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Subject: Re: [RESEND PATCH] sgl_alloc_order: fix memory leak
To:     Douglas Gilbert <dgilbert@interlog.com>,
        linux-scsi@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org
Cc:     martin.petersen@oracle.com, bvanassche@acm.org
References: <20201015185735.5480-1-dgilbert@interlog.com>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <f1a4c312-2fbf-b149-bd43-7190af75ca24@kernel.dk>
Date:   Fri, 16 Oct 2020 09:31:26 -0600
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On 10/15/20 12:57 PM, Douglas Gilbert wrote:
> sgl_alloc_order() can fail when 'length' is large on a memory
> constrained system. When order > 0 it will potentially be
> making several multi-page allocations with the later ones more
> likely to fail than the earlier one. So it is important that
> sgl_alloc_order() frees up any pages it has obtained before
> returning NULL. In the case when order > 0 it calls the wrong
> free page function and leaks. In testing the leak was
> sufficient to bring down my 8 GiB laptop with OOM.

I've picked this one up, thanks.

-- 
Jens Axboe