[PATCH v2 0/4] KVM: selftests: Add LoongArch support

[PATCH v2 0/4] KVM: selftests: Add LoongArch support

[Tianrui Zhao]

This patch series base on the Linux LoongArch KVM patch:
Based-on: <20230803022138.2736430-1-zhaotianrui@loongson.cn>

We add LoongArch support into KVM selftests and there are some KVM
test cases we have passed:
  kvm_create_max_vcpus
  demand_paging_test
  kvm_page_table_test
  set_memory_region_test
  memslot_modification_stress_test
  memslot_perf_test
  kvm_binary_stats_test

The test results:
1..7
selftests: kvm: kvm_create_max_vcpus
  KVM_CAP_MAX_VCPU_ID: 256
  KVM_CAP_MAX_VCPUS: 256
  Testing creating 256 vCPUs, with IDs 0...255.
  ok 1 selftests: kvm: kvm_create_max_vcpus

selftests: kvm: demand_paging_test
  Testing guest mode: PA-bits:36,  VA-bits:47, 16K pages
  guest physical test memory: [0xfbfffc000, 0xfffffc000)
  Finished creating vCPUs and starting uffd threads
  Started all vCPUs
  All vCPU threads joined
  Total guest execution time: 0.787727423s
  Overall demand paging rate: 83196.291111 pgs/sec
  ok 2 selftests: kvm: demand_paging_test

selftests: kvm: kvm_page_table_test
  Testing guest mode: PA-bits:36,  VA-bits:47, 16K pages
  Testing memory backing src type: anonymous
  Testing memory backing src granularity: 0x4000
  Testing memory size(aligned): 0x40000000
  Guest physical test memory offset: 0xfbfffc000
  Host  virtual  test memory offset: 0xffb011c000
  Number of testing vCPUs: 1
  Started all vCPUs successfully
  KVM_CREATE_MAPPINGS: total execution time: -3.-672213074s
  KVM_UPDATE_MAPPINGS: total execution time: -4.-381650744s
  KVM_ADJUST_MAPPINGS: total execution time: -4.-434860241s
  ok 3 selftests: kvm: kvm_page_table_test

selftests: kvm: set_memory_region_test
  Allowed number of memory slots: 256
  Adding slots 0..255, each memory region with 2048K size
  ok 4 selftests: kvm: set_memory_region_test

selftests: kvm: memslot_modification_stress_test
  Testing guest mode: PA-bits:36,  VA-bits:47, 16K pages
  guest physical test memory: [0xfbfffc000, 0xfffffc000)
  Finished creating vCPUs
  Started all vCPUs
  All vCPU threads joined
  ok 5 selftests: kvm: memslot_modification_stress_test

selftests: kvm: memslot_perf_test
  Testing map performance with 1 runs, 5 seconds each
  Test took 0.003797735s for slot setup + 5.012294023s all iterations
  Done 369 iterations, avg 0.013583452s each
  Best runtime result was 0.013583452s per iteration (with 369 iterations)

  Testing unmap performance with 1 runs, 5 seconds each
  Test took 0.003841196s for slot setup + 5.001802893s all iterations
  Done 341 iterations, avg 0.014668043s each
  Best runtime result was 0.014668043s per iteration (with 341 iterations)

  Testing unmap chunked performance with 1 runs, 5 seconds each
  Test took 0.003784356s for slot setup + 5.000265398s all iterations
  Done 7376 iterations, avg 0.000677910s each
  Best runtime result was 0.000677910s per iteration (with 7376 iterations)

  Testing move active area performance with 1 runs, 5 seconds each
  Test took 0.003828075s for slot setup + 5.000021760s all iterations
  Done 85449 iterations, avg 0.000058514s each
  Best runtime result was 0.000058514s per iteration (with 85449 iterations)

  Testing move inactive area performance with 1 runs, 5 seconds each
  Test took 0.003809146s for slot setup + 5.000024149s all iterations
  Done 181908 iterations, avg 0.000027486s each
  Best runtime result was 0.000027486s per iteration (with 181908 iterations)

  Testing RW performance with 1 runs, 5 seconds each
  Test took 0.003780596s for slot setup + 5.001116175s all iterations
  Done 391 iterations, avg 0.012790578s each
  Best runtime result was 0.012790578s per iteration (with 391 iterations)
  Best slot setup time for the whole test area was 0.003780596s
  ok 6 selftests: kvm: memslot_perf_test

selftests: kvm: kvm_binary_stats_test
  TAP version 13
  1..4
  ok 1 vm0
  ok 2 vm1
  ok 3 vm2
  ok 4 vm3
  Totals: pass:4 fail:0 xfail:0 xpass:0 skip:0 error:0
  ok 7 selftests: kvm: kvm_binary_stats_test

Changes for v2:
1. We should use ".balign 4096" to align the assemble code with 4K in
exception.S instead of "align 12".
2. LoongArch only supports 3 or 4 levels page tables, so we remove the
hanlders for 2-levels page table.
3. Remove the DEFAULT_LOONGARCH_GUEST_STACK_VADDR_MIN and use the common
DEFAULT_GUEST_STACK_VADDR_MIN to allocate stack memory in guest.
4. Reorganize the test cases supported by LoongArch.
5. Fix some code comments.
6. Add kvm_binary_stats_test test case into LoongArch KVM selftests.

changes for v1:
1. Add kvm selftests header files for LoongArch.
2. Add processor tests for LoongArch KVM.
3. Add ucall tests for LoongArch KVM.
4. Add LoongArch tests into makefile.

