Hi Fabio,

On Sun, 2018-06-24 at 19:40 -0300, Fabio Estevam wrote:

From: Fabio Estevam fabio.estevam@nxp.com

Russell King reported:

"When removing and reloading the etnaviv module, the following splat occurs:

sysfs: cannot create duplicate filename '/devices/platform/etnaviv' CPU: 0 PID: 1471 Comm: modprobe Not tainted 4.17.0+ #1608 Hardware name: Marvell Dove (Cubox) Backtrace: [<c00157d4>] (dump_backtrace) from [<c0015b8c>] (show_stack+0x18/0x1c) r6:ef033e38 r5:ee07b340 r4:edb9d000 r3:00000000 [<c0015b74>] (show_stack) from [<c0620784>] (dump_stack+0x20/0x28) [<c0620764>] (dump_stack) from [<c01bcd24>] (sysfs_warn_dup+0x5c/0x70) [<c01bccc8>] (sysfs_warn_dup) from [<c01bce14>] (sysfs_create_dir_ns+0x90/0x98) ..."

Commit 246774d17fc0 ("drm/etnaviv: remove the need for a gpu-subsystem DT node") introduced DRM registration via platform_device_register_simple(), but missed to call platform_device_unregister() inside etnaviv_exit().

Fix the problem by calling platform_device_unregister() inside etnaviv_exit(). While at it, also rearrange the function calls in the exit path to make them happen in the opposite order of registration.

Tested on a imx6-sabresd board.

Cc: stable@vger.kernel.org Fixes: 246774d17fc0 ("drm/etnaviv: remove the need for a gpu-subsystem DT node") Reported-by: Russell King linux@armlinux.org.uk Signed-off-by: Fabio Estevam fabio.estevam@nxp.com

---

Changes since v1:

• Make the exit path symmetrical to the init path by calling

platform_device_unregister() inside for_each_compatible_node()

drivers/gpu/drm/etnaviv/etnaviv_drv.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c index e5013a9..626ad8b 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c @@ -631,6 +631,8 @@ static struct platform_driver etnaviv_platform_driver = { }, }; +static struct platform_device *etnaviv_drm;

static int __init etnaviv_init(void) { int ret; @@ -654,7 +656,8 @@ static int __init etnaviv_init(void) if (!of_device_is_available(np)) continue;

• platform_device_register_simple("etnaviv", -1, NULL, 0);
  

• etnaviv_drm = platform_device_register_simple("etnaviv", -1,
  

• 					      NULL, 0);
  

If there are multiple vivante,gc device nodes, this overwrites etnaviv_drm with each additional device after the first one.

Also, it would be better to store NULL instead of the error value.

of_node_put(np);
break;

} @@ -665,8 +668,19 @@ module_init(etnaviv_init); static void __exit etnaviv_exit(void) {

• platform_driver_unregister(&etnaviv_gpu_driver);

• struct device_node *np;
• for_each_compatible_node(np, NULL, "vivante,gc") {

• if (!of_device_is_available(np))
  

• 	continue;
  

• platform_device_unregister(etnaviv_drm);
  

If there are multiple vivante,gc nodes, this will try to unregister the last device multiple times. Also, this will break if the pointer contains an error value.

• of_node_put(np);
  

• break;
  

• }
• platform_driver_unregister(&etnaviv_platform_driver);
• platform_driver_unregister(&etnaviv_gpu_driver);

} module_exit(etnaviv_exit);

regards Philipp