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, 45 insertions, 0 deletions

diff --git a/fs/lockd/netlink.c b/fs/lockd/netlink.c
new file mode 100644
index 000000000..880c42b4f
--- /dev/null
+++ b/fs/lockd/netlink.c
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/lockd.yaml */
+/* YNL-GEN kernel source */
+/* To regenerate run: tools/net/ynl/ynl-regen.sh */
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+#include "netlink.h"
+
+#include <uapi/linux/lockd_netlink.h>
+
+/* LOCKD_CMD_SERVER_SET - do */
+static const struct nla_policy lockd_server_set_nl_policy[LOCKD_A_SERVER_UDP_PORT + 1] = {
+	[LOCKD_A_SERVER_GRACETIME] = { .type = NLA_U32, },
+	[LOCKD_A_SERVER_TCP_PORT] = { .type = NLA_U16, },
+	[LOCKD_A_SERVER_UDP_PORT] = { .type = NLA_U16, },
+};
+
+/* Ops table for lockd */
+static const struct genl_split_ops lockd_nl_ops[] = {
+	{
+		.cmd		= LOCKD_CMD_SERVER_SET,
+		.doit		= lockd_nl_server_set_doit,
+		.policy		= lockd_server_set_nl_policy,
+		.maxattr	= LOCKD_A_SERVER_UDP_PORT,
+		.flags		= GENL_ADMIN_PERM | GENL_CMD_CAP_DO,
+	},
+	{
+		.cmd	= LOCKD_CMD_SERVER_GET,
+		.doit	= lockd_nl_server_get_doit,
+		.flags	= GENL_CMD_CAP_DO,
+	},
+};
+
+struct genl_family lockd_nl_family __ro_after_init = {
+	.name		= LOCKD_FAMILY_NAME,
+	.version	= LOCKD_FAMILY_VERSION,
+	.netnsok	= true,
+	.parallel_ops	= true,
+	.module		= THIS_MODULE,
+	.split_ops	= lockd_nl_ops,
+	.n_split_ops	= ARRAY_SIZE(lockd_nl_ops),
+};