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Peter Anvin" , "Tom Lendacky" , "Kiryl Shutsemau (Meta)" , linux-kernel@vger.kernel.org, "Mike Rapoport" , linux-mm@kvack.org Message-Id: In-Reply-To: References: <20261102113127.161823-1-pankaj.gupta@amd.com> Subject: Re: [PATCH] x86/unaccepted_memory: Do not accept ranges that are no longer E820 RAM Content-Type: text/plain Content-Transfer-Encoding: 7bit On Mon, 2 Nov 2026, at 13:01, Gupta, Pankaj wrote: >>>> >>> Can we just disallow memmap= when running in a confidential VM? >> >> My experiments showed: memmap itself don't have a problem but memap >> with a hole is causing crash. >> >> There might be some usecases which are already using this, e.g: >> >> https://lore.kernel.org/all/20261029-cma-multi-v1-0-2cbced8b5cb7@kernel.org/ >> >> > Its also good to have a general safeguard to not accept memory that is > not marked as RAM in e820? > Personally, I think all these command line hacks should be avoided in confidential VMs, on the basis that the firmware's view of memory should be in sync with the OS.