Messages in this thread | | | Date | Tue, 22 Jun 2021 08:12:10 -0700 | From | Luis Chamberlain <> | Subject | Re: [PATCH v3 1/3] zram: fix crashes due to use of cpu hotplug multistate |
| |
On Tue, Jun 22, 2021 at 09:39:40AM +0200, Greg KH wrote: > On Mon, Jun 21, 2021 at 04:30:11PM -0700, Luis Chamberlain wrote: > > CPU 1 CPU 2 > > > > class_unregister(...); > > Now the sysfs files are removed and invalidated for all devices > associated with that class.
You're right the disksize_store() would have to happen before.
> > idr_for_each(...); > > zram_debugfs_destroy(); > > disksize_store(...); > > How will this call into the kobject's store function if > class_unregister() has already happened?
The disksize_store() would indeed have to happen before.
> > idr_destroy(...); > > unregister_blkdev(...); > > Ah, it's a block device's store function you are worried about, not the > class one?
In this case its about any files which can change the cpu compression streams.
> > diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c > > index cf8deecc39ef..431b60cd85c1 100644 > > --- a/drivers/block/zram/zram_drv.c > > +++ b/drivers/block/zram/zram_drv.c > > @@ -44,6 +44,8 @@ static DEFINE_MUTEX(zram_index_mutex); > > static int zram_major; > > static const char *default_compressor = CONFIG_ZRAM_DEF_COMP; > > > > +bool zram_up; > > static?
Will fix.
> > + > > /* Module params (documentation at end) */ > > static unsigned int num_devices = 1; > > /* > > @@ -1704,6 +1706,7 @@ static void zram_reset_device(struct zram *zram) > > comp = zram->comp; > > disksize = zram->disksize; > > zram->disksize = 0; > > + zram->comp = NULL; > > Is this a new change?
It is a sanity change, but indeed, it is separate. I'll let Minchan decide if he would prefer this to go out as a separate change.
Luis
| |