Revision df9576def004d2cd5beedc00cb6e8901427634b9 authored by Yang Shi on 03 August 2019, 04:48:37 UTC, committed by Linus Torvalds on 03 August 2019, 14:02:00 UTC
When running ltp's oom test with kmemleak enabled, the below warning was
triggerred since kernel detects __GFP_NOFAIL & ~__GFP_DIRECT_RECLAIM is
passed in:

  WARNING: CPU: 105 PID: 2138 at mm/page_alloc.c:4608 __alloc_pages_nodemask+0x1c31/0x1d50
  Modules linked in: loop dax_pmem dax_pmem_core ip_tables x_tables xfs virtio_net net_failover virtio_blk failover ata_generic virtio_pci virtio_ring virtio libata
  CPU: 105 PID: 2138 Comm: oom01 Not tainted 5.2.0-next-20190710+ #7
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014
  RIP: 0010:__alloc_pages_nodemask+0x1c31/0x1d50
  ...
   kmemleak_alloc+0x4e/0xb0
   kmem_cache_alloc+0x2a7/0x3e0
   mempool_alloc_slab+0x2d/0x40
   mempool_alloc+0x118/0x2b0
   bio_alloc_bioset+0x19d/0x350
   get_swap_bio+0x80/0x230
   __swap_writepage+0x5ff/0xb20

The mempool_alloc_slab() clears __GFP_DIRECT_RECLAIM, however kmemleak
has __GFP_NOFAIL set all the time due to d9570ee3bd1d4f2 ("kmemleak:
allow to coexist with fault injection").  But, it doesn't make any sense
to have __GFP_NOFAIL and ~__GFP_DIRECT_RECLAIM specified at the same
time.

According to the discussion on the mailing list, the commit should be
reverted for short term solution.  Catalin Marinas would follow up with
a better solution for longer term.

The failure rate of kmemleak metadata allocation may increase in some
circumstances, but this should be expected side effect.

Link: http://lkml.kernel.org/r/1563299431-111710-1-git-send-email-yang.shi@linux.alibaba.com
Fixes: d9570ee3bd1d4f2 ("kmemleak: allow to coexist with fault injection")
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent 68d8681
Raw File
quota.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * quota.c - NTFS kernel quota ($Quota) handling.  Part of the Linux-NTFS
 *	     project.
 *
 * Copyright (c) 2004 Anton Altaparmakov
 */

#ifdef NTFS_RW

#include "index.h"
#include "quota.h"
#include "debug.h"
#include "ntfs.h"

/**
 * ntfs_mark_quotas_out_of_date - mark the quotas out of date on an ntfs volume
 * @vol:	ntfs volume on which to mark the quotas out of date
 *
 * Mark the quotas out of date on the ntfs volume @vol and return 'true' on
 * success and 'false' on error.
 */
bool ntfs_mark_quotas_out_of_date(ntfs_volume *vol)
{
	ntfs_index_context *ictx;
	QUOTA_CONTROL_ENTRY *qce;
	const le32 qid = QUOTA_DEFAULTS_ID;
	int err;

	ntfs_debug("Entering.");
	if (NVolQuotaOutOfDate(vol))
		goto done;
	if (!vol->quota_ino || !vol->quota_q_ino) {
		ntfs_error(vol->sb, "Quota inodes are not open.");
		return false;
	}
	inode_lock(vol->quota_q_ino);
	ictx = ntfs_index_ctx_get(NTFS_I(vol->quota_q_ino));
	if (!ictx) {
		ntfs_error(vol->sb, "Failed to get index context.");
		goto err_out;
	}
	err = ntfs_index_lookup(&qid, sizeof(qid), ictx);
	if (err) {
		if (err == -ENOENT)
			ntfs_error(vol->sb, "Quota defaults entry is not "
					"present.");
		else
			ntfs_error(vol->sb, "Lookup of quota defaults entry "
					"failed.");
		goto err_out;
	}
	if (ictx->data_len < offsetof(QUOTA_CONTROL_ENTRY, sid)) {
		ntfs_error(vol->sb, "Quota defaults entry size is invalid.  "
				"Run chkdsk.");
		goto err_out;
	}
	qce = (QUOTA_CONTROL_ENTRY*)ictx->data;
	if (le32_to_cpu(qce->version) != QUOTA_VERSION) {
		ntfs_error(vol->sb, "Quota defaults entry version 0x%x is not "
				"supported.", le32_to_cpu(qce->version));
		goto err_out;
	}
	ntfs_debug("Quota defaults flags = 0x%x.", le32_to_cpu(qce->flags));
	/* If quotas are already marked out of date, no need to do anything. */
	if (qce->flags & QUOTA_FLAG_OUT_OF_DATE)
		goto set_done;
	/*
	 * If quota tracking is neither requested, nor enabled and there are no
	 * pending deletes, no need to mark the quotas out of date.
	 */
	if (!(qce->flags & (QUOTA_FLAG_TRACKING_ENABLED |
			QUOTA_FLAG_TRACKING_REQUESTED |
			QUOTA_FLAG_PENDING_DELETES)))
		goto set_done;
	/*
	 * Set the QUOTA_FLAG_OUT_OF_DATE bit thus marking quotas out of date.
	 * This is verified on WinXP to be sufficient to cause windows to
	 * rescan the volume on boot and update all quota entries.
	 */
	qce->flags |= QUOTA_FLAG_OUT_OF_DATE;
	/* Ensure the modified flags are written to disk. */
	ntfs_index_entry_flush_dcache_page(ictx);
	ntfs_index_entry_mark_dirty(ictx);
set_done:
	ntfs_index_ctx_put(ictx);
	inode_unlock(vol->quota_q_ino);
	/*
	 * We set the flag so we do not try to mark the quotas out of date
	 * again on remount.
	 */
	NVolSetQuotaOutOfDate(vol);
done:
	ntfs_debug("Done.");
	return true;
err_out:
	if (ictx)
		ntfs_index_ctx_put(ictx);
	inode_unlock(vol->quota_q_ino);
	return false;
}

#endif /* NTFS_RW */
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