> On 8 Jul 2022, at 22:34, Demi Marie Obenour <d...@invisiblethingslab.com> > wrote: > > The EFI System Resource Table (ESRT) is necessary for fwupd to identify > firmware updates to install. According to the UEFI specification §23.4, > the ESRT shall be stored in memory of type EfiBootServicesData. However, > memory of type EfiBootServicesData is considered general-purpose memory > by Xen, so the ESRT needs to be moved somewhere where Xen will not > overwrite it. Copy the ESRT to memory of type EfiRuntimeServicesData, > which Xen will not reuse. dom0 can use the ESRT if (and only if) it is > in memory of type EfiRuntimeServicesData. > > Earlier versions of this patch reserved the memory in which the ESRT was > located. This created awkward alignment problems, and required either > splitting the E820 table or wasting memory. It also would have required > a new platform op for dom0 to use to indicate if the ESRT is reserved. > By copying the ESRT into EfiRuntimeServicesData memory, the E820 table > does not need to be modified, and dom0 can just check the type of the > memory region containing the ESRT. The copy is only done if the ESRT is > not already in EfiRuntimeServicesData memory, avoiding memory leaks on > repeated kexec.
Hi, > > See https://lore.kernel.org/xen-devel/20200818184018.GN1679@mail-itl/T/ > for details. Tested using qemu-system-x86_64 and xen.efi. Not sure if “Tested using qemu-system-x86_64 and xen.efi.” should be added in a section like this under your S-o-b: --- Tested using qemu-system-x86_64 and xen.efi. --- > > Signed-off-by: Demi Marie Obenour <d...@invisiblethingslab.com> I’ve tested UEFI boot on an arm64 machine and Xen+Dom0+ACPI boots fine. So if in v10 you don’t change anything apart from the style issues mentioned by Jan, you can keep my tested-by: Tested-by: Luca Fancellu <luca.fance...@arm.com> > > +static void __init efi_relocate_esrt(EFI_SYSTEM_TABLE *SystemTable) > +{ > + EFI_STATUS status; > + UINTN info_size = 0, map_key, mdesc_size; > + void *memory_map = NULL; > + UINT32 ver; > + unsigned int i; > + > + for ( ; ; ) { Here, coding style wants the brackets on a new line (Jan comment): for ( ; ; ) { > + status = efi_bs->GetMemoryMap(&info_size, memory_map, &map_key, > + &mdesc_size, &ver); > Cheers, Luca
