Date: Mon, 13 Feb 2017 17:27:27 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-virtualization@FreeBSD.org Subject: [Bug 211746] [Hyper-V] UEFI VM can't boot from the iso installation disk Message-ID: <bug-211746-27103-ouO1XZMSPL@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-211746-27103@https.bugs.freebsd.org/bugzilla/> References: <bug-211746-27103@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D211746 --- Comment #6 from Marcel Moolenaar <marcel@FreeBSD.org> --- Check in the EFI memory map whether there's runtime-persistent memory at 0x200000 + 45MB (or abouts). Runtime persistent memory are memory allocatio= ns of type runtime, firmware, (e.g. ACPI non-reclaimable), etc. I.e anything t= hat the kernel can't use during runtime. If the memory at 0x200000 isn't free during runtime, then we have a real problem... Some background: FreeBSD makes an invalid or at least a questionable assump= tion that the memory map under EFI is compatible with the memory layout as seen under the BIOS. As time goes by, this will probably be less and less valid.= The staging area is a side-effect of the kernel wanting to be loaded in a contiguous memory region, starting at 0x200000. Something that is can't be = done under EFI without a staging area. To wit: The old (and now removed) Itanium kernel used a virtual address spa= ce for the kernel. The contiguous virtual kernel address mapped to underlying = EFI allocated pages that didn't have to be contiguous. On Itanium the physical memory map could be without addressable memory in the first 4GB even, so no amount of staging would be able to handle that. Hopefully the problem is much more trivial than all of that... --=20 You are receiving this mail because: You are the assignee for the bug.=
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