[ Upstream commit ac9762a74c7ca7cbfcb4c65f5871373653a046ac ]
When probing the open-dice driver with PROVE_LOCKING=y, lockdep
complains that the mutex in 'drvdata->lock' has a non-static key:
| INFO: trying to register non-static key.
| The code is fine but needs lockdep annotation, or maybe
| you didn't initialize this object before use?
| turning off the locking correctness validator.
Fix the problem by initialising the mutex memory with mutex_init()
instead of __MUTEX_INITIALIZER().
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Brazdil <dbrazdil@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20240126152410.10148-1-will@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Open Profile for DICE is an open protocol for measured boot compatible
with the Trusted Computing Group's Device Identifier Composition
Engine (DICE) specification. The generated Compound Device Identifier
(CDI) certificates represent the hardware/software combination measured
by DICE, and can be used for remote attestation and sealing.
Add a driver that exposes reserved memory regions populated by firmware
with DICE CDIs and exposes them to userspace via a character device.
Userspace obtains the memory region's size from read() and calls mmap()
to create a mapping of the memory region in its address space. The
mapping is not allowed to be write+shared, giving userspace a guarantee
that the data were not overwritten by another process.
Userspace can also call write(), which triggers a wipe of the DICE data
by the driver. Because both the kernel and userspace mappings use
write-combine semantics, all clients observe the memory as zeroed after
the syscall has returned.
Cc: Andrew Scull <ascull@google.com>
Cc: Will Deacon <will@kernel.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: David Brazdil <dbrazdil@google.com>
Link: https://lore.kernel.org/r/20220126231237.529308-3-dbrazdil@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
