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, 51 insertions, 0 deletions

diff --git a/drivers/hid/hid-keytouch.c b/drivers/hid/hid-keytouch.c
new file mode 100644
index 000000000..b9abd53a5
--- /dev/null
+++ b/drivers/hid/hid-keytouch.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  HID driver for Keytouch devices not fully compliant with HID standard
+ *
+ *  Copyright (c) 2011 Jiri Kosina
+ */
+
+/*
+ */
+
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+
+#include "hid-ids.h"
+
+/* Replace the broken report descriptor of this device with rather
+ * a default one */
+static const __u8 keytouch_fixed_rdesc[] = {
+0x05, 0x01, 0x09, 0x06, 0xa1, 0x01, 0x05, 0x07, 0x19, 0xe0, 0x29, 0xe7, 0x15,
+0x00, 0x25, 0x01, 0x75, 0x01, 0x95, 0x08, 0x81, 0x02, 0x95, 0x01, 0x75, 0x08,
+0x81, 0x01, 0x95, 0x03, 0x75, 0x01, 0x05, 0x08, 0x19, 0x01, 0x29, 0x03, 0x91,
+0x02, 0x95, 0x05, 0x75, 0x01, 0x91, 0x01, 0x95, 0x06, 0x75, 0x08, 0x15, 0x00,
+0x26, 0xff, 0x00, 0x05, 0x07, 0x19, 0x00, 0x2a, 0xff, 0x00, 0x81, 0x00, 0xc0
+};
+
+static const __u8 *keytouch_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+		unsigned int *rsize)
+{
+	hid_info(hdev, "fixing up Keytouch IEC report descriptor\n");
+
+	*rsize = sizeof(keytouch_fixed_rdesc);
+	return keytouch_fixed_rdesc;
+}
+
+static const struct hid_device_id keytouch_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_KEYTOUCH, USB_DEVICE_ID_KEYTOUCH_IEC) },
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, keytouch_devices);
+
+static struct hid_driver keytouch_driver = {
+	.name = "keytouch",
+	.id_table = keytouch_devices,
+	.report_fixup = keytouch_report_fixup,
+};
+module_hid_driver(keytouch_driver);
+
+MODULE_DESCRIPTION("HID driver for Keytouch devices not fully compliant with HID standard");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Jiri Kosina");