David Chinner wrote:
On Tue, Oct 16, 2007 at 03:18:02PM +1000, Lachlan McIlroy wrote:
Could mp->m_quotainfo become NULL after this check but before we
lock the list with xfs_qm_mplist_lock()? There doesn't seem to
be any locking to protect changes to this field?
Possible - in theory. Likely - no. We do the same unlocked check in a
few places...
The mplist lock doesnt prevent the quotainfo going away while its held.
It's just guarding a hashlist that lives in quotainfo structure.
So none of this code prevents a quotaoff race.
In the short term this change restores the original checks. But in the
longer term we should review the locking in the quota system, possibly
adding a quotaoff lock to xfs_mount_t.
Don
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