kbuild: rust: keep Rust objects out of Clang LTO with inline helpersgrafted

Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit
`objtool` errors such as:

    vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a:
    can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd

The reason is that in such builds, the Clang invocation that compiles
the combined Rust plus helpers bitcode emits LLVM bitcode (again) --
the final code generation happens in the linker's LTO step, which the
`-mllvm` trap options passed to Clang do not reach.

This, in turn, means that unreachable traps are missing, and the
impossible paths do not merely fallthrough to the next symbol, but past
the end of their own section, since LTO builds place each function in
its own section.

Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always
emits machine code directly, with the traps in place.

Assisted-by: LLM
Cc: Gary Guo <gary@garyguo.net>
Cc: Boqun Feng <boqun@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Matthew Maurer <mmaurer@google.com>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust")
Acked-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

1 files changed, 637 insertions, 0 deletions

diff --git a/drivers/usb/host/uhci-debug.c b/drivers/usb/host/uhci-debug.c
new file mode 100644
index 000000000..e91ec6a4f
--- /dev/null
+++ b/drivers/usb/host/uhci-debug.c
@@ -0,0 +1,637 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * UHCI-specific debugging code. Invaluable when something
+ * goes wrong, but don't get in my face.
+ *
+ * Kernel visible pointers are surrounded in []s and bus
+ * visible pointers are surrounded in ()s
+ *
+ * (C) Copyright 1999 Linus Torvalds
+ * (C) Copyright 1999-2001 Johannes Erdfelt
+ */
+
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/debugfs.h>
+#include <asm/io.h>
+
+#include "uhci-hcd.h"
+
+#define EXTRA_SPACE	1024
+
+static struct dentry *uhci_debugfs_root;
+
+#ifdef CONFIG_DYNAMIC_DEBUG
+
+/* Handle REALLY large printks so we don't overflow buffers */
+static void lprintk(char *buf)
+{
+	char *p;
+
+	/* Just write one line at a time */
+	while (buf) {
+		p = strchr(buf, '\n');
+		if (p)
+			*p = 0;
+		printk(KERN_DEBUG "%s\n", buf);
+		buf = p;
+		if (buf)
+			buf++;
+	}
+}
+
+static int uhci_show_td(struct uhci_hcd *uhci, struct uhci_td *td, char *buf,
+			int len, int space)
+{
+	char *out = buf;
+	char *spid;
+	u32 status, token;
+
+	status = td_status(uhci, td);
+	out += sprintf(out, "%*s[%p] link (%08x) ", space, "", td,
+		hc32_to_cpu(uhci, td->link));
+	out += sprintf(out, "e%d %s%s%s%s%s%s%s%s%s%sLength=%x ",
+		((status >> 27) & 3),
+		(status & TD_CTRL_SPD) ?      "SPD " : "",
+		(status & TD_CTRL_LS) ?       "LS " : "",
+		(status & TD_CTRL_IOC) ?      "IOC " : "",
+		(status & TD_CTRL_ACTIVE) ?   "Active " : "",
+		(status & TD_CTRL_STALLED) ?  "Stalled " : "",
+		(status & TD_CTRL_DBUFERR) ?  "DataBufErr " : "",
+		(status & TD_CTRL_BABBLE) ?   "Babble " : "",
+		(status & TD_CTRL_NAK) ?      "NAK " : "",
