Target de-configuration panics at high CPU load. TPGT and WWPN can be removed on separate threads. TPGT removal requests a reset HBA on a separate thread and waits for reset complete (qlt_stop_phase1). Due to high CPU load that HBA reset can be delayed for some time. WWPN removal does qlt_stop_phase2 where it is thinked that phase1 has been already finished and zeroed tgt.tgt_ops that is used by incoming traffic and causes several panics: NIP qlt_reset+0x7c/0x220 [qla2xxx] LR qlt_reset+0x68/0x220 [qla2xxx] Call Trace: 0xc000003ffff63a78 (unreliable) qlt_handle_imm_notify+0x800/0x10c0 [qla2xxx] qlt_24xx_atio_pkt+0x208/0x590 [qla2xxx] qlt_24xx_process_atio_queue+0x33c/0x7a0 [qla2xxx] qla83xx_msix_atio_q+0x54/0x90 [qla2xxx] or NIP qlt_24xx_handle_abts+0xd0/0x2a0 [qla2xxx] LR qlt_24xx_handle_abts+0xb4/0x2a0 [qla2xxx] Call Trace: qlt_24xx_handle_abts+0x90/0x2a0 [qla2xxx] (unreliable) qlt_24xx_process_atio_queue+0x500/0x7a0 [qla2xxx] qla83xx_msix_atio_q+0x54/0x90 [qla2xxx] or NIP qlt_create_sess+0x90/0x4e0 [qla2xxx] LR qla24xx_do_nack_work+0xa8/0x180 [qla2xxx] Call Trace: 0xc0000000348fba30 (unreliable) qla24xx_do_nack_work+0xa8/0x180 [qla2xxx] qla2x00_do_work+0x674/0xbf0 [qla2xxx] qla2x00_iocb_work_fn The patch fixes the issue by serializing qlt_stop_phase1 and qlt_stop_phase2 functions to make WWPN removal waits for phase1 completion. Reviewed-by: Roman Bolshakov <r.bolshakov@xxxxxxxxx> Signed-off-by: Dmitry Bogdanov <d.bogdanov@xxxxxxxxx> --- Patch is for scsi-fixes tree. The issue is very old, but the patch is applicable for 4.20+ versions. drivers/scsi/qla2xxx/qla_target.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/scsi/qla2xxx/qla_target.c b/drivers/scsi/qla2xxx/qla_target.c index 480e7d2dcf3e..745d6d98c02e 100644 --- a/drivers/scsi/qla2xxx/qla_target.c +++ b/drivers/scsi/qla2xxx/qla_target.c @@ -1558,10 +1558,12 @@ void qlt_stop_phase2(struct qla_tgt *tgt) return; } + mutex_lock(&tgt->ha->optrom_mutex); mutex_lock(&vha->vha_tgt.tgt_mutex); tgt->tgt_stop = 0; tgt->tgt_stopped = 1; mutex_unlock(&vha->vha_tgt.tgt_mutex); + mutex_unlock(&tgt->ha->optrom_mutex); ql_dbg(ql_dbg_tgt_mgt, vha, 0xf00c, "Stop of tgt %p finished\n", tgt); -- 2.25.1