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Date:   Thu, 2 Apr 2020 16:16:25 -0700 (PDT)
From:   "Kenneth R. Crudup" <kenny@panix.com>
Reply-To: "Kenneth R. Crudup" <kenny@panix.com>
To:     Steven Rostedt <rostedt@goodmis.org>
cc:     Nadav Amit <namit@vmware.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Sean Christopherson <sean.j.christopherson@intel.com>,
        x86 <x86@kernel.org>, Paolo Bonzini <pbonzini@redhat.com>,
        Fenghua Yu <fenghua.yu@intel.com>,
        Xiaoyao Li <xiaoyao.li@intel.com>,
        Thomas Hellstrom <thellstrom@vmware.com>,
        Tony Luck <tony.luck@intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Jessica Yu <jeyu@kernel.org>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>, kvm <kvm@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Doug Covelli <dcovelli@vmware.com>
Subject: Re: [PATCH 3/3] KVM: VMX: Extend VMX's #AC interceptor to handle
 split lock #AC in guest
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On Thu, 2 Apr 2020, Steven Rostedt wrote:

> If we go the approach of not letting VM modules load if it doesn't have the
> sld_safe flag set, how is this different than a VM module not loading due
> to kabi breakage?

Why not a compromise: if such a module is attempted to be loaded, print up
a message saying something akin to "turn the parameter 'split_lock_detect'
off" as we reject loading it- and if we see that we've booted with it off
just splat a WARN_ON() if someone tries to load such modules?

	-Kenny

-- 
Kenneth R. Crudup  Sr. SW Engineer, Scott County Consulting, Silicon Valley