On Tue, Dec 17, 2019 at 09:20:43AM +0000, John Garry wrote: > On 16/12/2019 17:23, John Garry wrote: > > +, - > > > Hi all, > > xinliang <z.liuxinliang@xxxxxxxxxxxxx> is bouncing. We need to get his new > mail address. > > John > > > > > Enabling CONFIG_DEBUG_TEST_DRIVER_REMOVE causes many warns on a system > > with the HIBMC hw: > > > > [ 27.788806] WARNING: CPU: 24 PID: 1 at > > drivers/gpu/drm/drm_gem_vram_helper.c:564 > > bo_driver_move_notify+0x8c/0x98 > > [ 27.798969] Modules linked in: > > [ 27.802018] CPU: 24 PID: 1 Comm: swapper/0 Tainted: G B > > 5.5.0-rc1-dirty #565 > > [ 27.810358] Hardware name: Huawei D06 /D06, BIOS Hisilicon D06 UEFI > > RC0 - V1.16.01 03/15/2019 > > [ 27.818872] pstate: 20c00009 (nzCv daif +PAN +UAO) > > [ 27.823654] pc : bo_driver_move_notify+0x8c/0x98 > > [ 27.828262] lr : bo_driver_move_notify+0x40/0x98 > > [ 27.832868] sp : ffff00236f0677e0 > > [ 27.836173] x29: ffff00236f0677e0 x28: ffffa0001454e5e0 > > [ 27.841476] x27: ffff002366e52128 x26: ffffa000149e67b0 > > [ 27.846779] x25: ffff002366e523e0 x24: ffff002336936120 > > [ 27.852082] x23: ffff0023346f4010 x22: ffff002336936128 > > [ 27.857385] x21: ffffa000149c15c0 x20: ffff0023369361f8 > > [ 27.862687] x19: ffff002336936000 x18: 0000000000001258 > > [ 27.867989] x17: 0000000000001190 x16: 00000000000011d0 > > [ 27.873292] x15: 0000000000001348 x14: ffffa00012d68190 > > [ 27.878595] x13: 0000000000000006 x12: 1ffff40003241f91 > > [ 27.883897] x11: ffff940003241f91 x10: dfffa00000000000 > > [ 27.889200] x9 : ffff940003241f92 x8 : 0000000000000001 > > [ 27.894502] x7 : ffffa0001920fc88 x6 : ffff940003241f92 > > [ 27.899804] x5 : ffff940003241f92 x4 : ffff0023369363a0 > > [ 27.905107] x3 : ffffa00010c104b8 x2 : dfffa00000000000 > > [ 27.910409] x1 : 0000000000000003 x0 : 0000000000000001 > > [ 27.915712] Call trace: > > [ 27.918151] bo_driver_move_notify+0x8c/0x98 > > [ 27.922412] ttm_bo_cleanup_memtype_use+0x54/0x100 > > [ 27.927194] ttm_bo_put+0x3a0/0x5d0 > > [ 27.930673] drm_gem_vram_object_free+0xc/0x18 > > [ 27.935109] drm_gem_object_free+0x34/0xd0 > > [ 27.939196] drm_gem_object_put_unlocked+0xc8/0xf0 > > [ 27.943978] hibmc_user_framebuffer_destroy+0x20/0x40 > > [ 27.949020] drm_framebuffer_free+0x48/0x58 > > [ 27.953194] drm_mode_object_put.part.1+0x90/0xe8 > > [ 27.957889] drm_mode_object_put+0x28/0x38 > > [ 27.961976] hibmc_fbdev_fini+0x54/0x78 > > [ 27.965802] hibmc_unload+0x2c/0xd0 > > [ 27.969281] hibmc_pci_remove+0x2c/0x40 > > [ 27.973109] pci_device_remove+0x6c/0x140 > > [ 27.977110] really_probe+0x174/0x548 > > [ 27.980763] driver_probe_device+0x7c/0x148 > > [ 27.984936] device_driver_attach+0x94/0xa0 > > [ 27.989109] __driver_attach+0xa8/0x110 > > [ 27.992935] bus_for_each_dev+0xe8/0x158 > > [ 27.996849] driver_attach+0x30/0x40 > > [ 28.000415] bus_add_driver+0x234/0x2f0 > > [ 28.004241] driver_register+0xbc/0x1d0 > > [ 28.008067] __pci_register_driver+0xbc/0xd0 > > [ 28.012329] hibmc_pci_driver_init+0x20/0x28 > > [ 28.016590] do_one_initcall+0xb4/0x254 > > [ 28.020417] kernel_init_freeable+0x27c/0x328 > > [ 28.024765] kernel_init+0x10/0x118 > > [ 28.028245] ret_from_fork+0x10/0x18 > > [ 28.031813] ---[ end trace 35a83b71b657878d ]--- > > [ 28.036503] ------------[ cut here ]------------ > > [ 28.041115] WARNING: CPU: 24 PID: 1 at > > drivers/gpu/drm/drm_gem_vram_helper.c:40 > > ttm_buffer_object_destroy+0x4c/0x80 > > [ 28.051537] Modules linked in: > > [ 28.054585] CPU: 24 PID: 1 Comm: swapper/0 Tainted: G B W > > 5.5.0-rc1-dirty #565 > > [ 28.062924] Hardware name: Huawei D06 /D06, BIOS Hisilicon D06 UEFI > > RC0 - V1.16.01 03/15/2019 > > > > [snip] > > > > Indeed, simply unbinding