/* Inject a hwpoison memory failure on a arbitrary pfn */
#include <linux/module.h>
#include <linux/debugfs.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/pagemap.h>
#include <linux/hugetlb.h>
#include "internal.h"

static struct dentry *hwpoison_dir;

static int hwpoison_inject(void *data, u64 val)
{
	unsigned long pfn = val;
	struct page *p;
	struct page *hpage;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (!pfn_valid(pfn))
		return -ENXIO;

	p = pfn_to_page(pfn);
	hpage = compound_head(p);
	/*
	 * This implies unable to support free buddy pages.
	 */
	if (!get_hwpoison_page(p))
		return 0;

	if (!hwpoison_filter_enable)
		goto inject;

	if (!PageLRU(hpage) && !PageHuge(p))
		shake_page(hpage, 0);
	/*
	 * This implies unable to support non-LRU pages.
	 */
	if (!PageLRU(hpage) && !PageHuge(p))
		goto put_out;

	/*
	 * do a racy check with elevated page count, to make sure PG_hwpoison
	 * will only be set for the targeted owner (or on a free page).
	 * memory_failure() will redo the check reliably inside page lock.
	 */
	err = hwpoison_filter(hpage);
	if (err)
		goto put_out;

inject:
	pr_info("Injecting memory failure at pfn %#lx\n", pfn);
	return memory_failure(pfn, 18, MF_COUNT_INCREASED);
put_out:
	put_hwpoison_page(p);
	return 0;
}

static int hwpoison_unpoison(void *data, u64 val)
{
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	return unpoison_memory(val);
}

DEFINE_SIMPLE_ATTRIBUTE(hwpoison_fops, NULL, hwpoison_inject, "%lli\n");
DEFINE_SIMPLE_ATTRIBUTE(unpoison_fops, NULL, hwpoison_unpoison, "%lli\n");

static void pfn_inject_exit(void)
{
	debugfs_remove_recursive(hwpoison_dir);
}

static int pfn_inject_init(void)
{
	struct dentry *dentry;

	hwpoison_dir = debugfs_create_dir("hwpoison", NULL);
	if (hwpoison_dir == NULL)
		return -ENOMEM;

	/*
	 * Note that the below poison/unpoison interfaces do not involve
	 * hardware status change, hence do not require hardware support.
	 * They are mainly for testing hwpoison in software level.
	 */
	dentry = debugfs_create_file("corrupt-pfn", 0200, hwpoison_dir,
					  NULL, &hwpoison_fops);
	if (!dentry)
		goto fail;

	dentry = debugfs_create_file("unpoison-pfn", 0200, hwpoison_dir,
				     NULL, &unpoison_fops);
	if (!dentry)
		goto fail;

	dentry = debugfs_create_u32("corrupt-filter-enable", 0600,
				    hwpoison_dir, &hwpoison_filter_enable);
	if (!dentry)
		goto fail;

	dentry = debugfs_create_u32("corrupt-filter-dev-major", 0600,
				    hwpoison_dir, &hwpoison_filter_dev_major);
	if (!dentry)
		goto fail;

	dentry = debugfs_create_u32("corrupt-filter-dev-minor", 0600,
				    hwpoison_dir, &hwpoison_filter_dev_minor);
	if (!dentry)
		goto fail;

	dentry = debugfs_create_u64("corrupt-filter-flags-mask", 0600,
				    hwpoison_dir, &hwpoison_filter_flags_mask);
	if (!dentry)
		goto fail;

	dentry = debugfs_create_u64("corrupt-filter-flags-value", 0600,
				    hwpoison_dir, &hwpoison_filter_flags_value);
	if (!dentry)
		goto fail;

#ifdef CONFIG_MEMCG
	dentry = debugfs_create_u64("corrupt-filter-memcg", 0600,
				    hwpoison_dir, &hwpoison_filter_memcg);
	if (!dentry)
		goto fail;
#endif

	return 0;
fail:
	pfn_inject_exit();
	return -ENOMEM;
}

module_init(pfn_inject_init);
module_exit(pfn_inject_exit);
MODULE_LICENSE("GPL");
t'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/include/net/inet_frag.h?id=9665b74562ab95bcf1b0684d599bc6779c433fca'>Collapse</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>
/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>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-31 19:03:21 +0100</td></tr>
<tr><th>committer</th><td>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-31 20:22:18 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/ethernet?id=aaaec6fc755447a1d056765b11b24d8ff2b81366'>aaaec6fc755447a1d056765b11b24d8ff2b81366</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/ethernet?id=aaaec6fc755447a1d056765b11b24d8ff2b81366'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=aaaec6fc755447a1d056765b11b24d8ff2b81366'>a7f4167960ee1df86739905b6ccdeb95465bfe5f</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/ethernet?id=aaaec6fc755447a1d056765b11b24d8ff2b81366'>net/ethernet</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/ethernet?id=08d85f3ea99f1eeafc4e8507936190e86a16ee8c'>08d85f3ea99f1eeafc4e8507936190e86a16ee8c</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/ethernet?id=aaaec6fc755447a1d056765b11b24d8ff2b81366&amp;id2=08d85f3ea99f1eeafc4e8507936190e86a16ee8c'>diff</a>)</td></tr></table>
<div class='commit-subject'>x86/irq: Make irq activate operations symmetric</div><div class='commit-msg'>The recent commit which prevents double activation of interrupts unearthed
interesting code in x86. The code (ab)uses irq_domain_activate_irq() to
reconfigure an already activated interrupt. That trips over the prevention
code now.

Fix it by deactivating the interrupt before activating the new configuration.

Fixes: 08d85f3ea99f1 "irqdomain: Avoid activating interrupts more than once"
Reported-and-tested-by: Mike Galbraith &lt;efault@gmx.de&gt;
Reported-and-tested-by: Borislav Petkov &lt;bp@alien8.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Andrey Ryabinin &lt;aryabinin@virtuozzo.com&gt;
Cc: Marc Zyngier &lt;marc.zyngier@arm.com&gt;
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701311901580.3457@nanos

</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=aaaec6fc755447a1d056765b11b24d8ff2b81366'>Diffstat</a> (limited to 'net/ethernet')</div><table summary='diffstat' class='diffstat'>