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Date:   Sun, 12 Mar 2023 03:25:05 +0200
From:   "jarkko@kernel.org" <jarkko@kernel.org>
To:     "Huang, Kai" <kai.huang@intel.com>
Cc:     "haitao.huang@linux.intel.com" <haitao.huang@linux.intel.com>,
        "linux-sgx@vger.kernel.org" <linux-sgx@vger.kernel.org>,
        "Chatre, Reinette" <reinette.chatre@intel.com>,
        "Dhanraj, Vijay" <vijay.dhanraj@intel.com>,
        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>
Subject: Re: [RFC PATCH v4 2/4] x86/sgx: Implement support for MADV_WILLNEED
Message-ID: <ZA0p4Kf8sLcGBAJb@kernel.org>
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On Tue, Mar 07, 2023 at 11:32:15PM +0000, Huang, Kai wrote:
> And in following mmap()s in which we want to map a small range of enclave:
> 
> 	encl_addr = mmap(encl_addr, MAP_SHARED|MAP_FIXED, encl_fd,
> 			(encl_addr - encl_base) >> PAGE_SHIFT);
> 
> ?
> 
> Anything wrong above?

I'm not sure I fully comprehended your response because it was
honestly a bit scattered so please correct me if I'm missing
something but: why a process would want to map a small range
of an enclave?

You anyway most likely want to enter to the enclave. Is this
for ptrace()?

BR, Jarkko