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authorMartin K. Petersen <martin.petersen@oracle.com>2025-11-20 10:26:13 -0500
committerMartin K. Petersen <martin.petersen@oracle.com>2025-11-20 10:26:13 -0500
commit82f78acd5a9270370ef4aa3f032ede25f3dc91ee (patch)
treea0aa5f6ed6b9af6e270557ecdea2e2839c1ed2e2 /tools/testing/selftests/kvm/pre_fault_memory_test.c
parent38725491e7665640545c8155db53a7b21bcdf886 (diff)
parentb06b8c421485e0e96d7fd6aa614fb0b6f2778a03 (diff)
Merge patch series "Add OP-TEE based RPMB driver for UFS devices"
Bean Huo <beanhuo@iokpp.de> says: This patch series introduces OP-TEE based RPMB (Replay Protected Memory Block) support for UFS devices, extending the kernel-level secure storage capabilities that are currently available for eMMC devices. Previously, OP-TEE required a userspace supplicant to access RPMB partitions, which created complex dependencies and reliability issues, especially during early boot scenarios. Recent work by Linaro has moved core supplicant functionality directly into the Linux kernel for eMMC devices, eliminating userspace dependencies and enabling immediate secure storage access. This series extends the same approach to UFS devices, which are used in enterprise and mobile applications that require secure storage capabilities. Benefits: - Eliminates dependency on userspace supplicant for UFS RPMB access - Enables early boot secure storage access (e.g., fTPM, secure UEFI variables) - Provides kernel-level RPMB access as soon as UFS driver is initialized - Removes complex initramfs dependencies and boot ordering requirements - Ensures reliable and deterministic secure storage operations - Supports both built-in and modular fTPM configurations. Prerequisites: -------------- This patch series depends on commit 7e8242405b94 ("rpmb: move struct rpmb_frame to common header") which has been merged into mainline v6.18-rc2. Link: https://patch.msgid.link/20251107230518.4060231-1-beanhuo@iokpp.de Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Diffstat (limited to 'tools/testing/selftests/kvm/pre_fault_memory_test.c')
-rw-r--r--tools/testing/selftests/kvm/pre_fault_memory_test.c131
1 files changed, 114 insertions, 17 deletions
diff --git a/tools/testing/selftests/kvm/pre_fault_memory_test.c b/tools/testing/selftests/kvm/pre_fault_memory_test.c
index 0350a8896a2f..f04768c1d2e4 100644
--- a/tools/testing/selftests/kvm/pre_fault_memory_test.c
+++ b/tools/testing/selftests/kvm/pre_fault_memory_test.c
@@ -10,6 +10,7 @@
#include <test_util.h>
#include <kvm_util.h>
#include <processor.h>
+#include <pthread.h>
/* Arbitrarily chosen values */
#define TEST_SIZE (SZ_2M + PAGE_SIZE)
@@ -30,18 +31,66 @@ static void guest_code(uint64_t base_gpa)
GUEST_DONE();
}
-static void pre_fault_memory(struct kvm_vcpu *vcpu, u64 gpa, u64 size,
- u64 left)
+struct slot_worker_data {
+ struct kvm_vm *vm;
+ u64 gpa;
+ uint32_t flags;
+ bool worker_ready;
+ bool prefault_ready;
+ bool recreate_slot;
+};
+
+static void *delete_slot_worker(void *__data)
+{
+ struct slot_worker_data *data = __data;
+ struct kvm_vm *vm = data->vm;
+
+ WRITE_ONCE(data->worker_ready, true);
+
+ while (!READ_ONCE(data->prefault_ready))
+ cpu_relax();
+
+ vm_mem_region_delete(vm, TEST_SLOT);
+
+ while (!READ_ONCE(data->recreate_slot))
+ cpu_relax();
+
+ vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, data->gpa,
+ TEST_SLOT, TEST_NPAGES, data->flags);
+
+ return NULL;
+}
+
+static void pre_fault_memory(struct kvm_vcpu *vcpu, u64 base_gpa, u64 offset,
+ u64 size, u64 expected_left, bool private)
{
struct kvm_pre_fault_memory range = {
- .gpa = gpa,
+ .gpa = base_gpa + offset,
.size = size,
.flags = 0,
};
- u64 prev;
+ struct slot_worker_data data = {
+ .vm = vcpu->vm,
+ .gpa = base_gpa,
+ .flags = private ? KVM_MEM_GUEST_MEMFD : 0,
+ };
+ bool slot_recreated = false;
+ pthread_t slot_worker;
int ret, save_errno;
+ u64 prev;
+
+ /*
+ * Concurrently delete (and recreate) the slot to test KVM's handling
+ * of a racing memslot deletion with prefaulting.
