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, 47 insertions, 0 deletions

diff --git a/net/ceph/Kconfig b/net/ceph/Kconfig
new file mode 100644
index 000000000..7e2528cde
--- /dev/null
+++ b/net/ceph/Kconfig
@@ -0,0 +1,47 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config CEPH_LIB
+	tristate "Ceph core library"
+	depends on INET
+	select CRC32
+	select CRYPTO_AES
+	select CRYPTO_CBC
+	select CRYPTO_GCM
+	select CRYPTO_KRB5
+	select CRYPTO_LIB_SHA256
+	select CRYPTO
+	select KEYS
+	default n
+	help
+	  Choose Y or M here to include cephlib, which provides the
+	  common functionality to both the Ceph filesystem and
+	  to the rados block device (rbd).
+
+	  More information at https://ceph.io/.
+
+	  If unsure, say N.
+
+config CEPH_LIB_PRETTYDEBUG
+	bool "Include file:line in ceph debug output"
+	depends on CEPH_LIB
+	default n
+	help
+	  If you say Y here, debug output will include a filename and
+	  line to aid debugging.  This increases kernel size and slows
+	  execution slightly when debug call sites are enabled (e.g.,
+	  via CONFIG_DYNAMIC_DEBUG).
+
+	  If unsure, say N.
+
+config CEPH_LIB_USE_DNS_RESOLVER
+	bool "Use in-kernel support for DNS lookup"
+	depends on CEPH_LIB
+	select DNS_RESOLVER
+	default n
+	help
+	  If you say Y here, hostnames (e.g. monitor addresses) will
+	  be resolved using the CONFIG_DNS_RESOLVER facility.
+
+	  For information on how to use CONFIG_DNS_RESOLVER consult
+	  Documentation/networking/dns_resolver.rst
+
+	  If unsure, say N.