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Date:   Mon, 5 Sep 2022 20:20:18 -0700
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Subject: Re: [PATCH RFC] x86/sgx: Use a heap allocated list head for
 unsanitized pages
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To:     Jarkko Sakkinen <jarkko@kernel.org>, linux-sgx@vger.kernel.org
Cc:     Haitao Huang <haitao.huang@linux.intel.com>,
        Vijay Dhanraj <vijay.dhanraj@intel.com>,
        Reinette Chatre <reinette.chatre@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Kai Huang <kai.huang@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" <x86@kernel.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        "open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)" 
        <linux-kernel@vger.kernel.org>
References: <20220906031230.107108-1-jarkko@kernel.org>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20220906031230.107108-1-jarkko@kernel.org>
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On 9/5/22 20:12, Jarkko Sakkinen wrote:
> Allocate the list head for the unsanitized pages from heap, and transfer
> its to ownership to ksgxd, which takes care of destroying it. Remove
> sgx_dirty_page_list, as a global list is no longer required.
> 
> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> ---
> Depends on https://lore.kernel.org/linux-sgx/20220906000221.34286-1-jarkko@kernel.org/T/#t
> Would this be plausible?
> ---
>  arch/x86/kernel/cpu/sgx/main.c | 44 ++++++++++++++++++++++++----------
>  1 file changed, 31 insertions(+), 13 deletions(-)

What's the benefit?  I guess it saves 16 bytes of kernel image for ~20
lines of code.  Does it add more than 16 bytes to kernel text? ;)