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Date:   Fri, 18 Mar 2022 10:10:54 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     Christoph Hellwig <hch@lst.de>, axboe@kernel.dk,
        jaegeuk@kernel.org, chao@kernel.org, ulf.hansson@linaro.org,
        Adrian Hunter <adrian.hunter@intel.com>,
        Daeho Jeong <daehojeong@google.com>,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mmc@vger.kernel.org
Subject: Re: security issue: data exposure when using block layer secure
 erase
Message-ID: <20220318091054.GA31758@lst.de>
References: <20220316093740.GA7714@lst.de> <YjIm6f6pSX1CKeqb@gmail.com>
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On Wed, Mar 16, 2022 at 06:05:29PM +0000, Eric Biggers wrote:
> __blkdev_issue_discard() can break up the region into multiple bios, but I don't
> see where it actually skips parts of the region.  Can you explain more
> specifically where the problem is?

You're right.  We used to skip misaligned parts, but that was actually
fixed two years ago.