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Date:   Wed, 21 Jun 2023 09:38:35 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Waiman Long <longman@redhat.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Josh Poimboeuf <jpoimboe@kernel.org>,
        Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        Jacob Pan <jacob.jun.pan@linux.intel.com>,
        Len Brown <lenb@kernel.org>, linux-kernel@vger.kernel.org,
        x86@kernel.org, linux-pm@vger.kernel.org,
        Robin Jarry <rjarry@redhat.com>, Joe Mario <jmario@redhat.com>
Subject: Re: [PATCH v2 3/5] intel_idle: Sync up the SPEC_CTRL MSR value to
 x86_spec_ctrl_current
Message-ID: <20230621073835.GD2046280@hirez.programming.kicks-ass.net>
References: <20230620140625.1001886-1-longman@redhat.com>
 <20230620140625.1001886-4-longman@redhat.com>
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On Tue, Jun 20, 2023 at 10:06:23AM -0400, Waiman Long wrote:
> When intel_idle_ibrs() is called, it modifies the SPEC_CTRL MSR to 0
> in order disable IBRS. However, the new MSR value isn't reflected in
> x86_spec_ctrl_current. That will cause the new spec_ctrl_msrs debugfs
> file to show incorrect result. Fix that by updating x86_spec_ctrl_current
> percpu value to always match the content of the SPEC_CTRL MSR.

What debugfs file?