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Date:   Sun, 1 Aug 2021 20:26:04 -0700 (PDT)
From:   David Rientjes <rientjes@google.com>
To:     Vlastimil Babka <vbabka@suse.cz>
cc:     Vijayanand Jitta <vjitta@codeaurora.org>, cl@linux.com,
        penberg@kernel.org, iamjoonsoo.kim@lge.com,
        akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, vinmenon@codeaurora.org
Subject: Re: [PATCH] mm: slub: Fix slub_debug disablement for list of slabs
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On Tue, 27 Jul 2021, Vlastimil Babka wrote:

> From 81a225fe31e53701902bb4caa9ab1524eb044cbc Mon Sep 17 00:00:00 2001
> From: Vlastimil Babka <vbabka@suse.cz>
> Date: Tue, 13 Jul 2021 17:15:50 +0530
> Subject: [PATCH] mm: slub: fix slub_debug disabling for list of slabs
> 
> Vijayanand Jitta reports:
> 
>   Consider the scenario where CONFIG_SLUB_DEBUG_ON is set
>   and we would want to disable slub_debug for few slabs.
>   Using boot parameter with slub_debug=-,slab_name syntax
>   doesn't work as expected i.e; only disabling debugging for
>   the specified list of slabs. Instead it disables debugging
>   for all slabs, which is wrong.
> 
> This patch fixes it by delaying the moment when the global slub_debug flags
> variable is updated. In case a "slub_debug=-,slab_name" has been passed, the
> global flags remain as initialized (depending on CONFIG_SLUB_DEBUG_ON enabled
> or disabled) and are not simply reset to 0.
> 
> Reported-by: Vijayanand Jitta <vjitta@codeaurora.org>
> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
> Reviewed-by: Vijayanand Jitta <vjitta@codeaurora.org>

Acked-by: David Rientjes <rientjes@google.com>

Looks better, thanks!