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, 138 insertions, 0 deletions

diff --git a/drivers/dma/idxd/debugfs.c b/drivers/dma/idxd/debugfs.c
new file mode 100644
index 000000000..ad4245cb3
--- /dev/null
+++ b/drivers/dma/idxd/debugfs.c
@@ -0,0 +1,138 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2021 Intel Corporation. All rights rsvd. */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/debugfs.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <uapi/linux/idxd.h>
+#include "idxd.h"
+#include "registers.h"
+
+static struct dentry *idxd_debugfs_dir;
+
+static void dump_event_entry(struct idxd_device *idxd, struct seq_file *s,
+			     u16 index, int *count, bool processed)
+{
+	struct idxd_evl *evl = idxd->evl;
+	struct dsa_evl_entry *entry;
+	struct dsa_completion_record *cr;
+	u64 *raw;
+	int i;
+	int evl_strides = evl_ent_size(idxd) / sizeof(u64);
+
+	entry = (struct dsa_evl_entry *)evl->log + index;
+
+	if (!entry->e.desc_valid)
+		return;
+
+	seq_printf(s, "Event Log entry %d (real index %u) processed: %u\n",
+		   *count, index, processed);
+
+	seq_printf(s, "desc valid %u wq idx valid %u\n"
+		   "batch %u fault rw %u priv %u error 0x%x\n"
+		   "wq idx %u op %#x pasid %u batch idx %u\n"
+		   "fault addr %#llx\n",
+		   entry->e.desc_valid, entry->e.wq_idx_valid,
+		   entry->e.batch, entry->e.fault_rw, entry->e.priv,
+		   entry->e.error, entry->e.wq_idx, entry->e.operation,
+		   entry->e.pasid, entry->e.batch_idx, entry->e.fault_addr);
+
+	cr = &entry->cr;
+	seq_printf(s, "status %#x result %#x fault_info %#x bytes_completed %u\n"
+		   "fault addr %#llx inv flags %#x\n\n",
+		   cr->status, cr->result, cr->fault_info, cr->bytes_completed,
+		   cr->fault_addr, cr->invalid_flags);
+
+	raw = (u64 *)entry;
+
+	for (i = 0; i < evl_strides; i++)
+		seq_printf(s, "entry[%d] = %#llx\n", i, raw[i]);
+
+	seq_puts(s, "\n");
+	*count += 1;
+}
+
+static int debugfs_evl_show(struct seq_file *s, void *d)
+{
+	struct idxd_device *idxd = s->private;
+	struct idxd_evl *evl = idxd->evl;
+	union evl_status_reg evl_status;
+	u16 h, t, evl_size, i;
+	int count = 0;
+	bool processed = true;
+
+	if (!evl || !evl->log)
+		return 0;
+
+	mutex_lock(&evl->lock);
+
+	evl_status.bits = ioread64(idxd->reg_base + IDXD_EVLSTATUS_OFFSET);
+	t = evl_status.tail;
+	h = evl_status.head;
+	evl_size = evl->size;
+
+	seq_printf(s, "Event Log head %u tail %u interrupt pending %u\n\n",
+		   evl_status.head, evl_status.tail, evl_status.int_pending);
+
+	i = t;
+	while (1) {
+		i = (i + 1) % evl_size;
+		if (i == t)
+			break;
+
+		if (processed && i == h)
+			processed = false;
+		dump_event_entry(idxd, s, i, &count, processed);
+	}
+
+	mutex_unlock(&evl->lock);
+	return 0;
+}
+
+DEFINE_SHOW_ATTRIBUTE(debugfs_evl);
+
+int idxd_device_init_debugfs(struct idxd_device *idxd)
+{
+	if (IS_ERR_OR_NULL(idxd_debugfs_dir))
+		return 0;
+
+	idxd->dbgfs_dir = debugfs_create_dir(dev_name(idxd_confdev(idxd)), idxd_debugfs_dir);
+	if (IS_ERR(idxd->dbgfs_dir))
+		return PTR_ERR(idxd->dbgfs_dir);
+
+	if (idxd->evl) {
+		idxd->dbgfs_evl_file = debugfs_create_file("event_log", 0400,
+							   idxd->dbgfs_dir, idxd,
+							   &debugfs_evl_fops);
+		if (IS_ERR(idxd->dbgfs_evl_file)) {
+			debugfs_remove_recursive(idxd->dbgfs_dir);
+			idxd->dbgfs_dir = NULL;
+			return PTR_ERR(idxd->dbgfs_evl_file);
+		}
+	}
+
+	return 0;
+}
+
+void idxd_device_remove_debugfs(struct idxd_device *idxd)
+{
+	debugfs_remove_recursive(idxd->dbgfs_dir);
+}
+
+int idxd_init_debugfs(void)
+{
+	if (!debugfs_initialized())
+		return 0;
+
+	idxd_debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+	if (IS_ERR(idxd_debugfs_dir))
+		return  PTR_ERR(idxd_debugfs_dir);
+	return 0;
+}
+
+void idxd_remove_debugfs(void)
+{
+	debugfs_remove_recursive(idxd_debugfs_dir);
+}