[PATCH v2] KVM: riscv: selftests: Add riscv vm satp modes
Andrew Jones
ajones at ventanamicro.com
Tue Nov 4 06:23:38 PST 2025
On Tue, Nov 04, 2025 at 08:53:27PM +0800, Wu Fei wrote:
> On 11/4/25 15:41, Anup Patel wrote:
> > On Wed, Oct 29, 2025 at 5:09 PM <wu.fei9 at sanechips.com.cn> wrote:
> > >
> > > Current vm modes cannot represent riscv guest modes precisely, here add
> > > all 9 combinations of P(56,40,41) x V(57,48,39). Also the default vm
> > > mode is detected on runtime instead of hardcoded one, which might not be
> > > supported on specific machine.
> > >
> > > Signed-off-by: Wu Fei <wu.fei9 at sanechips.com.cn>
> >
> > LGTM.
> >
> > Reviewed-by: Anup Patel <anup at brainfault.org>
> >
> > Please resend the patch CC'ing kvm at vger.kernel.org so that
> > folks working other architectures can also review.
>
> OK. As my company account is not working with git-send-email yet, is it a
> valid option to use my personal email to send the patch on behalf of company
> account?
Yes, what likely matters to your company is that your sign-off is with
your company email address, but there is no requirement for either the
address that sends the patch nor what address is used for the sign-off
on the community / mailing list side.
Thanks,
drew
>
> Thanks,
> Fei.
>
> >
> > Regards,
> > Anup
> >
> > > ---
> > > .../testing/selftests/kvm/include/kvm_util.h | 17 ++++-
> > > .../selftests/kvm/include/riscv/processor.h | 2 +
> > > tools/testing/selftests/kvm/lib/guest_modes.c | 41 +++++++++---
> > > tools/testing/selftests/kvm/lib/kvm_util.c | 33 ++++++++++
> > > .../selftests/kvm/lib/riscv/processor.c | 63 +++++++++++++++++--
> > > 5 files changed, 142 insertions(+), 14 deletions(-)
> > >
> > > diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
> > > index bee65ca08721..2055f0f5df82 100644
> > > --- a/tools/testing/selftests/kvm/include/kvm_util.h
> > > +++ b/tools/testing/selftests/kvm/include/kvm_util.h
> > > @@ -179,6 +179,17 @@ enum vm_guest_mode {
> > > VM_MODE_P36V48_64K,
> > > VM_MODE_P47V47_16K,
> > > VM_MODE_P36V47_16K,
> > > +
> > > + VM_MODE_P56V57_4K, /* For riscv64 */
> > > + VM_MODE_P56V48_4K,
> > > + VM_MODE_P56V39_4K,
> > > + VM_MODE_P50V57_4K,
> > > + VM_MODE_P50V48_4K,
> > > + VM_MODE_P50V39_4K,
> > > + VM_MODE_P41V57_4K,
> > > + VM_MODE_P41V48_4K,
> > > + VM_MODE_P41V39_4K,
> > > +
> > > NUM_VM_MODES,
> > > };
> > >
> > > @@ -203,10 +214,10 @@ kvm_static_assert(sizeof(struct vm_shape) == sizeof(uint64_t));
> > > shape; \
> > > })
> > >
> > > -#if defined(__aarch64__)
> > > -
> > > extern enum vm_guest_mode vm_mode_default;
> > >
> > > +#if defined(__aarch64__)
> > > +
> > > #define VM_MODE_DEFAULT vm_mode_default
> > > #define MIN_PAGE_SHIFT 12U
> > > #define ptes_per_page(page_size) ((page_size) / 8)
> > > @@ -229,7 +240,7 @@ extern enum vm_guest_mode vm_mode_default;
> > > #error "RISC-V 32-bit kvm selftests not supported"
> > > #endif
> > >
> > > -#define VM_MODE_DEFAULT VM_MODE_P40V48_4K
> > > +#define VM_MODE_DEFAULT vm_mode_default
> > > #define MIN_PAGE_SHIFT 12U
> > > #define ptes_per_page(page_size) ((page_size) / 8)
> > >
> > > diff --git a/tools/testing/selftests/kvm/include/riscv/processor.h b/tools/testing/selftests/kvm/include/riscv/processor.h
> > > index 162f303d9daa..2d5a5548e698 100644