the device from the driver causes the same sort > > of issue: > > > > root@(none)$ cd ./bus/pci/drivers/hibmc-drm/ > > root@(none)$ ls > > 0000:05:00.0 bind new_id remove_id uevent > > unbind > > root@(none)$ echo 0000\:05\:00.0 > unbind > > [ 116.074352] ------------[ cut here ]------------ > > [ 116.078978] WARNING: CPU: 17 PID: 1178 at > > drivers/gpu/drm/drm_gem_vram_helper.c:40 > > ttm_buffer_object_destroy+0x4c/0x80 > > [ 116.089661] Modules linked in: > > [ 116.092711] CPU: 17 PID: 1178 Comm: sh Tainted: G B W > > 5.5.0-rc1-dirty #565 > > [ 116.100704] Hardware name: Huawei D06 /D06, BIOS Hisilicon D06 UEFI > > RC0 - V1.16.01 03/15/2019 > > [ 116.109218] pstate: 20400009 (nzCv daif +PAN -UAO) > > [ 116.114001] pc : ttm_buffer_object_destroy+0x4c/0x80 > > [ 116.118956] lr : ttm_buffer_object_destroy+0x18/0x80 > > [ 116.123910] sp : ffff0022e6cef8e0 > > [ 116.127215] x29: ffff0022e6cef8e0 x28: ffff00231b1fb000 > > [ 116.132519] x27: 0000000000000000 x26: ffff00231b1fb000 > > [ 116.137821] x25: ffff0022e6cefdc0 x24: 0000000000002480 > > [ 116.143124] x23: ffff0023682b6ab0 x22: ffff0023682b6800 > > [ 116.148427] x21: ffff0023682b6800 x20: 0000000000000000 > > [ 116.153730] x19: ffff0023682b6800 x18: 0000000000000000 > > [ 116.159032] x17: 000000000000000000000000001 > > [ 116.185545] x7 : ffff0023682b6b07 x6 : ffff80046d056d61 > > [ 116.190848] x5 : ffff80046d056d61 x4 : ffff0023682b6ba0 > > [ 116.196151] x3 : ffffa00010197338 x2 : dfffa00000000000 > > [ 116.201453] x1 : 0000000000000003 x0 : 0000000000000001 > > [ 116.206756] Call trace: > > [ 116.209195] ttm_buffer_object_destroy+0x4c/0x80 > > [ 116.213803] ttm_bo_release_list+0x184/0x220 > > [ 116.218064] ttm_bo_put+0x410/0x5d0 > > [ 116.221544] drm_gem_vram_object_free+0xc/0x18 > > [ 116.225979] drm_gem_object_free+0x34/0xd0 > > [ 116.230066] drm_gem_object_put_unlocked+0xc8/0xf0 > > [ 116.234848] hibmc_user_framebuffer_destroy+0x20/0x40 > > [ 116.239890] drm_framebuffer_free+0x48/0x58 > > [ 116.244064] drm_mode_object_put.part.1+0x90/0xe8 > > [ 116.248759] drm_mode_object_put+0x28/0x38 > > [ 116.252846] hibmc_fbdev_fini+0x54/0x78 > > [ 116.256672] hibmc_unload+0x2c/0xd0 > > [ 116.260151] hibmc_pci_remove+0x2c/0x40 > > [ 116.263979] pci_device_remove+0x6c/0x140 > > [ 116.267980] device_release_driver_internal+0x134/0x250 > > [ 116.273196] device_driver_detach+0x28/0x38 > > [ 116.277369] unbind_store+0xfc/0x150 > > [ 116.280934] drv_attr_store+0x48/0x60 > > [ 116.284589] sysfs_kf_write+0x80/0xb0 > > [ 116.288241] kernfs_fop_write+0x1d4/0x320 > > [ 116.292243] __vfs_write+0x54/0x98 > > [ 116.295635] vfs_write+0xe8/0x270 > > [ 116.298940] ksys_write+0xc8/0x180 > > [ 116.302333] __arm64_sys_write+0x40/0x50 > > [ 116.306248] el0_svc_common.constprop.0+0xa4/0x1f8 > > [ 116.311029] el0_svc_handler+0x34/0xb0 > > [ 116.314770] el0_sync_handler+0x10c/0x1c8 > > [ 116.318769] el0_sync+0x140/0x180 > > [ 116.322074] ---[ end trace e60e43d0e316b5c8 ]--- > > [ 116.326868] ------------[ cut here ]------------ > > > > > > dmesg and .config is here: > > https://pastebin.com/4P5yaZBS > > > > I'm not sure if this is a HIBMC driver issue or issue with the framework. Display-only drivers shouldn't go boom like this, the drm framework is fixed for those. Unfortunately there's still many drivers that get their unload sequence and resource refcounting totally wrong. For a start see devm_drm_dev_init() and related documentation for recommendations for current best practices: https://dri.freedesktop.org/docs/drm/gpu/drm-internals.html#display-driver-example Cheers, Daniel > > > > john > > > > > -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
