Re: kernel-side thread stack swapping

From: Mateusz Guzik <mjguzik_at_gmail.com>
Date: Fri, 02 Sep 2022 14:11:40 UTC
On 9/2/22, Konstantin Belousov <kostikbel@gmail.com> wrote:
> On Fri, Sep 02, 2022 at 02:05:37PM +0200, Mateusz Guzik wrote:
>> Is this really of practical use today?
>>
>> I have a WIP patch which needs to temporarily store something on the
>> stack and should things go wrong enough it will be accessed by UMA,
>> which can't handle the fault nor decide to skip the access.
>>
>> I can add something like td_pinstack or whatever to keep it around,
>> but perhaps the entire machinery can be just whacked?
> p_hold already does that.
>

I only need to protect the one stack and more importantly don't want
to take the proc lock to bump p_hold (nor convert it to atomics), it's
all thread-local so to speak.

-- 
Mateusz Guzik <mjguzik gmail.com>