+ */
+ pthread_create(&slot_worker, NULL, delete_slot_worker, &data);
- do {
+ while (!READ_ONCE(data.worker_ready))
+ cpu_relax();
+
+ WRITE_ONCE(data.prefault_ready, true);
+
+ for (;;) {
prev = range.size;
ret = __vcpu_ioctl(vcpu, KVM_PRE_FAULT_MEMORY, &range);
save_errno = errno;
@@ -49,18 +98,65 @@ static void pre_fault_memory(struct kvm_vcpu *vcpu, u64 gpa, u64 size,
"%sexpecting range.size to change on %s",
ret < 0 ? "not " : "",
ret < 0 ? "failure" : "success");
- } while (ret >= 0 ? range.size : save_errno == EINTR);
- TEST_ASSERT(range.size == left,
- "Completed with %lld bytes left, expected %" PRId64,
- range.size, left);
+ /*
+ * Immediately retry prefaulting if KVM was interrupted by an
+ * unrelated signal/event.
+ */
+ if (ret < 0 && save_errno == EINTR)
+ continue;
+
+ /*
+ * Tell the worker to recreate the slot in order to complete
+ * prefaulting (if prefault didn't already succeed before the
+ * slot was deleted) and/or to prepare for the next testcase.
+ * Wait for the worker to exit so that the next invocation of
+ * prefaulting is guaranteed to complete (assuming no KVM bugs).
+ */
+ if (!slot_recreated) {
+ WRITE_ONCE(data.recreate_slot, true);
+ pthread_join(slot_worker, NULL);
+ slot_recreated = true;
+
+ /*
+ * Retry prefaulting to get a stable result, i.e. to
+ * avoid seeing random EAGAIN failures. Don't retry if
+ * prefaulting already succeeded, as KVM disallows
+ * prefaulting with size=0, i.e. blindly retrying would
+ * result in test failures due to EINVAL. KVM should
+ * always return success if all bytes are prefaulted,
+ * i.e. there is no need to guard against EAGAIN being
+ * returned.
+ */
+ if (range.size)
+ continue;
+ }
+
+ /*
+ * All done if there are no remaining bytes to prefault, or if
+ * prefaulting failed (EINTR was handled above, and EAGAIN due
+ * to prefaulting a memslot that's being actively deleted should
+ * be impossible since the memslot has already been recreated).
+ */
+ if (!range.size || ret < 0)
+ break;
+ }
- if (left == 0)
- __TEST_ASSERT_VM_VCPU_IOCTL(!ret, "KVM_PRE_FAULT_MEMORY", ret, vcpu->vm);
+ TEST_ASSERT(range.size == expected_left,
+ "Completed with %llu bytes left, expected %lu",
+ range.size, expected_left);
+
+ /*
+ * Assert success if prefaulting the entire range should succeed, i.e.
+ * complete with no bytes remaining. Otherwise prefaulting should have
+ * failed due to ENOENT (due to RET_PF_EMULATE for emulated MMIO when
+ * no memslot exists).
+ */
+ if (!expected_left)
+ TEST_ASSERT_VM_VCPU_IOCTL(!ret, KVM_PRE_FAULT_MEMORY, ret, vcpu->vm);
else
- /* No memory slot causes RET_PF_EMULATE. it results in -ENOENT. */
- __TEST_ASSERT_VM_VCPU_IOCTL(ret && save_errno == ENOENT,
- "KVM_PRE_FAULT_MEMORY", ret, vcpu->vm);
+ TEST_ASSERT_VM_VCPU_IOCTL(ret && save_errno == ENOENT,
+ KVM_PRE_FAULT_MEMORY, ret, vcpu->vm);
}
static void __test_pre_fault_memory(unsigned long vm_type, bool private)
@@ -97,9 +193,10 @@ static void __test_pre_fault_memory(unsigned long vm_type, bool private)
if (private)
vm_mem_set_private(vm, guest_test_phys_mem, TEST_SIZE);
- pre_fault_memory(vcpu, guest_test_phys_mem, SZ_2M, 0);
- pre_fault_memory(vcpu, guest_test_phys_mem + SZ_2M, PAGE_SIZE * 2, PAGE_SIZE);
- pre_fault_memory(vcpu, guest_test_phys_mem + TEST_SIZE, PAGE_SIZE, PAGE_SIZE);
+
+ pre_fault_memory(vcpu, guest_test_phys_mem, 0, SZ_2M, 0, private);
+ pre_fault_memory(vcpu, guest_test_phys_mem, SZ_2M, PAGE_SIZE * 2, PAGE_SIZE, private);
+ pre_fault_memory(vcpu, guest_test_phys_mem, TEST_SIZE, PAGE_SIZE, PAGE_SIZE, private);
vcpu_args_set(vcpu, 1, guest_test_virt_mem);
vcpu_run(vcpu);