[mirror_ubuntu-artful-kernel.git] / arch / um / kernel / trap.c

/*
 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL
 */

#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/hardirq.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <asm/current.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <arch.h>
#include <as-layout.h>
#include <kern_util.h>
#include <os.h>
#include <skas.h>

/*
 * Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by
 * segv().
 */
int handle_page_fault(unsigned long address, unsigned long ip,
		      int is_write, int is_user, int *code_out)
{
	struct mm_struct *mm = current->mm;
	struct vm_area_struct *vma;
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;
	int err = -EFAULT;
	unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;

	*code_out = SEGV_MAPERR;

	/*
	 * If the fault was with pagefaults disabled, don't take the fault, just
	 * fail.
	 */
	if (faulthandler_disabled())
		goto out_nosemaphore;

	if (is_user)
		flags |= FAULT_FLAG_USER;
retry:
	down_read(&mm->mmap_sem);
	vma = find_vma(mm, address);
	if (!vma)
		goto out;
	else if (vma->vm_start <= address)
		goto good_area;
	else if (!(vma->vm_flags & VM_GROWSDOWN))
		goto out;
	else if (is_user && !ARCH_IS_STACKGROW(address))
		goto out;
	else if (expand_stack(vma, address))
		goto out;

good_area:
	*code_out = SEGV_ACCERR;
	if (is_write) {
		if (!(vma->vm_flags & VM_WRITE))
			goto out;
		flags |= FAULT_FLAG_WRITE;
	} else {
		/* Don't require VM_READ|VM_EXEC for write faults! */
		if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
			goto out;
	}

	do {
		int fault;

		fault = handle_mm_fault(vma, address, flags);

		if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
			goto out_nosemaphore;

		if (unlikely(fault & VM_FAULT_ERROR)) {
			if (fault & VM_FAULT_OOM) {
				goto out_of_memory;
			} else if (fault & VM_FAULT_SIGSEGV) {
				goto out;
			} else if (fault & VM_FAULT_SIGBUS) {
				err = -EACCES;
				goto out;
			}
			BUG();
		}
		if (flags & FAULT_FLAG_ALLOW_RETRY) {
			if (fault & VM_FAULT_MAJOR)
				current->maj_flt++;
			else
				current->min_flt++;
			if (fault & VM_FAULT_RETRY) {
				flags &= ~FAULT_FLAG_ALLOW_RETRY;
				flags |= FAULT_FLAG_TRIED;

				goto retry;
			}
		}

		pgd = pgd_offset(mm, address);
		pud = pud_offset(pgd, address);
		pmd = pmd_offset(pud, address);
		pte = pte_offset_kernel(pmd, address);
	} while (!pte_present(*pte));
	err = 0;
	/*
	 * The below warning was added in place of
	 *	pte_mkyoung(); if (is_write) pte_mkdirty();
	 * If it's triggered, we'd see normally a hang here (a clean pte is
	 * marked read-only to emulate the dirty bit).
	 * However, the generic code can mark a PTE writable but clean on a
	 * concurrent read fault, triggering this harmlessly. So comment it out.
	 */
#if 0
	WARN_ON(!pte_young(*pte) || (is_write && !pte_dirty(*pte)));
#endif
	flush_tlb_page(vma, address);
out:
	up_read(&mm->mmap_sem);
out_nosemaphore:
	return err;

out_of_memory:
	/*
	 * We ran out of memory, call the OOM killer, and return the userspace
	 * (which will retry the fault, or kill us if we got oom-killed).
	 */
	up_read(&mm->mmap_sem);
	if (!is_user)
		goto out_nosemaphore;
	pagefault_out_of_memory();
	return 0;
}
EXPORT_SYMBOL(handle_page_fault);

static void show_segv_info(struct uml_pt_regs *regs)
{
	struct task_struct *tsk = current;
	struct faultinfo *fi = UPT_FAULTINFO(regs);

	if (!unhandled_signal(tsk, SIGSEGV))
		return;

	if (!printk_ratelimit())
		return;

	printk("%s%s[%d]: segfault at %lx ip %p sp %p error %x",
		task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
		tsk->comm, task_pid_nr(tsk), FAULT_ADDRESS(*fi),
		(void *)UPT_IP(regs), (void *)UPT_SP(regs),
		fi->error_code);

