firmware: arm_ffa: Change initcall level of ffa_init() to rootfs_initcall

The Linux IMA (Integrity Measurement Architecture) subsystem used for
secure boot, file integrity, or remote attestation can

firmware: arm_ffa: Change initcall level of ffa_init() to rootfs_initcall

The Linux IMA (Integrity Measurement Architecture) subsystem used for
secure boot, file integrity, or remote attestation cannot be a loadable
module for few reasons listed below:

o Boot-Time Integrity: IMA’s main role is to measure and appraise files
before they are used. This includes measuring critical system files during
early boot (e.g., init, init scripts, login binaries). If IMA were a
module, it would be loaded too late to cover those.

o TPM Dependency: IMA integrates tightly with the TPM to record
measurements into PCRs. The TPM must be initialized early (ideally before
init_ima()), which aligns with IMA being built-in.

o Security Model: IMA is part of a Trusted Computing Base (TCB). Making it
a module would weaken the security model, as a potentially compromised
system could delay or tamper with its initialization.

IMA must be built-in to ensure it starts measuring from the earliest
possible point in boot which inturn implies TPM must be initialised and
ready to use before IMA.

To enable integration of tpm_event_log with the IMA subsystem, the TPM
drivers (tpm_crb and tpm_crb_ffa) also needs to be built-in. However with
FF-A driver also being initialised at device initcall level, it can lead to
an initialization order issue where:
- crb_acpi_driver_init() may run before tpm_crb_ffa_driver()_init and
ffa_init()
- As a result, probing the TPM device via CRB over FFA is deferred
- ima_init() (called as a late initcall) runs before deferred probe
completes, IMA fails to find the TPM and logs the below error:

| ima: No TPM chip found, activating TPM-bypass!

Eventually it fails to generate boot_aggregate with PCR values.

Because of the above stated dependency, the ffa driver needs to initialised
before tpm_crb_ffa module to ensure IMA finds the TPM successfully when
present.

[ jarkko: reformatted some of the paragraphs because they were going past
the 75 character boundary. ]

Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>

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firmware: arm_ffa: Replace mutex with rwlock to avoid sleep in atomic context

The current use of a mutex to protect the notifier hashtable accesses
can lead to issues in the atomic context. It resul

firmware: arm_ffa: Replace mutex with rwlock to avoid sleep in atomic context

The current use of a mutex to protect the notifier hashtable accesses
can lead to issues in the atomic context. It results in the below
kernel warnings:

| BUG: sleeping function called from invalid context at kernel/locking/mutex.c:258
| in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 9, name: kworker/0:0
| preempt_count: 1, expected: 0
| RCU nest depth: 0, expected: 0
| CPU: 0 UID: 0 PID: 9 Comm: kworker/0:0 Not tainted 6.14.0 #4
| Workqueue: ffa_pcpu_irq_notification notif_pcpu_irq_work_fn
| Call trace:
| show_stack+0x18/0x24 (C)
| dump_stack_lvl+0x78/0x90
| dump_stack+0x18/0x24
| __might_resched+0x114/0x170
| __might_sleep+0x48/0x98
| mutex_lock+0x24/0x80
| handle_notif_callbacks+0x54/0xe0
| notif_get_and_handle+0x40/0x88
| generic_exec_single+0x80/0xc0
| smp_call_function_single+0xfc/0x1a0
| notif_pcpu_irq_work_fn+0x2c/0x38
| process_one_work+0x14c/0x2b4
| worker_thread+0x2e4/0x3e0
| kthread+0x13c/0x210
| ret_from_fork+0x10/0x20

To address this, replace the mutex with an rwlock to protect the notifier
hashtable accesses. This ensures that read-side locking does not sleep and
multiple readers can acquire the lock concurrently, avoiding unnecessary
contention and potential deadlocks. Writer access remains exclusive,
preserving correctness.

This change resolves warnings from lockdep about potential sleep in
atomic context.

Cc: Jens Wiklander <jens.wiklander@linaro.org>
Reported-by: Jérôme Forissier <jerome.forissier@linaro.org>
Closes: https://github.com/OP-TEE/optee_os/issues/7394
Fixes: e0573444edbf ("firmware: arm_ffa: Add interfaces to request notification callbacks")
Message-Id: <20250528-ffa_notif_fix-v1-3-5ed7bc7f8437@arm.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Tested-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

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firmware: arm_ffa: Move memory allocation outside the mutex locking

The notifier callback node allocation is currently done while holding
the notify_lock mutex. While this is safe even if memory all

firmware: arm_ffa: Move memory allocation outside the mutex locking

The notifier callback node allocation is currently done while holding
the notify_lock mutex. While this is safe even if memory allocation may
sleep, we need to move the allocation outside the locked region in
preparation to move from using muxtes to rwlocks.

Move the memory allocation to avoid potential sleeping in atomic context
once the locks are moved from mutex to rwlocks.

Fixes: e0573444edbf ("firmware: arm_ffa: Add interfaces to request notification callbacks")
Message-Id: <20250528-ffa_notif_fix-v1-2-5ed7bc7f8437@arm.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

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firmware: arm_ffa: Fix memory leak by freeing notifier callback node

Commit e0573444edbf ("firmware: arm_ffa: Add interfaces to request
notification callbacks") adds support for notifier callbacks b

firmware: arm_ffa: Fix memory leak by freeing notifier callback node

Commit e0573444edbf ("firmware: arm_ffa: Add interfaces to request
notification callbacks") adds support for notifier callbacks by allocating
and inserting a callback node into a hashtable during registration of
notifiers. However, during unregistration, the code only removes the
node from the hashtable without freeing the associated memory, resulting
in a memory leak.

Resolve the memory leak issue by ensuring the allocated notifier callback
node is properly freed after it is removed from the hashtable entry.

Fixes: e0573444edbf ("firmware: arm_ffa: Add interfaces to request notification callbacks")
Message-Id: <20250528-ffa_notif_fix-v1-1-5ed7bc7f8437@arm.com>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

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