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Date:   Mon, 31 Jul 2023 20:21:32 +0100
From:   Lorenzo Stoakes <lstoakes@gmail.com>
To:     David Hildenbrand <david@redhat.com>
Cc:     Baoquan He <bhe@redhat.com>, Jiri Olsa <olsajiri@gmail.com>,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        linux-fsdevel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        Uladzislau Rezki <urezki@gmail.com>,
        Matthew Wilcox <willy@infradead.org>,
        Liu Shixin <liushixin2@huawei.com>,
        Jens Axboe <axboe@kernel.dk>,
        Alexander Viro <viro@zeniv.linux.org.uk>
Subject: Re: [PATCH v8 1/4] fs/proc/kcore: avoid bounce buffer for ktext data
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On Mon, Jul 24, 2023 at 08:23:55AM +0200, David Hildenbrand wrote:
> Hi,
>
> >
> > I met this too when I executed below command to trigger a kcore reading.
> > I wanted to do a simple testing during system running and got this.
> >
> >    makedumpfile --mem-usage /proc/kcore
> >
> > Later I tried your above objdump testing, it corrupted system too.
> >
>
> What do you mean with "corrupted system too" --  did it not only fail to
> dump the system, but also actually harmed the system?
>
> @Lorenzo do you plan on reproduce + fix, or should we consider reverting
> that change?
>
> --
> Cheers,
>
> David / dhildenb
>

Apologies I mised this, I have been very busy lately not least with book :)

Concerning, I will take a look as I get a chance. I think the whole series
would have to be reverted which would be... depressing... as other patches
in series eliminates the bounce buffer altogether.