> > > --- a/tools/testing/selftests/kvm/include/riscv/processor.h
> > > +++ b/tools/testing/selftests/kvm/include/riscv/processor.h
> > > @@ -191,4 +191,6 @@ static inline void local_irq_disable(void)
> > > csr_clear(CSR_SSTATUS, SR_SIE);
> > > }
> > >
> > > +unsigned long riscv64_get_satp_mode(void);
> > > +
> > > #endif /* SELFTEST_KVM_PROCESSOR_H */
> > > diff --git a/tools/testing/selftests/kvm/lib/guest_modes.c b/tools/testing/selftests/kvm/lib/guest_modes.c
> > > index b04901e55138..ce3099630397 100644
> > > --- a/tools/testing/selftests/kvm/lib/guest_modes.c
> > > +++ b/tools/testing/selftests/kvm/lib/guest_modes.c
> > > @@ -4,7 +4,7 @@
> > > */
> > > #include "guest_modes.h"
> > >
> > > -#ifdef __aarch64__
> > > +#if defined(__aarch64__) || defined(__riscv)
> > > #include "processor.h"
> > > enum vm_guest_mode vm_mode_default;
> > > #endif
> > > @@ -13,9 +13,11 @@ struct guest_mode guest_modes[NUM_VM_MODES];
> > >
> > > void guest_modes_append_default(void)
> > > {
> > > -#ifndef __aarch64__
> > > +#if !defined(__aarch64__) && !defined(__riscv)
> > > guest_mode_append(VM_MODE_DEFAULT, true);
> > > -#else
> > > +#endif
> > > +
> > > +#ifdef __aarch64__
> > > {
> > > unsigned int limit = kvm_check_cap(KVM_CAP_ARM_VM_IPA_SIZE);
> > > uint32_t ipa4k, ipa16k, ipa64k;
> > > @@ -74,11 +76,36 @@ void guest_modes_append_default(void)
> > > #ifdef __riscv
> > > {
> > > unsigned int sz = kvm_check_cap(KVM_CAP_VM_GPA_BITS);
> > > + unsigned long satp_mode = riscv64_get_satp_mode() << SATP_MODE_SHIFT;
> > > + int i;
> > >
> > > - if (sz >= 52)
> > > - guest_mode_append(VM_MODE_P52V48_4K, true);
> > > - if (sz >= 48)
> > > - guest_mode_append(VM_MODE_P48V48_4K, true);
> > > + switch (sz) {
> > > + case 59:
> > > + guest_mode_append(VM_MODE_P56V57_4K, satp_mode >= SATP_MODE_57);
> > > + guest_mode_append(VM_MODE_P56V48_4K, satp_mode >= SATP_MODE_48);
> > > + guest_mode_append(VM_MODE_P56V39_4K, satp_mode >= SATP_MODE_39);
> > > + break;
> > > + case 50:
> > > + guest_mode_append(VM_MODE_P50V57_4K, satp_mode >= SATP_MODE_57);
> > > + guest_mode_append(VM_MODE_P50V48_4K, satp_mode >= SATP_MODE_48);
> > > + guest_mode_append(VM_MODE_P50V39_4K, satp_mode >= SATP_MODE_39);
> > > + break;
> > > + case 41:
> > > + guest_mode_append(VM_MODE_P41V57_4K, satp_mode >= SATP_MODE_57);
> > > + guest_mode_append(VM_MODE_P41V48_4K, satp_mode >= SATP_MODE_48);
> > > + guest_mode_append(VM_MODE_P41V39_4K, satp_mode >= SATP_MODE_39);
> > > + break;
> > > + default:
> > > + break;
> > > + }
> > > +
> > > + /* set the first supported mode as default */
> > > + vm_mode_default = NUM_VM_MODES;
> > > + for (i = 0; vm_mode_default == NUM_VM_MODES && i < NUM_VM_MODES; i++) {
> > > + if (guest_modes[i].supported && guest_modes[i].enabled)
> > > + vm_mode_default = i;
> > > + }
> > > + TEST_ASSERT(vm_mode_default != NUM_VM_MODES, "No supported mode!");
> > > }
> > > #endif
> > > }
> > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> > > index a055343a7bf7..9803e61ae7db 100644
> > > --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> > > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> > > @@ -224,6 +224,15 @@ const char *vm_guest_mode_string(uint32_t i)
> > > [VM_MODE_P36V48_64K] = "PA-bits:36, VA-bits:48, 64K pages",