Tianrui Zhao (4):
  KVM: selftests: Add KVM selftests header files for LoongArch
  KVM: selftests: Add core KVM selftests support for LoongArch
  KVM: selftests: Add ucall test support for LoongArch
  KVM: selftests: Add test cases supported by LoongArch into makefile

 tools/testing/selftests/kvm/Makefile          |  12 +
 .../selftests/kvm/include/kvm_util_base.h     |   5 +
 .../kvm/include/loongarch/processor.h         | 107 ++++++
 .../selftests/kvm/lib/loongarch/exception.S   |  27 ++
 .../selftests/kvm/lib/loongarch/processor.c   | 356 ++++++++++++++++++
 .../selftests/kvm/lib/loongarch/ucall.c       |  43 +++
 6 files changed, 550 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/include/loongarch/processor.h
 create mode 100644 tools/testing/selftests/kvm/lib/loongarch/exception.S
 create mode 100644 tools/testing/selftests/kvm/lib/loongarch/processor.c
 create mode 100644 tools/testing/selftests/kvm/lib/loongarch/ucall.c

-- 
2.39.1

[PATCH v2 1/4] KVM: selftests: Add KVM selftests header files for LoongArch

[Tianrui Zhao]

Add KVM selftests header files for LoongArch, including processor.h
and kvm_util_base.h. Those mainly contain LoongArch CSR register defines
and page table information.

Based-on: <20230803022138.2736430-1-zhaotianrui@loongson.cn>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 .../selftests/kvm/include/kvm_util_base.h     |   5 +
 .../kvm/include/loongarch/processor.h         | 107 ++++++++++++++++++
 2 files changed, 112 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/include/loongarch/processor.h

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index eb1ff597bcca..adb20ab0345f 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -197,6 +197,11 @@ extern enum vm_guest_mode vm_mode_default;
 #define MIN_PAGE_SHIFT			12U
 #define ptes_per_page(page_size)	((page_size) / 8)
 
+#elif defined(__loongarch__)
+#define VM_MODE_DEFAULT			VM_MODE_P36V47_16K
+#define MIN_PAGE_SHIFT			14U
+#define ptes_per_page(page_size)	((page_size) / 8)
+
 #endif
 
