On 31/05/2021 06:07, Ming Lei wrote:

Hello Martin,


Fix two memory leaks and one double free issue in alloc/add host
code path.


V3:
	- fix memory leak caused in scsi_host_alloc
	- comment typo suggested by John

V2:
	- add patch 2 for addressing shost leak in case of adding host
	  failure, reported by John Garry.

Ming Lei (3):
   scsi: core: use put_device() to release host
   scsi: core: fix failure handling of scsi_add_host_with_dma
   scsi: core: put ->shost_gendev.parent in failure handling path

  drivers/scsi/hosts.c | 25 ++++++++++++-------------
  1 file changed, 12 insertions(+), 13 deletions(-)

Cc: Bart Van Assche <bvanassche@acm.org>
Cc: John Garry <redacted>
Cc: Hannes Reinecke <hare@suse.de>

I tested this again with the same experiment as before to error in
scsi_add_host_with_dma(), and we don't call scsi_host_dev_release() now. 
The shost_gendev dev refcount is 2 upon exit in scsi_add_host_with_dma().

We don't call scsi_host_cls_release() either, so I guess a ref count is 
leaked for shost_dev - I see its refcount is 1 at exit in 
scsi_add_host_with_dma(). We have the device_initialize(), device_add(), 
device_del() in the alloc and add host functions, but I don't know who 
is responsible for the final "device put".

Thanks,
John