The mhu_db_channel info is allocated per channel using devm_kzalloc from
mhu_db_mbox_xlate which gets called from mbox_request_channel. However
we are releasing the allocated mhu_db_channel info using plain kfree from
mhu_db_shutdown which is called from mbox_free_channel.
This leads to random crashes when the channel is freed like below one:
Unable to handle kernel paging request at virtual address 0080000400000008
[0080000400000008] address between user and kernel address ranges
Internal error: Oops: 96000044 [#1] PREEMPT SMP
Modules linked in: scmi_module(-)
CPU: 1 PID: 2212 Comm: rmmod Not tainted 5.10.0-rc5 #31
Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno
Development Platform, BIOS EDK II Nov 19 2020
pstate: 20000085 (nzCv daIf -PAN -UAO -TCO BTYPE=--)
pc : release_nodes+0x74/0x230
lr : devres_release_all+0x40/0x68
Call trace:
release_nodes+0x74/0x230
devres_release_all+0x40/0x68
device_release_driver_internal+0x12c/0x1f8
driver_detach+0x58/0xe8
bus_remove_driver+0x64/0xe0
driver_unregister+0x38/0x68
platform_driver_unregister+0x1c/0x28
scmi_driver_exit+0x38/0x44 [scmi_module]
__arm64_sys_delete_module+0x188/0x260
el0_svc_common.constprop.0+0x80/0x1a8
do_el0_svc+0x2c/0x98
el0_sync_handler+0x160/0x168
el0_sync+0x174/0x180
Code: 1400000d eb07009f 54000460 f9400486 (f90004a6)
---[ end trace c55ffd306c140233 ]---
Fix it by replacing kfree with devm_kfree as required.
Fixes: 7002ca237b ("mailbox: arm_mhu: Add ARM MHU doorbell driver")
Reported-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
The MHU drives the signal using a 32-bit register, with all 32 bits
logically ORed together. The MHU provides a set of registers to enable
software to set, clear, and check the status of each of the bits of this
register independently. The use of 32 bits for each interrupt line
enables software to provide more information about the source of the
interrupt. For example, each bit of the register can be associated with
a type of event that can contribute to raising the interrupt.
This patch adds a separate the MHU controller driver for doorbel mode
of operation using the extended DT binding to add support the same.
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>
Sudeep Holla