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, 38 insertions, 0 deletions

diff --git a/drivers/scsi/scsi_sysctl.c b/drivers/scsi/scsi_sysctl.c
new file mode 100644
index 000000000..055a03a83
--- /dev/null
+++ b/drivers/scsi/scsi_sysctl.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2003 Christoph Hellwig.
+ */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/sysctl.h>
+
+#include "scsi_logging.h"
+#include "scsi_priv.h"
+
+
+static const struct ctl_table scsi_table[] = {
+	{ .procname	= "logging_level",
+	  .data		= &scsi_logging_level,
+	  .maxlen	= sizeof(scsi_logging_level),
+	  .mode		= 0644,
+	  .proc_handler	= proc_dointvec_minmax,
+	  .extra1	= SYSCTL_ZERO,
+	  .extra2	= SYSCTL_INT_MAX },
+};
+
+static struct ctl_table_header *scsi_table_header;
+
+int __init scsi_init_sysctl(void)
+{
+	scsi_table_header = register_sysctl("dev/scsi", scsi_table);
+	if (!scsi_table_header)
+		return -ENOMEM;
+	return 0;
+}
+
+void scsi_exit_sysctl(void)
+{
+	unregister_sysctl_table(scsi_table_header);
+}