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In-Reply-To: <ce149f9bdcbc80a92549b54da67eafb27f846b7b.1676063693.git.andreyknvl@google.com>
From:   Alexander Potapenko <glider@google.com>
Date:   Mon, 13 Feb 2023 12:02:39 +0100
Message-ID: <CAG_fn=WJC8wj64NTGMuHzsiTs1hfXxFT_Z1zC6+Fh5cOEKLYNA@mail.gmail.com>
Subject: Re: [PATCH v2 12/18] lib/stacktrace: drop impossible WARN_ON for depot_init_pool
To:     andrey.konovalov@linux.dev
Cc:     Marco Elver <elver@google.com>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        Vlastimil Babka <vbabka@suse.cz>, kasan-dev@googlegroups.com,
        Evgenii Stepanov <eugenis@google.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Andrey Konovalov <andreyknvl@google.com>
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On Fri, Feb 10, 2023 at 10:18 PM <andrey.konovalov@linux.dev> wrote:
>
> From: Andrey Konovalov <andreyknvl@google.com>
>
> depot_init_pool has two call sites:
>
> 1. In depot_alloc_stack with a potentially NULL prealloc.
> 2. In __stack_depot_save with a non-NULL prealloc.
>
> At the same time depot_init_pool can only return false when prealloc is
> NULL.
>
> As the second call site makes sure that prealloc is not NULL, the WARN_ON
> there can never trigger. Thus, drop the WARN_ON and also move the prealloc
> check from depot_init_pool to its first call site.
>
> Also change the return type of depot_init_pool to void as it now always
> returns true.
>
> Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>