linux-kernel - Re: [PATCH] iommu/arm-smmu: Demote error messages to debug in shutdown callback

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 for Android: free password hash cracker in your pocket

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

Message-ID: <006edb3b-8834-41fe-d9d1-fe873edfca99@arm.com>
Date:   Thu, 23 Apr 2020 10:28:58 +0100
From:   Robin Murphy <robin.murphy@....com>
To:     Sai Prakash Ranjan <saiprakash.ranjan@...eaurora.org>,
        Doug Anderson <dianders@...omium.org>,
        Will Deacon <will@...nel.org>
Cc:     linux-arm-msm <linux-arm-msm@...r.kernel.org>,
        linux-arm-msm-owner@...r.kernel.org,
        Joerg Roedel <joro@...tes.org>,
        LKML <linux-kernel@...r.kernel.org>,
        iommu@...ts.linux-foundation.org
Subject: Re: [PATCH] iommu/arm-smmu: Demote error messages to debug in
 shutdown callback

On 2020-04-23 9:17 am, Sai Prakash Ranjan wrote:
[...]
>> Any update on the status here?  If I'm reading the conversation above,
>> Robin said: "we'll *always* see the warning because there's no way to
>> tear down the default DMA domains, and even if all devices *have* been
>> nicely quiesced there's no way to tell".  Did I understand that
>> properly?  If so, it seems like it's fully expected to see this
>> message on every reboot and it doesn't necessarily signify anything
>> bad.
>>
> 
> Understanding is the same, waiting for Will and Robin to check if its OK
> to make the message more friendly.

The way I see it, we essentially just want *something* visible that will 
correlate with any misbehaviour that *might* result from turning off a 
possibly-live context. How about simply "disabling translation", at 
dev_warn or dev_info level?

Robin.