> > > [VM_MODE_P47V47_16K] = "PA-bits:47, VA-bits:47, 16K pages",
> > > [VM_MODE_P36V47_16K] = "PA-bits:36, VA-bits:47, 16K pages",
> > > + [VM_MODE_P56V57_4K] = "PA-bits:56, VA-bits:57, 4K pages",
> > > + [VM_MODE_P56V48_4K] = "PA-bits:56, VA-bits:48, 4K pages",
> > > + [VM_MODE_P56V39_4K] = "PA-bits:56, VA-bits:39, 4K pages",
> > > + [VM_MODE_P50V57_4K] = "PA-bits:50, VA-bits:57, 4K pages",
> > > + [VM_MODE_P50V48_4K] = "PA-bits:50, VA-bits:48, 4K pages",
> > > + [VM_MODE_P50V39_4K] = "PA-bits:50, VA-bits:39, 4K pages",
> > > + [VM_MODE_P41V57_4K] = "PA-bits:41, VA-bits:57, 4K pages",
> > > + [VM_MODE_P41V48_4K] = "PA-bits:41, VA-bits:48, 4K pages",
> > > + [VM_MODE_P41V39_4K] = "PA-bits:41, VA-bits:39, 4K pages",
> > > };
> > > _Static_assert(sizeof(strings)/sizeof(char *) == NUM_VM_MODES,
> > > "Missing new mode strings?");
> > > @@ -251,6 +260,15 @@ const struct vm_guest_mode_params vm_guest_mode_params[] = {
> > > [VM_MODE_P36V48_64K] = { 36, 48, 0x10000, 16 },
> > > [VM_MODE_P47V47_16K] = { 47, 47, 0x4000, 14 },
> > > [VM_MODE_P36V47_16K] = { 36, 47, 0x4000, 14 },
> > > + [VM_MODE_P56V57_4K] = { 56, 57, 0x1000, 12 },
> > > + [VM_MODE_P56V48_4K] = { 56, 48, 0x1000, 12 },
> > > + [VM_MODE_P56V39_4K] = { 56, 39, 0x1000, 12 },
> > > + [VM_MODE_P50V57_4K] = { 50, 57, 0x1000, 12 },
> > > + [VM_MODE_P50V48_4K] = { 50, 48, 0x1000, 12 },
> > > + [VM_MODE_P50V39_4K] = { 50, 39, 0x1000, 12 },
> > > + [VM_MODE_P41V57_4K] = { 41, 57, 0x1000, 12 },
> > > + [VM_MODE_P41V48_4K] = { 41, 48, 0x1000, 12 },
> > > + [VM_MODE_P41V39_4K] = { 41, 39, 0x1000, 12 },
> > > };
> > > _Static_assert(sizeof(vm_guest_mode_params)/sizeof(struct vm_guest_mode_params) == NUM_VM_MODES,
> > > "Missing new mode params?");
> > > @@ -351,6 +369,21 @@ struct kvm_vm *____vm_create(struct vm_shape shape)
> > > case VM_MODE_P44V64_4K:
> > > vm->pgtable_levels = 5;
> > > break;
> > > + case VM_MODE_P56V57_4K:
> > > + case VM_MODE_P50V57_4K:
> > > + case VM_MODE_P41V57_4K:
> > > + vm->pgtable_levels = 5;
> > > + break;
> > > + case VM_MODE_P56V48_4K:
> > > + case VM_MODE_P50V48_4K:
> > > + case VM_MODE_P41V48_4K:
> > > + vm->pgtable_levels = 4;
> > > + break;
> > > + case VM_MODE_P56V39_4K:
> > > + case VM_MODE_P50V39_4K:
> > > + case VM_MODE_P41V39_4K:
> > > + vm->pgtable_levels = 3;
> > > + break;
> > > default:
> > > TEST_FAIL("Unknown guest mode: 0x%x", vm->mode);
> > > }
> > > diff --git a/tools/testing/selftests/kvm/lib/riscv/processor.c b/tools/testing/selftests/kvm/lib/riscv/processor.c
> > > index 2eac7d4b59e9..53675292b8eb 100644
> > > --- a/tools/testing/selftests/kvm/lib/riscv/processor.c
> > > +++ b/tools/testing/selftests/kvm/lib/riscv/processor.c
> > > @@ -8,6 +8,7 @@
> > > #include <linux/compiler.h>
> > > #include <assert.h>
> > >
> > > +#include "guest_modes.h"
> > > #include "kvm_util.h"
> > > #include "processor.h"
> > > #include "ucall_common.h"
> > > @@ -197,22 +198,41 @@ void riscv_vcpu_mmu_setup(struct kvm_vcpu *vcpu)
> > > {
> > > struct kvm_vm *vm = vcpu->vm;
> > > unsigned long satp;
> > > + unsigned long satp_mode;
> > > + unsigned long max_satp_mode;
> > >
> > > /*
> > > * The RISC-V Sv48 MMU mode supports 56-bit physical address
> > > * for 48-bit virtual address with 4KB last level page size.
