Re: [PATCH 4/4] x86/mce: Avoid infinite loop for copy from user recovery

From: Borislav Petkov
Date: Thu Apr 08 2021 - 09:36:36 EST


On Thu, Mar 25, 2021 at 05:02:35PM -0700, Tony Luck wrote:
...
> Expected worst case is two machine checks before moving on (e.g. one user
> access with page faults disabled, then a repeat to the same addrsss with
> page faults enabled). Just in case there is some code that loops forever
> enforce a limit of 10.
>
> Signed-off-by: Tony Luck <tony.luck@xxxxxxxxx>
> ---
> arch/x86/kernel/cpu/mce/core.c | 40 ++++++++++++++++++++++++++--------
> include/linux/sched.h | 1 +
> 2 files changed, 32 insertions(+), 9 deletions(-)

What I'm still unclear on, does this new version address that
"mysterious" hang or panic which the validation team triggered or you
haven't checked yet?

Thx.

--
Regards/Gruss,
Boris.

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