linux-kernel - Re: [PATCH -next v4 2/3] x86/mce: rename MCE_IN_KERNEL_COPYIN to MCE_IN_KERNEL_COPY

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Message-ID: <3009aadd-69d6-c797-20b4-95cf926b6dd9@huawei.com>
Date: Thu, 1 Feb 2024 19:37:25 +0800
From: Tong Tiangen <tongtiangen@...wei.com>
To: Borislav Petkov <bp@...en8.de>
CC: Thomas Gleixner <tglx@...utronix.de>, Ingo Molnar <mingo@...hat.com>,
	<wangkefeng.wang@...wei.com>, Dave Hansen <dave.hansen@...ux.intel.com>,
	<x86@...nel.org>, "H. Peter Anvin" <hpa@...or.com>, Tony Luck
	<tony.luck@...el.com>, Andy Lutomirski <luto@...nel.org>, Peter Zijlstra
	<peterz@...radead.org>, Andrew Morton <akpm@...ux-foundation.org>, Naoya
 Horiguchi <naoya.horiguchi@....com>, <linux-kernel@...r.kernel.org>,
	<linux-edac@...r.kernel.org>, <linux-mm@...ck.org>, Guohanjun
	<guohanjun@...wei.com>
Subject: Re: [PATCH -next v4 2/3] x86/mce: rename MCE_IN_KERNEL_COPYIN to
 MCE_IN_KERNEL_COPY_MC



在 2024/1/31 15:02, Borislav Petkov 写道:
> On Thu, Jan 11, 2024 at 09:55:47PM +0800, Tong Tiangen wrote:
>> Currently, there are some kernel memory copy scenarios is also mc safe
>> which use copy_mc_to_kernel() or copy_mc_user_highpage().
> 
> Both of those end up in copy_mc_enhanced_fast_string() which does
> EX_TYPE_DEFAULT_MCE_SAFE.

OK, how about this commit msg change? :)

Currently, there are some kernel memory copy scenarios is also mc safe
which use copy_mc_to_kernel() or copy_mc_user_highpage(), **both of 
those end up in copy_mc_enhanced_fast_string() or copy_mc_fragile() 
which does EX_TYPE_DEFAULT_MCE_SAFE.**

In these scenarios, posion pages need to be isolated too. Therefore, a
macro similar to MCE_IN_KERNEL_COPYIN is required. For this reason, we
can rename MCE_IN_KERNEL_COPYIN to MCE_IN_KERNEL_COPY_MC, the new macro
can be applied to both user-to-kernel mc safe copy and kernel-to-kernel
mc safe copy.

Thanks.
Tong.

>