Merge tag 'kvm-x86-selftests-6.7-rcN' of https://github.com/kvm-x86/linux into HEAD

KVM selftests fixes for 6.8 merge window:

 - Fix an annoying goof where the NX hugepage test prints out garbage
   instead of the magic token needed to run the text.

 - Fix build errors when a header is delete/moved due to a missing flag
   in the Makefile.

 - Detect if KVM bugged/killed a selftest's VM and print out a helpful
   message instead of complaining that a random ioctl() failed.

 - Annotate the guest printf/assert helpers with __printf(), and fix the
   various bugs that were lurking due to lack of said annotation.

A small subset of these was included in 6.7-rc as well.

Author: bonzini

tools/testing/selftests/kvm/Makefile

@@ -86,7 +86,6 @@ TEST_GEN_PROGS_x86_64 += x86_64/hyperv_svm_test
 TEST_GEN_PROGS_x86_64 += x86_64/hyperv_tlb_flush
 TEST_GEN_PROGS_x86_64 += x86_64/kvm_clock_test
 TEST_GEN_PROGS_x86_64 += x86_64/kvm_pv_test
-TEST_GEN_PROGS_x86_64 += x86_64/mmio_warning_test
 TEST_GEN_PROGS_x86_64 += x86_64/monitor_mwait_test
 TEST_GEN_PROGS_x86_64 += x86_64/nested_exceptions_test
 TEST_GEN_PROGS_x86_64 += x86_64/platform_info_test
@@ -226,7 +225,7 @@ else
 LINUX_TOOL_ARCH_INCLUDE = $(top_srcdir)/tools/arch/$(ARCH)/include
 endif
 CFLAGS += -Wall -Wstrict-prototypes -Wuninitialized -O2 -g -std=gnu99 \
-	-Wno-gnu-variable-sized-type-not-at-end -MD\
+	-Wno-gnu-variable-sized-type-not-at-end -MD -MP \
 	-fno-builtin-memcmp -fno-builtin-memcpy -fno-builtin-memset \
 	-fno-builtin-strnlen \
 	-fno-stack-protector -fno-PIE -I$(LINUX_TOOL_INCLUDE) \

tools/testing/selftests/kvm/include/kvm_util_base.h

@@ -267,6 +267,13 @@ static inline bool kvm_has_cap(long cap)
 #define __KVM_SYSCALL_ERROR(_name, _ret) \
 	"%s failed, rc: %i errno: %i (%s)", (_name), (_ret), errno, strerror(errno)
 
+/*
+ * Use the "inner", double-underscore macro when reporting errors from within
+ * other macros so that the name of ioctl() and not its literal numeric value
+ * is printed on error.  The "outer" macro is strongly preferred when reporting
+ * errors "directly", i.e. without an additional layer of macros, as it reduces
+ * the probability of passing in the wrong string.
+ */
 #define __KVM_IOCTL_ERROR(_name, _ret)	__KVM_SYSCALL_ERROR(_name, _ret)
 #define KVM_IOCTL_ERROR(_ioctl, _ret) __KVM_IOCTL_ERROR(#_ioctl, _ret)
 
@@ -279,17 +286,13 @@ static inline bool kvm_has_cap(long cap)
 #define __kvm_ioctl(kvm_fd, cmd, arg)				\
 	kvm_do_ioctl(kvm_fd, cmd, arg)
 
-
-#define _kvm_ioctl(kvm_fd, cmd, name, arg)			\
+#define kvm_ioctl(kvm_fd, cmd, arg)				\
 ({								\
 	int ret = __kvm_ioctl(kvm_fd, cmd, arg);		\
 								\
-	TEST_ASSERT(!ret, __KVM_IOCTL_ERROR(name, ret));	\
+	TEST_ASSERT(!ret, __KVM_IOCTL_ERROR(#cmd, ret));	\
 })
 
-#define kvm_ioctl(kvm_fd, cmd, arg) \
-	_kvm_ioctl(kvm_fd, cmd, #cmd, arg)
-
 static __always_inline void static_assert_is_vm(struct kvm_vm *vm) { }
 
