From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 50DCD2620E8; Sun, 11 May 2025 23:08:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747004889; cv=none; b=cu39GmSKNr6zdyFO7/F2c1z6OxgRv4WRLDlHHxh/+K2meFZiKBCtkLm2rb3/A5IaWesOFp12qGsIsQ2EyLJy58BPCBObNVgnEZXIfUsB5YxQR4569+ij48gONN5bMAQvqsRq96o78bbDONVtGFwpVH1FIZgDgTaxzkQzSdaQuBc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747004889; c=relaxed/simple; bh=MQn24UdbbevAqrHXHYeV/oktCjUW7qO5pLk5OfEPdFo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=q1K4JHlRipIXEk4nYaZMZZ4M+IrrG7/q9XccVTdC8M/DznJf1HHUNQkuFznJcNdXfhmzzbnGm+e0Ip9olml8jMEcgi8oZjeaNzCRQHx7AdVVDWeyXIScFWZuS02p/sZQpEXa2lJENpN8M5Hb1x841CgwzITTKBgxqDvdR5GyMkA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=PzCW1yrl; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="PzCW1yrl" Received: from romank-3650.corp.microsoft.com (unknown [131.107.1.188]) by linux.microsoft.com (Postfix) with ESMTPSA id 3456B211D8B9; Sun, 11 May 2025 16:08:01 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 3456B211D8B9 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1747004881; bh=NlBiHNDCBFA2gIOS3joGMIV+HKwt3xvTaKZNTMqyrfs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PzCW1yrlgSBWFcf9ZDvqROWW59RHvobznCPyYkUchsjAvDfhkhzJGxAXr4Ut5FNta hGYnBkdDFxoWMdj8sfCOT5Mh2sQcamvpWCT/kyTAR+ttg5+dSqTXccbQwg2wUFkOh0 Z8DRv91cnRv0udrfZhUoJj42V8oOQhiRjRTWEVGo= From: Roman Kisel To: arnd@arndb.de, bp@alien8.de, catalin.marinas@arm.com, corbet@lwn.net, dave.hansen@linux.intel.com, decui@microsoft.com, haiyangz@microsoft.com, hpa@zytor.com, kys@microsoft.com, mingo@redhat.com, tglx@linutronix.de, wei.liu@kernel.org, will@kernel.org, x86@kernel.org, linux-hyperv@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arch@vger.kernel.org Cc: apais@microsoft.com, benhill@microsoft.com, bperkins@microsoft.com, sunilmut@microsoft.com Subject: [PATCH hyperv-next v2 3/4] arch: hyperv: Get/set SynIC synth.registers via paravisor Date: Sun, 11 May 2025 16:07:57 -0700 Message-ID: <20250511230758.160674-4-romank@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250511230758.160674-1-romank@linux.microsoft.com> References: <20250511230758.160674-1-romank@linux.microsoft.com> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The confidential VMBus is built on the guest talking to the paravisor only. Provide functions that allow manipulating the SynIC registers via paravisor. Signed-off-by: Roman Kisel --- arch/arm64/hyperv/mshyperv.c | 19 +++++++++++++++++++ arch/arm64/include/asm/mshyperv.h | 3 +++ arch/x86/include/asm/mshyperv.h | 3 +++ arch/x86/kernel/cpu/mshyperv.c | 28 ++++++++++++++++++++++++++++ 4 files changed, 53 insertions(+) diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c index 4fdc26ade1d7..8778b6831062 100644 --- a/arch/arm64/hyperv/mshyperv.c +++ b/arch/arm64/hyperv/mshyperv.c @@ -134,3 +134,22 @@ bool hv_is_hyperv_initialized(void) return hyperv_initialized; } EXPORT_SYMBOL_GPL(hv_is_hyperv_initialized); + +/* + * Not supported yet. + */ +u64 hv_pv_get_synic_register(unsigned int reg, int *err) +{ + *err = -ENODEV; + return !0ULL; +} +EXPORT_SYMBOL_GPL(hv_pv_get_synic_register); + +/* + * Not supported yet. + */ +int hv_pv_set_synic_register(unsigned int reg, u64 val) +{ + return -ENODEV; +} +EXPORT_SYMBOL_GPL(hv_pv_set_synic_register); diff --git a/arch/arm64/include/asm/mshyperv.h b/arch/arm64/include/asm/mshyperv.h index b721d3134ab6..bce37a58dff0 100644 --- a/arch/arm64/include/asm/mshyperv.h +++ b/arch/arm64/include/asm/mshyperv.h @@ -53,6 +53,9 @@ static inline u64 hv_get_non_nested_msr(unsigned int reg) return hv_get_msr(reg); } +u64 hv_pv_get_synic_register(unsigned int reg, int *err); +int hv_pv_set_synic_register(unsigned int reg, u64 val); + /* SMCCC hypercall parameters */ #define HV_SMCCC_FUNC_NUMBER 1 #define HV_FUNC_ID ARM_SMCCC_CALL_VAL( \ diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h index bab5ccfc60a7..0a4b01c1f094 100644 --- a/arch/x86/include/asm/mshyperv.h +++ b/arch/x86/include/asm/mshyperv.h @@ -307,6 +307,9 @@ static __always_inline u64 hv_raw_get_msr(unsigned int reg) return __rdmsr(reg); } +u64 hv_pv_get_synic_register(unsigned int reg, int *err); +int hv_pv_set_synic_register(unsigned int reg, u64 val); + #else /* CONFIG_HYPERV */ static inline void hyperv_init(void) {} static inline void hyperv_setup_mmu_ops(void) {} diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 3e2533954675..4f6e3d02f730 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -89,6 +89,34 @@ void hv_set_non_nested_msr(unsigned int reg, u64 value) } EXPORT_SYMBOL_GPL(hv_set_non_nested_msr); +/* + * Not every paravisor supports getting SynIC registers, and + * this function may fail. The caller has to make sure that this function + * runs on the CPU of interest. + */ +u64 hv_pv_get_synic_register(unsigned int reg, int *err) +{ + if (!hv_is_synic_msr(reg)) { + *err = -ENODEV; + return !0ULL; + } + return native_read_msr_safe(reg, err); +} +EXPORT_SYMBOL_GPL(hv_pv_get_synic_register); + +/* + * Not every paravisor supports setting SynIC registers, and + * this function may fail. The caller has to make sure that this function + * runs on the CPU of interest. + */ +int hv_pv_set_synic_register(unsigned int reg, u64 val) +{ + if (!hv_is_synic_msr(reg)) + return -ENODEV; + return wrmsrl_safe(reg, val); +} +EXPORT_SYMBOL_GPL(hv_pv_set_synic_register); + u64 hv_get_msr(unsigned int reg) { if (hv_nested) -- 2.43.0