 0; > > + } > > + > > + if (handlers && handlers->exception_handlers[vector][ec]) > > + return handlers->exception_handlers[vector][ec](regs); > > + > > +guest_unexpected_trap: > > + return guest_unexp_trap(); > > I think we want this to have consistent behavior with the other > architectures, so we should be issuing a UCALL_UNHANDLED. > > > +} > > + > > +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu) > > +{ > > + extern char exception_vectors; > > + > > + vcpu_set_reg(vcpu, RISCV_CSR_REG(stvec), (unsigned long)&exception_vectors); > > +} > > + > > +void vm_init_trap_vector_tables(struct kvm_vm *vm) > > +{ > > + vm->handlers = __vm_vaddr_alloc(vm, sizeof(struct handlers), > > + vm->page_size, MEM_REGION_DATA); > > + > > + *(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers; > > +} > > + > > +void vm_install_exception_handler(struct kvm_vm *vm, int ec, void (*handler)(struct ex_regs *)) > > +{ > > + struct handlers *handlers = addr_gva2hva(vm, vm->handlers); > > + > > Add assert here that ec is valid. > > > + handlers->exception_handlers[0][ec] = handler; > > +} > > + > > +void vm_install_interrupt_handler(struct kvm_vm *vm, void (*handler)(struct ex_regs *)) > > +{ > > + struct handlers *handlers = addr_gva2hva(vm, vm->handlers); > > + > > + handlers->exception_handlers[1][0] = handler; > > +} > > -- > > 2.34.1 > > > > Besides some nits and wanting to get more consistency with the other > architectures, this looks good to me. > Thanks for the review! Will fix them in v2. > Thanks, > drew
On Fri, Jul 28, 2023 at 11:53 PM Sean Christopherson <seanjc@google.com> wrote: > > On Fri, Jul 28, 2023, Andrew Jones wrote: > > On Thu, Jul 27, 2023 at 03:20:06PM +0800, Haibo Xu wrote: > > > +void vm_init_trap_vector_tables(struct kvm_vm *vm); > > > +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu); > > > > I think we should use a common name for these prototypes that the other > > architectures agree to and then put them in a common header. My vote for > > the naming is, > > Just allocate the tables in kvm_arch_vm_post_create(). I've been meaning to > convert x86 and ARM, but keep getting distracted/waylaid by other things. > > https://lore.kernel.org/all/Y8hCBOndYMD9zsDL@google.com > > > void vm_init_vector_tables(struct kvm_vm *vm); > > void vcpu_init_vector_tables(struct kvm_vcpu *vcpu); > > > > > + > > > +typedef void(*handler_fn)(struct ex_regs *); > > > +void vm_install_exception_handler(struct kvm_vm *vm, int ec, handler_fn handler); > > > > I'd also put this typedef > > And rename it to (*exception_handler_fn). > > > and prototype in a common header (with s/ec/vector/ to what you have here) > > Hmm, yeah, I think it makes sense to let vm_install_exception_handler() be used > from common code. the vector to be installed is inherently arch specific, but > it would be easy enough for a test to use #ifdeffery to define the correct vector. Thanks for the suggestion. I'll have a try to consolidate these codes in v2.
