Re: [PATCH hyperv-next v3 04/15] arch/x86: mshyperv: Trap on access for some synthetic MSRs

To: Roman Kisel <romank@xxxxxxxxxxxxxxxxxxx>, arnd@xxxxxxxx, bp@xxxxxxxxx, corbet@xxxxxxx, dave.hansen@xxxxxxxxxxxxxxx, decui@xxxxxxxxxxxxx, haiyangz@xxxxxxxxxxxxx, hpa@xxxxxxxxx, kys@xxxxxxxxxxxxx, mingo@xxxxxxxxxx, mhklinux@xxxxxxxxxxx, tglx@xxxxxxxxxxxxx, wei.liu@xxxxxxxxxx, linux-arch@xxxxxxxxxxxxxxx, linux-doc@xxxxxxxxxxxxxxx, linux-hyperv@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx, x86@xxxxxxxxxx
Subject: Re: [PATCH hyperv-next v3 04/15] arch/x86: mshyperv: Trap on access for some synthetic MSRs
From: ALOK TIWARI <alok.a.tiwari@xxxxxxxxxx>
Date: Wed, 4 Jun 2025 19:08:33 +0530
Cc: apais@xxxxxxxxxxxxx, benhill@xxxxxxxxxxxxx, bperkins@xxxxxxxxxxxxx, sunilmut@xxxxxxxxxxxxx
In-reply-to: <20250604004341.7194-5-romank@linux.microsoft.com>
References: <20250604004341.7194-1-romank@linux.microsoft.com> <20250604004341.7194-5-romank@linux.microsoft.com>
User-agent: Mozilla Thunderbird



On 04-06-2025 06:13, Roman Kisel wrote:

+			/*
+			 * Write proxy bit in the case of non-confidential VMBus.
+			 * Using wrmsl instruction so the following goes to the paravisor.


wrmsl -> wrmsrl

+			 */
+			u32 proxy = vmbus_is_confidential() ? 0 : 1;
+
+			value |= (proxy << 20);
+			native_wrmsrl(reg, value);
+		}
  	} else {



Thanks,
Alok

References:
- [PATCH hyperv-next v3 00/15] Confidential VMBus
  - From: Roman Kisel
- [PATCH hyperv-next v3 04/15] arch/x86: mshyperv: Trap on access for some synthetic MSRs
  - From: Roman Kisel