https://bugzilla.kernel.org/show_bug.cgi?id=195729 --- Comment #1 from jqiaoulk@xxxxxxxxx --- It tells us that clk_set_parent() will potentially goes to sleep under some circumstances(in this case, to acquire the mutex lock). Therefore,with regard to the Driver caller routine shown below, it must incorrect runs in critical section, which possible call spin_lock() or other related functions which disable the preemption. Since it is not in the IRQ context, it is very likely spink lock is called in this failure case. Looking into the Driver code, should give the clue. [Fri May 05 05:26:09.992 2017] [40636.613352] [<7eea79ec>] (vibe_os_clk_set_parent+0x34/0xb0 [vibe_os]) from [<7eec3cd0>] (_ZN12CSTmClockLLA6EnableE29stm_clk_divider_output_name_t31stm_clk_divider_output_source_t31stm_clk_divider_output_divide_t+0xd4/0xf0 [stmcore_display_stiH407]) [Fri May 05 05:26:10.017 2017] [40636.635408] [<7eec3cd0>] (_ZN12CSTmClockLLA6EnableE29stm_clk_divider_output_name_t31stm_clk_divider_output_source_t31stm_clk_divider_output_divide_t+0xd4/0xf0 [stmcore_display_stiH407]) from [<7eec8c2c>] (_ZN16CSTmMainTVOutput15SetOutputFormatEj+0xc8/0x1b0 [stmcore_display_stiH407]) [Fri May 05 05:26:10.036 2017] [40636.660506] [<7eec8c2c>] (_ZN16CSTmMainTVOutput15SetOutputFormatEj+0xc8/0x1b0 [stmcore_display_stiH407]) from [<7eebbd40>] (_ZN16CSTmMasterOutput5StartEPK18stm_display_mode_s+0x1b8/0x1f8 [stmcore_display_stiH407]) [Fri May 05 05:26:10.069 2017] [40636.679522] [<7eebbd40>] (_ZN16CSTmMasterOutput5StartEPK18stm_display_mode_s+0x1b8/0x1f8 [stmcore_display_stiH407]) from [<7eeba0ac>] (stm_display_output_start+0x6c/0xb4 [stmcore_display_stiH407]) [Fri May 05 05:26:10.069 2017] [40636.697123] [<7eeba0ac>] (stm_display_output_start+0x6c/0xb4 [stmcore_display_stiH407]) from [<7f444650>] (dil_blender_output_start+0x8c/0x17c [stm_cdi_dvb]) [Fri May 05 05:26:10.079 2017] [40636.711321] [<7f444650>] (dil_blender_output_start+0x8c/0x17c [stm_cdi_dvb]) from [<7f45717c>] (cdi_hdmi_exit+0xb64/0xbc4 [stm_cdi_dvb]) [Fri May 05 05:26:10.092 2017] [40636.723660] [<7f45717c>] (cdi_hdmi_exit+0xb64/0xbc4 [stm_cdi_dvb]) from [<7f4578a4>] (dil_hdmi_set_video_code+0x4c/0x1d4 [stm_cdi_dvb]) [Fri May 05 05:26:10.104 2017] [40636.735912] [<7f4578a4>] (dil_hdmi_set_video_code+0x4c/0x1d4 [stm_cdi_dvb]) from [<7f44ed74>] (hdmi_release+0x316c/0x781c [stm_cdi_dvb]) [Fri May 05 05:26:10.151 2017] [40636.748251] [<7f44ed74>] (hdmi_release+0x316c/0x781c [stm_cdi_dvb]) from [<7f4539a0>] (hdmi_ioctl+0x57c/0x2d40 [stm_cdi_dvb]) [Fri May 05 05:26:10.152 2017] [40636.759631] [<7f4539a0>] (hdmi_ioctl+0x57c/0x2d40 [stm_cdi_dvb]) from [<800fd4dc>] (vfs_ioctl+0x28/0x3c) [Fri May 05 05:26:10.152 2017] [40636.769137] [<800fd4dc>] (vfs_ioctl+0x28/0x3c) from [<800fdf48>] (do_vfs_ioctl+0x4b0/0x560) [Fri May 05 05:26:10.152 2017] [40636.777484] [<800fdf48>] (do_vfs_ioctl+0x4b0/0x560) from [<800fe02c>] (SyS_ioctl+0x34/0x60) [Fri May 05 05:26:10.152 2017] [40636.785836] [<800fe02c>] (SyS_ioctl+0x34/0x60) from [<8000dbc0>] (ret_fast_syscall+0x0/0x30) -- You are receiving this mail because: You are watching the assignee of the bug.
