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Date:   Tue, 9 Mar 2021 15:56:04 +0100 (CET)
From:   Christoph Lameter <cl@gentwo.de>
To:     Georgi Djakov <georgi.djakov@linaro.org>
cc:     linux-mm@kvack.org, akpm@linux-foundation.org, vbabka@suse.cz,
        penberg@kernel.org, rientjes@google.com, iamjoonsoo.kim@lge.com,
        corbet@lwn.net, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/slub: Add slub_debug option to panic on memory
 corruption
In-Reply-To: <20210309134720.29052-1-georgi.djakov@linaro.org>
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References: <20210309134720.29052-1-georgi.djakov@linaro.org>
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On Tue, 9 Mar 2021, Georgi Djakov wrote:

> Being able to stop the system immediately when a memory corruption
> is detected is crucial to finding the source of it. This is very
> useful when the memory can be inspected with kdump or other tools.

Hmmm.... ok.

>  static void restore_bytes(struct kmem_cache *s, char *message, u8 data,
>  						void *from, void *to)
>  {
> +	if (slub_debug & SLAB_CORRUPTION_PANIC)
> +		panic("slab: object overwritten\n");
>  	slab_fix(s, "Restoring 0x%p-0x%p=0x%x\n", from, to - 1, data);
>  	memset(from, data, to - from);
>  }

Why panic here? This should only be called late in the bug reporting when
an error has already been printed.