Re: [PATCH -next v5 2/3] x86/mce: set MCE_IN_KERNEL_COPYIN for DEFAULT_MCE_SAFE exception

[Borislav Petkov]

On Sun, Feb 18, 2024 at 06:08:14PM +0800, Tong Tiangen wrote:
> 1. The copy_mc_to_kernel() is used in the coredump, KSM, and COW
> scenarios, in these scenarios, the src mem stores the user data and the
> kernel use kernel address to access the src mem(using kmap()).
> 
> 2. the src mem of copy_mc_to_user() is currently only used by the DAX:

You mean just because it currently is used somewhere which probably is
ok - no clue what DAX does - and even if the source address is still
*kernel* memory and even at the danger that someone else might use it in
the future and think the handling on a potential #MC is ok, you're still
arguing that this is the right thing to do perhaps because it fits your
use case?!

Sorry Tiangen, not gonna happen.

-- 
Regards/Gruss,
    Boris.

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