Messages in this thread | | | Date | Wed, 29 Apr 2015 16:23:28 +0900 | From | Sergey Senozhatsky <> | Subject | Re: [PATCHv3 9/9] zram: add dynamic device add/remove functionality |
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On (04/29/15 16:02), Sergey Senozhatsky wrote: > sure. I was talking about this one: > > CPU0 CPU1 > umount > zram_remove() > lock ->bd_mutex > zram_reset_device() > unlock ->bd_mutex > disksize_store > mount > echo 'test' > /mnt/test > kfree zram > zram write >
I'll take a look later today. currently I think of something like:
sysfs_remove_group() lock ->bd_mutex ... check ->bd_openers
zram_reset_device() blk_cleanup_queue() del_gendisk() put_disk()
unlock ->bd_mutex bdput bdev
idr_remove() kfree(zram)
iow, idr_remove() and kfree() are done outside of ->bd_mutex lock. but I may be wrong. haven't tested yet. but seems reasonable: we invalidate ->bdev, delete partitions, etc., holding ->bd_mutex and then release ->bdev, which does final put. need to check that in detail.
-ss
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