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Date:   Tue, 24 May 2022 11:41:19 -0700
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Subject: Re: [PATCH] x86/resctrl: Fix to restore to original value when
 re-enabling hardware prefetch register
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To:     Kohei Tarumizu <tarumizu.kohei@fujitsu.com>, fenghua.yu@intel.com,
        reinette.chatre@intel.com, tglx@linutronix.de, mingo@redhat.com,
        bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org,
        hpa@zytor.com, linux-kernel@vger.kernel.org
References: <20220518045517.2066518-1-tarumizu.kohei@fujitsu.com>
From:   Dave Hansen <dave.hansen@intel.com>
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On 5/17/22 21:55, Kohei Tarumizu wrote:
> The current pseudo_lock.c code overwrites the value of the
> MSR_MISC_FEATURE_CONTROL to 0 even if the original value is not 0.
> Therefore, modify it to save and restore the original values.
> 
> Fixes: 018961ae5579 ("x86/intel_rdt: Pseudo-lock region creation/removal core")
> Fixes: 443810fe6160 ("x86/intel_rdt: Create debugfs files for pseudo-locking testing")
> Fixes: 8a2fc0e1bc0c ("x86/intel_rdt: More precise L2 hit/miss measurements")
> Signed-off-by: Kohei Tarumizu <tarumizu.kohei@fujitsu.com>

Those commits are pretty old.  Is there any reason this is not stable@
material?