 #define __vm_ioctl(vm, cmd, arg)				\
@@ -298,17 +301,42 @@ static __always_inline void static_assert_is_vm(struct kvm_vm *vm) { }
 	kvm_do_ioctl((vm)->fd, cmd, arg);			\
 })
 
-#define _vm_ioctl(vm, cmd, name, arg)				\
+/*
+ * Assert that a VM or vCPU ioctl() succeeded, with extra magic to detect if
+ * the ioctl() failed because KVM killed/bugged the VM.  To detect a dead VM,
+ * probe KVM_CAP_USER_MEMORY, which (a) has been supported by KVM since before
+ * selftests existed and (b) should never outright fail, i.e. is supposed to
+ * return 0 or 1.  If KVM kills a VM, KVM returns -EIO for all ioctl()s for the
+ * VM and its vCPUs, including KVM_CHECK_EXTENSION.
+ */
+#define __TEST_ASSERT_VM_VCPU_IOCTL(cond, name, ret, vm)				\
+do {											\
+	int __errno = errno;								\
+											\
+	static_assert_is_vm(vm);							\
+											\
+	if (cond)									\
+		break;									\
+											\
+	if (errno == EIO &&								\
+	    __vm_ioctl(vm, KVM_CHECK_EXTENSION, (void *)KVM_CAP_USER_MEMORY) < 0) {	\
+		TEST_ASSERT(errno == EIO, "KVM killed the VM, should return -EIO");	\
+		TEST_FAIL("KVM killed/bugged the VM, check the kernel log for clues");	\
+	}										\
+	errno = __errno;								\
+	TEST_ASSERT(cond, __KVM_IOCTL_ERROR(name, ret));				\
+} while (0)
+
+#define TEST_ASSERT_VM_VCPU_IOCTL(cond, cmd, ret, vm)		\
+	__TEST_ASSERT_VM_VCPU_IOCTL(cond, #cmd, ret, vm)
+
+#define vm_ioctl(vm, cmd, arg)					\
 ({								\
 	int ret = __vm_ioctl(vm, cmd, arg);			\
 								\
-	TEST_ASSERT(!ret, __KVM_IOCTL_ERROR(name, ret));	\
+	__TEST_ASSERT_VM_VCPU_IOCTL(!ret, #cmd, ret, vm);		\
 })
 
-#define vm_ioctl(vm, cmd, arg)					\
-	_vm_ioctl(vm, cmd, #cmd, arg)
-
-
 static __always_inline void static_assert_is_vcpu(struct kvm_vcpu *vcpu) { }
 
 #define __vcpu_ioctl(vcpu, cmd, arg)				\
@@ -317,16 +345,13 @@ static __always_inline void static_assert_is_vcpu(struct kvm_vcpu *vcpu) { }
 	kvm_do_ioctl((vcpu)->fd, cmd, arg);			\
 })
 
-#define _vcpu_ioctl(vcpu, cmd, name, arg)			\
+#define vcpu_ioctl(vcpu, cmd, arg)				\
 ({								\
 	int ret = __vcpu_ioctl(vcpu, cmd, arg);			\
 								\
-	TEST_ASSERT(!ret, __KVM_IOCTL_ERROR(name, ret));	\
+	__TEST_ASSERT_VM_VCPU_IOCTL(!ret, #cmd, ret, (vcpu)->vm);	\
 })
 
-#define vcpu_ioctl(vcpu, cmd, arg)				\
-	_vcpu_ioctl(vcpu, cmd, #cmd, arg)
-
 /*
  * Looks up and returns the value corresponding to the capability
  * (KVM_CAP_*) given by cap.
@@ -335,7 +360,7 @@ static inline int vm_check_cap(struct kvm_vm *vm, long cap)
 {
 	int ret =  __vm_ioctl(vm, KVM_CHECK_EXTENSION, (void *)cap);
 
-	TEST_ASSERT(ret >= 0, KVM_IOCTL_ERROR(KVM_CHECK_EXTENSION, ret));
+	TEST_ASSERT_VM_VCPU_IOCTL(ret >= 0, KVM_CHECK_EXTENSION, ret, vm);
 	return ret;
 }
 
