[PATCH v2 13/15] mshv_vtl: Add remaining support for arm64

From: Naman Jain <namjain@linux.microsoft.com>
To: "K . Y . Srinivasan" <kys@microsoft.com>,
	Haiyang Zhang <haiyangz@microsoft.com>,
	Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
	Long Li <longli@microsoft.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>, Thomas Gleixner <tglx@kernel.org>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	x86@kernel.org, "H . Peter Anvin" <hpa@zytor.com>,
	Arnd Bergmann <arnd@arndb.de>, Paul Walmsley <pjw@kernel.org>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Alexandre Ghiti <alex@ghiti.fr>,
	Michael Kelley <mhklinux@outlook.com>
Cc: Marc Zyngier <maz@kernel.org>,
	Timothy Hayes <timothy.hayes@arm.com>,
	Lorenzo Pieralisi <lpieralisi@kernel.org>,
	Sascha Bischoff <sascha.bischoff@arm.com>,
	mrigendrachaubey <mrigendra.chaubey@gmail.com>,
	Naman Jain <namjain@linux.microsoft.com>,
	linux-hyperv@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
	linux-riscv@lists.infradead.org, vdso@mailbox.org,
	ssengar@linux.microsoft.com
Subject: [PATCH v2 13/15] mshv_vtl: Add remaining support for arm64
Date: Thu, 23 Apr 2026 12:42:03 +0000	[thread overview]
Message-ID: <20260423124206.2410879-14-namjain@linux.microsoft.com> (raw)
In-Reply-To: <20260423124206.2410879-1-namjain@linux.microsoft.com>

Add necessary support to make MSHV_VTL work for arm64 architecture.
* Add stub implementation for mshv_vtl_return_call_init() as it's not
  required for arm64
* Handle hugepage functions by config checks, as it's x86 specific
* fpu/legacy.h header inclusion was required when x86 assembly code
  was present here, it got left when the code was moved to arch files.
  Remove it now (unrelated to arm64)

Signed-off-by: Roman Kisel <romank@linux.microsoft.com>
Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
---
 arch/arm64/include/asm/mshyperv.h | 2 ++
 drivers/hv/mshv_vtl_main.c        | 4 ++--
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/include/asm/mshyperv.h b/arch/arm64/include/asm/mshyperv.h
index 9eb0e5999f29..6f668ec68b2f 100644
--- a/arch/arm64/include/asm/mshyperv.h
+++ b/arch/arm64/include/asm/mshyperv.h
@@ -82,6 +82,8 @@ static inline int hv_vtl_get_set_reg(struct hv_register_assoc *regs, bool set, b
 	return 1;
 }
 
+/* Stubbed for arm64 */
+static inline int mshv_vtl_return_call_init(void) { return 0; }
 #endif
 
 #include <asm-generic/mshyperv.h>
diff --git a/drivers/hv/mshv_vtl_main.c b/drivers/hv/mshv_vtl_main.c
index be498c9234fd..d5308956dfb6 100644
--- a/drivers/hv/mshv_vtl_main.c
+++ b/drivers/hv/mshv_vtl_main.c
@@ -23,8 +23,6 @@
 #include <trace/events/ipi.h>
 #include <uapi/linux/mshv.h>
 #include <hyperv/hvhdk.h>
-
-#include "../../kernel/fpu/legacy.h"
 #include "mshv.h"
 #include "mshv_vtl.h"
 #include "hyperv_vmbus.h"
@@ -1077,10 +1075,12 @@ static vm_fault_t mshv_vtl_low_huge_fault(struct vm_fault *vmf, unsigned int ord
 			ret = vmf_insert_pfn_pmd(vmf, pfn, vmf->flags & FAULT_FLAG_WRITE);
 		return ret;
 
+#if defined(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD)
 	case PUD_ORDER:
 		if (can_fault(vmf, PUD_SIZE, &pfn))
 			ret = vmf_insert_pfn_pud(vmf, pfn, vmf->flags & FAULT_FLAG_WRITE);
 		return ret;
+#endif
 
 	default:
 		return VM_FAULT_SIGBUS;
-- 
2.43.0