+		(status & TD_CTRL_CRCTIMEO) ? "CRC/Timeo " : "",
+		(status & TD_CTRL_BITSTUFF) ? "BitStuff " : "",
+		status & 0x7ff);
+	if (out - buf > len)
+		goto done;
+
+	token = td_token(uhci, td);
+	switch (uhci_packetid(token)) {
+		case USB_PID_SETUP:
+			spid = "SETUP";
+			break;
+		case USB_PID_OUT:
+			spid = "OUT";
+			break;
+		case USB_PID_IN:
+			spid = "IN";
+			break;
+		default:
+			spid = "?";
+			break;
+	}
+
+	out += sprintf(out, "MaxLen=%x DT%d EndPt=%x Dev=%x, PID=%x(%s) ",
+		token >> 21,
+		((token >> 19) & 1),
+		(token >> 15) & 15,
+		(token >> 8) & 127,
+		(token & 0xff),
+		spid);
+	out += sprintf(out, "(buf=%08x)\n", hc32_to_cpu(uhci, td->buffer));
+
+done:
+	if (out - buf > len)
+		out += sprintf(out, " ...\n");
+	return out - buf;
+}
+
+static int uhci_show_urbp(struct uhci_hcd *uhci, struct urb_priv *urbp,
+			char *buf, int len, int space)
+{
+	char *out = buf;
+	struct uhci_td *td;
+	int i, nactive, ninactive;
+	char *ptype;
+
+
+	out += sprintf(out, "urb_priv [%p] ", urbp);
+	out += sprintf(out, "urb [%p] ", urbp->urb);
+	out += sprintf(out, "qh [%p] ", urbp->qh);
+	out += sprintf(out, "Dev=%d ", usb_pipedevice(urbp->urb->pipe));
+	out += sprintf(out, "EP=%x(%s) ", usb_pipeendpoint(urbp->urb->pipe),
+			(usb_pipein(urbp->urb->pipe) ? "IN" : "OUT"));
+	if (out - buf > len)
+		goto done;
+
+	switch (usb_pipetype(urbp->urb->pipe)) {
+	case PIPE_ISOCHRONOUS: ptype = "ISO"; break;
+	case PIPE_INTERRUPT: ptype = "INT"; break;
+	case PIPE_BULK: ptype = "BLK"; break;
+	default:
+	case PIPE_CONTROL: ptype = "CTL"; break;
+	}
+
+	out += sprintf(out, "%s%s", ptype, (urbp->fsbr ? " FSBR" : ""));
+	out += sprintf(out, " Actlen=%d%s", urbp->urb->actual_length,
+			(urbp->qh->type == USB_ENDPOINT_XFER_CONTROL ?
+				"-8" : ""));
+
+	if (urbp->urb->unlinked)
+		out += sprintf(out, " Unlinked=%d", urbp->urb->unlinked);
+	out += sprintf(out, "\n");
+
+	if (out - buf > len)
+		goto done;
+
+	i = nactive = ninactive = 0;
+	list_for_each_entry(td, &urbp->td_list, list) {
+		if (urbp->qh->type != USB_ENDPOINT_XFER_ISOC &&
+				(++i <= 10 || debug > 2)) {
+			out += sprintf(out, "%*s%d: ", space + 2, "", i);
+			out += uhci_show_td(uhci, td, out,
+					len - (out - buf), 0);
+			if (out - buf > len)
+				goto tail;
+		} else {
+			if (td_status(uhci, td) & TD_CTRL_ACTIVE)
+				++nactive;
+			else
+				++ninactive;
+		}
+	}
+	if (nactive + ninactive > 0)
+		out += sprintf(out,
+				"%*s[skipped %d inactive and %d active TDs]\n",
+				space, "", ninactive, nactive);
+done:
+	if (out - buf > len)
+		out += sprintf(out, " ...\n");
+tail:
+	return out - buf;
+}
+
+static int uhci_show_qh(struct uhci_hcd *uhci,
+		struct uhci_qh *qh, char *buf, int len, int space)
+{
+	char *out = buf;
+	int i, nurbs;
+	__hc32 element = qh_element(qh);
+	char *qtype;
+
+	switch (qh->type) {
+	case USB_ENDPOINT_XFER_ISOC: qtype = "ISO"; break;
+	case USB_ENDPOINT_XFER_INT: qtype = "INT"; break;
+	case USB_ENDPOINT_XFER_BULK: qtype = "BLK"; break;
