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Date:   Thu, 25 Jun 2020 07:33:38 +0300
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     linux-integrity@vger.kernel.org
Cc:     James Bottomley <James.Bottomley@HansenPartnership.com>,
        Stefan Berger <stefanb@linux.ibm.com>,
        Peter Huewe <peterhuewe@gmx.de>,
        Jason Gunthorpe <jgg@ziepe.ca>, Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jerry Snitselaar <jsnitsel@redhat.com>,
        Sumit Garg <sumit.garg@linaro.org>,
        Alexey Klimov <aklimov@redhat.com>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] tpm: tpm2-space: Resize session and context buffers
 dynamically
Message-ID: <20200625043338.GA370462@linux.intel.com>
References: <20200625042424.370072-1-jarkko.sakkinen@linux.intel.com>
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On Thu, Jun 25, 2020 at 07:24:20AM +0300, Jarkko Sakkinen wrote:
> Re-allocate context and session buffers when needed. Scale them in page
> increments so that the reallocation is only seldomly required, and thus
> causes minimal stress to the system. Add a static maximum limit of four
> pages for buffer sizes.
> 
> Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
> Suggested-by: Stefan Berger <stefanb@linux.ibm.com>
> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

I'd actually consider

#define TPM2_SPACE_DEFAULT_BUFFER_SIZE	PAGE_SIZE
#define TPM2_SPACE_MAX_BUFFER_SIZE	(4 * PAGE_SIZE)

/JQ4KKO