 #define MIN_PAGE_SIZE		(1U << MIN_PAGE_SHIFT)
diff --git a/tools/testing/selftests/kvm/include/loongarch/processor.h b/tools/testing/selftests/kvm/include/loongarch/processor.h
new file mode 100644
index 000000000000..9486130325a9
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/loongarch/processor.h
@@ -0,0 +1,107 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef SELFTEST_KVM_PROCESSOR_H
+#define SELFTEST_KVM_PROCESSOR_H
+
+#define _PAGE_VALID_SHIFT	0
+#define _PAGE_DIRTY_SHIFT	1
+#define _PAGE_PLV_SHIFT		2  /* 2~3, two bits */
+#define _CACHE_SHIFT		4  /* 4~5, two bits */
+#define _PAGE_PRESENT_SHIFT	7
+#define _PAGE_WRITE_SHIFT	8
+
+#define PLV_KERN		0
+#define PLV_USER		3
+#define PLV_MASK		0x3
+
+#define _PAGE_VALID		(0x1UL << _PAGE_VALID_SHIFT)
+#define _PAGE_PRESENT		(0x1UL << _PAGE_PRESENT_SHIFT)
+#define _PAGE_WRITE		(0x1UL << _PAGE_WRITE_SHIFT)
+#define _PAGE_DIRTY		(0x1UL << _PAGE_DIRTY_SHIFT)
+#define _PAGE_USER		(PLV_USER << _PAGE_PLV_SHIFT)
+#define __READABLE		(_PAGE_VALID)
+#define __WRITEABLE		(_PAGE_DIRTY | _PAGE_WRITE)
+#define _CACHE_CC		(0x1UL << _CACHE_SHIFT) /* Coherent Cached */
+
+/* general registers */
+#define zero	$r0
+#define ra	$r1
+#define tp	$r2
+#define sp	$r3
+#define a0	$r4
+#define a1	$r5
+#define a2	$r6
+#define a3	$r7
+#define a4	$r8
+#define a5	$r9
+#define a6	$r10
+#define a7	$r11
+#define t0	$r12
+#define t1	$r13
+#define t2	$r14
+#define t3	$r15
+#define t4	$r16
+#define t5	$r17
+#define t6	$r18
+#define t7	$r19
+#define t8	$r20
+#define u0	$r21
+#define fp	$r22
+#define s0	$r23
+#define s1	$r24
+#define s2	$r25
+#define s3	$r26
+#define s4	$r27
+#define s5	$r28
+#define s6	$r29
+#define s7	$r30
+#define s8	$r31
+
+#define PS_4K				0x0000000c
+#define PS_8K				0x0000000d
+#define PS_16K				0x0000000e
+#define PS_DEFAULT_SIZE			PS_16K
+
+/* Basic CSR registers */
+#define LOONGARCH_CSR_CRMD		0x0 /* Current mode info */
+#define CSR_CRMD_PG_SHIFT		4
+#define CSR_CRMD_PG			(0x1UL << CSR_CRMD_PG_SHIFT)
+#define CSR_CRMD_IE_SHIFT		2
+#define CSR_CRMD_IE			(0x1UL << CSR_CRMD_IE_SHIFT)
+#define CSR_CRMD_PLV_SHIFT		0
+#define CSR_CRMD_PLV_WIDTH		2
+#define CSR_CRMD_PLV			(0x3UL << CSR_CRMD_PLV_SHIFT)
+#define PLV_MASK			0x3
+
+#define LOONGARCH_CSR_PRMD		0x1
+#define LOONGARCH_CSR_EUEN		0x2
+#define LOONGARCH_CSR_ECFG		0x4
+#define LOONGARCH_CSR_EENTRY		0xc
+#define LOONGARCH_CSR_TLBIDX		0x10 /* TLB Index, EHINV, PageSize, NP */
+#define CSR_TLBIDX_PS_SHIFT		24
+#define CSR_TLBIDX_PS_WIDTH		6
+#define CSR_TLBIDX_PS			(0x3fUL << CSR_TLBIDX_PS_SHIFT)
+#define CSR_TLBIDX_SIZEM		0x3f000000
+#define CSR_TLBIDX_SIZE			CSR_TLBIDX_PS_SHIFT
+
+#define LOONGARCH_CSR_ASID		0x18 /* ASID */
+/* Page table base address when VA[VALEN-1] = 0 */
+#define LOONGARCH_CSR_PGDL		0x19
+/* Page table base address when VA[VALEN-1] = 1 */
+#define LOONGARCH_CSR_PGDH		0x1a
+/* Page table base */
+#define LOONGARCH_CSR_PGD		0x1b
+#define LOONGARCH_CSR_PWCTL0		0x1c
+#define LOONGARCH_CSR_PWCTL1		0x1d
+#define LOONGARCH_CSR_STLBPGSIZE	0x1e
+#define LOONGARCH_CSR_CPUID		0x20
+#define LOONGARCH_CSR_TMID		0x40
+#define LOONGARCH_CSR_TCFG		0x41
+#define LOONGARCH_CSR_TLBRENTRY		0x88 /* TLB refill exception entry */
+/* KSave for TLB refill exception */
+#define LOONGARCH_CSR_TLBRSAVE		0x8b
+#define LOONGARCH_CSR_TLBREHI		0x8e
+#define CSR_TLBREHI_PS_SHIFT		0
+#define CSR_TLBREHI_PS			(0x3fUL << CSR_TLBREHI_PS_SHIFT)
+
+#endif
-- 
2.39.1

[PATCH v2 2/4] KVM: selftests: Add core KVM selftests support for LoongArch

[Tianrui Zhao]

Add core KVM selftests support for LoongArch.

Based-on: <20230803022138.2736430-1-zhaotianrui@loongson.cn>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 .../selftests/kvm/lib/loongarch/exception.S   |  27 ++
 .../selftests/kvm/lib/loongarch/processor.c   | 356 ++++++++++++++++++
 2 files changed, 383 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/lib/loongarch/exception.S
 create mode 100644 tools/testing/selftests/kvm/lib/loongarch/processor.c