+	case USB_ENDPOINT_XFER_CONTROL: qtype = "CTL"; break;
+	default: qtype = "Skel" ; break;
+	}
+
+	out += sprintf(out, "%*s[%p] %s QH link (%08x) element (%08x)\n",
+			space, "", qh, qtype,
+			hc32_to_cpu(uhci, qh->link),
+			hc32_to_cpu(uhci, element));
+	if (qh->type == USB_ENDPOINT_XFER_ISOC)
+		out += sprintf(out,
+				"%*s    period %d phase %d load %d us, frame %x desc [%p]\n",
+				space, "", qh->period, qh->phase, qh->load,
+				qh->iso_frame, qh->iso_packet_desc);
+	else if (qh->type == USB_ENDPOINT_XFER_INT)
+		out += sprintf(out, "%*s    period %d phase %d load %d us\n",
+				space, "", qh->period, qh->phase, qh->load);
+	if (out - buf > len)
+		goto done;
+
+	if (element & UHCI_PTR_QH(uhci))
+		out += sprintf(out, "%*s  Element points to QH (bug?)\n", space, "");
+
+	if (element & UHCI_PTR_DEPTH(uhci))
+		out += sprintf(out, "%*s  Depth traverse\n", space, "");
+
+	if (element & cpu_to_hc32(uhci, 8))
+		out += sprintf(out, "%*s  Bit 3 set (bug?)\n", space, "");
+
+	if (!(element & ~(UHCI_PTR_QH(uhci) | UHCI_PTR_DEPTH(uhci))))
+		out += sprintf(out, "%*s  Element is NULL (bug?)\n", space, "");
+
+	if (out - buf > len)
+		goto done;
+
+	if (list_empty(&qh->queue)) {
+		out += sprintf(out, "%*s  queue is empty\n", space, "");
+		if (qh == uhci->skel_async_qh) {
+			out += uhci_show_td(uhci, uhci->term_td, out,
+					len - (out - buf), 0);
+			if (out - buf > len)
+				goto tail;
+		}
+	} else {
+		struct urb_priv *urbp = list_entry(qh->queue.next,
+				struct urb_priv, node);
+		struct uhci_td *td = list_entry(urbp->td_list.next,
+				struct uhci_td, list);
+
+		if (element != LINK_TO_TD(uhci, td))
+			out += sprintf(out, "%*s Element != First TD\n",
+					space, "");
+		i = nurbs = 0;
+		list_for_each_entry(urbp, &qh->queue, node) {
+			if (++i <= 10) {
+				out += uhci_show_urbp(uhci, urbp, out,
+						len - (out - buf), space + 2);
+				if (out - buf > len)
+					goto tail;
+			}
+			else
+				++nurbs;
+		}
+		if (nurbs > 0)
+			out += sprintf(out, "%*s Skipped %d URBs\n",
+					space, "", nurbs);
+	}
+
+	if (out - buf > len)
+		goto done;
+
+	if (qh->dummy_td) {
+		out += sprintf(out, "%*s  Dummy TD\n", space, "");
+		out += uhci_show_td(uhci, qh->dummy_td, out,
+				len - (out - buf), 0);
+		if (out - buf > len)
+			goto tail;
+	}
+
+done:
+	if (out - buf > len)
+		out += sprintf(out, " ...\n");
+tail:
+	return out - buf;
+}
+
+static int uhci_show_sc(int port, unsigned short status, char *buf)
+{
+	return sprintf(buf, "  stat%d     =     %04x  %s%s%s%s%s%s%s%s%s%s\n",
+		port,
+		status,
+		(status & USBPORTSC_SUSP) ?	" Suspend" : "",
+		(status & USBPORTSC_OCC) ?	" OverCurrentChange" : "",
+		(status & USBPORTSC_OC) ?	" OverCurrent" : "",
+		(status & USBPORTSC_PR) ?	" Reset" : "",
+		(status & USBPORTSC_LSDA) ?	" LowSpeed" : "",
+		(status & USBPORTSC_RD) ?	" ResumeDetect" : "",
+		(status & USBPORTSC_PEC) ?	" EnableChange" : "",
+		(status & USBPORTSC_PE) ?	" Enabled" : "",
+		(status & USBPORTSC_CSC) ?	" ConnectChange" : "",
+		(status & USBPORTSC_CCS) ?	" Connected" : "");