@@ -442,7 +467,7 @@ static inline int vm_get_stats_fd(struct kvm_vm *vm)
 {
 	int fd = __vm_ioctl(vm, KVM_GET_STATS_FD, NULL);
 
-	TEST_ASSERT(fd >= 0, KVM_IOCTL_ERROR(KVM_GET_STATS_FD, fd));
+	TEST_ASSERT_VM_VCPU_IOCTL(fd >= 0, KVM_GET_STATS_FD, fd, vm);
 	return fd;
 }
 
@@ -684,7 +709,7 @@ static inline int vcpu_get_stats_fd(struct kvm_vcpu *vcpu)
 {
 	int fd = __vcpu_ioctl(vcpu, KVM_GET_STATS_FD, NULL);
 
-	TEST_ASSERT(fd >= 0, KVM_IOCTL_ERROR(KVM_GET_STATS_FD, fd));
+	TEST_ASSERT_VM_VCPU_IOCTL(fd >= 0, KVM_CHECK_EXTENSION, fd, vcpu->vm);
 	return fd;
 }
 

tools/testing/selftests/kvm/include/test_util.h

@@ -191,7 +191,7 @@ static inline uint32_t atoi_non_negative(const char *name, const char *num_str)
 }
 
 int guest_vsnprintf(char *buf, int n, const char *fmt, va_list args);
-int guest_snprintf(char *buf, int n, const char *fmt, ...);
+__printf(3, 4) int guest_snprintf(char *buf, int n, const char *fmt, ...);
 
 char *strdup_printf(const char *fmt, ...) __attribute__((format(printf, 1, 2), nonnull(1)));
 

tools/testing/selftests/kvm/include/ucall_common.h

@@ -34,9 +34,10 @@ void ucall_arch_do_ucall(vm_vaddr_t uc);
 void *ucall_arch_get_ucall(struct kvm_vcpu *vcpu);
 
 void ucall(uint64_t cmd, int nargs, ...);
-void ucall_fmt(uint64_t cmd, const char *fmt, ...);
-void ucall_assert(uint64_t cmd, const char *exp, const char *file,
-		  unsigned int line, const char *fmt, ...);
+__printf(2, 3) void ucall_fmt(uint64_t cmd, const char *fmt, ...);
+__printf(5, 6) void ucall_assert(uint64_t cmd, const char *exp,
+				 const char *file, unsigned int line,
+				 const char *fmt, ...);
 uint64_t get_ucall(struct kvm_vcpu *vcpu, struct ucall *uc);
 void ucall_init(struct kvm_vm *vm, vm_paddr_t mmio_gpa);
 int ucall_nr_pages_required(uint64_t page_size);

tools/testing/selftests/kvm/lib/kvm_util.c

@@ -1271,7 +1271,7 @@ struct kvm_vcpu *__vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpu_id)
 	vcpu->vm = vm;
 	vcpu->id = vcpu_id;
 	vcpu->fd = __vm_ioctl(vm, KVM_CREATE_VCPU, (void *)(unsigned long)vcpu_id);
-	TEST_ASSERT(vcpu->fd >= 0, KVM_IOCTL_ERROR(KVM_CREATE_VCPU, vcpu->fd));
+	TEST_ASSERT_VM_VCPU_IOCTL(vcpu->fd >= 0, KVM_CREATE_VCPU, vcpu->fd, vm);
 
 	TEST_ASSERT(vcpu_mmap_sz() >= sizeof(*vcpu->run), "vcpu mmap size "
 		"smaller than expected, vcpu_mmap_sz: %i expected_min: %zi",

tools/testing/selftests/kvm/set_memory_region_test.c

@@ -157,17 +157,17 @@ static void guest_code_move_memory_region(void)
 	 */
 	val = guest_spin_on_val(0);
 	__GUEST_ASSERT(val == 1 || val == MMIO_VAL,
-		       "Expected '1' or MMIO ('%llx'), got '%llx'", MMIO_VAL, val);
+		       "Expected '1' or MMIO ('%lx'), got '%lx'", MMIO_VAL, val);
 