	print_vma_addr(KERN_CONT " in ", UPT_IP(regs));
	printk(KERN_CONT "\n");
}

static void bad_segv(struct faultinfo fi, unsigned long ip)
{
	struct siginfo si;

	si.si_signo = SIGSEGV;
	si.si_code = SEGV_ACCERR;
	si.si_addr = (void __user *) FAULT_ADDRESS(fi);
	current->thread.arch.faultinfo = fi;
	force_sig_info(SIGSEGV, &si, current);
}

void fatal_sigsegv(void)
{
	force_sigsegv(SIGSEGV, current);
	do_signal(&current->thread.regs);
	/*
	 * This is to tell gcc that we're not returning - do_signal
	 * can, in general, return, but in this case, it's not, since
	 * we just got a fatal SIGSEGV queued.
	 */
	os_dump_core();
}

void segv_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
{
	struct faultinfo * fi = UPT_FAULTINFO(regs);

	if (UPT_IS_USER(regs) && !SEGV_IS_FIXABLE(fi)) {
		show_segv_info(regs);
		bad_segv(*fi, UPT_IP(regs));
		return;
	}
	segv(*fi, UPT_IP(regs), UPT_IS_USER(regs), regs);
}

/*
 * We give a *copy* of the faultinfo in the regs to segv.
 * This must be done, since nesting SEGVs could overwrite
 * the info in the regs. A pointer to the info then would
 * give us bad data!
 */
unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
		   struct uml_pt_regs *regs)
{
	struct siginfo si;
	jmp_buf *catcher;
	int err;
	int is_write = FAULT_WRITE(fi);
	unsigned long address = FAULT_ADDRESS(fi);

	if (!is_user && regs)
		current->thread.segv_regs = container_of(regs, struct pt_regs, regs);

	if (!is_user && (address >= start_vm) && (address < end_vm)) {
		flush_tlb_kernel_vm();
		goto out;
	}
	else if (current->mm == NULL) {
		show_regs(container_of(regs, struct pt_regs, regs));
		panic("Segfault with no mm");
	}
	else if (!is_user && address > PAGE_SIZE && address < TASK_SIZE) {
		show_regs(container_of(regs, struct pt_regs, regs));
		panic("Kernel tried to access user memory at addr 0x%lx, ip 0x%lx",
		       address, ip);
	}

	if (SEGV_IS_FIXABLE(&fi))
		err = handle_page_fault(address, ip, is_write, is_user,
					&si.si_code);
	else {
		err = -EFAULT;
		/*
		 * A thread accessed NULL, we get a fault, but CR2 is invalid.
		 * This code is used in __do_copy_from_user() of TT mode.
		 * XXX tt mode is gone, so maybe this isn't needed any more
		 */
		address = 0;
	}

	catcher = current->thread.fault_catcher;
	if (!err)
		goto out;
	else if (catcher != NULL) {
		current->thread.fault_addr = (void *) address;
		UML_LONGJMP(catcher, 1);
	}
	else if (current->thread.fault_addr != NULL)
		panic("fault_addr set but no fault catcher");
	else if (!is_user && arch_fixup(ip, regs))
		goto out;

	if (!is_user) {
		show_regs(container_of(regs, struct pt_regs, regs));
		panic("Kernel mode fault at addr 0x%lx, ip 0x%lx",
		      address, ip);
	}

	show_segv_info(regs);

	if (err == -EACCES) {
		si.si_signo = SIGBUS;
		si.si_errno = 0;
		si.si_code = BUS_ADRERR;
		si.si_addr = (void __user *)address;
		current->thread.arch.faultinfo = fi;
		force_sig_info(SIGBUS, &si, current);
	} else {
		BUG_ON(err != -EFAULT);
		si.si_signo = SIGSEGV;
		si.si_addr = (void __user *) address;
		current->thread.arch.faultinfo = fi;
		force_sig_info(SIGSEGV, &si, current);
	}

out:
	if (regs)
		current->thread.segv_regs = NULL;

	return 0;
}

void relay_signal(int sig, struct siginfo *si, struct uml_pt_regs *regs)
{
	struct faultinfo *fi;
	struct siginfo clean_si;

	if (!UPT_IS_USER(regs)) {
		if (sig == SIGBUS)
			printk(KERN_ERR "Bus error - the host /dev/shm or /tmp "
			       "mount likely just ran out of space\n");
		panic("Kernel mode signal %d", sig);
	}

