[PATCH v5 01/10] hyperv: Convert Hyper-V status codes to strings

Nuno Das Neves
2025-02-26T23:08:59Z

Introduce hv_result_to_string() for this purpose. This allows
hypercall failures to be debugged more easily with dmesg.

Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
---
drivers/hv/hv_common.c | 65 ++++++++++++++++++++++++++++++++++
drivers/hv/hv_proc.c | 13 ++++---
include/asm-generic/mshyperv.h | 1 +
3 files changed, 74 insertions(+), 5 deletions(-)

diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 9804adb4cc56..ce20818688fe 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -740,3 +740,68 @@ void hv_identify_partition_type(void)
pr_crit("Hyper-V: CONFIG_MSHV_ROOT not enabled!\n");
}
}
+
+const char *hv_result_to_string(u64 hv_status)
+{
+ switch (hv_result(hv_status)) {
+ case HV_STATUS_SUCCESS:
+ return "HV_STATUS_SUCCESS";
+ case HV_STATUS_INVALID_HYPERCALL_CODE:
+ return "HV_STATUS_INVALID_HYPERCALL_CODE";
+ case HV_STATUS_INVALID_HYPERCALL_INPUT:
+ return "HV_STATUS_INVALID_HYPERCALL_INPUT";
+ case HV_STATUS_INVALID_ALIGNMENT:
+ return "HV_STATUS_INVALID_ALIGNMENT";
+ case HV_STATUS_INVALID_PARAMETER:
+ return "HV_STATUS_INVALID_PARAMETER";
+ case HV_STATUS_ACCESS_DENIED:
+ return "HV_STATUS_ACCESS_DENIED";
+ case HV_STATUS_INVALID_PARTITION_STATE:
+ return "HV_STATUS_INVALID_PARTITION_STATE";
+ case HV_STATUS_OPERATION_DENIED:
+ return "HV_STATUS_OPERATION_DENIED";
+ case HV_STATUS_UNKNOWN_PROPERTY:
+ return "HV_STATUS_UNKNOWN_PROPERTY";
+ case HV_STATUS_PROPERTY_VALUE_OUT_OF_RANGE:
+ return "HV_STATUS_PROPERTY_VALUE_OUT_OF_RANGE";
+ case HV_STATUS_INSUFFICIENT_MEMORY:
+ return "HV_STATUS_INSUFFICIENT_MEMORY";
+ case HV_STATUS_INVALID_PARTITION_ID:
+ return "HV_STATUS_INVALID_PARTITION_ID";
+ case HV_STATUS_INVALID_VP_INDEX:
+ return "HV_STATUS_INVALID_VP_INDEX";
+ case HV_STATUS_NOT_FOUND:
+ return "HV_STATUS_NOT_FOUND";
+ case HV_STATUS_INVALID_PORT_ID:
+ return "HV_STATUS_INVALID_PORT_ID";
+ case HV_STATUS_INVALID_CONNECTION_ID:
+ return "HV_STATUS_INVALID_CONNECTION_ID";
+ case HV_STATUS_INSUFFICIENT_BUFFERS:
+ return "HV_STATUS_INSUFFICIENT_BUFFERS";
+ case HV_STATUS_NOT_ACKNOWLEDGED:
+ return "HV_STATUS_NOT_ACKNOWLEDGED";
+ case HV_STATUS_INVALID_VP_STATE:
+ return "HV_STATUS_INVALID_VP_STATE";
+ case HV_STATUS_NO_RESOURCES:
+ return "HV_STATUS_NO_RESOURCES";
+ case HV_STATUS_PROCESSOR_FEATURE_NOT_SUPPORTED:
+ return "HV_STATUS_PROCESSOR_FEATURE_NOT_SUPPORTED";
+ case HV_STATUS_INVALID_LP_INDEX:
+ return "HV_STATUS_INVALID_LP_INDEX";
+ case HV_STATUS_INVALID_REGISTER_VALUE:
+ return "HV_STATUS_INVALID_REGISTER_VALUE";
+ case HV_STATUS_OPERATION_FAILED:
+ return "HV_STATUS_OPERATION_FAILED";
+ case HV_STATUS_TIME_OUT:
+ return "HV_STATUS_TIME_OUT";
+ case HV_STATUS_CALL_PENDING:
+ return "HV_STATUS_CALL_PENDING";
+ case HV_STATUS_VTL_ALREADY_ENABLED:
+ return "HV_STATUS_VTL_ALREADY_ENABLED";
+ default:
+ return "Unknown";
+ };
+ return "Unknown";
+}
+EXPORT_SYMBOL_GPL(hv_result_to_string);
+
diff --git a/drivers/hv/hv_proc.c b/drivers/hv/hv_proc.c
index 2fae18e4f7d2..8fc30f509fa7 100644
--- a/drivers/hv/hv_proc.c
+++ b/drivers/hv/hv_proc.c
@@ -87,7 +87,8 @@ int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
page_count, 0, input_page, NULL);
local_irq_restore(flags);
if (!hv_result_success(status)) {
- pr_err("Failed to deposit pages: %lld\n", status);
+ pr_err("%s: Failed to deposit pages: %s\n", __func__,
+ hv_result_to_string(status));
ret = hv_result_to_errno(status);
goto err_free_allocations;
}
@@ -137,8 +138,9 @@ int hv_call_add_logical_proc(int node, u32 lp_index, u32 apic_id)

if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) {
if (!hv_result_success(status)) {
- pr_err("%s: cpu %u apic ID %u, %lld\n", __func__,
- lp_index, apic_id, status);
+ pr_err("%s: cpu %u apic ID %u, %s\n",
+ __func__, lp_index, apic_id,
+ hv_result_to_string(status));
ret = hv_result_to_errno(status);
}
break;
@@ -179,8 +181,9 @@ int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)

if (hv_result(status) != HV_STATUS_INSUFFICIENT_MEMORY) {
if (!hv_result_success(status)) {
- pr_err("%s: vcpu %u, lp %u, %lld\n", __func__,
- vp_index, flags, status);
+ pr_err("%s: vcpu %u, lp %u, %s\n",
+ __func__, vp_index, flags,
+ hv_result_to_string(status));
ret = hv_result_to_errno(status);
}
break;
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index b13b0cda4ac8..dc4729dba9ef 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -298,6 +298,7 @@ static inline int cpumask_to_vpset_skip(struct hv_vpset *vpset,
return __cpumask_to_vpset(vpset, cpus, func);
}

+const char *hv_result_to_string(u64 hv_status);
int hv_result_to_errno(u64 status);
void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
bool hv_is_hyperv_initialized(void);
--
2.34.1