/*
 * NOTE: This example is works on x86 and powerpc.
 * Here's a sample kernel module showing the use of kprobes to dump a
 * stack trace and selected registers when _do_fork() is called.
 *
 * For more information on theory of operation of kprobes, see
 * Documentation/kprobes.txt
 *
 * You will see the trace data in /var/log/messages and on the console
 * whenever _do_fork() is invoked to create a new process.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/kprobes.h>

#define MAX_SYMBOL_LEN	64
static char symbol[MAX_SYMBOL_LEN] = "_do_fork";
module_param_string(symbol, symbol, sizeof(symbol), 0644);

/* For each probe you need to allocate a kprobe structure */
static struct kprobe kp = {
	.symbol_name	= symbol,
};

/* kprobe pre_handler: called just before the probed instruction is executed */
static int handler_pre(struct kprobe *p, struct pt_regs *regs)
{
#ifdef CONFIG_X86
	pr_info("<%s> pre_handler: p->addr = 0x%p, ip = %lx, flags = 0x%lx\n",
		p->symbol_name, p->addr, regs->ip, regs->flags);
#endif
#ifdef CONFIG_PPC
	pr_info("<%s> pre_handler: p->addr = 0x%p, nip = 0x%lx, msr = 0x%lx\n",
		p->symbol_name, p->addr, regs->nip, regs->msr);
#endif
#ifdef CONFIG_MIPS
	pr_info("<%s> pre_handler: p->addr = 0x%p, epc = 0x%lx, status = 0x%lx\n",
		p->symbol_name, p->addr, regs->cp0_epc, regs->cp0_status);
#endif
#ifdef CONFIG_TILEGX
	pr_info("<%s> pre_handler: p->addr = 0x%p, pc = 0x%lx, ex1 = 0x%lx\n",
		p->symbol_name, p->addr, regs->pc, regs->ex1);
#endif
#ifdef CONFIG_ARM64
	pr_info("<%s> pre_handler: p->addr = 0x%p, pc = 0x%lx,"
			" pstate = 0x%lx\n",
		p->symbol_name, p->addr, (long)regs->pc, (long)regs->pstate);
#endif

	/* A dump_stack() here will give a stack backtrace */
	return 0;
}

/* kprobe post_handler: called after the probed instruction is executed */
static void handler_post(struct kprobe *p, struct pt_regs *regs,
				unsigned long flags)
{
#ifdef CONFIG_X86
	pr_info("<%s> post_handler: p->addr = 0x%p, flags = 0x%lx\n",
		p->symbol_name, p->addr, regs->flags);
#endif
#ifdef CONFIG_PPC
	pr_info("<%s> post_handler: p->addr = 0x%p, msr = 0x%lx\n",
		p->symbol_name, p->addr, regs->msr);
#endif
#ifdef CONFIG_MIPS
	pr_info("<%s> post_handler: p->addr = 0x%p, status = 0x%lx\n",
		p->symbol_name, p->addr, regs->cp0_status);
#endif
#ifdef CONFIG_TILEGX
	pr_info("<%s> post_handler: p->addr = 0x%p, ex1 = 0x%lx\n",
		p->symbol_name, p->addr, regs->ex1);
#endif
#ifdef CONFIG_ARM64
	pr_info("<%s> post_handler: p->addr = 0x%p, pstate = 0x%lx\n",
		p->symbol_name, p->addr, (long)regs->pstate);
#endif
}

/*
 * fault_handler: this is called if an exception is generated for any
 * instruction within the pre- or post-handler, or when Kprobes
 * single-steps the probed instruction.
 */
static int handler_fault(struct kprobe *p, struct pt_regs *regs, int trapnr)
{
	pr_info("fault_handler: p->addr = 0x%p, trap #%dn", p->addr, trapnr);
	/* Return 0 because we don't handle the fault. */
	return 0;
}

static int __init kprobe_init(void)
{
	int ret;
	kp.pre_handler = handler_pre;
	kp.post_handler = handler_post;
	kp.fault_handler = handler_fault;

	ret = register_kprobe(&kp);
	if (ret < 0) {
		pr_err("register_kprobe failed, returned %d\n", ret);
		return ret;
	}
	pr_info("Planted kprobe at %p\n", kp.addr);
	return 0;
}

static void __exit kprobe_exit(void)
{
	unregister_kprobe(&kp);
	pr_info("kprobe at %p unregistered\n", kp.addr);
}

module_init(kprobe_init)
module_exit(kprobe_exit)
MODULE_LICENSE("GPL");
ss='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='c14024dbb156c8392908aaa822097d27c6af8ec8'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Jens Axboe &lt;axboe@fb.com&gt;</td><td class='right'>2017-01-27 11:56:06 -0700</td></tr>
<tr><th>committer</th><td>Jens Axboe &lt;axboe@fb.com&gt;</td><td class='right'>2017-01-27 11:56:06 -0700</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/atm/signaling.c?h=nds-private-remove&amp;id=c14024dbb156c8392908aaa822097d27c6af8ec8'>c14024dbb156c8392908aaa822097d27c6af8ec8</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/atm/signaling.c?id=c14024dbb156c8392908aaa822097d27c6af8ec8'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=c14024dbb156c8392908aaa822097d27c6af8ec8'>02f6ffa664b16bd76750c05f62708a518de2acdc</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/atm/signaling.c?h=nds-private-remove&amp;id=c14024dbb156c8392908aaa822097d27c6af8ec8'>net/atm/signaling.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/atm/signaling.c?h=nds-private-remove&amp;id=08965c2eba135bdfb6e86cf25308e01421c7e0ce'>08965c2eba135bdfb6e86cf25308e01421c7e0ce</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/atm/signaling.c?h=nds-private-remove&amp;id=c14024dbb156c8392908aaa822097d27c6af8ec8&amp;id2=08965c2eba135bdfb6e86cf25308e01421c7e0ce'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/atm/signaling.c?h=nds-private-remove&amp;id=3b4f18843e511193e7eb616710e838f5852e661d'>3b4f18843e511193e7eb616710e838f5852e661d</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/atm/signaling.c?h=nds-private-remove&amp;id=c14024dbb156c8392908aaa822097d27c6af8ec8&amp;id2=3b4f18843e511193e7eb616710e838f5852e661d'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'stable/for-jens-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus</div><div class='commit-msg'>Konrad writes:

Please pull in your 'for-linus' branch two little fixes for Xen
block front:

One fix is for handling the XEN_PAGE_SIZE != PAGE_SIZE (4KB vs 64KB
on ARM for example) mishandling while the other is fixing
the accounting for the configuration changes.
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=c14024dbb156c8392908aaa822097d27c6af8ec8'>Diffstat</a> (limited to 'net/atm/signaling.c')</div><table summary='diffstat' class='diffstat'>