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile index c692cc86e7da..70f3a5ba991e 100644 --- a/tools/testing/selftests/kvm/Makefile +++ b/tools/testing/selftests/kvm/Makefile @@ -52,6 +52,7 @@ LIBKVM_s390x += lib/s390x/diag318_test_handler.c LIBKVM_s390x += lib/s390x/processor.c LIBKVM_s390x += lib/s390x/ucall.c +LIBKVM_riscv += lib/riscv/handlers.S LIBKVM_riscv += lib/riscv/processor.c LIBKVM_riscv += lib/riscv/ucall.c diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h index d00d213c3805..9ea6e7bedc61 100644 --- a/tools/testing/selftests/kvm/include/riscv/processor.h +++ b/tools/testing/selftests/kvm/include/riscv/processor.h @@ -9,6 +9,7 @@ #include "kvm_util.h" #include <linux/stringify.h> +#include <asm/csr.h> static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t idx, uint64_t size) @@ -38,6 +39,54 @@ static inline uint64_t __kvm_reg_id(uint64_t type, uint64_t idx, KVM_REG_RISCV_TIMER_REG(name), \ KVM_REG_SIZE_U64) +struct ex_regs { + unsigned long ra; + unsigned long sp; + unsigned long gp; + unsigned long tp; + unsigned long t0; + unsigned long t1; + unsigned long t2; + unsigned long s0; + unsigned long s1; + unsigned long a0; + unsigned long a1; + unsigned long a2; + unsigned long a3; + unsigned long a4; + unsigned long a5; + unsigned long a6; + unsigned long a7; + unsigned long s2; + unsigned long s3; + unsigned long s4; + unsigned long s5; + unsigned long s6; + unsigned long s7; + unsigned long s8; + unsigned long s9; + unsigned long s10; + unsigned long s11; + unsigned long t3; + unsigned long t4; + unsigned long t5; + unsigned long t6; + unsigned long epc; + unsigned long status; + unsigned long cause; +}; + +#define VECTOR_NUM 2 +#define EC_NUM 32 +#define EC_MASK (EC_NUM - 1) + +void vm_init_trap_vector_tables(struct kvm_vm *vm); +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu); + +typedef void(*handler_fn)(struct ex_regs *); +void vm_install_exception_handler(struct kvm_vm *vm, int ec, handler_fn handler); +void vm_install_interrupt_handler(struct kvm_vm *vm, handler_fn handler); + /* L3 index Bit[47:39] */ #define PGTBL_L3_INDEX_MASK 0x0000FF8000000000ULL #define PGTBL_L3_INDEX_SHIFT 39 diff --git a/tools/testing/selftests/kvm/lib/riscv/handlers.S b/tools/testing/selftests/kvm/lib/riscv/handlers.S new file mode 100644 index 000000000000..ce0b1d5415b9 --- /dev/null +++ b/tools/testing/selftests/kvm/lib/riscv/handlers.S @@ -0,0 +1,101 @@ +// SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2023 Intel Corporation + */ + +#include <asm/csr.h> + +.macro save_context + addi sp, sp, (-8*34) + + sd x1, 0(sp) + sd x2, 8(sp) + sd x3, 16(sp) + sd x4, 24(sp) + sd x5, 32(sp) + sd x6, 40(sp) + sd x7, 48(sp) + sd x8, 56(sp) + sd x9, 64(sp) + sd x10, 72(sp) + sd x11, 80(sp) + sd x12, 88(sp) + sd x13, 96(sp) + sd x14, 104(sp) + sd x15, 112(sp) + sd x16, 120(sp) + sd x17, 128(sp) + sd x18, 136(sp) + sd x19, 144(sp) + sd x20, 152(sp) + sd x21, 160(sp) + sd x22, 168(sp) + sd x23, 176(sp) + sd x24, 184(sp) + sd x25, 192(sp) + sd x26, 200(sp) + sd x27, 208(sp) + sd x28, 216(sp) + sd x29, 224(sp) + sd x30, 232(sp) + sd x31, 240(sp) + + csrr s0, CSR_SEPC + csrr s1, CSR_SSTATUS + csrr s2, CSR_SCAUSE + sd s0, 248(sp) + sd s1, 256(sp) + sd s2, 264(sp) +.endm + +.balign 4 +.global exception_vectors +exception_vectors: + save_context + move a0, sp + la ra, ret_from_exception + tail route_exception + +.global ret_from_exception +ret_from_exception: + ld s2, 264(sp) + ld s1, 256(sp) + ld s0, 248(sp) + csrw CSR_SCAUSE, s2 + csrw CSR_SSTATUS, s1 + csrw CSR_SEPC, s0 + + ld x31, 240(sp) + ld x30, 232(sp) + ld x29, 224(sp) + ld x28, 216(sp) + ld x27, 208(sp) + ld x26, 200(sp) + ld x25, 192(sp) + ld x24, 184(sp) + ld x23, 176(sp) + ld x22, 168(sp) + ld x21, 160(sp) + ld x20, 152(sp) + ld x19, 144(sp) + ld x18, 136(sp) + ld x17, 128(sp) + ld x16, 120(sp) + ld x15, 112(sp) + ld x14, 104(sp) + ld x13, 96(sp) + ld x12, 88(sp) + ld x11, 80(sp) + ld x10, 72(sp) + ld x9, 64(sp) + ld x8, 56(sp) + ld x7, 48(sp) + ld x6, 40(sp) + ld x5, 32(sp) + ld x4, 24(sp) + ld x3, 16(sp) + ld x2, 8(sp) + ld x1, 0(sp) + + addi sp, sp, (8*34) + sret diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c index d146ca71e0c0..f1b0be58a5dc 100644 --- a/tools/testing/selftests/kvm/lib/riscv/processor.c +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c @@ -13,6 +13,8 @@ #define DEFAULT_RISCV_GUEST_STACK_VADDR_MIN 0xac0000 +static vm_vaddr_t exception_handlers; + static uint64_t page_align(struct kvm_vm *vm, uint64_t v) { return (v + vm->page_size) & ~(vm->page_size - 1); @@ -367,3 +369,58 @@ void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...) void assert_on_unhandled_exception(struct kvm_vcpu *vcpu) { } + +struct handlers { + handler_fn exception_handlers[VECTOR_NUM][EC_NUM]; +}; + +void route_exception(struct ex_regs *regs) +{ + struct handlers *handlers = (struct handlers *)exception_handlers; + int vector = 0, ec; + + ec = regs->cause & ~CAUSE_IRQ_FLAG; + if (ec >= EC_NUM) + goto guest_unexpected_trap; + + /* Use the same handler for all the interrupts */ + if (regs->cause & CAUSE_IRQ_FLAG) { + vector = 1; + ec = 0; + } + + if (handlers && handlers->exception_handlers[vector][ec]) + return handlers->exception_handlers[vector][ec](regs); + +guest_unexpected_trap: + return guest_unexp_trap(); +} + +void vcpu_init_trap_vector_tables(struct kvm_vcpu *vcpu) +{ + extern char exception_vectors; + + vcpu_set_reg(vcpu, RISCV_CSR_REG(stvec), (unsigned long)&exception_vectors); +} + +void vm_init_trap_vector_tables(struct kvm_vm *vm) +{ + vm->handlers = __vm_vaddr_alloc(vm, sizeof(struct handlers), + vm->page_size, MEM_REGION_DATA); + + *(vm_vaddr_t *)addr_gva2hva(vm, (vm_vaddr_t)(&exception_handlers)) = vm->handlers; +} + +void vm_install_exception_handler(struct kvm_vm *vm, int ec, void (*handler)(struct ex_regs *)) +{ + struct handlers *handlers = addr_gva2hva(vm, vm->handlers); + + handlers->exception_handlers[0][ec] = handler; +} + +void vm_install_interrupt_handler(struct kvm_vm *vm, void (*handler)(struct ex_regs *)) +{ + struct handlers *handlers = addr_gva2hva(vm, vm->handlers); + + handlers->exception_handlers[1][0] = handler; +}
Add the infrastructure for exception handling in riscv selftests. Currently, the guest_unexp_trap handler was used by default, which aborts the test. Customized handlers can be enabled by calling vm_install_exception_handler(vector) or vm_install_interrupt_handler(). The code is inspired from that of x86/arm64. Signed-off-by: Haibo Xu <haibo1.xu@intel.com> --- tools/testing/selftests/kvm/Makefile | 1 + .../selftests/kvm/include/riscv/processor.h | 49 +++++++++ .../selftests/kvm/lib/riscv/handlers.S | 101 ++++++++++++++++++ .../selftests/kvm/lib/riscv/processor.c | 57 ++++++++++ 4 files changed, 208 insertions(+) create mode 100644 tools/testing/selftests/kvm/lib/riscv/handlers.S