linux-kernel - RE: [PATCH v5 05/10] scsi: ufshpb: Region inactivation in host mode

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <DM6PR04MB65751EE32D25C7E57A6BABE8FC6B9@DM6PR04MB6575.namprd04.prod.outlook.com>
Date:   Tue, 16 Mar 2021 08:30:06 +0000
From:   Avri Altman <Avri.Altman@....com>
To:     Can Guo <cang@...eaurora.org>
CC:     "James E . J . Bottomley" <jejb@...ux.vnet.ibm.com>,
        "Martin K . Petersen" <martin.petersen@...cle.com>,
        "linux-scsi@...r.kernel.org" <linux-scsi@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>,
        Bart Van Assche <bvanassche@....org>,
        yongmyung lee <ymhungry.lee@...sung.com>,
        Daejun Park <daejun7.park@...sung.com>,
        "alim.akhtar@...sung.com" <alim.akhtar@...sung.com>,
        "asutoshd@...eaurora.org" <asutoshd@...eaurora.org>,
        Zang Leigang <zangleigang@...ilicon.com>,
        Avi Shchislowski <Avi.Shchislowski@....com>,
        Bean Huo <beanhuo@...ron.com>,
        "stanley.chu@...iatek.com" <stanley.chu@...iatek.com>
Subject: RE: [PATCH v5 05/10] scsi: ufshpb: Region inactivation in host mode

> >> ---
> >>  drivers/scsi/ufs/ufshpb.c | 14 ++++++++++++++
> >>  drivers/scsi/ufs/ufshpb.h |  1 +
> >>  2 files changed, 15 insertions(+)
> >>
> >> diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
> >> index 6f4fd22eaf2f..0744feb4d484 100644
> >> --- a/drivers/scsi/ufs/ufshpb.c
> >> +++ b/drivers/scsi/ufs/ufshpb.c
> >> @@ -907,6 +907,7 @@ static int ufshpb_execute_umap_req(struct
> >> ufshpb_lu *hpb,
> >>
> >>      blk_execute_rq_nowait(q, NULL, req, 1, ufshpb_umap_req_compl_fn);
> >>
> >> +    hpb->stats.umap_req_cnt++;
> >>      return 0;
> >>  }
> >>
> >> @@ -1103,6 +1104,12 @@ static int ufshpb_issue_umap_req(struct
> >> ufshpb_lu *hpb,
> >>      return -EAGAIN;
> >>  }
> >>
> >> +static int ufshpb_issue_umap_single_req(struct ufshpb_lu *hpb,
> >> +                                    struct ufshpb_region *rgn)
> >> +{
> >> +    return ufshpb_issue_umap_req(hpb, rgn);
> >> +}
> >> +
> >>  static int ufshpb_issue_umap_all_req(struct ufshpb_lu *hpb)
> >>  {
> >>      return ufshpb_issue_umap_req(hpb, NULL);
> >> @@ -1115,6 +1122,10 @@ static void __ufshpb_evict_region(struct
> >> ufshpb_lu *hpb,
> >>      struct ufshpb_subregion *srgn;
> >>      int srgn_idx;
> >>
> >> +
> >> +    if (hpb->is_hcm && ufshpb_issue_umap_single_req(hpb, rgn))
> >
> > __ufshpb_evict_region() is called with rgn_state_lock held and IRQ
> > disabled,
> > when ufshpb_issue_umap_single_req() invokes blk_execute_rq_nowait(),
> > below
> > warning shall pop up every time, fix it?
> >
> > void blk_execute_rq_nowait(struct request_queue *q, struct gendisk
> > *bd_disk,
> >                  struct request *rq, int at_head,
> >                          rq_end_io_fn *done)
> > {
> >       WARN_ON(irqs_disabled());
> > ...
> >
> 
> Moreover, since we are here with rgn_state_lock held and IRQ disabled,
> in ufshpb_get_req(), rq = kmem_cache_alloc(hpb->map_req_cache,
> GFP_KERNEL)
> has the GFP_KERNEL flag, scheduling while atomic???
I think your comment applies to  ufshpb_issue_umap_all_req as well,
Which is called from slave_configure/scsi_add_lun.

Since the host-mode series is utilizing the framework laid by the device-mode,
Maybe you can add this comment to  Daejun's last version?

Thanks,
Avri

> 
> Can Guo.
> 
> > Thanks.
> > Can Guo.
> >
> >> +            return;
> >> +
> >>      lru_info = &hpb->lru_info;
> >>
> >>      dev_dbg(&hpb->sdev_ufs_lu->sdev_dev, "evict region %d\n",
> >> rgn->rgn_idx);
> >> @@ -1855,6 +1866,7 @@ ufshpb_sysfs_attr_show_func(rb_noti_cnt);
> >>  ufshpb_sysfs_attr_show_func(rb_active_cnt);
> >>  ufshpb_sysfs_attr_show_func(rb_inactive_cnt);
> >>  ufshpb_sysfs_attr_show_func(map_req_cnt);
> >> +ufshpb_sysfs_attr_show_func(umap_req_cnt);
> >>
> >>  static struct attribute *hpb_dev_stat_attrs[] = {
> >>      &dev_attr_hit_cnt.attr,
> >> @@ -1863,6 +1875,7 @@ static struct attribute *hpb_dev_stat_attrs[] =
> >> {
> >>      &dev_attr_rb_active_cnt.attr,
> >>      &dev_attr_rb_inactive_cnt.attr,
> >>      &dev_attr_map_req_cnt.attr,
> >> +    &dev_attr_umap_req_cnt.attr,
> >>      NULL,
> >>  };
> >>
> >> @@ -1978,6 +1991,7 @@ static void ufshpb_stat_init(struct ufshpb_lu
> >> *hpb)
> >>      hpb->stats.rb_active_cnt = 0;
> >>      hpb->stats.rb_inactive_cnt = 0;
> >>      hpb->stats.map_req_cnt = 0;
> >> +    hpb->stats.umap_req_cnt = 0;
> >>  }
> >>
> >>  static void ufshpb_param_init(struct ufshpb_lu *hpb)
> >> diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
> >> index bd4308010466..84598a317897 100644
> >> --- a/drivers/scsi/ufs/ufshpb.h
> >> +++ b/drivers/scsi/ufs/ufshpb.h
> >> @@ -186,6 +186,7 @@ struct ufshpb_stats {
> >>      u64 rb_inactive_cnt;
> >>      u64 map_req_cnt;
> >>      u64 pre_req_cnt;
> >> +    u64 umap_req_cnt;
> >>  };
> >>
> >>  struct ufshpb_lu {