> -----Original Message----- > From: NeilBrown [mailto:neilb@xxxxxxx] > Sent: Tuesday, February 22, 2011 1:50 AM > To: Wojcik, Krzysztof > Cc: linux-raid@xxxxxxxxxxxxxxx > Subject: Re: Single-drive RAID0 > > On Mon, 21 Feb 2011 14:11:51 +0000 "Wojcik, Krzysztof" > <krzysztof.wojcik@xxxxxxxxx> wrote: > > > Hi, > > > > I tested your proposal. > > It resolve the problem. > > Thanks! > > > What are your future plans? > > Do you need to consult the patch with someone involved in the block > devices code? > > When can I expect final patch? > > Here it is. As you can see it is quite different - I figured out what > is > really going on.. > > > > > > > > > > If it does, then we can explore more... > > > Did you say that this works better on earlier kernels? If so, what > is > > > the > > > latest kernel that you have tried that you don't have this problem > on? > > > > I've tested on kernel 2.6.32 from RHEL6.0 and, if I remember > correctly, 2.6.34- they work properly. > > That fits - I discovered that I broke it in 2.6.35. > > Thanks, > NeilBrown Hi, I confirm. This patch resolve the problem. I did tests on your current top of for-next branch and issue is not reproducible. Thank for your cooperation! :-) Regards Krzysztof > > From b7fea734c7780ca80f58fb87a6c9f55aa83314d7 Mon Sep 17 00:00:00 2001 > From: NeilBrown <neilb@xxxxxxx> > Date: Tue, 22 Feb 2011 11:48:03 +1100 > Subject: [PATCH] md: Fix - again - partition detection when array > becomes active > > Revert > b821eaa572fd737faaf6928ba046e571526c36c6 > and > f3b99be19ded511a1bf05a148276239d9f13eefa > > When I wrote the first of these I had a wrong idea about the > lifetime of 'struct block_device'. It can disappear at any time that > the block device is not open if it falls out of the inode cache. > > So relying on the 'size' recorded with it to detect when the > device size has changed and so we need to revalidate, is wrong. > > Rather, we really do need the 'changed' attribute stored directly in > the mddev and set/tested as appropriate. > > Without this patch, a sequence of: > mknod / open / close / unlink > > (which can cause a block_device to be created and then destroyed) > will result in a rescan of the partition table and consequence removal > and addition of partitions. > Several of these in a row can get udev racing to create and unlink and > other code can get confused. > > With the patch, the rescan is only performed when needed and so there > are no races. > > This is suitable for any stable kernel from 2.6.35. > > Reported-by: "Wojcik, Krzysztof" <krzysztof.wojcik@xxxxxxxxx> > Signed-off-by: NeilBrown <neilb@xxxxxxx> > Cc: stable@xxxxxxxxxx > --- > drivers/md/md.c | 22 +++++++++++++++++++++- > drivers/md/md.h | 2 ++ > 2 files changed, 23 insertions(+), 1 deletions(-) > > diff --git a/drivers/md/md.c b/drivers/md/md.c > index 330addf..818313e 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -4627,6 +4627,7 @@ static int do_md_run(mddev_t *mddev) > } > set_capacity(mddev->gendisk, mddev->array_sectors); > revalidate_disk(mddev->gendisk); > + mddev->changed = 1; > kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE); > out: > return err; > @@ -4715,6 +4716,7 @@ static void md_clean(mddev_t *mddev) > mddev->sync_speed_min = mddev->sync_speed_max = 0; > mddev->recovery = 0; > mddev->in_sync = 0; > + mddev->changed = 0; > mddev->degraded = 0; > mddev->safemode = 0; > mddev->bitmap_info.offset = 0; > @@ -4830,6 +4832,7 @@ static int do_md_stop(mddev_t * mddev, int mode, > int is_open) > > set_capacity(disk, 0); > mutex_unlock(&mddev->open_mutex); > + mddev->changed = 1; > revalidate_disk(disk); > > if (mddev->ro) > @@ -6014,7 +6017,7 @@ static int md_open(struct block_device *bdev, > fmode_t mode) > atomic_inc(&mddev->openers); > mutex_unlock(&mddev->open_mutex); > > - check_disk_size_change(mddev->gendisk, bdev); > + check_disk_change(bdev); > out: > return err; > } > @@ -6029,6 +6032,21 @@ static int md_release(struct gendisk *disk, > fmode_t mode) > > return 0; > } > + > +static int md_media_changed(struct gendisk *disk) > +{ > + mddev_t *mddev = disk->private_data; > + > + return mddev->changed; > +} > + > +static int md_revalidate(struct gendisk *disk) > +{ > + mddev_t *mddev = disk->private_data; > + > + mddev->changed = 0; > + return 0; > +} > static const struct block_device_operations md_fops = > { > .owner = THIS_MODULE, > @@ -6039,6 +6057,8 @@ static const struct block_device_operations > md_fops = > .compat_ioctl = md_compat_ioctl, > #endif > .getgeo = md_getgeo, > + .media_changed = md_media_changed, > + .revalidate_disk= md_revalidate, > }; > > static int md_thread(void * arg) > diff --git a/drivers/md/md.h b/drivers/md/md.h > index 7e90b85..12215d4 100644 > --- a/drivers/md/md.h > +++ b/drivers/md/md.h > @@ -274,6 +274,8 @@ struct mddev_s > atomic_t active; /* general refcount */ > atomic_t openers; /* number of active opens */ > > + int changed; /* True if we might need to > + * reread partition info */ > int degraded; /* whether md should consider > * adding a spare > */ > -- > 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
