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Subject: Re: [PATCH 3/3] /dev/mem: Do not map unaccepted memory
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To: Adrian Hunter <adrian.hunter@intel.com>,
 "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
 Borislav Petkov <bp@alien8.de>, Andrew Morton <akpm@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>, Mike Rapoport <rppt@linux.ibm.com>,
 Lorenzo Stoakes <lstoakes@gmail.com>, Tom Lendacky
 <thomas.lendacky@amd.com>, Baoquan He <bhe@redhat.com>,
 Vivek Goyal <vgoyal@redhat.com>, Dave Young <dyoung@redhat.com>,
 linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
 linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org,
 kexec@lists.infradead.org
References: <20230906073902.4229-1-adrian.hunter@intel.com>
 <20230906073902.4229-4-adrian.hunter@intel.com>
From: Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20230906073902.4229-4-adrian.hunter@intel.com>
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On 9/6/23 00:39, Adrian Hunter wrote:
> Support for unaccepted memory was added recently, refer commit
> dcdfdd40fa82 ("mm: Add support for unaccepted memory"), whereby
> a virtual machine may need to accept memory before it can be used.
> 
> Do not map unaccepted memory because it can cause the guest to fail.

Doesn't /dev/mem already provide a billion ways for someone to shoot
themselves in the foot?  TDX seems to have added the 1,000,000,001st.
Is this really worth patching?