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Date: Tue, 20 Feb 2024 00:50:55 +0100
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Subject: Re: regression/bisected commit
 773688a6cb24b0b3c2ba40354d883348a2befa38 make my system completely unusable
 under high load
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Marco Elver <elver@google.com>,
 Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>,
 Andrey Konovalov <andreyknvl@gmail.com>, glider@google.com,
 dvyukov@google.com, eugenis@google.com, Oscar Salvador <osalvador@suse.de>,
 Linux List Kernel Mailing <linux-kernel@vger.kernel.org>,
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From: Vlastimil Babka <vbabka@suse.cz>
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On 2/20/24 00:28, Andrew Morton wrote:
> On Mon, 19 Feb 2024 11:09:23 +0100 Vlastimil Babka <vbabka@suse.cz> wrote:
> 
>> On 2/19/24 10:52, Marco Elver wrote:
>>> On Mon, 19 Feb 2024 at 10:48, Mikhail Gavrilov
>>> <mikhail.v.gavrilov@gmail.com> wrote:
>>>>
>>>> On Sat, Feb 3, 2024 at 1:14 AM Mikhail Gavrilov
>>>> <mikhail.v.gavrilov@gmail.com> wrote:
>>>>>
>>>>> You are right.
>>>>> Thanks for digging into it!
>>>>>
>>>>
>>>> This [2] revert is still not merged at least I checked on 4f5e5092fdbf.
>>>> Is there any plan to merge it or find another approach?
>>>>
>>>> [2] https://lore.kernel.org/all/20240118110216.2539519-2-elver@google.com/
>>>
>>> I think it's already in -mm and -next. It just takes time, which is a
>>> good thing, after all we want to let -next testing confirm nothing is
>>> wrong with it.
>>>
>>> Andrew, is this planned for the next merge window or as a "hot fix"
>>> for the current rc? Given it has the right "Fixes" tags it will make
>>> it to stable kernels eventually, but I also think that the previous
>>> "slow" version is almost unusable on big systems, so it may be
>>> worthwhile considering the current rc.
>>
>> Yeah it would be best to fix in 6.8 to prevent regressions.
>>
> 
> I'm all confused.
> 
> 4434a56ec209 ("stackdepot: make fast paths lock-less again") was
> mainlined for v6.8-rc3.

Uh sorry, I just trusted the info that it's not merged and didn't verify
it myself. Yeah, I can see it is there.

> That patch Fixed: 108be8def46e ("lib/stackdepot: allow users to evict
> stack traces") which was mainlined for v6.8-rc1, so 4434a56ec209 did
> not need a cc:stable?

That's right.