linux-kernel - [PATCH hyperv-next v5 04/11] Drivers: hv: Provide arch-neutral implementation of get

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250307220304.247725-5-romank@linux.microsoft.com>
Date: Fri,  7 Mar 2025 14:02:56 -0800
From: Roman Kisel <romank@...ux.microsoft.com>
To: arnd@...db.de,
	bhelgaas@...gle.com,
	bp@...en8.de,
	catalin.marinas@....com,
	conor+dt@...nel.org,
	dave.hansen@...ux.intel.com,
	decui@...rosoft.com,
	haiyangz@...rosoft.com,
	hpa@...or.com,
	joey.gouly@....com,
	krzk+dt@...nel.org,
	kw@...ux.com,
	kys@...rosoft.com,
	lenb@...nel.org,
	lpieralisi@...nel.org,
	manivannan.sadhasivam@...aro.org,
	mark.rutland@....com,
	maz@...nel.org,
	mingo@...hat.com,
	oliver.upton@...ux.dev,
	rafael@...nel.org,
	robh@...nel.org,
	ssengar@...ux.microsoft.com,
	sudeep.holla@....com,
	suzuki.poulose@....com,
	tglx@...utronix.de,
	wei.liu@...nel.org,
	will@...nel.org,
	yuzenghui@...wei.com,
	devicetree@...r.kernel.org,
	kvmarm@...ts.linux.dev,
	linux-acpi@...r.kernel.org,
	linux-arch@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org,
	linux-hyperv@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-pci@...r.kernel.org,
	x86@...nel.org
Cc: apais@...rosoft.com,
	benhill@...rosoft.com,
	bperkins@...rosoft.com,
	sunilmut@...rosoft.com
Subject: [PATCH hyperv-next v5 04/11] Drivers: hv: Provide arch-neutral implementation of get_vtl()

To run in the VTL mode, Hyper-V drivers have to know what
VTL the system boots in, and the arm64/hyperv code does not
have the means to compute that.

Refactor the code to hoist the function that detects VTL,
make it arch-neutral to be able to employ it to get the VTL
on arm64.

Signed-off-by: Roman Kisel <romank@...ux.microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@...look.com>
---
 arch/x86/hyperv/hv_init.c      | 34 ----------------------------------
 drivers/hv/hv_common.c         | 31 +++++++++++++++++++++++++++++++
 include/asm-generic/mshyperv.h |  6 ++++++
 include/hyperv/hvgdk_mini.h    |  2 +-
 4 files changed, 38 insertions(+), 35 deletions(-)

diff --git a/arch/x86/hyperv/hv_init.c b/arch/x86/hyperv/hv_init.c
index 9be1446f5bd3..e204cb9d41af 100644
--- a/arch/x86/hyperv/hv_init.c
+++ b/arch/x86/hyperv/hv_init.c
@@ -390,40 +390,6 @@ static void __init hv_stimer_setup_percpu_clockev(void)
 		old_setup_percpu_clockev();
 }
 
-#if IS_ENABLED(CONFIG_HYPERV_VTL_MODE)
-static u8 __init get_vtl(void)
-{
-	u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_REGISTERS;
-	struct hv_input_get_vp_registers *input;
-	struct hv_output_get_vp_registers *output;
-	unsigned long flags;
-	u64 ret;
-
-	local_irq_save(flags);
-	input = *this_cpu_ptr(hyperv_pcpu_input_arg);
-	output = *this_cpu_ptr(hyperv_pcpu_output_arg);
-
-	memset(input, 0, struct_size(input, names, 1));
-	input->partition_id = HV_PARTITION_ID_SELF;
-	input->vp_index = HV_VP_INDEX_SELF;
-	input->input_vtl.as_uint8 = 0;
-	input->names[0] = HV_REGISTER_VSM_VP_STATUS;
-
-	ret = hv_do_hypercall(control, input, output);
-	if (hv_result_success(ret)) {
-		ret = output->values[0].reg8 & HV_X64_VTL_MASK;
-	} else {
-		pr_err("Failed to get VTL(error: %lld) exiting...\n", ret);
-		BUG();
-	}
-
-	local_irq_restore(flags);
-	return ret;
-}
-#else
-static inline u8 get_vtl(void) { return 0; }
-#endif
-
 /*
  * This function is to be invoked early in the boot sequence after the
  * hypervisor has been detected.
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index ee3083937b4f..10983e854a4d 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -304,6 +304,37 @@ void __init hv_get_partition_id(void)
 		pr_err("Hyper-V: failed to get partition ID: %#x\n",
 		       hv_result(status));
 }
+#if IS_ENABLED(CONFIG_HYPERV_VTL_MODE)
+u8 __init get_vtl(void)
+{
+	u64 control = HV_HYPERCALL_REP_COMP_1 | HVCALL_GET_VP_REGISTERS;
+	struct hv_input_get_vp_registers *input;
+	struct hv_output_get_vp_registers *output;
+	unsigned long flags;
+	u64 ret;
+
+	local_irq_save(flags);
+	input = *this_cpu_ptr(hyperv_pcpu_input_arg);
+	output = *this_cpu_ptr(hyperv_pcpu_output_arg);
+
+	memset(input, 0, struct_size(input, names, 1));
+	input->partition_id = HV_PARTITION_ID_SELF;
+	input->vp_index = HV_VP_INDEX_SELF;
+	input->input_vtl.as_uint8 = 0;
+	input->names[0] = HV_REGISTER_VSM_VP_STATUS;
+
+	ret = hv_do_hypercall(control, input, output);
+	if (hv_result_success(ret)) {
+		ret = output->values[0].reg8 & HV_VTL_MASK;
+	} else {
+		pr_err("Failed to get VTL(error: %lld) exiting...\n", ret);
+		BUG();
+	}
+
+	local_irq_restore(flags);
+	return ret;
+}
+#endif
 
 int __init hv_common_init(void)
 {
diff --git a/include/asm-generic/mshyperv.h b/include/asm-generic/mshyperv.h
index 7adc10a4fa3e..bf897c528976 100644
--- a/include/asm-generic/mshyperv.h
+++ b/include/asm-generic/mshyperv.h
@@ -320,4 +320,10 @@ static inline enum hv_isolation_type hv_get_isolation_type(void)
 }
 #endif /* CONFIG_HYPERV */
 
+#if IS_ENABLED(CONFIG_HYPERV_VTL_MODE)
+u8 __init get_vtl(void);
+#else
+static inline u8 get_vtl(void) { return 0; }
+#endif
+
 #endif
diff --git a/include/hyperv/hvgdk_mini.h b/include/hyperv/hvgdk_mini.h
index 58895883f636..98aa64e8844c 100644
--- a/include/hyperv/hvgdk_mini.h
+++ b/include/hyperv/hvgdk_mini.h
@@ -1202,7 +1202,7 @@ struct hv_send_ipi {	 /* HV_INPUT_SEND_SYNTHETIC_CLUSTER_IPI */
 	u64 cpu_mask;
 } __packed;
 
-#define	HV_X64_VTL_MASK			GENMASK(3, 0)
+#define	HV_VTL_MASK			GENMASK(3, 0)
 
 /* Hyper-V memory host visibility */
 enum hv_mem_host_visibility {
-- 
2.43.0