 	/* Spin until the misaligning memory region move completes. */
 	val = guest_spin_on_val(MMIO_VAL);
 	__GUEST_ASSERT(val == 1 || val == 0,
-		       "Expected '0' or '1' (no MMIO), got '%llx'", val);
+		       "Expected '0' or '1' (no MMIO), got '%lx'", val);
 
 	/* Spin until the memory region starts to get re-aligned. */
 	val = guest_spin_on_val(0);
 	__GUEST_ASSERT(val == 1 || val == MMIO_VAL,
-		       "Expected '1' or MMIO ('%llx'), got '%llx'", MMIO_VAL, val);
+		       "Expected '1' or MMIO ('%lx'), got '%lx'", MMIO_VAL, val);
 
 	/* Spin until the re-aligning memory region move completes. */
 	val = guest_spin_on_val(MMIO_VAL);

tools/testing/selftests/kvm/x86_64/hyperv_features.c

@@ -55,18 +55,18 @@ static void guest_msr(struct msr_data *msr)
 	if (msr->fault_expected)
 		__GUEST_ASSERT(vector == GP_VECTOR,
 			       "Expected #GP on %sMSR(0x%x), got vector '0x%x'",
-			       msr->idx, msr->write ? "WR" : "RD", vector);
+			       msr->write ? "WR" : "RD", msr->idx, vector);
 	else
 		__GUEST_ASSERT(!vector,
 			       "Expected success on %sMSR(0x%x), got vector '0x%x'",
-			       msr->idx, msr->write ? "WR" : "RD", vector);
+			       msr->write ? "WR" : "RD", msr->idx, vector);
 
 	if (vector || is_write_only_msr(msr->idx))
 		goto done;
 
 	if (msr->write)
 		__GUEST_ASSERT(!vector,
-			       "WRMSR(0x%x) to '0x%llx', RDMSR read '0x%llx'",
+			       "WRMSR(0x%x) to '0x%lx', RDMSR read '0x%lx'",
 			       msr->idx, msr->write_val, msr_val);
 
 	/* Invariant TSC bit appears when TSC invariant control MSR is written to */
@@ -102,11 +102,11 @@ static void guest_hcall(vm_vaddr_t pgs_gpa, struct hcall_data *hcall)
 	vector = __hyperv_hypercall(hcall->control, input, output, &res);
 	if (hcall->ud_expected) {
 		__GUEST_ASSERT(vector == UD_VECTOR,
-			       "Expected #UD for control '%u', got vector '0x%x'",
+			       "Expected #UD for control '%lu', got vector '0x%x'",
 			       hcall->control, vector);
 	} else {
 		__GUEST_ASSERT(!vector,
-			       "Expected no exception for control '%u', got vector '0x%x'",
+			       "Expected no exception for control '%lu', got vector '0x%x'",
 			       hcall->control, vector);
 		GUEST_ASSERT_EQ(res, hcall->expect);
 	}

tools/testing/selftests/kvm/x86_64/mmio_warning_test.c

@@ -27,10 +27,12 @@ do {									\
 									\
 	if (fault_wanted)						\
 		__GUEST_ASSERT((vector) == UD_VECTOR,			\
-			       "Expected #UD on " insn " for testcase '0x%x', got '0x%x'", vector); \
+			       "Expected #UD on " insn " for testcase '0x%x', got '0x%x'", \
+			       testcase, vector);			\
 	else								\
 		__GUEST_ASSERT(!(vector),				\
-			       "Expected success on " insn " for testcase '0x%x', got '0x%x'", vector); \
+			       "Expected success on " insn " for testcase '0x%x', got '0x%x'", \
+			       testcase, vector);			\
 } while (0)
 
 static void guest_monitor_wait(int testcase)

tools/testing/selftests/kvm/x86_64/monitor_mwait_test.c

@@ -259,7 +259,7 @@ int main(int argc, char **argv)
 	__TEST_REQUIRE(token == MAGIC_TOKEN,
 		       "This test must be run with the magic token %d.\n"
 		       "This is done by nx_huge_pages_test.sh, which\n"
-		       "also handles environment setup for the test.");
+		       "also handles environment setup for the test.", MAGIC_TOKEN);
 
 	run_test(reclaim_period_ms, false, reboot_permissions);
 	run_test(reclaim_period_ms, true, reboot_permissions);