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>

1 files changed, 101 insertions, 0 deletions

diff --git a/Documentation/ABI/testing/sysfs-class-extcon b/Documentation/ABI/testing/sysfs-class-extcon
new file mode 100644
index 000000000..f8e705375
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-class-extcon
@@ -0,0 +1,101 @@
+What:		/sys/class/extcon/.../
+Date:		February 2012
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		Provide a place in sysfs for the extcon objects.
+		This allows accessing extcon specific variables.
+		The name of extcon object denoted as ... is the name given
+		with extcon_dev_register.
+
+		One extcon device denotes a single external connector
+		port. An external connector may have multiple cables
+		attached simultaneously. Many of docks, cradles, and
+		accessory cables have such capability. For example,
+		the 30-pin port of Nuri board (/arch/arm/mach-exynos)
+		may have both HDMI and Charger attached, or analog audio,
+		video, and USB cables attached simultaneously.
+
+		If there are cables mutually exclusive with each other,
+		such binary relations may be expressed with extcon_dev's
+		mutually_exclusive array.
+
+What:		/sys/class/extcon/.../name
+Date:		February 2012
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/extcon/.../name shows the name of the extcon
+		object. If the extcon object has an optional callback
+		"show_name" defined, the callback will provide the name with
+		this sysfs node.
+
+What:		/sys/class/extcon/.../state
+Date:		February 2012
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/extcon/.../state shows and stores the cable
+		attach/detach information of the corresponding extcon object.
+		If the extcon object has an optional callback "show_state"
+		defined, the showing function is overridden with the optional
+		callback.
+
+		If the default callback for showing function is used, the
+		format is like this::
+
+		    # cat state
+		    USB_OTG=1
+		    HDMI=0
+		    TA=1
+		    EAR_JACK=0
+		    #
+
+		In this example, the extcon device has USB_OTG and TA
+		cables attached and HDMI and EAR_JACK cables detached.
+
+		In order to update the state of an extcon device, enter a hex
+		state number starting with 0x::
+
+		    # echo 0xHEX > state
+
+		This updates the whole state of the extcon device.
+		Inputs of all the methods are required to meet the
+		mutually_exclusive conditions if they exist.
+
+		It is recommended to use this "global" state interface if
+		you need to set the value atomically. The later state
+		interface associated with each cable cannot update
+		multiple cable states of an extcon device simultaneously.
+
+What:		/sys/class/extcon/.../cable.X/name
+Date:		February 2012
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/extcon/.../cable.X/name shows the name of cable
+		"X" (integer between 0 and 31) of an extcon device.
+
+What:		/sys/class/extcon/.../cable.X/state
+Date:		February 2012
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		The /sys/class/extcon/.../cable.X/state shows and stores the
+		state of cable "X" (integer between 0 and 31) of an extcon
+		device. The state value is either 0 (detached) or 1
+		(attached).
+
+What:		/sys/class/extcon/.../mutually_exclusive/...
+Date:		December 2011
+Contact:	MyungJoo Ham <myungjoo.ham@samsung.com>
+Description:
+		Shows the relations of mutually exclusiveness. For example,
+		if the mutually_exclusive array of extcon device is
+		{0x3, 0x5, 0xC, 0x0}, then the output is::
+
+		    # ls mutually_exclusive/
+		    0x3
+		    0x5
+		    0xc
+		    #
+
+		Note that mutually_exclusive is a sub-directory of the extcon
+		device and the file names under the mutually_exclusive
+		directory show the mutually-exclusive sets, not the contents
+		of the files.