diff --git a/tools/testing/selftests/kvm/lib/loongarch/exception.S b/tools/testing/selftests/kvm/lib/loongarch/exception.S
new file mode 100644
index 000000000000..aa1b69fe52cf
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/loongarch/exception.S
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include "processor.h"
+
+/* address of refill exception should be 4K aligned */
+.balign	4096
+.global handle_tlb_refill
+handle_tlb_refill:
+	csrwr	t0, LOONGARCH_CSR_TLBRSAVE
+	csrrd	t0, LOONGARCH_CSR_PGD
+	lddir	t0, t0, 3
+	lddir	t0, t0, 1
+	ldpte	t0, 0
+	ldpte	t0, 1
+	tlbfill
+	csrrd	t0, LOONGARCH_CSR_TLBRSAVE
+	ertn
+
+/* address of general exception should be 4K aligned */
+.balign	4096
+.global handle_exception
+handle_exception:
+1:
+	nop
+	b	1b
+	nop
+	ertn
diff --git a/tools/testing/selftests/kvm/lib/loongarch/processor.c b/tools/testing/selftests/kvm/lib/loongarch/processor.c
new file mode 100644
index 000000000000..3419e5cfd5e1
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/loongarch/processor.c
@@ -0,0 +1,356 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <assert.h>
+#include <linux/bitfield.h>
+#include <linux/compiler.h>
+
+#include "kvm_util.h"
+#include "processor.h"
+
+static uint64_t pgd_index(struct kvm_vm *vm, vm_vaddr_t gva)
+{
+	unsigned int shift;
+	uint64_t mask;
+
+	shift = (vm->pgtable_levels - 1) * (vm->page_shift - 3) + vm->page_shift;
+	mask = (1UL << (vm->va_bits - shift)) - 1;
+	return (gva >> shift) & mask;
+}
+
+static uint64_t pud_index(struct kvm_vm *vm, vm_vaddr_t gva)
+{
+	unsigned int shift;
+	uint64_t mask;
+
+	shift = 2 * (vm->page_shift - 3) + vm->page_shift;
+	mask = (1UL << (vm->page_shift - 3)) - 1;
+	TEST_ASSERT(vm->pgtable_levels == 4,
+		    "Mode %d does not have 4 page table levels", vm->mode);
+
+	return (gva >> shift) & mask;
+}
+
+static uint64_t pmd_index(struct kvm_vm *vm, vm_vaddr_t gva)
+{
+	unsigned int shift;
+	uint64_t mask;
+
+	shift = (vm->page_shift - 3) + vm->page_shift;
+	mask = (1UL << (vm->page_shift - 3)) - 1;
+	TEST_ASSERT(vm->pgtable_levels >= 3,
+		    "Mode %d does not have >= 3 page table levels", vm->mode);
+
+	return (gva >> shift) & mask;
+}
+
+static uint64_t pte_index(struct kvm_vm *vm, vm_vaddr_t gva)
+{
+	uint64_t mask;
+
+	mask = (1UL << (vm->page_shift - 3)) - 1;
+	return (gva >> vm->page_shift) & mask;
+}
+
+static uint64_t pte_addr(struct kvm_vm *vm, uint64_t entry)
+{
+	uint64_t mask;
+
+	mask = ((1UL << (vm->va_bits - vm->page_shift)) - 1) << vm->page_shift;
+	return entry & mask;
+}
+
+static uint64_t ptrs_per_pgd(struct kvm_vm *vm)
+{
+	unsigned int shift;
+
+	shift = (vm->pgtable_levels - 1) * (vm->page_shift - 3) + vm->page_shift;
+	return 1 << (vm->va_bits - shift);
+}
+
+static uint64_t __maybe_unused ptrs_per_pte(struct kvm_vm *vm)
+{
+	return 1 << (vm->page_shift - 3);
+}
+
+void virt_arch_pgd_alloc(struct kvm_vm *vm)
+{
+	if (vm->pgd_created)
+		return;
+
+	vm->pgd = vm_alloc_page_table(vm);
+	vm->pgd_created = true;
+}
+
+uint64_t *virt_get_pte_hva(struct kvm_vm *vm, vm_vaddr_t gva)
+{
+	uint64_t *ptep;
+
+	if (!vm->pgd_created)
+		goto unmapped_gva;
+
+	ptep = addr_gpa2hva(vm, vm->pgd) + pgd_index(vm, gva) * 8;
+	if (!ptep)
+		goto unmapped_gva;
+
+	switch (vm->pgtable_levels) {
+	case 4:
+		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pud_index(vm, gva) * 8;
+		if (!ptep)
+			goto unmapped_gva;
+		/* fall through */
+	case 3:
+		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pmd_index(vm, gva) * 8;
+		if (!ptep)
+			goto unmapped_gva;
+		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pte_index(vm, gva) * 8;
+		if (!ptep)
+			goto unmapped_gva;
+		break;
+	default:
+		TEST_FAIL("Got %u page table levels, expected 3 or 4", vm->pgtable_levels);
+	}
+
+	return ptep;
+
+unmapped_gva:
+	TEST_FAIL("No mapping for vm virtual address, gva: 0x%lx", gva);
+	exit(EXIT_FAILURE);
+}
+
+vm_paddr_t addr_arch_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
+{
+	uint64_t *ptep;
+
+	ptep = virt_get_pte_hva(vm, gva);
+	return pte_addr(vm, *ptep) + (gva & (vm->page_size - 1));
+}
+
+void virt_arch_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
+{
+	uint32_t prot_bits;
+	uint64_t *ptep;
+
+	TEST_ASSERT((vaddr % vm->page_size) == 0,
+			"Virtual address not on page boundary,\n"
+			"vaddr: 0x%lx vm->page_size: 0x%x", vaddr, vm->page_size);
+	TEST_ASSERT(sparsebit_is_set(vm->vpages_valid,
+			(vaddr >> vm->page_shift)),
+			"Invalid virtual address, vaddr: 0x%lx", vaddr);
+	TEST_ASSERT((paddr % vm->page_size) == 0,
+			"Physical address not on page boundary,\n"
+			"paddr: 0x%lx vm->page_size: 0x%x", paddr, vm->page_size);
+	TEST_ASSERT((paddr >> vm->page_shift) <= vm->max_gfn,
+			"Physical address beyond maximum supported,\n"
+			"paddr: 0x%lx vm->max_gfn: 0x%lx vm->page_size: 0x%x",
+			paddr, vm->max_gfn, vm->page_size);
+
+	ptep = addr_gpa2hva(vm, vm->pgd) + pgd_index(vm, vaddr) * 8;
+	if (!*ptep)
+		*ptep = vm_alloc_page_table(vm);
+
+	switch (vm->pgtable_levels) {
+	case 4:
+		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pud_index(vm, vaddr) * 8;
+		if (!*ptep)
+			*ptep = vm_alloc_page_table(vm);
+		/* fall through */
+	case 3:
+		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pmd_index(vm, vaddr) * 8;
+		if (!*ptep)
+			*ptep = vm_alloc_page_table(vm);
+		ptep = addr_gpa2hva(vm, pte_addr(vm, *ptep)) + pte_index(vm, vaddr) * 8;
+		break;
+	default:
+		TEST_FAIL("Got %u page table levels, expected 3 or 4", vm->pgtable_levels);
+	}
+
+	prot_bits = _PAGE_PRESENT | __READABLE | __WRITEABLE | _CACHE_CC;
+	prot_bits |= _PAGE_USER;
+	*ptep = paddr | prot_bits;
+}
+
+static void pte_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent, uint64_t page, int level)
+{
+#ifdef DEBUG
+	static const char * const type[] = { "", "pud", "pmd", "pte" };
+	uint64_t pte, *ptep;
+
+	if (level == 4)
+		return;
+
+	for (pte = page; pte < page + ptrs_per_pte(vm) * 8; pte += 8) {
+		ptep = addr_gpa2hva(vm, pte);
+		if (!*ptep)
+			continue;
+		fprintf(stream, "%*s%s: %lx: %lx at %p\n",
+			indent, "", type[level], pte, *ptep, ptep);
+		pte_dump(stream, vm, indent + 1, pte_addr(vm, *ptep), level + 1);
+	}
+#endif
+}
+
+void virt_arch_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
+{
+	int level;
+	uint64_t pgd, *ptep;
+
+	level = 4 - (vm->pgtable_levels - 1);
+	if (!vm->pgd_created)
+		return;
+
+	for (pgd = vm->pgd; pgd < vm->pgd + ptrs_per_pgd(vm) * 8; pgd += 8) {
+		ptep = addr_gpa2hva(vm, pgd);
+		if (!*ptep)
+			continue;
+		fprintf(stream, "%*spgd: %lx: %lx at %p\n", indent, "", pgd, *ptep, ptep);
+		pte_dump(stream, vm, indent + 1, pte_addr(vm, *ptep), level);
+	}
+}
+
+void vcpu_arch_dump(FILE *stream, struct kvm_vcpu *vcpu, uint8_t indent)
+{
+}
+
+void assert_on_unhandled_exception(struct kvm_vcpu *vcpu)
+{
+}
+
+void vcpu_args_set(struct kvm_vcpu *vcpu, unsigned int num, ...)
+{
+	va_list ap;
+	struct kvm_regs regs;
+	int i;
+
+	TEST_ASSERT(num >= 1 && num <= 8, "Unsupported number of args,\n"
+		    "num: %u\n", num);
+
+	vcpu_regs_get(vcpu, &regs);
+	va_start(ap, num);
+	for (i = 0; i < num; i++)
+		regs.gpr[i + 4] = va_arg(ap, uint64_t);
+	va_end(ap);
+	vcpu_regs_set(vcpu, &regs);
+}
+
+static void loongarch_get_csr(struct kvm_vcpu *vcpu, uint64_t id, void *addr)
+{
+	uint64_t csrid;
+
+	csrid = KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U64 | 8 * id;
