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

From: Dmitry Osipenko
Date: Fri Sep 04 2020 - 05:20:07 EST


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.