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Message-ID: <86fd0ccb-f460-651f-8048-1026d905a2d6@redhat.com>
Date:   Mon, 24 Jul 2023 08:23:55 +0200
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Subject: Re: [PATCH v8 1/4] fs/proc/kcore: avoid bounce buffer for ktext data
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To:     Baoquan He <bhe@redhat.com>, Jiri Olsa <olsajiri@gmail.com>
Cc:     Lorenzo Stoakes <lstoakes@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>
References: <cover.1679566220.git.lstoakes@gmail.com>
 <fd39b0bfa7edc76d360def7d034baaee71d90158.1679566220.git.lstoakes@gmail.com>
 <ZHc2fm+9daF6cgCE@krava> <ZLqMtcPXAA8g/4JI@MiWiFi-R3L-srv>
From:   David Hildenbrand <david@redhat.com>
Organization: Red Hat
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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