+	vcpu_get_reg(vcpu, csrid, addr);
+}
+
+static void loongarch_set_csr(struct kvm_vcpu *vcpu, uint64_t id, uint64_t val)
+{
+	uint64_t csrid;
+
+	csrid = KVM_REG_LOONGARCH_CSR | KVM_REG_SIZE_U64 | 8 * id;
+	vcpu_set_reg(vcpu, csrid, val);
+}
+
+extern void handle_tlb_refill(void);
+extern void handle_exception(void);
+
+static void loongarch_vcpu_setup(struct kvm_vcpu *vcpu)
+{
+	unsigned long val;
+	int width;
+	struct kvm_vm *vm = vcpu->vm;
+
+	switch (vm->mode) {
+	case VM_MODE_P48V48_16K:
+	case VM_MODE_P40V48_16K:
+	case VM_MODE_P36V48_16K:
+	case VM_MODE_P36V47_16K:
+		break;
+
+	default:
+		TEST_FAIL("Unknown guest mode, mode: 0x%x", vm->mode);
+	}
+
+	/* user mode and page enable mode */
+	val = PLV_USER | CSR_CRMD_PG;
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_CRMD, val);
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_PRMD, val);
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_EUEN, 1);
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_ECFG, 0);
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_TCFG, 0);
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_ASID, 1);
+
+	width = vm->page_shift - 3;
+	val = 0;
+	switch (vm->pgtable_levels) {
+	case 4:
+		/* pud page shift and width */
+		val = (vm->page_shift + width * 2) << 20 | (width << 25);
+		/* fall throuth */
+	case 3:
+		/* pmd page shift and width */
+		val |= (vm->page_shift + width) << 10 | (width << 15);
+		/* pte page shift and width */
+		val |= vm->page_shift | width << 5;
+		break;
+	default:
+		TEST_FAIL("Got %u page table levels, expected 3 or 4", vm->pgtable_levels);
+	}
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_PWCTL0, val);
+
+	/* pgd page shift and width */
+	val = (vm->page_shift + width * (vm->pgtable_levels - 1)) | width << 6;
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_PWCTL1, val);
+
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_PGDL, vm->pgd);
+
+	/*
+	 * refill exception runs on real mode, entry address should
+	 * be physical address
+	 */
+	val = addr_gva2gpa(vm, (unsigned long)handle_tlb_refill);
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_TLBRENTRY, val);
+
+	/*
+	 * general exception runs on page-enabled mode, entry address should
+	 * be virtual address
+	 */
+	val = (unsigned long)handle_exception;
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_EENTRY, val);
+
+	loongarch_get_csr(vcpu, LOONGARCH_CSR_TLBIDX, &val);
+	val &= ~CSR_TLBIDX_SIZEM;
+	val |= PS_DEFAULT_SIZE << CSR_TLBIDX_SIZE;
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_TLBIDX, val);
+
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_STLBPGSIZE, PS_DEFAULT_SIZE);
+
+	loongarch_get_csr(vcpu, LOONGARCH_CSR_TLBREHI, &val);
+	val &= ~CSR_TLBREHI_PS;
+	val |= PS_DEFAULT_SIZE << CSR_TLBREHI_PS_SHIFT;
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_TLBREHI, val);
+
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_CPUID, vcpu->id);
+	loongarch_set_csr(vcpu, LOONGARCH_CSR_TMID,  vcpu->id);
+}
+
+struct kvm_vcpu *vm_arch_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id,
+				  void *guest_code)
+{
+	size_t stack_size;
+	uint64_t stack_vaddr;
+	struct kvm_regs regs;
+	struct kvm_vcpu *vcpu;
+
+	vcpu = __vm_vcpu_add(vm, vcpu_id);
+	stack_size = vm->page_size;
+	stack_vaddr = __vm_vaddr_alloc(vm, stack_size,
+			DEFAULT_GUEST_STACK_VADDR_MIN,
+			MEM_REGION_DATA);
+
+	loongarch_vcpu_setup(vcpu);
+	/* Setup guest general purpose registers */
+	vcpu_regs_get(vcpu, &regs);
+	regs.gpr[3] = stack_vaddr + stack_size - 8;
+	regs.pc = (uint64_t)guest_code;
+	vcpu_regs_set(vcpu, &regs);
+
+	return vcpu;
+}
-- 
2.39.1

