diff options
| author | Ulises Mendez Martinez <umendez@google.com> | 2026-09-04 15:07:09 +0000 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@kernel.org> | 2026-09-13 18:15:43 -0700 |
| commit | 7e61560628d17ea6b1d8ee370f6d42694cff8758 (patch) | |
| tree | e6080164b2f4c4c419894bdb3ce4d956ca9a98c5 /Documentation/devicetree/dynamic-resolution-notes.rst | |
| download | linux-stable-7e61560628d17ea6b1d8ee370f6d42694cff8758.tar.gz linux-stable-7e61560628d17ea6b1d8ee370f6d42694cff8758.zip | |
objtool: Validate disassembler headers in libopcodes probegrafted
commit 3f2de814c059 ("objtool: Fix libopcodes linking with static libraries")
tested for libopcodes availability by linking a test snippet with a forward
declaration of disassemble_init_for_target().
However, testing symbol linkage with an extern declaration only verifies
the presence of the library (.so/.a) and bypasses checking for development
headers (binutils-dev). On systems where libopcodes is present without
development headers installed, the probe succeeds, enabling BUILD_DISAS.
Subsequent compilation of objtool then fails:
fatal error: 'bfd.h' file not found
113 | #include <bfd.h>
Additionally, the probe invokes $(HOSTCC) without $(HOSTCFLAGS), ignoring
any sysroot or include flags specified for the host compiler.
Fix this by including <bfd.h> and <dis-asm.h> directly in the test snippet,
passing $(HOSTCFLAGS) so host compiler options are respected, and defining
PACKAGE="objtool" to satisfy the configuration check in <bfd.h>.
Fixes: 3f2de814c059 ("objtool: Fix libopcodes linking with static libraries")
Fixes: 436326bc525d ("objtool: fix build failure due to missing libopcodes check")
Reported-by: Alice Ryhl <aliceryhl@google.com>
Assisted-by: Antigravity:Gemini-Next
Signed-off-by: Ulises Mendez Martinez <umendez@google.com>
Link: https://patch.msgid.link/20260904150710.2997558-1-umendez@google.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Diffstat (limited to 'Documentation/devicetree/dynamic-resolution-notes.rst')
| -rw-r--r-- | Documentation/devicetree/dynamic-resolution-notes.rst | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/Documentation/devicetree/dynamic-resolution-notes.rst b/Documentation/devicetree/dynamic-resolution-notes.rst new file mode 100644 index 000000000..f81ad8daa --- /dev/null +++ b/Documentation/devicetree/dynamic-resolution-notes.rst @@ -0,0 +1,27 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================= +Devicetree Dynamic Resolver Notes +================================= + +This document describes the implementation of the in-kernel +DeviceTree resolver, residing in drivers/of/resolver.c + +How the resolver works +---------------------- + +The resolver is given as an input an arbitrary tree compiled with the +proper dtc option and having a /plugin/ tag. This generates the +appropriate __fixups__ & __local_fixups__ nodes. + +In sequence the resolver works by the following steps: + +1. Get the maximum device tree phandle value from the live tree + 1. +2. Adjust all the local phandles of the tree to resolve by that amount. +3. Using the __local__fixups__ node information adjust all local references + by the same amount. +4. For each property in the __fixups__ node locate the node it references + in the live tree. This is the label used to tag the node. +5. Retrieve the phandle of the target of the fixup. +6. For each fixup in the property locate the node:property:offset location + and replace it with the phandle value. |