Re: [PATCH v2 1/3] scsi: ufs: Put SCSI host after remove it

[cang]

On 2019-12-11 18:37, Avri Altman wrote:
> > In ufshcd_remove(), after SCSI host is removed, put it once so that 
> > its resources
> > can be released.
> >
> > Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
>
> This is not really part of this patchset, is it?

Hi Avri,

I put this change in the same patchset due to
#1. The main patch has dependency on it
#2. Consider a scenario where platform driver is also compiled as a 
module, say ufs_qcom.ko.
    In this case, we have two modules, ufs-qcom.ko and ufs-bsg.ko. If do 
insmod ufs-qcom.ko
    then rmmod ufs-qcom.ko and do insmod ufs-qcom.ko again, without this 
change, because scsi
    host was not release, the new scsi host will have a different host 
number, meaning
    hba->host->host_no will be 1, but not 0. Now if do insmod ufs-bsg.ko 
now, the ufs-bsg dev
    created in /dev/bsg/ will be ufs-bsg1, but not ufs-bsg0. If keep 
trying these operations,
    the ufs-bsg device's name will be messed up. This change make sure 
after ufs-qcom.ko is removed
    and installed back, its hba->host->host_no stays 0, so that ufs-bsg 
device name stays same.

Thanks,

Can Guo.

> > ---
> >  drivers/scsi/ufs/ufshcd.c | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c 
> > index
> > b5966fa..a86b0fd 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -8251,6 +8251,7 @@ void ufshcd_remove(struct ufs_hba *hba)
> >         ufs_bsg_remove(hba);
> >         ufs_sysfs_remove_nodes(hba->dev);
> >         scsi_remove_host(hba->host);
> > +       scsi_host_put(hba->host);
> >         /* disable interrupts */
> >         ufshcd_disable_intr(hba, hba->intr_mask);
> >         ufshcd_hba_stop(hba, true);
> > --
> > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora 
> > Forum,
> > a Linux Foundation Collaborative Project