On 3/15/21 9:54 PM, Bart Van Assche wrote: > This patch fixes the following kernel warning: > > BUG: using smp_processor_id() in preemptible [00000000] code: scsi_eh_0/152 > caller is debug_smp_processor_id+0x17/0x20 > CPU: 1 PID: 152 Comm: scsi_eh_0 Tainted: G W 5.12.0-rc1-dbg+ #6 > Call Trace: > show_stack+0x52/0x58 > dump_stack+0xaf/0xf3 > check_preemption_disabled+0xce/0xd0 > debug_smp_processor_id+0x17/0x20 > scsi_device_unbusy+0x13a/0x1c0 [scsi_mod] > scsi_finish_command+0x4d/0x290 [scsi_mod] > scsi_eh_flush_done_q+0x1e7/0x280 [scsi_mod] > ata_scsi_port_error_handler+0x592/0x750 [libata] > ata_scsi_error+0x1a0/0x1f0 [libata] > scsi_error_handler+0x19e/0x330 [scsi_mod] > kthread+0x222/0x250 > ret_from_fork+0x1f/0x30 It'd be nice to have a bit of a description in here on what is being fixed, eg that we're preemptible and cannot safely use this_cpu_ptr(), and why that it's OK to use raw_cpu_ptr() instead for this particular application. -- Jens Axboe
