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Subject: Re: [tip: x86/cache] x86/resctrl: Fix incorrect local bandwidth when
 mba_sc is enabled
To:     Borislav Petkov <bp@alien8.de>
Cc:     linux-tip-commits@vger.kernel.org, Tony Luck <tony.luck@intel.com>,
        x86@kernel.org, linux-kernel@vger.kernel.org,
        Xiaochen Shen <xiaochen.shen@intel.com>
References: <1607063279-19437-1-git-send-email-xiaochen.shen@intel.com>
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 <20201209222328.GA20710@zn.tnic>
 <343e2fc7-6f64-d1b7-2ea1-cd422596f5be@intel.com>
 <20201210102625.GA26529@zn.tnic>
From:   Xiaochen Shen <xiaochen.shen@intel.com>
Message-ID: <f965241c-69c7-c021-47c9-ef0c028e8399@intel.com>
Date:   Fri, 11 Dec 2020 00:40:46 +0800
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Hi Boris,

On 12/10/2020 18:26, Borislav Petkov wrote:
> On Thu, Dec 10, 2020 at 12:45:11PM +0800, Xiaochen Shen wrote:
>> Thank you for clarifying this issue. It is not a 0-DAY CI issue.
> Which begs the question: this patch should be Cc: stable and should go
> in now, shouldn't it?
>
> Because then the first submission applies cleanly ontop of
> tip:x86/urgent.
>
> I mean, it is fixing only reporting but that reporting is kinda waaay
> off.
>
> Hmmm?
>

Yes. Thank you for pointing out this, we'd better add Cc: stable tag.
But we have to backport the patch for -stable trees because the code base
is changed by following upstream commits:

(1) For all stable trees: in commit abe8f12b4425 ("x86/resctrl: Remove
unused struct mbm_state::chunks_bw"), removing unused struct
mbm_state::chunks_bw changes the code base for this patch.

(2) For 4.14 and 4.19 stable trees: in commit fa7d949337cc ("x86/resctrl:
Rename and move rdt files to a separate directory"), the file
arch/x86/kernel/cpu/intel_rdt_monitor.c has been renamed and moved to
arch/x86/kernel/cpu/resctrl/monitor.c. This patch needs to be rebased.

I plan to do backporting for all -stable trees after this patch is merged
into upstream.

Thank you.

-- 
Best regards,
Xiaochen