> > > */
> > > switch (vm->mode) {
> > > - case VM_MODE_P52V48_4K:
> > > - case VM_MODE_P48V48_4K:
> > > - case VM_MODE_P40V48_4K:
> > > + case VM_MODE_P56V57_4K:
> > > + case VM_MODE_P50V57_4K:
> > > + case VM_MODE_P41V57_4K:
> > > + satp_mode = SATP_MODE_57;
> > > + break;
> > > + case VM_MODE_P56V48_4K:
> > > + case VM_MODE_P50V48_4K:
> > > + case VM_MODE_P41V48_4K:
> > > + satp_mode = SATP_MODE_48;
> > > + break;
> > > + case VM_MODE_P56V39_4K:
> > > + case VM_MODE_P50V39_4K:
> > > + case VM_MODE_P41V39_4K:
> > > + satp_mode = SATP_MODE_39;
> > > break;
> > > default:
> > > TEST_FAIL("Unknown guest mode, mode: 0x%x", vm->mode);
> > > }
> > >
> > > + max_satp_mode = vcpu_get_reg(vcpu, RISCV_CONFIG_REG(satp_mode));
> > > +
> > > + if ((satp_mode >> SATP_MODE_SHIFT) > max_satp_mode)
> > > + TEST_FAIL("Unable to set satp mode 0x%lx, max mode 0x%lx\n",
> > > + satp_mode >> SATP_MODE_SHIFT, max_satp_mode);
> > > +
> > > satp = (vm->pgd >> PGTBL_PAGE_SIZE_SHIFT) & SATP_PPN;
> > > - satp |= SATP_MODE_48;
> > > + satp |= satp_mode;
> > >
> > > vcpu_set_reg(vcpu, RISCV_GENERAL_CSR_REG(satp), satp);
> > > }
> > > @@ -515,3 +535,38 @@ unsigned long get_host_sbi_spec_version(void)
> > >
> > > return ret.value;
> > > }
> > > +
> > > +void kvm_selftest_arch_init(void)
> > > +{
> > > + /*
> > > + * riscv64 doesn't have a true default mode, so start by detecting the
> > > + * supported vm mode.
> > > + */
> > > + guest_modes_append_default();
> > > +}
> > > +
> > > +unsigned long riscv64_get_satp_mode(void)
> > > +{
> > > + int kvm_fd, vm_fd, vcpu_fd, err;
> > > + uint64_t val;
> > > + struct kvm_one_reg reg = {
> > > + .id = RISCV_CONFIG_REG(satp_mode),
> > > + .addr = (uint64_t)&val,
> > > + };
> > > +
> > > + kvm_fd = open_kvm_dev_path_or_exit();
> > > + vm_fd = __kvm_ioctl(kvm_fd, KVM_CREATE_VM, NULL);
> > > + TEST_ASSERT(vm_fd >= 0, KVM_IOCTL_ERROR(KVM_CREATE_VM, vm_fd));
> > > +
> > > + vcpu_fd = ioctl(vm_fd, KVM_CREATE_VCPU, 0);
> > > + TEST_ASSERT(vcpu_fd >= 0, KVM_IOCTL_ERROR(KVM_CREATE_VCPU, vcpu_fd));
> > > +
> > > + err = ioctl(vcpu_fd, KVM_GET_ONE_REG, ®);
> > > + TEST_ASSERT(err == 0, KVM_IOCTL_ERROR(KVM_GET_ONE_REG, vcpu_fd));
> > > +
> > > + close(vcpu_fd);
> > > + close(vm_fd);
> > > + close(kvm_fd);
> > > +
> > > + return val;
> > > +}
> > > --
> > > 2.43.0
> > >
> > > --
> > > kvm-riscv mailing list
> > > kvm-riscv at lists.infradead.org
> > > http://lists.infradead.org/mailman/listinfo/kvm-riscv
> >
>
>
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