	arch_examine_signal(sig, regs);

	memset(&clean_si, 0, sizeof(clean_si));
	clean_si.si_signo = si->si_signo;
	clean_si.si_errno = si->si_errno;
	clean_si.si_code = si->si_code;
	switch (sig) {
	case SIGILL:
	case SIGFPE:
	case SIGSEGV:
	case SIGBUS:
	case SIGTRAP:
		fi = UPT_FAULTINFO(regs);
		clean_si.si_addr = (void __user *) FAULT_ADDRESS(*fi);
		current->thread.arch.faultinfo = *fi;
#ifdef __ARCH_SI_TRAPNO
		clean_si.si_trapno = si->si_trapno;
#endif
		break;
	default:
		printk(KERN_ERR "Attempted to relay unknown signal %d (si_code = %d)\n",
			sig, si->si_code);
	}

	force_sig_info(sig, &clean_si, current);
}

void bus_handler(int sig, struct siginfo *si, struct uml_pt_regs *regs)
{
	if (current->thread.fault_catcher != NULL)
		UML_LONGJMP(current->thread.fault_catcher, 1);
	else
		relay_signal(sig, si, regs);
}

void winch(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
{
	do_IRQ(WINCH_IRQ, regs);
}

void trap_init(void)
{
}
Commit	Line	Data
ea2ba7dc	1	/*
4c9e1385	2	* Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
1da177e4 LT	3	* Licensed under the GPL
	4	*/
	5
4c9e1385 JD	6	#include <linux/mm.h>
	7	#include <linux/sched.h>
	8	#include <linux/hardirq.h>
73395a00	9	#include <linux/module.h>
fbc9f16a	10	#include <linux/uaccess.h>
4c9e1385 JD	11	#include <asm/current.h>
	12	#include <asm/pgtable.h>
	13	#include <asm/tlbflush.h>
37185b33 AV	14	#include <arch.h>
	15	#include <as-layout.h>
	16	#include <kern_util.h>
	17	#include <os.h>
	18	#include <skas.h>
1da177e4	19
4c9e1385 JD	20	/*
	21	* Note this is constrained to return 0, -EFAULT, -EACCESS, -ENOMEM by
	22	* segv().
	23	*/
1d3468a6	24	int handle_page_fault(unsigned long address, unsigned long ip,
1da177e4 LT	25	int is_write, int is_user, int *code_out)
	26	{
	27	struct mm_struct *mm = current->mm;
	28	struct vm_area_struct *vma;
	29	pgd_t *pgd;
	30	pud_t *pud;
	31	pmd_t *pmd;
	32	pte_t *pte;
1da177e4	33	int err = -EFAULT;
759496ba	34	unsigned int flags = FAULT_FLAG_ALLOW_RETRY \| FAULT_FLAG_KILLABLE;
1da177e4 LT	35
1da177e4 LT	36	*code_out = SEGV_MAPERR;
fea03cb4	37
4c9e1385	38	/*
70ffdb93	39	* If the fault was with pagefaults disabled, don't take the fault, just
4c9e1385 JD	40	* fail.
4c9e1385 JD	41	*/
70ffdb93	42	if (faulthandler_disabled())
fea03cb4 PBG	43	goto out_nosemaphore;
fea03cb4 PBG	44
759496ba JW	45	if (is_user)
759496ba JW	46	flags \|= FAULT_FLAG_USER;
1cefe28f	47	retry:
1da177e4 LT	48	down_read(&mm->mmap_sem);
1da177e4 LT	49	vma = find_vma(mm, address);
4c9e1385	50	if (!vma)
1da177e4	51	goto out;
4c9e1385	52	else if (vma->vm_start <= address)
1da177e4	53	goto good_area;
4c9e1385	54	else if (!(vma->vm_flags & VM_GROWSDOWN))
1da177e4	55	goto out;
4c9e1385	56	else if (is_user && !ARCH_IS_STACKGROW(address))
1da177e4	57	goto out;
4c9e1385	58	else if (expand_stack(vma, address))
1da177e4 LT	59	goto out;
1da177e4 LT	60
3b52166c	61	good_area:
1da177e4	62	*code_out = SEGV_ACCERR;
759496ba JW	63	if (is_write) {
	64	if (!(vma->vm_flags & VM_WRITE))
	65	goto out;
