Re: [PATCH RESEND v3] iommu/tegra-smmu: Add missing locks around mapping operations

From: Dmitry Osipenko
Date: Fri Sep 04 2020 - 05:25:35 EST


04.09.2020 12:19, Dmitry Osipenko пишет:
> 04.09.2020 12:05, Joerg Roedel пишет:
>> On Fri, Aug 14, 2020 at 07:22:52PM +0300, Dmitry Osipenko wrote:
>>> The mapping operations of the Tegra SMMU driver are subjected to a race
>>> condition issues because SMMU Address Space isn't allocated and freed
>>> atomically, while it should be. This patch makes the mapping operations
>>> atomic, it fixes an accidentally released Host1x Address Space problem
>>> which happens while running multiple graphics tests in parallel on
>>> Tegra30, i.e. by having multiple threads racing with each other in the
>>> Host1x's submission and completion code paths, performing IOVA mappings
>>> and unmappings in parallel.
>>>
>>> Cc: <stable@xxxxxxxxxxxxxxx>
>>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>>
>> Thierry, does this change look good to you?
>>
>
> Hello Joerg and Thierry,
>
> Please take into account that there is a v5 now that I sent out a day
> ago, it's more optimized version and supports both atomic and non-atomic
> GFP flags for the mapping operation.
>

https://patchwork.ozlabs.org/project/linux-tegra/patch/20200901203730.27865-1-digetx@xxxxxxxxx/