On Wed, Sep 12, 2012 at 05:00:48PM +0900, OGAWA Hirofumi wrote: > Fengguang Wu <fengguang...@intel.com> writes: > > > On Wed, Sep 12, 2012 at 03:28:42AM +0900, OGAWA Hirofumi wrote: > >> > >> If bdi has BDI_CAP_NO_WRITEBACK, bdi_forker_thread() doesn't start > >> writeback thread. This means there is no consumer of work item made > >> by bdi_queue_work(). > >> > >> This adds to checking of !bdi_cap_writeback_dirty(sb->s_bdi) before > >> calling bdi_queue_work(), otherwise queued work never be consumed. > > > > Thanks for catching this! Does this bug have any side effects other > > than memory leaking? > > > > It may be possible for some caller that actually expect it to do some > > work to make progress, otherwise will eventually block. If so, we'll > > need to fix the caller. > > If used custom bdi with BDI_CAP_NO_WRITEBACK, wait_for_completion() > (e.g. sync_inodes_sb()) will be blocked forever.
The sync(2) block cannot be fixed by this patch? > I tested by custom bdi with BDI_CAP_NO_WRITEBACK - sync(2) blocked > forever by this reason. What's your test script? How do you create/use that custom bdi? Thanks, Fengguang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/