	66	flags \|= FAULT_FLAG_WRITE;
	67	} else {
	68	/* Don't require VM_READ\|VM_EXEC for write faults! */
	69	if (!(vma->vm_flags & (VM_READ \| VM_EXEC)))
	70	goto out;
	71	}
13479d52	72
1da177e4	73	do {
83c54070	74	int fault;
1c0fe6e3	75
dcddffd4	76	fault = handle_mm_fault(vma, address, flags);
1cefe28f KC	77
	78	if ((fault & VM_FAULT_RETRY) && fatal_signal_pending(current))
	79	goto out_nosemaphore;
	80
83c54070 NP	81	if (unlikely(fault & VM_FAULT_ERROR)) {
83c54070 NP	82	if (fault & VM_FAULT_OOM) {
83c54070	83	goto out_of_memory;
33692f27 LT	84	} else if (fault & VM_FAULT_SIGSEGV) {
33692f27 LT	85	goto out;
83c54070 NP	86	} else if (fault & VM_FAULT_SIGBUS) {
	87	err = -EACCES;
	88	goto out;
	89	}
1da177e4 LT	90	BUG();
1da177e4 LT	91	}
1cefe28f KC	92	if (flags & FAULT_FLAG_ALLOW_RETRY) {
	93	if (fault & VM_FAULT_MAJOR)
	94	current->maj_flt++;
	95	else
	96	current->min_flt++;
	97	if (fault & VM_FAULT_RETRY) {
	98	flags &= ~FAULT_FLAG_ALLOW_RETRY;
45cac65b	99	flags \|= FAULT_FLAG_TRIED;
1cefe28f KC	100
	101	goto retry;
	102	}
	103	}
83c54070	104
3b52166c PBG	105	pgd = pgd_offset(mm, address);
	106	pud = pud_offset(pgd, address);
	107	pmd = pmd_offset(pud, address);
	108	pte = pte_offset_kernel(pmd, address);
4c9e1385	109	} while (!pte_present(*pte));
1da177e4	110	err = 0;
4c9e1385 JD	111	/*
4c9e1385 JD	112	* The below warning was added in place of
cbc24afa PBG	113	* pte_mkyoung(); if (is_write) pte_mkdirty();
	114	* If it's triggered, we'd see normally a hang here (a clean pte is
	115	* marked read-only to emulate the dirty bit).
	116	* However, the generic code can mark a PTE writable but clean on a
	117	* concurrent read fault, triggering this harmlessly. So comment it out.
	118	*/
	119	#if 0
16b03678	120	WARN_ON(!pte_young(pte) \|\| (is_write && !pte_dirty(pte)));
cbc24afa	121	#endif
3b52166c PBG	122	flush_tlb_page(vma, address);
3b52166c PBG	123	out:
1da177e4	124	up_read(&mm->mmap_sem);
fea03cb4	125	out_nosemaphore:
4c9e1385	126	return err;
1da177e4	127
1da177e4	128	out_of_memory:
1c0fe6e3 NP	129	/*
	130	* We ran out of memory, call the OOM killer, and return the userspace
	131	* (which will retry the fault, or kill us if we got oom-killed).
	132	*/
	133	up_read(&mm->mmap_sem);
87134102 JW	134	if (!is_user)
87134102 JW	135	goto out_nosemaphore;
1c0fe6e3 NP	136	pagefault_out_of_memory();
1c0fe6e3 NP	137	return 0;
1da177e4	138	}
73395a00	139	EXPORT_SYMBOL(handle_page_fault);
1da177e4	140
3ef6130a RW	141	static void show_segv_info(struct uml_pt_regs *regs)
	142	{
	143	struct task_struct *tsk = current;
	144	struct faultinfo *fi = UPT_FAULTINFO(regs);
	145
	146	if (!unhandled_signal(tsk, SIGSEGV))
	147	return;
	148
	149	if (!printk_ratelimit())
	150	return;
	151
	152	printk("%s%s[%d]: segfault at %lx ip %p sp %p error %x",
	153	task_pid_nr(tsk) > 1 ? KERN_INFO : KERN_EMERG,
	154	tsk->comm, task_pid_nr(tsk), FAULT_ADDRESS(*fi),
	155	(void )UPT_IP(regs), (void )UPT_SP(regs),
	156	fi->error_code);
	157
	158	print_vma_addr(KERN_CONT " in ", UPT_IP(regs));
	159	printk(KERN_CONT "\n");
