[ Upstream commit bc17ac285fb708f22a8fa2c0ed32eceb1d37e6d6 ]

host1x_debug_output() and host1x_debug_cont() used vsnprintf(), which
returns the length the formatted string would have reached with an
unbounded buffer. That return value was passed straight to o->fn as
the number of bytes to emit.

This could cause a read past end of the output buffer if a call to
host1x_debug_* produced a string longer than 256 bytes. This only
affected the debugfs files as the printk debug sink ignores the
number of bytes. In practice, this is very unlikely to occur.

Fix by switching to vscnprintf(), which returns the number of bytes
actually written.

Fixes: 6236451d83a7 ("gpu: host1x: Add debug support")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260609-b4-host1x-small-fixes-a-v1-4-7c1131c0b3ad@nvidia.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit eb896850964d3dfce291b4fdff9c2d42d85e564b ]

When a gather longer than 2*TRACE_MAX_LENGTH (256) words is traced
through host1x_cdma_push_gather, the reported BO offset drifts from
the third iteration onward.

Fix the calculation by properly calculating the value on each loop
rather than accumulating.

In reality, gathers tend to be pretty short so this is unlikely to
ever have been observed.

Fixes: b40d02bf96e0 ("gpu: host1x: Use struct host1x_bo pointers in traces")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260609-b4-host1x-small-fixes-a-v1-3-7c1131c0b3ad@nvidia.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 254290869fd234b85119c48dbb98efa5fcd41a31 ]

host1x_device_add looks through the idle clients list to populate
subdevs, and any matches entries are moved from the subdevs list
to the active list. If all subdevs are populated, device_add will
be called on the device. The secondary "subdevs list empty" check
will then incorrectly again call device_add.

However, this would require a convoluted scenario since clients don't
typically end up on the idle clients list.

Fix by checking whether the device was already added before adding
again.

Fixes: fab823d82ee5 ("gpu: host1x: Allow loading tegra-drm without enabled engines")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260609-b4-host1x-small-fixes-a-v1-2-7c1131c0b3ad@nvidia.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

__host1x_bo_unpin() drops the last reference to the mapping and frees
it, so we can't dereference mapping afterwards. The cache itself
outlives the mapping, so use the cache local variable instead.

Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/linux-tegra/ah6ErK6f4kVudVIA@stanley.mountain/T/#u
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260603-host1x-bocache-leak-fix-v1-1-494101dbfd30@nvidia.com

Commit "iommu: return full error code from iommu_map_sg[_atomic]()"
changed iommu_map_sgtable() to return an ssize_t and negative values
in error cases, rather than a size_t and a zero.

pin_job() also was incorrectly assigning to 'int', which could cause
overflows into negative values.

Update pin_job() to correctly check for errors from iommu_map_sgtable.

Fixes: ad8f36e4b6b1 ("iommu: return full error code from iommu_map_sg[_atomic]()")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260421-iommu_map_sgtable-return-v1-1-fb484c07d2a1@nvidia.com

The drivers/gpu/host1x/context_bus.c does not include any declaration of
host1x_context_device_bus_type, and after including "context.h" it also
showed that there are two definitions in the kernel because the extern
declaration was missing the const qualifier.

Include linux/host1x_context_bus.h and drop the wrong declaration from
context.h. While at it, also predeclare struct host1x_memory_context.

Fixes the following sparse warning:

    drivers/gpu/host1x/context_bus.c:9:23: warning: symbol 'host1x_context_device_bus_type' was not declared. Should it be static?

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
[treding@nvidia.com: minor fixups, reword commit message to reflect changes]
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260123140512.609167-1-ben.dooks@codethink.co.uk

After device_initialize(), the embedded struct device in struct
host1x_device should be released through the device core with
put_device().

In host1x_device_add(), if host1x_device_parse_dt() fails, the current
error path frees the object directly with kfree(device). That bypasses
the normal device lifetime handling and leaks the reference held on the
embedded struct device.

The issue was identified by a static analysis tool I developed and
confirmed by manual review.

Fix this by using put_device() in the host1x_device_parse_dt() failure
path.

Fixes: f4c5cf88fbd50 ("gpu: host1x: Provide a proper struct bus_type")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Acked-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260413141526.2961841-1-lgs201920130244@gmail.com

In tegra_mipi_request(), when provider.np is not equal with args.np, it
returns without calling of_node_put(args.np), causing a reference leak.

Convert to use the existing goto out pattern to ensure proper cleanup.

Fixes: 767598d447aa ("gpu: host1x: mipi: Update tegra_mipi_request() to be node based")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260416-mipi-v1-1-9c027175abdf@gmail.com

In host1x_device_init(), the error teardown paths do not check
client->ops before dereferencing it, unlike the forward init paths
which correctly guard with 'client->ops &&'. This can result in a
NULL pointer dereference if client->ops is NULL.

Fix by adding the missing client->ops check in both the teardown
and teardown_late labels.

Signed-off-by: shayderrr <darknessshayder@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260517170456.84927-1-darknessshayder@gmail.com

When the fence list is empty, host1x_intr_update_hw_state()
falls through to host1x_intr_disable_syncpt_intr()
which does two MMIO writes to disable the syncpoint
interrupt and clear its status.

The ISR has already disabled and acked the interrupt
before calling host1x_intr_handle_interrupt(), making
these two writes redundant. Skip the update_hw_state()
call if no fences remain.

Measured Syncpoint wait latency (50000 samples):
  Average latency:   10.6 us  -> 9.4 us
  99.99 pct latency: 51.90 us -> 36.58 us

Signed-off-by: Tanmay Patil <tanmayp@nvidia.com>
Acked-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patch.msgid.link/20260514103153.766343-3-tanmayp@nvidia.com