Mainak Sen 4e6e07ce01 gpu: host1x: Fix race in syncpt alloc/free ...

[ Upstream commit c7d393267c ]

Fix race condition between host1x_syncpt_alloc()
and host1x_syncpt_put() by using kref_put_mutex()
instead of kref_put() + manual mutex locking.

This ensures no thread can acquire the
syncpt_mutex after the refcount drops to zero
but before syncpt_release acquires it.
This prevents races where syncpoints could
be allocated while still being cleaned up
from a previous release.

Remove explicit mutex locking in syncpt_release
as kref_put_mutex() handles this atomically.

Signed-off-by: Mainak Sen <msen@nvidia.com>
Fixes: f5ba33fb96 ("gpu: host1x: Reserve VBLANK syncpoints at initialization")
Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20250707-host1x-syncpt-race-fix-v1-1-28b0776e70bc@nvidia.com
Signed-off-by: Sasha Levin <sashal@kernel.org>

2025-12-18 13:54:40 +01:00

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hw

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bus.c

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bus.h

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cdma.c

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cdma.h

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channel.c

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channel.h

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context_bus.c

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context.c

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context.h

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debug.c

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debug.h

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dev.c

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dev.h

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fence.c

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fence.h

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intr.c

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intr.h

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job.c

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job.h

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Kconfig

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Makefile

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mipi.c

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syncpt.c

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syncpt.h

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