commit 7378aeb664 upstream.
In the rproc_alloc() function, on error, put_device(&rproc->dev) is
called, leading to the call of the rproc_type_release() function.
An error can occurs before ida_alloc is called.
In such case in rproc_type_release(), the condition (rproc->index >= 0) is
true as rproc->index has been initialized to 0.
ida_free() is called reporting a warning:
[ 4.181906] WARNING: CPU: 1 PID: 24 at lib/idr.c:525 ida_free+0x100/0x164
[ 4.186378] stm32-display-dsi 5a000000.dsi: Fixed dependency cycle(s) with /soc/dsi@5a000000/panel@0
[ 4.188854] ida_free called for id=0 which is not allocated.
[ 4.198256] mipi-dsi 5a000000.dsi.0: Fixed dependency cycle(s) with /soc/dsi@5a000000
[ 4.203556] Modules linked in: panel_orisetech_otm8009a dw_mipi_dsi_stm(+) gpu_sched dw_mipi_dsi stm32_rproc stm32_crc32 stm32_ipcc(+) optee(+)
[ 4.224307] CPU: 1 UID: 0 PID: 24 Comm: kworker/u10:0 Not tainted 6.12.0 #442
[ 4.231481] Hardware name: STM32 (Device Tree Support)
[ 4.236627] Workqueue: events_unbound deferred_probe_work_func
[ 4.242504] Call trace:
[ 4.242522] unwind_backtrace from show_stack+0x10/0x14
[ 4.250218] show_stack from dump_stack_lvl+0x50/0x64
[ 4.255274] dump_stack_lvl from __warn+0x80/0x12c
[ 4.260134] __warn from warn_slowpath_fmt+0x114/0x188
[ 4.265199] warn_slowpath_fmt from ida_free+0x100/0x164
[ 4.270565] ida_free from rproc_type_release+0x38/0x60
[ 4.275832] rproc_type_release from device_release+0x30/0xa0
[ 4.281601] device_release from kobject_put+0xc4/0x294
[ 4.286762] kobject_put from rproc_alloc.part.0+0x208/0x28c
[ 4.292430] rproc_alloc.part.0 from devm_rproc_alloc+0x80/0xc4
[ 4.298393] devm_rproc_alloc from stm32_rproc_probe+0xd0/0x844 [stm32_rproc]
[ 4.305575] stm32_rproc_probe [stm32_rproc] from platform_probe+0x5c/0xbc
Calling ida_alloc earlier in rproc_alloc ensures that the rproc->index is
properly set.
Fixes: 08333b911f ("remoteproc: Directly use ida_alloc()/free()")
Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20241122175127.2188037-1-arnaud.pouliquen@foss.st.com
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
b32d60a852