+}
+
+static int uhci_show_root_hub_state(struct uhci_hcd *uhci, char *buf)
+{
+	char *rh_state;
+
+	switch (uhci->rh_state) {
+	    case UHCI_RH_RESET:
+		rh_state = "reset";		break;
+	    case UHCI_RH_SUSPENDED:
+		rh_state = "suspended";		break;
+	    case UHCI_RH_AUTO_STOPPED:
+		rh_state = "auto-stopped";	break;
+	    case UHCI_RH_RESUMING:
+		rh_state = "resuming";		break;
+	    case UHCI_RH_SUSPENDING:
+		rh_state = "suspending";	break;
+	    case UHCI_RH_RUNNING:
+		rh_state = "running";		break;
+	    case UHCI_RH_RUNNING_NODEVS:
+		rh_state = "running, no devs";	break;
+	    default:
+		rh_state = "?";			break;
+	}
+	return sprintf(buf, "Root-hub state: %s   FSBR: %d\n",
+			rh_state, uhci->fsbr_is_on);
+}
+
+static int uhci_show_status(struct uhci_hcd *uhci, char *buf, int len)
+{
+	char *out = buf;
+	unsigned short usbcmd, usbstat, usbint, usbfrnum;
+	unsigned int flbaseadd;
+	unsigned char sof;
+	unsigned short portsc1, portsc2;
+
+
+	usbcmd    = uhci_readw(uhci, USBCMD);
+	usbstat   = uhci_readw(uhci, USBSTS);
+	usbint    = uhci_readw(uhci, USBINTR);
+	usbfrnum  = uhci_readw(uhci, USBFRNUM);
+	flbaseadd = uhci_readl(uhci, USBFLBASEADD);
+	sof       = uhci_readb(uhci, USBSOF);
+	portsc1   = uhci_readw(uhci, USBPORTSC1);
+	portsc2   = uhci_readw(uhci, USBPORTSC2);
+
+	out += sprintf(out, "  usbcmd    =     %04x   %s%s%s%s%s%s%s%s\n",
+		usbcmd,
+		(usbcmd & USBCMD_MAXP) ?    "Maxp64 " : "Maxp32 ",
+		(usbcmd & USBCMD_CF) ?      "CF " : "",
+		(usbcmd & USBCMD_SWDBG) ?   "SWDBG " : "",
+		(usbcmd & USBCMD_FGR) ?     "FGR " : "",
+		(usbcmd & USBCMD_EGSM) ?    "EGSM " : "",
+		(usbcmd & USBCMD_GRESET) ?  "GRESET " : "",
+		(usbcmd & USBCMD_HCRESET) ? "HCRESET " : "",
+		(usbcmd & USBCMD_RS) ?      "RS " : "");
+	if (out - buf > len)
+		goto done;
+
+	out += sprintf(out, "  usbstat   =     %04x   %s%s%s%s%s%s\n",
+		usbstat,
+		(usbstat & USBSTS_HCH) ?    "HCHalted " : "",
+		(usbstat & USBSTS_HCPE) ?   "HostControllerProcessError " : "",
+		(usbstat & USBSTS_HSE) ?    "HostSystemError " : "",
+		(usbstat & USBSTS_RD) ?     "ResumeDetect " : "",
+		(usbstat & USBSTS_ERROR) ?  "USBError " : "",
+		(usbstat & USBSTS_USBINT) ? "USBINT " : "");
+	if (out - buf > len)
+		goto done;
+
+	out += sprintf(out, "  usbint    =     %04x\n", usbint);
+	out += sprintf(out, "  usbfrnum  =   (%d)%03x\n", (usbfrnum >> 10) & 1,
+		0xfff & (4*(unsigned int)usbfrnum));
+	out += sprintf(out, "  flbaseadd = %08x\n", flbaseadd);
+	out += sprintf(out, "  sof       =       %02x\n", sof);
+	if (out - buf > len)
+		goto done;
+
+	out += uhci_show_sc(1, portsc1, out);
+	if (out - buf > len)
+		goto done;
+
+	out += uhci_show_sc(2, portsc2, out);
+	if (out - buf > len)
+		goto done;
+
+	out += sprintf(out,
+			"Most recent frame: %x (%d)   Last ISO frame: %x (%d)\n",
+			uhci->frame_number, uhci->frame_number & 1023,
+			uhci->last_iso_frame, uhci->last_iso_frame & 1023);
+
+done:
+	if (out - buf > len)
+		out += sprintf(out, " ...\n");
+	return out - buf;
