On Tue, May 22, 2018 at 11:12:26PM +0200, Alexander Graf wrote:
Am 22.05.2018 um 21:17 schrieb Daniel Thompson daniel.thompson@linaro.org:
Fixes: #3 Fixed: #8 Signed-off-by: Daniel Thompson daniel.thompson@linaro.org
Notes: This patch tries to capture contributions from a long a varied discussion. I hope I haven't missed anything major.
Thanks to all the contributors to this topic so far!
source/ebbr.rst | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+)
diff --git a/source/ebbr.rst b/source/ebbr.rst index 40f03f173bd9..30a9c6ac2666 100644 --- a/source/ebbr.rst +++ b/source/ebbr.rst @@ -185,6 +185,53 @@ System Volume Format
The system firmware must support GPT partitioning. +It may optionally also support MBR partitioning.
Please make both mandatory.
Will do (or alternatively will just remove this entirely and rely on the underlying UEFI spec to mandate GPT, MBR and el torito).
+On systems where the system firmware binaries reside on the System Volume then +the System Volume must be pre-configured with a partition table and include +protective partitions to reduce risk of accidental destruction of the system +firmware.
+All pre-configured partition tables must use GPT partitioning unless +some immutable feature of the platform (such as a mask programmed boot ROM) +makes this impossible; on such platforms MBR partitioning may be +used as an alternative.
+GPT partitioning +^^^^^^^^^^^^^^^^
+Protective partitions should have the Platform Required Attribute Flag set +unless some immutable feature of the platform makes this impossible.
+It is recommended that automatic system disk partitioning utilities +preserve Platform Required partitions as is, and that manual disk +partitioning utilities provide warnings and/or other safe guards to +reduce risk of accidental removal.
+It is recommended that an implementer on a platform where Platform Required +cannot be set contribute a list of Partition type GUIDs for protective +partitions to the table below. It is further recommended that disk partitioning +utilities treat such partitions in the same manner as those with the Platform +Required Attribute Flag set.
++--------------------------------------+---------------------------------------+ +| Partition type GUID | Comment | ++======================================+=======================================+ +| 00000000-0000-0000-0000-000000000000 | Unused entry (example; do not honour) | ++--------------------------------------+---------------------------------------+
+MBR partitioning +^^^^^^^^^^^^^^^^
+Protective partitions should have a partition type of 0xF8 unless some +immutable feature of the platform makes this impossible.
+It is recommended that disk partitioning utilities treat such +partitions in the same manner as GPT partitions with the Platform +Required Attribute Flag set.
+It is strongly recommended that protective partitions with a type other +than 0xF8 be placed within 1MB of the start of the disk.
What does this sentence mean?
Which bit is unclear?
Based on your feedback and Grant's then how about:
It is recommended that pre-installed protective partitions that are not type 0xF8 be located wholly within 1MB of the start of the disk.
Automatic disk partitioning utilities shall not create partitions within 1MB of the start of the disk. Manual disk partitioning utilities should avoid recommending that partitions start within 1MB of the start of the disk.
Daniel.