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| author | Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> | 2023-02-08 18:36:49 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-03-10 11:28:18 +0300 |
| commit | 8f0d9e6c53c997107d928bed811876f71dd13866 (patch) | |
| tree | 74cfca66720cef6a8827150351031dc07691a540 | |
| parent | 9903313fb8b43372c4338693b5da4f72590b1b1f (diff) | |
| download | linux-8f0d9e6c53c997107d928bed811876f71dd13866.tar.xz | |
xen/grant-dma-iommu: Implement a dummy probe_device() callback
[ Upstream commit 2062f9fb6445451b189595e295765c69f43bc12e ]
Update stub IOMMU driver (which main purpose is to reuse generic
IOMMU device-tree bindings by Xen grant DMA-mapping layer on Arm)
according to the recent changes done in the following
commit 57365a04c921 ("iommu: Move bus setup to IOMMU device registration").
With probe_device() callback being called during IOMMU device registration,
the uninitialized callback just leads to the "kernel NULL pointer
dereference" issue during boot. Fix that by adding a dummy callback.
Looks like the release_device() callback is not mandatory to be
implemented as IOMMU framework makes sure that callback is initialized
before dereferencing.
Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Fixes: 57365a04c921 ("iommu: Move bus setup to IOMMU device registration")
Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Tested-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Link: https://lore.kernel.org/r/20230208153649.3604857-1-olekstysh@gmail.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | drivers/xen/grant-dma-iommu.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/xen/grant-dma-iommu.c b/drivers/xen/grant-dma-iommu.c index 16b8bc0c0b33..6a9fe02c6bfc 100644 --- a/drivers/xen/grant-dma-iommu.c +++ b/drivers/xen/grant-dma-iommu.c @@ -16,8 +16,15 @@ struct grant_dma_iommu_device { struct iommu_device iommu; }; -/* Nothing is really needed here */ -static const struct iommu_ops grant_dma_iommu_ops; +static struct iommu_device *grant_dma_iommu_probe_device(struct device *dev) +{ + return ERR_PTR(-ENODEV); +} + +/* Nothing is really needed here except a dummy probe_device callback */ +static const struct iommu_ops grant_dma_iommu_ops = { + .probe_device = grant_dma_iommu_probe_device, +}; static const struct of_device_id grant_dma_iommu_of_match[] = { { .compatible = "xen,grant-dma" }, |