Commits
Grygorii Strashko committed 213fa10db2f
ARM: OMAP2+: omap_device: fix crash on omap_device removal Below call chain causes system crash when OMAP device is removed by calling of_platform_depopulate()/device_del(): device_del() - blocking_notifier_call_chain(&dev->bus->p->bus_notifier, BUS_NOTIFY_DEL_DEVICE, dev); - _omap_device_notifier_call() - omap_device_delete() - od->pdev->archdata.od = NULL; kfree(od->hwmods); kfree(od); - bus_remove_device() - device_release_driver() - __device_release_driver() - pm_runtime_get_sync() - _od_runtime_resume() - omap_hwmod_enable() <- OOPS od's delted already Backtrace: Unable to handle kernel NULL pointer dereference at virtual address 0000000d pgd = eb100000 [0000000d] *pgd=ad6e1831, *pte=00000000, *ppte=00000000 Internal error: Oops: 17 [#1] PREEMPT SMP ARM CPU: 1 PID: 1273 Comm: modprobe Not tainted 4.4.15-rt19-00115-ge4d3cd3-dirty #68 Hardware name: Generic DRA74X (Flattened Device Tree) task: eb1ee800 ti: ec962000 task.ti: ec962000 PC is at omap_device_enable+0x10/0x90 LR is at _od_runtime_resume+0x10/0x24 [...] [<c00299dc>] (omap_device_enable) from [<c0029a6c>] (_od_runtime_resume+0x10/0x24) [<c0029a6c>] (_od_runtime_resume) from [<c04ad404>] (__rpm_callback+0x20/0x34) [<c04ad404>] (__rpm_callback) from [<c04ad438>] (rpm_callback+0x20/0x80) [<c04ad438>] (rpm_callback) from [<c04aee28>] (rpm_resume+0x48c/0x964) [<c04aee28>] (rpm_resume) from [<c04af360>] (__pm_runtime_resume+0x60/0x88) [<c04af360>] (__pm_runtime_resume) from [<c04a4974>] (__device_release_driver+0x30/0x100) [<c04a4974>] (__device_release_driver) from [<c04a4a60>] (device_release_driver+0x1c/0x28) [<c04a4a60>] (device_release_driver) from [<c04a38c0>] (bus_remove_device+0xec/0x144) [<c04a38c0>] (bus_remove_device) from [<c04a0764>] (device_del+0x10c/0x210) [<c04a0764>] (device_del) from [<c04a67b0>] (platform_device_del+0x18/0x84) [<c04a67b0>] (platform_device_del) from [<c04a6828>] (platform_device_unregister+0xc/0x20) [<c04a6828>] (platform_device_unregister) from [<c05adcfc>] (of_platform_device_destroy+0x8c/0x90) [<c05adcfc>] (of_platform_device_destroy) from [<c04a02f0>] (device_for_each_child+0x4c/0x78) [<c04a02f0>] (device_for_each_child) from [<c05adc5c>] (of_platform_depopulate+0x30/0x44) [<c05adc5c>] (of_platform_depopulate) from [<bf123920>] (cpsw_remove+0x68/0xf4 [ti_cpsw]) [<bf123920>] (cpsw_remove [ti_cpsw]) from [<c04a68d8>] (platform_drv_remove+0x24/0x3c) [<c04a68d8>] (platform_drv_remove) from [<c04a49c8>] (__device_release_driver+0x84/0x100) [<c04a49c8>] (__device_release_driver) from [<c04a4b20>] (driver_detach+0xac/0xb0) [<c04a4b20>] (driver_detach) from [<c04a3be8>] (bus_remove_driver+0x60/0xd4) [<c04a3be8>] (bus_remove_driver) from [<c00d9870>] (SyS_delete_module+0x184/0x20c) [<c00d9870>] (SyS_delete_module) from [<c0010540>] (ret_fast_syscall+0x0/0x1c) Code: e3500000 e92d4070 1590630c 01a06000 (e5d6300d) Hence, fix it by using BUS_NOTIFY_REMOVED_DEVICE event for OMAP device deletion which is sent when DD has finished processing of device deletion. Cc: Tony Lindgren <tony@atomide.com> Cc: Tero Kristo <t-kristo@ti.com> Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: David S. Miller <davem@davemloft.net>