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, 85 insertions, 0 deletions

diff --git a/net/bridge/Kconfig b/net/bridge/Kconfig
new file mode 100644
index 000000000..318715c8f
--- /dev/null
+++ b/net/bridge/Kconfig
@@ -0,0 +1,85 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# 802.1d Ethernet Bridging
+#
+
+config BRIDGE
+	tristate "802.1d Ethernet Bridging"
+	select LLC
+	select STP
+	help
+	  If you say Y here, then your Linux box will be able to act as an
+	  Ethernet bridge, which means that the different Ethernet segments it
+	  is connected to will appear as one Ethernet to the participants.
+	  Several such bridges can work together to create even larger
+	  networks of Ethernets using the IEEE 802.1 spanning tree algorithm.
+	  As this is a standard, Linux bridges will cooperate properly with
+	  other third party bridge products.
+
+	  In order to use the Ethernet bridge, you'll need the bridge
+	  configuration tools; see <file:Documentation/networking/bridge.rst>
+	  for location. Please read the Bridge mini-HOWTO for more
+	  information.
+
+	  If you enable iptables support along with the bridge support then you
+	  turn your bridge into a bridging IP firewall.
+	  iptables will then see the IP packets being bridged, so you need to
+	  take this into account when setting up your firewall rules.
+	  Enabling arptables support when bridging will let arptables see
+	  bridged ARP traffic in the arptables FORWARD chain.
+
+	  To compile this code as a module, choose M here: the module
+	  will be called bridge.
+
+	  If unsure, say N.
+
+config BRIDGE_IGMP_SNOOPING
+	bool "IGMP/MLD snooping"
+	depends on BRIDGE
+	depends on INET
+	default y
+	help
+	  If you say Y here, then the Ethernet bridge will be able selectively
+	  forward multicast traffic based on IGMP/MLD traffic received from
+	  each port.
+
+	  Say N to exclude this support and reduce the binary size.
+
+	  If unsure, say Y.
+
+config BRIDGE_VLAN_FILTERING
+	bool "VLAN filtering"
+	depends on BRIDGE
+	depends on VLAN_8021Q
+	default n
+	help
+	  If you say Y here, then the Ethernet bridge will be able selectively
+	  receive and forward traffic based on VLAN information in the packet
+	  any VLAN information configured on the bridge port or bridge device.
+
+	  Say N to exclude this support and reduce the binary size.
+
+	  If unsure, say Y.
+
+config BRIDGE_MRP
+	bool "MRP protocol"
+	depends on BRIDGE
+	default n
+	help
+	  If you say Y here, then the Ethernet bridge will be able to run MRP
+	  protocol to detect loops
+
+	  Say N to exclude this support and reduce the binary size.
+
+	  If unsure, say N.
+
+config BRIDGE_CFM
+	bool "CFM protocol"
+	depends on BRIDGE
+	help
+	  If you say Y here, then the Ethernet bridge will be able to run CFM
+	  protocol according to 802.1Q section 12.14
+
+	  Say N to exclude this support and reduce the binary size.
+
+	  If unsure, say N.