+}
+
+static int uhci_sprint_schedule(struct uhci_hcd *uhci, char *buf, int len)
+{
+	char *out = buf;
+	int i, j;
+	struct uhci_qh *qh;
+	struct uhci_td *td;
+	struct list_head *tmp, *head;
+	int nframes, nerrs;
+	__hc32 link;
+	__hc32 fsbr_link;
+
+	static const char * const qh_names[] = {
+		"unlink", "iso", "int128", "int64", "int32", "int16",
+		"int8", "int4", "int2", "async", "term"
+	};
+
+	out += uhci_show_root_hub_state(uhci, out);
+	if (out - buf > len)
+		goto done;
+	out += sprintf(out, "HC status\n");
+	out += uhci_show_status(uhci, out, len - (out - buf));
+	if (out - buf > len)
+		goto tail;
+
+	out += sprintf(out, "Periodic load table\n");
+	for (i = 0; i < MAX_PHASE; ++i) {
+		out += sprintf(out, "\t%d", uhci->load[i]);
+		if (i % 8 == 7)
+			*out++ = '\n';
+	}
+	out += sprintf(out, "Total: %d, #INT: %d, #ISO: %d\n",
+			uhci->total_load,
+			uhci_to_hcd(uhci)->self.bandwidth_int_reqs,
+			uhci_to_hcd(uhci)->self.bandwidth_isoc_reqs);
+	if (debug <= 1)
+		goto tail;
+
+	out += sprintf(out, "Frame List\n");
+	nframes = 10;
+	nerrs = 0;
+	for (i = 0; i < UHCI_NUMFRAMES; ++i) {
+		__hc32 qh_dma;
+
+		if (out - buf > len)
+			goto done;
+		j = 0;
+		td = uhci->frame_cpu[i];
+		link = uhci->frame[i];
+		if (!td)
+			goto check_link;
+
+		if (nframes > 0) {
+			out += sprintf(out, "- Frame %d -> (%08x)\n",
+					i, hc32_to_cpu(uhci, link));
+			j = 1;
+		}
+
+		head = &td->fl_list;
+		tmp = head;
+		do {
+			td = list_entry(tmp, struct uhci_td, fl_list);
+			tmp = tmp->next;
+			if (link != LINK_TO_TD(uhci, td)) {
+				if (nframes > 0) {
+					out += sprintf(out,
+						"    link does not match list entry!\n");
+					if (out - buf > len)
+						goto done;
+				} else
+					++nerrs;
+			}
+			if (nframes > 0) {
+				out += uhci_show_td(uhci, td, out,
+						len - (out - buf), 4);
+				if (out - buf > len)
+					goto tail;
+			}
+			link = td->link;
+		} while (tmp != head);
+
+check_link:
+		qh_dma = uhci_frame_skel_link(uhci, i);
+		if (link != qh_dma) {
+			if (nframes > 0) {
+				if (!j) {
+					out += sprintf(out,
+						"- Frame %d -> (%08x)\n",
+						i, hc32_to_cpu(uhci, link));
+					j = 1;
+				}
+				out += sprintf(out,
+					"   link does not match QH (%08x)!\n",
+					hc32_to_cpu(uhci, qh_dma));
+				if (out - buf > len)
+					goto done;
+			} else
+				++nerrs;
+		}
+		nframes -= j;
+	}
+	if (nerrs > 0)
+		out += sprintf(out, "Skipped %d bad links\n", nerrs);
+
+	out += sprintf(out, "Skeleton QHs\n");
+
+	if (out - buf > len)
+		goto done;
+
+	fsbr_link = 0;
+	for (i = 0; i < UHCI_NUM_SKELQH; ++i) {
+		int cnt = 0;
+
+		qh = uhci->skelqh[i];
+		out += sprintf(out, "- skel_%s_qh\n", qh_names[i]);
+		out += uhci_show_qh(uhci, qh, out, len - (out - buf), 4);
+		if (out - buf > len)
+			goto tail;
+
+		/* Last QH is the Terminating QH, it's different */
+		if (i == SKEL_TERM) {
+			if (qh_element(qh) != LINK_TO_TD(uhci, uhci->term_td)) {
+				out += sprintf(out,
+					"    skel_term_qh element is not set to term_td!\n");
