Add support for the Boot Loader Specification (BLS) type 1 boot entries, as generated by default by systemd's kernel-install when loader=bls.
Given that the format of BLS entries is pretty much the same as PXElinux, reuse the existing library for the parsing logic. BLS type 2 entries are out of scope, as they are effectively just EFI applications and should be booted as such. This implementation is also only allowing a single top-sorting entry to boot, as the standard boot infrastruture currently doesn't support multiple entries per partition-bootmeth tuple. I have a proposed extension to enable that and will post it separately as RFC - that enables the use of `bootflow menu` to select the kernel to boot without jumping through several menus with different behavior as is currently required with extlinux.conf. CI passes all green [1] [1] https://git.u-boot-project.org/u-boot/contributors/alchark/u-boot/-/pipelines/1089 Signed-off-by: Alexey Charkov <[email protected]> --- Changes in v2: - Dropped "default y" to avoid increasing image size for platforms which don't use Freedesktop-style userspace and won't benefit from BLS (thanks Tom) - Fixed typo referring to BLS type 2 when type 1 was meant (thanks Simon) - Added a kerneldoc for parse_label_keys() upon factoring it out, not just when it gets exported to a shared header (thanks Simon) - Shared the pxelinux getfile helper rather than making a third copy of it in the new bootmeth (thanks Simon). It moves to a translation unit of its own, so that PXE_UTILS users without bootstd don't gain a dependency on the bootmeth uclass, and boards without PXE_UTILS don't pay for it - Allocated the entry buffer with ARCH_DMA_MINALIGN rather than 1 (thanks Simon) - Stopped retaining the parsed label in bflow->bootmeth_priv, which the core frees flat and would therefore leak (thanks Simon). It turned out to be worse than a leak: a bootflow is shallow-copied into the bootflow list, so the pointer was shared between the iterator's temporary and the stored copy and could be freed twice. bls_boot() now re-parses bflow->buf, as extlinux does - Added a test for entries found under the '/boot/' prefix rather than at the root of the filesystem (thanks Simon for asking what happens there). No code change was needed - Dropped the number prefix from the driver name (thanks Simon) - Added sandbox tests and updated the bootmeth/bootflow expectations that binding a third bootmeth changes, plus a doc/develop/bootstd page (thanks Simon) - Added a patch hardening the "append" parser. A bare "append" dereferenced NULL, and an "initrd=" at end-of-line computed a negative length before malloc() - Link to v1: https://patch.msgid.link/[email protected] To: [email protected] Cc: Tom Rini <[email protected]> Cc: Alexey Charkov <[email protected]> Cc: Simon Glass <[email protected]> Cc: Daniel Golle <[email protected]> Cc: Johan Jonker <[email protected]> Cc: "Lucien.Jheng" <[email protected]> Cc: Casey Connolly <[email protected]> Cc: Michal Simek <[email protected]> Cc: Peng Fan <[email protected]> Cc: Vincent Jardin <[email protected]> Cc: Denis Mukhin <[email protected]> Cc: Aristo Chen <[email protected]> Cc: Quentin Schulz <[email protected]> Cc: Marek Vasut <[email protected]> --- Alexey Charkov (13): pxe_utils: fix W=1 kernel-doc warnings pxe_utils: accept "options" as synonym for "append" pxe_utils: harden the "append" parser against malformed input pxe_utils: extract per-entry key parsing into parse_label_keys() pxe_utils: export per-entry label helpers pxe_utils: optionally ignore unknown keys in parse_label_keys() pxe_utils: accept "title" inside a label as a synonym for "menu label" bootmeth: share the pxelinux getfile helper boot: add a minimal bootmeth for the Boot Loader Specification test: bootstd: add a BLS entry to the Fedora fixture image sandbox: enable BLS boot method test: bootstd: cover BLS entries below a prefix doc: bootstd: describe the BLS bootmeth arch/sandbox/dts/test.dts | 12 + boot/Kconfig | 24 ++ boot/Makefile | 2 + boot/bootmeth_bls.c | 370 +++++++++++++++++++++++++++++++ boot/bootmeth_extlinux.c | 20 -- boot/bootmeth_pxe.c | 22 +- boot/bootmeth_pxe_common.c | 34 +++ boot/pxe_utils.c | 146 +++++++----- configs/sandbox_defconfig | 1 + doc/develop/bootstd/bls.rst | 56 +++++ doc/develop/bootstd/index.rst | 1 + doc/develop/bootstd/overview.rst | 1 + include/extlinux.h | 23 ++ include/pxe_utils.h | 62 ++++++ test/boot/bootdev.c | 14 ++ test/boot/bootflow.c | 467 +++++++++++++++++++++++++++++++-------- test/boot/bootmeth.c | 38 +++- test/py/tests/test_ut.py | 122 ++++++++-- 18 files changed, 1200 insertions(+), 215 deletions(-) --- base-commit: 2d379a529c257606946831a6dac1c37de6a3f8c0 change-id: 20260604-bls-db6a30b913ae Best regards, -- Alexey Charkov <[email protected]>
