remoteproc: core: Fix ida_free call while not allocated

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: 08333b911f01 ("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>

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index eb66f78ec8b7747f6fa9fd023259aa3566d5f098..c2cf0d277729664792f20416f4aad21dadef5c46 100644 (file)
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -2486,6 +2486,13 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
        rproc->dev.driver_data = rproc;
        idr_init(&rproc->notifyids);
 
+       /* Assign a unique device index and name */
+       rproc->index = ida_alloc(&rproc_dev_index, GFP_KERNEL);
+       if (rproc->index < 0) {
+               dev_err(dev, "ida_alloc failed: %d\n", rproc->index);
+               goto put_device;
+       }
+
        rproc->name = kstrdup_const(name, GFP_KERNEL);
        if (!rproc->name)
                goto put_device;
@@ -2496,13 +2503,6 @@ struct rproc *rproc_alloc(struct device *dev, const char *name,
        if (rproc_alloc_ops(rproc, ops))
                goto put_device;
 
-       /* Assign a unique device index and name */
-       rproc->index = ida_alloc(&rproc_dev_index, GFP_KERNEL);
-       if (rproc->index < 0) {
-               dev_err(dev, "ida_alloc failed: %d\n", rproc->index);
-               goto put_device;
-       }
-
        dev_set_name(&rproc->dev, "remoteproc%d", rproc->index);
 
        atomic_set(&rproc->power, 0);