linux-kernel - Re: [PATCH v2 2/3] iommu/tegra-smmu: Rework .probe_device and .attach

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: <e5b9f269-3ddd-d4e5-de26-413414c3ccf2@gmail.com>
Date:   Wed, 30 Sep 2020 08:48:49 +0300
From:   Dmitry Osipenko <digetx@...il.com>
To:     Nicolin Chen <nicoleotsuka@...il.com>
Cc:     thierry.reding@...il.com, joro@...tes.org, krzk@...nel.org,
        vdumpa@...dia.com, jonathanh@...dia.com,
        linux-tegra@...r.kernel.org, iommu@...ts.linux-foundation.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 2/3] iommu/tegra-smmu: Rework .probe_device and
 .attach_dev

30.09.2020 08:39, Nicolin Chen пишет:
> On Wed, Sep 30, 2020 at 08:24:02AM +0300, Dmitry Osipenko wrote:
>> 30.09.2020 03:30, Nicolin Chen пишет:
>>> +	/*
>>> +	 * IOMMU core allows -ENODEV return to carry on. So bypass any call
>>> +	 * from bus_set_iommu() during tegra_smmu_probe(), as a device will
>>> +	 * call in again via of_iommu_configure when fwspec is prepared.
>>> +	 */
>>> +	if (!mc->smmu || !fwspec || fwspec->ops != &tegra_smmu_ops)
>>>  		return ERR_PTR(-ENODEV);
>>
>> The !mc->smmu can't be true.
> 
> Are you sure? I have removed the "mc->smmu = smmu" in probe() with
> this change. So the only time "mc->smmu == !NULL" is after probe()
> of SMMU driver is returned. As my comments says, tegra_smmu_probe()
> calls in this function via bus_set_iommu(), so mc->smmu can be NULL
> in this case.
> 

I missed that.