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, 53 insertions, 0 deletions

diff --git a/fs/coda/sysctl.c b/fs/coda/sysctl.c
new file mode 100644
index 000000000..0df46f09b
--- /dev/null
+++ b/fs/coda/sysctl.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Sysctl operations for Coda filesystem
+ * Original version: (C) 1996 P. Braam and M. Callahan
+ * Rewritten for Linux 2.1. (C) 1997 Carnegie Mellon University
+ * 
+ * Carnegie Mellon encourages users to contribute improvements to
+ * the Coda project. Contact Peter Braam (coda@cs.cmu.edu).
+ */
+
+#include <linux/sysctl.h>
+
+#include "coda_int.h"
+
+static struct ctl_table_header *fs_table_header;
+
+static const struct ctl_table coda_table[] = {
+	{
+		.procname	= "timeout",
+		.data		= &coda_timeout,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "hard",
+		.data		= &coda_hard,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec
+	},
+	{
+		.procname	= "fake_statfs",
+		.data		= &coda_fake_statfs,
+		.maxlen		= sizeof(int),
+		.mode		= 0600,
+		.proc_handler	= proc_dointvec
+	},
+};
+
+void coda_sysctl_init(void)
+{
+	if ( !fs_table_header )
+		fs_table_header = register_sysctl("coda", coda_table);
+}
+
+void coda_sysctl_clean(void)
+{
+	if ( fs_table_header ) {
+		unregister_sysctl_table(fs_table_header);
+		fs_table_header = NULL;
+	}
+}