linux-kernel - MSR access API uses in KVM x86

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-next>] [day] [month] [year] [list]

Message-ID: <a82f4722-478f-4972-a072-80cd13666137@zytor.com>
Date: Mon, 21 Apr 2025 10:21:30 -0700
From: Xin Li <xin@...or.com>
To: Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc: "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "kvm@...r.kernel.org" <kvm@...r.kernel.org>,
        "H. Peter Anvin"
 <hpa@...or.com>, Ingo Molnar <mingo@...hat.com>
Subject: MSR access API uses in KVM x86

It looks to me that MSR access API uses in KVM x86 are NOT consistent;
sometimes {wr,rd}msrl() are used and sometimes native_{wr,rd}msrl() are
used.

Was there a reason that how a generic or native MSR API was chosen?

In my opinion KVM should use the native MSR APIs, which can streamline
operations and potentially improve performance by avoiding the overhead
associated with generic MSR API indirect calls when CONFIG_XEN_PV=y.

No?

Thanks!
     Xin