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 v2: - Add a 'available_gpu' bool variable to indicate that an available "vivante,gc" has been found

drivers/gpu/drm/etnaviv/etnaviv_drv.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c index ac23c0f..9044bf9 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c @@ -632,6 +632,7 @@ static struct platform_driver etnaviv_platform_driver = { };

static struct platform_device *etnaviv_drm; +static bool available_gpu;

static int __init etnaviv_init(void) { @@ -655,6 +656,7 @@ static int __init etnaviv_init(void) for_each_compatible_node(np, NULL, "vivante,gc") { if (!of_device_is_available(np)) continue; + available_gpu = true; etnaviv_drm = platform_device_register_simple("etnaviv", -1, NULL, 0); if (IS_ERR(etnaviv_drm)) { @@ -677,8 +679,10 @@ module_init(etnaviv_init);

static void __exit etnaviv_exit(void) { - platform_driver_unregister(&etnaviv_gpu_driver); + if (available_gpu) + platform_device_unregister(etnaviv_drm); platform_driver_unregister(&etnaviv_platform_driver); + platform_driver_unregister(&etnaviv_gpu_driver); } module_exit(etnaviv_exit);

On Mon, 2018-06-25 at 16:16 -0300, Fabio Estevam wrote:

From: Fabio Estevam fabio.estevam@nxp.com

platform_device_register_simple() may fail, so we should better check its return value and propagate it in the case of error.

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

---

Changes since v2:

• Newly introduced in this version

drivers/gpu/drm/etnaviv/etnaviv_drv.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c index e5013a9..ac23c0f 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; @@ -644,7 +646,7 @@ static int __init etnaviv_init(void) ret = platform_driver_register(&etnaviv_platform_driver); if (ret != 0)

• platform_driver_unregister(&etnaviv_gpu_driver);
  

• goto unregister_gpu_driver;
  

/* * If the DT contains at least one available GPU device, instantiate @@ -653,12 +655,22 @@ static int __init etnaviv_init(void) for_each_compatible_node(np, NULL, "vivante,gc") { 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);
  

Rather than store the error value in the global variable, I'd use a local variable here and only set etnaviv_drm if this doesn't fail.

• if (IS_ERR(etnaviv_drm)) {
  

• 	ret = PTR_ERR(etnaviv_drm);
  

• 	goto unregister_platform_driver;
  

• }
  

  of_node_put(np); break;

Ah, focusing on etnaviv_exit last time I've completely overlooked this break.

}

• return 0;

+unregister_platform_driver:

• platform_driver_unregister(&etnaviv_platform_driver);

+unregister_gpu_driver:

• platform_driver_unregister(&etnaviv_gpu_driver); return ret;

} module_init(etnaviv_init);