+				if (out - buf > len)
+					goto done;
+			}
+			link = fsbr_link;
+			if (!link)
+				link = LINK_TO_QH(uhci, uhci->skel_term_qh);
+			goto check_qh_link;
+		}
+
+		head = &qh->node;
+		tmp = head->next;
+
+		while (tmp != head) {
+			qh = list_entry(tmp, struct uhci_qh, node);
+			tmp = tmp->next;
+			if (++cnt <= 10) {
+				out += uhci_show_qh(uhci, qh, out,
+						len - (out - buf), 4);
+				if (out - buf > len)
+					goto tail;
+			}
+			if (!fsbr_link && qh->skel >= SKEL_FSBR)
+				fsbr_link = LINK_TO_QH(uhci, qh);
+		}
+		if ((cnt -= 10) > 0)
+			out += sprintf(out, "    Skipped %d QHs\n", cnt);
+
+		link = UHCI_PTR_TERM(uhci);
+		if (i <= SKEL_ISO)
+			;
+		else if (i < SKEL_ASYNC)
+			link = LINK_TO_QH(uhci, uhci->skel_async_qh);
+		else if (!uhci->fsbr_is_on)
+			;
+		else
+			link = LINK_TO_QH(uhci, uhci->skel_term_qh);
+check_qh_link:
+		if (qh->link != link)
+			out += sprintf(out,
+				"    last QH not linked to next skeleton!\n");
+
+		if (out - buf > len)
+			goto done;
+	}
+
+done:
+	if (out - buf > len)
+		out += sprintf(out, " ...\n");
+tail:
+	return out - buf;
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+#define MAX_OUTPUT	(64 * 1024)
+
+struct uhci_debug {
+	int size;
+	char *data;
+};
+
+static int uhci_debug_open(struct inode *inode, struct file *file)
+{
+	struct uhci_hcd *uhci = inode->i_private;
+	struct uhci_debug *up;
+	unsigned long flags;
+
+	up = kmalloc_obj(*up);
+	if (!up)
+		return -ENOMEM;
+
+	up->data = kmalloc(MAX_OUTPUT, GFP_KERNEL);
+	if (!up->data) {
+		kfree(up);
+		return -ENOMEM;
+	}
+
+	up->size = 0;
+	spin_lock_irqsave(&uhci->lock, flags);
+	if (uhci->is_initialized)
+		up->size = uhci_sprint_schedule(uhci, up->data,
+					MAX_OUTPUT - EXTRA_SPACE);
+	spin_unlock_irqrestore(&uhci->lock, flags);
+
+	file->private_data = up;
+
+	return 0;
+}
+
+static loff_t uhci_debug_lseek(struct file *file, loff_t off, int whence)
+{
+	struct uhci_debug *up = file->private_data;
+	return no_seek_end_llseek_size(file, off, whence, up->size);
+}
+
+static ssize_t uhci_debug_read(struct file *file, char __user *buf,
+				size_t nbytes, loff_t *ppos)
+{
+	struct uhci_debug *up = file->private_data;
+	return simple_read_from_buffer(buf, nbytes, ppos, up->data, up->size);
+}
+
+static int uhci_debug_release(struct inode *inode, struct file *file)
+{
+	struct uhci_debug *up = file->private_data;
+
+	kfree(up->data);
+	kfree(up);
+
+	return 0;
+}
+
+static const struct file_operations uhci_debug_operations = {
+	.owner =	THIS_MODULE,
+	.open =		uhci_debug_open,
+	.llseek =	uhci_debug_lseek,
+	.read =		uhci_debug_read,
+	.release =	uhci_debug_release,
+};
+#define UHCI_DEBUG_OPS
+
+#endif	/* CONFIG_DEBUG_FS */
+
+#else	/* CONFIG_DYNAMIC_DEBUG*/
+
+static inline void lprintk(char *buf)
+{}
+
+static inline int uhci_show_qh(struct uhci_hcd *uhci,
+		struct uhci_qh *qh, char *buf, int len, int space)
+{
+	return 0;
+}
+
+static inline int uhci_sprint_schedule(struct uhci_hcd *uhci,
+		char *buf, int len)
+{
+	return 0;
+}
+
+#endif