On 5/2/2023 12:30 PM, Zhi Wang wrote:
On Mon, 1 May 2023 04:57:13 -0400
Tianyu Lan <ltykernel@xxxxxxxxx> wrote:
From: Tianyu Lan <tiala@xxxxxxxxxxxxx>
sev-snp guest provides vtl(Virtual Trust Level) and
get it from hyperv hvcall via HVCALL_GET_VP_REGISTERS.
Set target vtl in the VMBus init message.
Signed-off-by: Tianyu Lan <tiala@xxxxxxxxxxxxx>
---
Change since RFC v4:
* Use struct_size to calculate array size.
* Fix some coding style
Change since RFC v3:
* Use the standard helper functions to check hypercall result
* Fix coding style
Change since RFC v2:
* Rename get_current_vtl() to get_vtl()
* Fix some coding style issues
---
arch/x86/hyperv/hv_init.c | 36 ++++++++++++++++++++++++++++++
arch/x86/include/asm/hyperv-tlfs.h | 7 ++++++
drivers/hv/connection.c | 1 +
include/asm-generic/mshyperv.h | 1 +
include/linux/hyperv.h | 4 ++--
5 files changed, 47 insertions(+), 2 deletions(-)
diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 9f3e2d71d015..331b855314b7 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -384,6 +384,40 @@ static void __init hv_get_partition_id(void)
local_irq_restore(flags);
}
+static u8 __init get_vtl(void)
+{
+ u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_REGISTERS;
+ struct hv_get_vp_registers_input *input;
+ struct hv_get_vp_registers_output *output;
+ u64 vtl = 0;
+ u64 ret;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ input = *this_cpu_ptr(hyperv_pcpu_input_arg);
+ output = (struct hv_get_vp_registers_output *)input;
===
+ if (!input) {
+ local_irq_restore(flags);
+ goto done;
+ }
+
===
Is this really necessary?
drivers/hv/hv_common.c:
hyperv_pcpu_input_arg = alloc_percpu(void *);
BUG_ON(!hyperv_pcpu_input_arg);
Hi Zhi:
The hyperv_pcpu_input_arg is a point to address of input arg
pages and these pages are allocated in the hv_common_cpu_init(). If
it failed to allocate these pages, the value pointed by
hyperv_pcpu_input_arg will be NULL.
