| 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
| ||
|
Date: Wed, 17 Mar 2021 14:19:30 +0900
From: Daejun Park <daejun7.park@...sung.com>
To: Can Guo <cang@...eaurora.org>,
Daejun Park <daejun7.park@...sung.com>
CC: Avri Altman <Avri.Altman@....com>,
"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>,
ALIM AKHTAR <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: 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?
>>
>> Hi Avri, Can Guo
>>
>> I think ufshpb_issue_umap_single_req() can be moved to end of
>> ufshpb_evict_region().
>> Then we can avoid rgn_state_lock when it sends unmap command.
>
>I am not the expert here, please you two fix it. I am just reporting
>what can be wrong. Anyways, ufshpb_issue_umap_single_req() should not
>be called with rgn_state_lock held - think about below (another deadly)
>scenario.
>
>lock(rgn_state_lock)
> ufshpb_issue_umap_single_req()
> ufshpb_prep()
> lock(rgn_state_lock) <---------- recursive spin_lock
>
>BTW, @Daejun shouldn't we stop passthrough cmds from stepping
>into ufshpb_prep()? In current code, you are trying to use below
>check to block cmds other than write/discard/read, but a passthrough
>cmd can not be blocked by the check.
>
> if (!ufshpb_is_write_or_discard_cmd(cmd) &&
> !ufshpb_is_read_cmd(cmd) )
> return 0;
I found this problem too. I fixed it and submit next patch.
if (blk_rq_is_scsi(cmd->request) ||
(!ufshpb_is_write_or_discard_cmd(cmd) &&
!ufshpb_is_read_cmd(cmd)))
return 0;
Thanks,
Daejun
>Thanks,
>Can Guo.
>
>>
>> Thanks,
>> Daejun
>>
>>
>>> 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 {
>>>
>>>
>>>
>
>
>
Powered by blists - more mailing lists