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* allocation zone extensions for the firmware linker/loader
@ 2017-06-02 15:45 Laszlo Ersek
  2017-06-02 15:59 ` [qemu PATCH 0/7] bios-linker-loader: introduce the NOACPI hint and the 64-bit zone for ALLOCATE Laszlo Ersek
                   ` (4 more replies)
  0 siblings, 5 replies; 22+ messages in thread
From: Laszlo Ersek @ 2017-06-02 15:45 UTC (permalink / raw)
  To: SeaBIOS devel list, qemu devel list, edk2-devel-ml01
  Cc: Kevin O'Connor, Michael S. Tsirkin, Ard Biesheuvel,
	Ben Warren, Dongjiu Geng, Igor Mammedov,
	Jordan Justen (Intel address), Leif Lindholm (Linaro address),
	Shannon Zhao, Stefan Berger, Xiao Guangrong

Hi,

this message is cross-posted to three lists (qemu, seabios, edk2). I'll
follow up with three patch series, one series for each project. I'll
cross-post all of the patches as well, but I'll add the project name in
the "bag of tags" in the subject lines.

The QEMU series introduces two extensions to the ALLOCATE firmware
linker/loader command.

One extension is a new allocation zone, with value 3, for allowing the
firmware to allocate the fw_cfg blobs in 64-bit address space.

The other extension is a repurposing of the most significant bit (bit 7)
in the zone field. This bit becomes orthogonal to the rest of the zone
field. If the bit is set, it means that QEMU promises the firmware that
the blob referenced by the ALLOCATE command contains no ACPI tables at all.

After introducing these, the QEMU series puts them to use, covering all
of the currently generated ALLOCATE commands, as appropriate. Among the
benefits we can mention
- the removal of the OVMF ACPI SDT Header Probe suppressor from VMGENID
(and from any similar future devices),
- and the fact that the "virt" machine type (and maybe other machine
types) of the arm/aarch64 target will no longer require RAM under 4GB
for ACPI to work.

Both of these extensions are irrelevant for SeaBIOS, therefore the
SeaBIOS patches simply mask out bit 7 (for ignoring the "no ACPI
content" hint), and fall back to the HIGH zone (= 32-bit address space)
when the 64-bit zone is permitted.

In other words, SeaBIOS needs some patches to recognize the new zone
values, but beyond that, the behavior is unchanged.

Both extensions are important for virtual UEFI firmware (OVMF in x86
guests and ArmVirtQemu in aarch64 guests). The edk2 patches add support
to OvmfPkg/AcpiPlatformDxe for the extensions. Please see the commit
messages for details (all the extensions are explained in detail in the
relevant patches for all of the projects).

The patches can cause linker/loader breakage when old firmware is booted
on new QEMU. However, that's no problem (it's nothing new), the next
release of QEMU should bundle the new firmware binaries as always.

New firmware will continue running on old QEMU without issues.

(In case you have sent me emails about this in the last few tens of
hours, please know that I'm not ignoring them, I just haven't seen /
read them. Reading emails every five minutes makes focused work
impossible, so when I'm busy, I tend to read email once per day.)

Thanks
Laszlo


^ permalink raw reply	[flat|nested] 22+ messages in thread

end of thread, other threads:[~2017-06-12 16:04 UTC | newest]

Thread overview: 22+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-06-02 15:45 allocation zone extensions for the firmware linker/loader Laszlo Ersek
2017-06-02 15:59 ` [qemu PATCH 0/7] bios-linker-loader: introduce the NOACPI hint and the 64-bit zone for ALLOCATE Laszlo Ersek
2017-06-02 16:00   ` [qemu PATCH 1/7] hw/acpi/bios-linker-loader: expose allocation zone as an enum Laszlo Ersek
2017-06-02 16:00   ` [qemu PATCH 2/7] hw/acpi/bios-linker-loader: introduce "no ACPI tables" content hint for ALLOC Laszlo Ersek
2017-06-02 16:00   ` [qemu PATCH 3/7] hw/acpi/bios-linker-loader: introduce BIOS_LINKER_LOADER_ALLOC_ZONE_64BIT Laszlo Ersek
2017-06-02 16:00   ` [qemu PATCH 4/7] hw/acpi/nvdimm: ask the firmware to allocate NVDIMM_DSM_MEM_FILE as NOACPI Laszlo Ersek
2017-06-02 16:00   ` [qemu PATCH 5/7] hw/acpi/vmgenid: ask the fw to alloc VMGENID_GUID_FW_CFG_FILE " Laszlo Ersek
2017-06-02 16:00   ` [qemu PATCH 6/7] hw/i386/acpi-build: ask the fw to alloc ACPI_BUILD_TPMLOG_FILE with 64bit/NOACPI Laszlo Ersek
2017-06-02 16:00   ` [qemu PATCH 7/7] hw/arm/virt-acpi-build: make the fw alloc blobs with ACPI tables as 64bit Laszlo Ersek
2017-06-02 16:02 ` [seabios PATCH 0/2] romfile_loader: cope with the UEFI-oriented allocation extensions Laszlo Ersek
2017-06-02 16:02   ` [seabios PATCH 1/2] romfile_loader: alloc: cope with the UEFI-oriented NOACPI content hint Laszlo Ersek
2017-06-02 16:02   ` [seabios PATCH 2/2] romfile_loader: alloc: cope with the UEFI-oriented 64BIT zone hint Laszlo Ersek
2017-06-02 16:03 ` [edk2 PATCH 0/3] OvmfPkg/AcpiPlatformDxe: NOACPI hint and 64-bit zone in fw_cfg blob alloc Laszlo Ersek
2017-06-02 16:03   ` [edk2 PATCH 1/3] OvmfPkg/AcpiPlatformDxe: rename BLOB.HostsOnlyTableData to BLOB.Releasable Laszlo Ersek
2017-06-02 16:03   ` [edk2 PATCH 2/3] OvmfPkg/AcpiPlatformDxe: support NOACPI content hint in ALLOCATE command Laszlo Ersek
2017-06-02 16:03   ` [edk2 PATCH 3/3] OvmfPkg/AcpiPlatformDxe: support 64-bit zone " Laszlo Ersek
     [not found] ` <20170602191230-mutt-send-email-mst@kernel.org>
2017-06-02 23:20   ` allocation zone extensions for the firmware linker/loader Laszlo Ersek
2017-06-03  7:36 ` Laszlo Ersek
2017-06-05  9:54   ` [Qemu-devel] " Igor Mammedov
2017-06-06 17:52     ` Laszlo Ersek
     [not found]   ` <20170605185815-mutt-send-email-mst@kernel.org>
2017-06-06 18:10     ` Laszlo Ersek
     [not found]       ` <20170608204207-mutt-send-email-mst@kernel.org>
2017-06-12 16:05         ` Paolo Bonzini

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