[PATCH 5.4 268/344] remoteproc: Initialize rproc_class before use

Greg Kroah-Hartman
2020-02-21T08:12:51Z

From: Brandon Maier <brandon.maier@rockwellcollins.com>

[ Upstream commit a8f40111d184098cd2b3dc0c7170c42250a5fa09 ]

The remoteproc_core and remoteproc drivers all initialize with module_init().
However remoteproc drivers need the rproc_class during their probe. If one of
the remoteproc drivers runs init and gets through probe before
remoteproc_init() runs, a NULL pointer access of rproc_class's `glue_dirs`
spinlock occurs.

> Unable to handle kernel NULL pointer dereference at virtual address 000000dc
> pgd = c0004000
> [000000dc] *pgd=00000000
> Internal error: Oops: 5 [#1] PREEMPT ARM
> Modules linked in:
> CPU: 0 PID: 1 Comm: swapper Tainted: G W 4.14.106-rt56 #1
> Hardware name: Generic OMAP36xx (Flattened Device Tree)
> task: c6050000 task.stack: c604a000
> PC is at rt_spin_lock+0x40/0x6c
> LR is at rt_spin_lock+0x28/0x6c
> pc : [<c0523c90>] lr : [<c0523c78>] psr: 60000013
> sp : c604bdc0 ip : 00000000 fp : 00000000
> r10: 00000000 r9 : c61c7c10 r8 : c6269c20
> r7 : c0905888 r6 : c6269c20 r5 : 00000000 r4 : 000000d4
> r3 : 000000dc r2 : c6050000 r1 : 00000002 r0 : 000000d4
> Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
...
> [<c0523c90>] (rt_spin_lock) from [<c03b65a4>] (get_device_parent+0x54/0x17c)
> [<c03b65a4>] (get_device_parent) from [<c03b6bec>] (device_add+0xe0/0x5b4)
> [<c03b6bec>] (device_add) from [<c042adf4>] (rproc_add+0x18/0xd8)
> [<c042adf4>] (rproc_add) from [<c01110e4>] (my_rproc_probe+0x158/0x204)
> [<c01110e4>] (my_rproc_probe) from [<c03bb6b8>] (platform_drv_probe+0x34/0x70)
> [<c03bb6b8>] (platform_drv_probe) from [<c03b9dd4>] (driver_probe_device+0x2c8/0x420)
> [<c03b9dd4>] (driver_probe_device) from [<c03ba02c>] (__driver_attach+0x100/0x11c)
> [<c03ba02c>] (__driver_attach) from [<c03b7d08>] (bus_for_each_dev+0x7c/0xc0)
> [<c03b7d08>] (bus_for_each_dev) from [<c03b910c>] (bus_add_driver+0x1cc/0x264)
> [<c03b910c>] (bus_add_driver) from [<c03ba714>] (driver_register+0x78/0xf8)
> [<c03ba714>] (driver_register) from [<c010181c>] (do_one_initcall+0x100/0x190)
> [<c010181c>] (do_one_initcall) from [<c0800de8>] (kernel_init_freeable+0x130/0x1d0)
> [<c0800de8>] (kernel_init_freeable) from [<c051eee8>] (kernel_init+0x8/0x114)
> [<c051eee8>] (kernel_init) from [<c01175b0>] (ret_from_fork+0x14/0x24)
> Code: e2843008 e3c2203f f5d3f000 e5922010 (e193cf9f)
> ---[ end trace 0000000000000002 ]---

Signed-off-by: Brandon Maier <brandon.maier@rockwellcollins.com>
Link: https://lore.kernel.org/r/20190530225223.136420-1-brandon.maier@rockwellcollins.com
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/remoteproc/remoteproc_core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 3c5fbbbfb0f17..b542debbc6f03 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -2224,7 +2224,7 @@ static int __init remoteproc_init(void)

return 0;
}
-module_init(remoteproc_init);
+subsys_initcall(remoteproc_init);

static void __exit remoteproc_exit(void)
{
--
2.20.1