[PATCH v2 3/4] KVM: selftests: Add ucall test support for LoongArch

[Tianrui Zhao]

Add ucall test support for LoongArch. A ucall is a "hypercall to
userspace".

Based-on: <20230803022138.2736430-1-zhaotianrui@loongson.cn>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 .../selftests/kvm/lib/loongarch/ucall.c       | 43 +++++++++++++++++++
 1 file changed, 43 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/lib/loongarch/ucall.c

diff --git a/tools/testing/selftests/kvm/lib/loongarch/ucall.c b/tools/testing/selftests/kvm/lib/loongarch/ucall.c
new file mode 100644
index 000000000000..72868ddec313
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/loongarch/ucall.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ucall support. A ucall is a "hypercall to userspace".
+ *
+ */
+#include "kvm_util.h"
+
+/*
+ * ucall_exit_mmio_addr holds per-VM values (global data is duplicated by each
+ * VM), it must not be accessed from host code.
+ */
+static vm_vaddr_t *ucall_exit_mmio_addr;
+
+void ucall_arch_init(struct kvm_vm *vm, vm_paddr_t mmio_gpa)
+{
+	vm_vaddr_t mmio_gva = vm_vaddr_unused_gap(vm, vm->page_size, KVM_UTIL_MIN_VADDR);
+
+	virt_map(vm, mmio_gva, mmio_gpa, 1);
+
+	vm->ucall_mmio_addr = mmio_gpa;
+
+	write_guest_global(vm, ucall_exit_mmio_addr, (vm_vaddr_t *)mmio_gva);
+}
+
+void ucall_arch_do_ucall(vm_vaddr_t uc)
+{
+	WRITE_ONCE(*ucall_exit_mmio_addr, uc);
+}
+
+void *ucall_arch_get_ucall(struct kvm_vcpu *vcpu)
+{
+	struct kvm_run *run = vcpu->run;
+
+	if (run->exit_reason == KVM_EXIT_MMIO &&
+	    run->mmio.phys_addr == vcpu->vm->ucall_mmio_addr) {
+		TEST_ASSERT(run->mmio.is_write && run->mmio.len == sizeof(uint64_t),
+			    "Unexpected ucall exit mmio address access");
+
+		return (void *)(*((uint64_t *)run->mmio.data));
+	}
+
+	return NULL;
+}
-- 
2.39.1

[PATCH v2 4/4] KVM: selftests: Add test cases supported by LoongArch into makefile

[Tianrui Zhao]

Add test cases supported by LoongArch into makefile.
LoongArch supports some KVM common tests, such as:
  kvm_create_max_vcpus
  demand_paging_test
  kvm_page_table_test
  set_memory_region_test
  memslot_modification_stress_test
  memslot_perf_test
  kvm_binary_stats_test
And some test cases are not supported by LoongArch. for example,
we do not support the rseq_test, as the glibc do not support it.

Based-on: <20230803022138.2736430-1-zhaotianrui@loongson.cn>
Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
---
 tools/testing/selftests/kvm/Makefile | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index c692cc86e7da..96bf53565a32 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -55,6 +55,10 @@ LIBKVM_s390x += lib/s390x/ucall.c
 LIBKVM_riscv += lib/riscv/processor.c
 LIBKVM_riscv += lib/riscv/ucall.c
 
+LIBKVM_loongarch += lib/loongarch/processor.c
+LIBKVM_loongarch += lib/loongarch/ucall.c
+LIBKVM_loongarch += lib/loongarch/exception.S
+
 # Non-compiled test targets
 TEST_PROGS_x86_64 += x86_64/nx_huge_pages_test.sh
 
@@ -181,6 +185,14 @@ TEST_GEN_PROGS_riscv += kvm_page_table_test
 TEST_GEN_PROGS_riscv += set_memory_region_test
 TEST_GEN_PROGS_riscv += kvm_binary_stats_test
 
+TEST_GEN_PROGS_loongarch += kvm_create_max_vcpus
+TEST_GEN_PROGS_loongarch += demand_paging_test
+TEST_GEN_PROGS_loongarch += kvm_page_table_test
+TEST_GEN_PROGS_loongarch += set_memory_region_test
+TEST_GEN_PROGS_loongarch += memslot_modification_stress_test
+TEST_GEN_PROGS_loongarch += memslot_perf_test
+TEST_GEN_PROGS_loongarch += kvm_binary_stats_test
+
 TEST_PROGS += $(TEST_PROGS_$(ARCH_DIR))
 TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(ARCH_DIR))
 TEST_GEN_PROGS_EXTENDED += $(TEST_GEN_PROGS_EXTENDED_$(ARCH_DIR))
-- 
2.39.1

Re: [PATCH v2 3/4] KVM: selftests: Add ucall test support for LoongArch

[Sean Christopherson]

On Mon, Aug 07, 2023, Tianrui Zhao wrote:
> Add ucall test support for LoongArch. A ucall is a "hypercall to
> userspace".

Nit, can you explain why LoongArch uses MMIO to trigger ucall, and what alternatives
were considred (if any)?  The main reason for the ask is because we've tossed
around the idea of converting all architectures (except s390) to MMIO-based ucall
in order to reduce the number of "flavors" of ucall we have to worry about it.
If MMIO is the only reasonable choice for LoongArch, that's another reason to
double down on MMIO as the primary choice for ucall.

