[PATCH 1/2] hyperv: Move hv_current_partition_id to arch-generic code
From: Nuno Das Neves
Date: Fri Dec 06 2024 - 17:22:32 EST
From: Nuno Das Neves <nudasnev@xxxxxxxxxxxxx>
Make hv_current_partition_id available in both x86_64 and arm64.
This feature isn't specific to x86_64 and will be needed by common
code.
While at it, replace the BUG()s with WARN()s. Failing to get the id
need not crash the machine (although it is a very bad sign).
Signed-off-by: Nuno Das Neves <nudasnev@xxxxxxxxxxxxx>
---
arch/arm64/hyperv/mshyperv.c | 3 +++
arch/x86/hyperv/hv_init.c | 25 +------------------------
arch/x86/include/asm/mshyperv.h | 2 --
drivers/hv/hv_common.c | 23 +++++++++++++++++++++++
include/asm-generic/mshyperv.h | 2 ++
5 files changed, 29 insertions(+), 26 deletions(-)
diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c
index b1a4de4eee29..5050e748d266 100644
--- a/arch/arm64/hyperv/mshyperv.c
+++ b/arch/arm64/hyperv/mshyperv.c
@@ -19,6 +19,9 @@
static bool hyperv_initialized;
+u64 hv_current_partition_id = HV_PARTITION_ID_SELF;
+EXPORT_SYMBOL_GPL(hv_current_partition_id);
+
int hv_get_hypervisor_version(union hv_hypervisor_version_info *info)
{
hv_get_vpreg_128(HV_REGISTER_HYPERVISOR_VERSION,
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 95eada2994e1..950f5ccdb9d9 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -35,7 +35,7 @@
#include <clocksource/hyperv_timer.h>
#include <linux/highmem.h>
-u64 hv_current_partition_id = ~0ull;
+u64 hv_current_partition_id = HV_PARTITION_ID_SELF;
EXPORT_SYMBOL_GPL(hv_current_partition_id);
void *hv_hypercall_pg;
@@ -394,24 +394,6 @@ static void __init hv_stimer_setup_percpu_clockev(void)
old_setup_percpu_clockev();
}
-static void __init hv_get_partition_id(void)
-{
- struct hv_get_partition_id *output_page;
- u64 status;
- unsigned long flags;
-
- local_irq_save(flags);
- output_page = *this_cpu_ptr(hyperv_pcpu_output_arg);
- status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page);
- if (!hv_result_success(status)) {
- /* No point in proceeding if this failed */
- pr_err("Failed to get partition ID: %lld\n", status);
- BUG();
- }
- hv_current_partition_id = output_page->partition_id;
- local_irq_restore(flags);
-}
-
#if IS_ENABLED(CONFIG_HYPERV_VTL_MODE)
static u8 __init get_vtl(void)
{
@@ -606,11 +588,6 @@ void __init hyperv_init(void)
register_syscore_ops(&hv_syscore_ops);
- if (cpuid_ebx(HYPERV_CPUID_FEATURES) & HV_ACCESS_PARTITION_ID)
- hv_get_partition_id();
-
- BUG_ON(hv_root_partition && hv_current_partition_id == ~0ull);
-
#ifdef CONFIG_PCI_MSI
/*
* If we're running as root, we want to create our own PCI MSI domain.
diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 5f0bc6a6d025..9eeca2a6d047 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -44,8 +44,6 @@ extern bool hyperv_paravisor_present;
extern void *hv_hypercall_pg;
-extern u64 hv_current_partition_id;
-
extern union hv_ghcb * __percpu *hv_ghcb_pg;
bool hv_isolation_type_snp(void);
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 7a35c82976e0..819bcfd2b149 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -278,11 +278,34 @@ static void hv_kmsg_dump_register(void)
}
}
+static void __init hv_get_partition_id(void)
+{
+ struct hv_get_partition_id *output_page;
+ u64 status;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ output_page = *this_cpu_ptr(hyperv_pcpu_output_arg);
+ status = hv_do_hypercall(HVCALL_GET_PARTITION_ID, NULL, output_page);
+ if (!hv_result_success(status)) {
+ local_irq_restore(flags);
+ WARN(true, "Failed to get partition ID: %lld\n", status);
+ return;
+ }
+ hv_current_partition_id = output_page->partition_id;
+ local_irq_restore(flags);
+}
+
int __init hv_common_init(void)
{
int i;
union hv_hypervisor_version_info version;
+ if (ms_hyperv.priv_high & HV_ACCESS_PARTITION_ID)
+ hv_get_partition_id();
+
+ WARN_ON(hv_root_partition && hv_current_partition_id == HV_PARTITION_ID_SELF);
+
/* Get information about the Hyper-V host version */
if (!hv_get_hypervisor_version(&version))
pr_info("Hyper-V: Host Build %d.%d.%d.%d-%d-%d\n",
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index 8fe7aaab2599..8c4ff6e9aae7 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -60,6 +60,8 @@ struct ms_hyperv_info {
extern struct ms_hyperv_info ms_hyperv;
extern bool hv_nested;
+extern u64 hv_current_partition_id;
+
extern void * __percpu *hyperv_pcpu_input_arg;
extern void * __percpu *hyperv_pcpu_output_arg;
--
2.34.1