From 19c2dd5025bbbf2f773e0213da87364191afa5db Mon Sep 17 00:00:00 2001 From: Sameer Pujar Date: Thu, 2 May 2019 18:25:16 +0530 Subject: [PATCH] dmaengine: tegra210-dma: free dma controller in remove() [ Upstream commit f030e419501cb95e961e9ed35c493b5d46a04eca ] Following kernel panic is seen during DMA driver unload->load sequence ========================================================================== Unable to handle kernel paging request at virtual address ffffff8001198880 Internal error: Oops: 86000007 [#1] PREEMPT SMP CPU: 0 PID: 5907 Comm: HwBinder:4123_1 Tainted: G C 4.9.128-tegra-g065839f Hardware name: galen (DT) task: ffffffc3590d1a80 task.stack: ffffffc3d0678000 PC is at 0xffffff8001198880 LR is at of_dma_request_slave_channel+0xd8/0x1f8 pc : [] lr : [] pstate: 60400045 sp : ffffffc3d067b710 x29: ffffffc3d067b710 x28: 000000000000002f x27: ffffff800949e000 x26: ffffff800949e750 x25: ffffff800949e000 x24: ffffffbefe817d84 x23: ffffff8009f77cb0 x22: 0000000000000028 x21: ffffffc3ffda49c8 x20: 0000000000000029 x19: 0000000000000001 x18: ffffffffffffffff x17: 0000000000000000 x16: ffffff80082b66a0 x15: ffffff8009e78250 x14: 000000000000000a x13: 0000000000000038 x12: 0101010101010101 x11: 0000000000000030 x10: 0101010101010101 x9 : fffffffffffffffc x8 : 7f7f7f7f7f7f7f7f x7 : 62ff726b6b64622c x6 : 0000000000008064 x5 : 6400000000000000 x4 : ffffffbefe817c44 x3 : ffffffc3ffda3e08 x2 : ffffff8001198880 x1 : ffffffc3d48323c0 x0 : ffffffc3d067b788 Process HwBinder:4123_1 (pid: 5907, stack limit = 0xffffffc3d0678028) Call trace: [] 0xffffff8001198880 [] dma_request_chan+0x50/0x1f0 [] dma_request_slave_channel+0x28/0x40 [] tegra_alt_pcm_open+0x114/0x170 [] soc_pcm_open+0x10c/0x878 [] snd_pcm_open_substream+0xc0/0x170 [] snd_pcm_open+0xc4/0x240 [] snd_pcm_playback_open+0x58/0x80 [] snd_open+0xb4/0x178 [] chrdev_open+0xb8/0x1d0 [] do_dentry_open+0x214/0x318 [] vfs_open+0x58/0x88 [] do_last+0x450/0xde0 [] path_openat+0xa8/0x368 [] do_filp_open+0x8c/0x110 [] do_sys_open+0x164/0x220 [] compat_SyS_openat+0x3c/0x50 [] el0_svc_naked+0x34/0x38 ---[ end trace 67e6d544e65b5145 ]--- Kernel panic - not syncing: Fatal exception ========================================================================== In device probe(), of_dma_controller_register() registers DMA controller. But when driver is removed, this is not freed. During driver reload this results in data abort and kernel panic. Add of_dma_controller_free() in driver remove path to fix the issue. Fixes: f46b195799b5 ("dmaengine: tegra-adma: Add support for Tegra210 ADMA") Signed-off-by: Sameer Pujar Reviewed-by: Jon Hunter Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin --- drivers/dma/tegra210-adma.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/dma/tegra210-adma.c b/drivers/dma/tegra210-adma.c index b26256f..08b1027 100644 --- a/drivers/dma/tegra210-adma.c +++ b/drivers/dma/tegra210-adma.c @@ -786,6 +786,7 @@ static int tegra_adma_remove(struct platform_device *pdev) struct tegra_adma *tdma = platform_get_drvdata(pdev); int i; + of_dma_controller_free(pdev->dev.of_node); dma_async_device_unregister(&tdma->dma_dev); for (i = 0; i < tdma->nr_channels; ++i) -- 2.7.4