> Based-on: <20230803022138.2736430-1-zhaotianrui@loongson.cn>
> Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
> ---
>  .../selftests/kvm/lib/loongarch/ucall.c       | 43 +++++++++++++++++++
>  1 file changed, 43 insertions(+)
>  create mode 100644 tools/testing/selftests/kvm/lib/loongarch/ucall.c
> 
> diff --git a/tools/testing/selftests/kvm/lib/loongarch/ucall.c b/tools/testing/selftests/kvm/lib/loongarch/ucall.c
> new file mode 100644
> index 000000000000..72868ddec313
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/loongarch/ucall.c
> @@ -0,0 +1,43 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ucall support. A ucall is a "hypercall to userspace".
> + *
> + */
> +#include "kvm_util.h"
> +
> +/*
> + * ucall_exit_mmio_addr holds per-VM values (global data is duplicated by each
> + * VM), it must not be accessed from host code.
> + */
> +static vm_vaddr_t *ucall_exit_mmio_addr;
> +
> +void ucall_arch_init(struct kvm_vm *vm, vm_paddr_t mmio_gpa)
> +{
> +	vm_vaddr_t mmio_gva = vm_vaddr_unused_gap(vm, vm->page_size, KVM_UTIL_MIN_VADDR);
> +
> +	virt_map(vm, mmio_gva, mmio_gpa, 1);
> +
> +	vm->ucall_mmio_addr = mmio_gpa;
> +
> +	write_guest_global(vm, ucall_exit_mmio_addr, (vm_vaddr_t *)mmio_gva);
> +}
> +
> +void ucall_arch_do_ucall(vm_vaddr_t uc)
> +{
> +	WRITE_ONCE(*ucall_exit_mmio_addr, uc);

Another uber nit, you might want to put this in the header as a static inline to
avoid function calls.  I doubt it'll actually matter, but we've had enough weird,
hard-to-debug issues with ucall that minimizing the amount of generated code might
save some future pain.

Re: [PATCH v2 3/4] KVM: selftests: Add ucall test support for LoongArch

[zhaotianrui]

在 2023/9/28 上午4:54, Sean Christopherson 写道:
> On Mon, Aug 07, 2023, Tianrui Zhao wrote:
>> Add ucall test support for LoongArch. A ucall is a "hypercall to
>> userspace".
> Nit, can you explain why LoongArch uses MMIO to trigger ucall, and what alternatives
> were considred (if any)?  The main reason for the ask is because we've tossed
> around the idea of converting all architectures (except s390) to MMIO-based ucall
> in order to reduce the number of "flavors" of ucall we have to worry about it.
> If MMIO is the only reasonable choice for LoongArch, that's another reason to
> double down on MMIO as the primary choice for ucall.
Thanks for your reminding about ucall, and our guest can also use 
hypercall instruction to trigger ucall, so this change will not affect us.

Thanks
Tianrui Zhao
>
>> Based-on: <20230803022138.2736430-1-zhaotianrui@loongson.cn>
>> Signed-off-by: Tianrui Zhao <zhaotianrui@loongson.cn>
>> ---
>>   .../selftests/kvm/lib/loongarch/ucall.c       | 43 +++++++++++++++++++
>>   1 file changed, 43 insertions(+)
>>   create mode 100644 tools/testing/selftests/kvm/lib/loongarch/ucall.c
>>
>> diff --git a/tools/testing/selftests/kvm/lib/loongarch/ucall.c b/tools/testing/selftests/kvm/lib/loongarch/ucall.c
>> new file mode 100644
>> index 000000000000..72868ddec313
>> --- /dev/null
>> +++ b/tools/testing/selftests/kvm/lib/loongarch/ucall.c
>> @@ -0,0 +1,43 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * ucall support. A ucall is a "hypercall to userspace".
>> + *
>> + */
>> +#include "kvm_util.h"
>> +
>> +/*
>> + * ucall_exit_mmio_addr holds per-VM values (global data is duplicated by each
>> + * VM), it must not be accessed from host code.
>> + */
>> +static vm_vaddr_t *ucall_exit_mmio_addr;
>> +
>> +void ucall_arch_init(struct kvm_vm *vm, vm_paddr_t mmio_gpa)
>> +{
>> +	vm_vaddr_t mmio_gva = vm_vaddr_unused_gap(vm, vm->page_size, KVM_UTIL_MIN_VADDR);
>> +
>> +	virt_map(vm, mmio_gva, mmio_gpa, 1);
>> +
>> +	vm->ucall_mmio_addr = mmio_gpa;
>> +
>> +	write_guest_global(vm, ucall_exit_mmio_addr, (vm_vaddr_t *)mmio_gva);
>> +}
>> +
>> +void ucall_arch_do_ucall(vm_vaddr_t uc)
>> +{
>> +	WRITE_ONCE(*ucall_exit_mmio_addr, uc);
> Another uber nit, you might want to put this in the header as a static inline to
> avoid function calls.  I doubt it'll actually matter, but we've had enough weird,
> hard-to-debug issues with ucall that minimizing the amount of generated code might
> save some future pain.