	160	}
	161
27aa6ef3 JD	162	static void bad_segv(struct faultinfo fi, unsigned long ip)
	163	{
	164	struct siginfo si;
	165
	166	si.si_signo = SIGSEGV;
	167	si.si_code = SEGV_ACCERR;
	168	si.si_addr = (void __user *) FAULT_ADDRESS(fi);
	169	current->thread.arch.faultinfo = fi;
	170	force_sig_info(SIGSEGV, &si, current);
	171	}
	172
3e6f2ac4 JD	173	void fatal_sigsegv(void)
	174	{
	175	force_sigsegv(SIGSEGV, current);
ccaee5f8	176	do_signal(&current->thread.regs);
3e6f2ac4 JD	177	/*
	178	* This is to tell gcc that we're not returning - do_signal
	179	* can, in general, return, but in this case, it's not, since
	180	* we just got a fatal SIGSEGV queued.
	181	*/
	182	os_dump_core();
	183	}
	184
d3c1cfcd	185	void segv_handler(int sig, struct siginfo unused_si, struct uml_pt_regs regs)
c66fdd5e GS	186	{
	187	struct faultinfo * fi = UPT_FAULTINFO(regs);
	188
4c9e1385	189	if (UPT_IS_USER(regs) && !SEGV_IS_FIXABLE(fi)) {
3ef6130a	190	show_segv_info(regs);
c66fdd5e GS	191	bad_segv(*fi, UPT_IP(regs));
	192	return;
	193	}
	194	segv(*fi, UPT_IP(regs), UPT_IS_USER(regs), regs);
	195	}
	196
c578455a BS	197	/*
	198	* We give a copy of the faultinfo in the regs to segv.
	199	* This must be done, since nesting SEGVs could overwrite
	200	* the info in the regs. A pointer to the info then would
	201	* give us bad data!
	202	*/
5d86456d	203	unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
77bf4400	204	struct uml_pt_regs *regs)
1da177e4 LT	205	{
1da177e4 LT	206	struct siginfo si;
fab95c55	207	jmp_buf *catcher;
1da177e4	208	int err;
5d86456d JD	209	int is_write = FAULT_WRITE(fi);
5d86456d JD	210	unsigned long address = FAULT_ADDRESS(fi);
1da177e4	211
bb6a1b2e	212	if (!is_user && regs)
f72c22e4 RW	213	current->thread.segv_regs = container_of(regs, struct pt_regs, regs);
f72c22e4 RW	214
4c9e1385	215	if (!is_user && (address >= start_vm) && (address < end_vm)) {
5d86456d	216	flush_tlb_kernel_vm();
f72c22e4	217	goto out;
5d86456d	218	}
4c9e1385	219	else if (current->mm == NULL) {
377fad3a	220	show_regs(container_of(regs, struct pt_regs, regs));
4c9e1385	221	panic("Segfault with no mm");
377fad3a	222	}
56b88a3b	223	else if (!is_user && address > PAGE_SIZE && address < TASK_SIZE) {
d2313084 RW	224	show_regs(container_of(regs, struct pt_regs, regs));
	225	panic("Kernel tried to access user memory at addr 0x%lx, ip 0x%lx",
	226	address, ip);
	227	}
546fe1cb	228
d0b5e15f	229	if (SEGV_IS_FIXABLE(&fi))
4c9e1385 JD	230	err = handle_page_fault(address, ip, is_write, is_user,
4c9e1385 JD	231	&si.si_code);
546fe1cb PBG	232	else {
546fe1cb PBG	233	err = -EFAULT;
4c9e1385 JD	234	/*
	235	* A thread accessed NULL, we get a fault, but CR2 is invalid.
	236	* This code is used in __do_copy_from_user() of TT mode.
	237	* XXX tt mode is gone, so maybe this isn't needed any more
	238	*/
546fe1cb PBG	239	address = 0;
546fe1cb PBG	240	}
1da177e4 LT	241
1da177e4 LT	242	catcher = current->thread.fault_catcher;
4c9e1385	243	if (!err)
f72c22e4	244	goto out;
4c9e1385	245	else if (catcher != NULL) {
