linux-kernel - Re: [PATCH v1] scsi: ufs: core: print trs for pending requests in MCQ 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] [day] [month] [year] [list]

Message-ID: <aed019c6-9729-1892-2c8f-c97bcc7efd35@quicinc.com>
Date:   Mon, 13 Mar 2023 19:29:52 +0800
From:   Ziqi Chen <quic_ziqichen@...cinc.com>
To:     Bart Van Assche <bvanassche@....org>, <quic_asutoshd@...cinc.com>,
        <quic_cang@...cinc.com>, <quic_nguyenb@...cinc.com>,
        <mani@...nel.org>, <stanley.chu@...iatek.com>,
        <adrian.hunter@...el.com>, <beanhuo@...ron.com>,
        <avri.altman@....com>, <junwoo80.lee@...sung.com>,
        <martin.petersen@...cle.com>
CC:     <linux-scsi@...r.kernel.org>,
        Alim Akhtar <alim.akhtar@...sung.com>,
        "James E.J. Bottomley" <jejb@...ux.ibm.com>,
        open list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v1] scsi: ufs: core: print trs for pending requests in MCQ
 mode

Hi Bart,

Good idea, let met re-design it.

Thanks,
Ziqi

On 3/10/2023 1:28 AM, Bart Van Assche wrote:
> On 3/8/23 21:01, Ziqi Chen wrote:
>> +static void ufshcd_print_trs_all(struct ufs_hba *hba, bool pr_prdt)
>> +{
>> +    const struct ufshcd_lrb *lrbp;
>> +    int tag;
>> +
>> +    for (tag = 0; tag < hba->nutrs; tag++) {
>> +        lrbp = &hba->lrb[tag];
>> +
>> +        if (lrbp->cmd)
>> +            ufshcd_print_tr(hba, tag, pr_prdt);
>>       }
>>   }
> 
> There is a race in this code: lrbp->cmd may be cleared after it has been 
> read and before or while ufshcd_print_tr() is in progress. How about 
> preventing that race by blk_mq_tagset_busy_iter() to iterate over 
> pending SCSI commands?
> 
> Thanks,
> 
> Bart.