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From:   Jens Wiklander <jens.wiklander@linaro.org>
Date:   Thu, 10 Jun 2021 11:08:16 +0200
Message-ID: <CAHUa44Erb6bVFEU=xDoRj4KHn1rMFaEPZfS0H24zR+XgGAoLUQ@mail.gmail.com>
Subject: Re: [PATCH 6/7] firmware: tee_bnxt: use tee_shm_alloc_kernel_buf()
To:     Tyler Hicks <tyhicks@linux.microsoft.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        OP-TEE TrustedFirmware <op-tee@lists.trustedfirmware.org>,
        Sumit Garg <sumit.garg@linaro.org>,
        Herbert Xu <herbert@gondor.apana.org.au>,
        Sakkinen <jarkko.sakkinen@linux.intel.com>,
        Sasha Levin <sashal@kernel.org>,
        Thirupathaiah Annapureddy <thiruan@microsoft.com>,
        Vikas Gupta <vikas.gupta@broadcom.com>,
        "David S . Miller" <davem@davemloft.net>
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On Wed, Jun 9, 2021 at 4:58 PM Tyler Hicks <tyhicks@linux.microsoft.com> wrote:
>
> On 2021-06-09 12:23:23, Jens Wiklander wrote:
> > Uses the new simplified tee_shm_alloc_kernel_buf() function instead of
> > the old deprecated tee_shm_alloc() function which required specific
> > TEE_SHM-flags.
> >
> > Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>
>
> Since this series is essentially a rewrite of the shm allocation logic,
> it is worth pointing out that the rewrite still uses contiguous
> allocations (from alloc_pages()). The tee_bnxt_fw driver is performing
> an order-10 allocation which is the max, by default. I've only tested
> tee_bnxt_fw when it was built-in to the kernel and tee_bnxt_fw_probe()
> was called early in boot but I suspect that it might not succeed when
> built as a module and loaded later after memory is segmented. I think
> this driver would benefit from being able to request a non-contiguous
> allocation.
>
> Is this rewrite a good time to offer drivers a way to perform a
> non-contiguous allocation?

Good idea, I'll look into that. I'll add it as a separate patch if it works OK.

Cheers,
Jens