1da177e4	246	current->thread.fault_addr = (void *) address;
fab95c55	247	UML_LONGJMP(catcher, 1);
1d3468a6	248	}
4c9e1385	249	else if (current->thread.fault_addr != NULL)
1da177e4	250	panic("fault_addr set but no fault catcher");
4c9e1385	251	else if (!is_user && arch_fixup(ip, regs))
f72c22e4	252	goto out;
1da177e4	253
4c9e1385	254	if (!is_user) {
377fad3a	255	show_regs(container_of(regs, struct pt_regs, regs));
1d3468a6	256	panic("Kernel mode fault at addr 0x%lx, ip 0x%lx",
1da177e4	257	address, ip);
377fad3a	258	}
1da177e4	259
3ef6130a RW	260	show_segv_info(regs);
3ef6130a RW	261
3b52166c	262	if (err == -EACCES) {
1da177e4 LT	263	si.si_signo = SIGBUS;
	264	si.si_errno = 0;
	265	si.si_code = BUS_ADRERR;
4d338e1a	266	si.si_addr = (void __user *)address;
5d86456d	267	current->thread.arch.faultinfo = fi;
1da177e4	268	force_sig_info(SIGBUS, &si, current);
3b52166c PBG	269	} else {
3b52166c PBG	270	BUG_ON(err != -EFAULT);
1da177e4	271	si.si_signo = SIGSEGV;
4d338e1a	272	si.si_addr = (void __user *) address;
5d86456d	273	current->thread.arch.faultinfo = fi;
1da177e4 LT	274	force_sig_info(SIGSEGV, &si, current);
1da177e4 LT	275	}
f72c22e4 RW	276
	277	out:
	278	if (regs)
	279	current->thread.segv_regs = NULL;
	280
5d86456d	281	return 0;
1da177e4 LT	282	}
1da177e4 LT	283
d3c1cfcd	284	void relay_signal(int sig, struct siginfo si, struct uml_pt_regs regs)
1da177e4	285	{
d3c1cfcd MP	286	struct faultinfo *fi;
	287	struct siginfo clean_si;
	288
4c9e1385 JD	289	if (!UPT_IS_USER(regs)) {
	290	if (sig == SIGBUS)
	291	printk(KERN_ERR "Bus error - the host /dev/shm or /tmp "
	292	"mount likely just ran out of space\n");
1da177e4	293	panic("Kernel mode signal %d", sig);
6edf428e JD	294	}
6edf428e JD	295
9226b838 JD	296	arch_examine_signal(sig, regs);
9226b838 JD	297
d3c1cfcd MP	298	memset(&clean_si, 0, sizeof(clean_si));
	299	clean_si.si_signo = si->si_signo;
	300	clean_si.si_errno = si->si_errno;
	301	clean_si.si_code = si->si_code;
	302	switch (sig) {
	303	case SIGILL:
	304	case SIGFPE:
	305	case SIGSEGV:
	306	case SIGBUS:
	307	case SIGTRAP:
	308	fi = UPT_FAULTINFO(regs);
	309	clean_si.si_addr = (void __user ) FAULT_ADDRESS(fi);
	310	current->thread.arch.faultinfo = *fi;
	311	#ifdef __ARCH_SI_TRAPNO
	312	clean_si.si_trapno = si->si_trapno;
	313	#endif
	314	break;
	315	default:
	316	printk(KERN_ERR "Attempted to relay unknown signal %d (si_code = %d)\n",
	317	sig, si->si_code);
	318	}
	319
	320	force_sig_info(sig, &clean_si, current);
1da177e4 LT	321	}
1da177e4 LT	322
d3c1cfcd	323	void bus_handler(int sig, struct siginfo si, struct uml_pt_regs regs)
1da177e4	324	{
4c9e1385	325	if (current->thread.fault_catcher != NULL)
fab95c55	326	UML_LONGJMP(current->thread.fault_catcher, 1);
d3c1cfcd MP	327	else
d3c1cfcd MP	328	relay_signal(sig, si, regs);
1da177e4 LT	329	}
1da177e4 LT	330
d3c1cfcd	331	void winch(int sig, struct siginfo unused_si, struct uml_pt_regs regs)
1da177e4 LT	332	{
	333	do_IRQ(WINCH_IRQ, regs);
	334	}
	335
	336	void trap_init(void)
	337	{
	338	}