From: James Smart jsmart2021@gmail.com
[ Upstream commit e294647b1aed4247fe52851f3a3b2b19ae906228 ]
In an attempt to log message 0126 with LOG_TRACE_EVENT, the following hard lockup call trace hangs the system.
Call Trace: _raw_spin_lock_irqsave+0x32/0x40 lpfc_dmp_dbg.part.32+0x28/0x220 [lpfc] lpfc_cmpl_els_fdisc+0x145/0x460 [lpfc] lpfc_sli_cancel_jobs+0x92/0xd0 [lpfc] lpfc_els_flush_cmd+0x43c/0x670 [lpfc] lpfc_els_flush_all_cmd+0x37/0x60 [lpfc] lpfc_sli4_async_event_proc+0x956/0x1720 [lpfc] lpfc_do_work+0x1485/0x1d70 [lpfc] kthread+0x112/0x130 ret_from_fork+0x1f/0x40 Kernel panic - not syncing: Hard LOCKUP
The same CPU tries to claim the phba->port_list_lock twice.
Move the cfg_log_verbose checks as part of the lpfc_printf_vlog() and lpfc_printf_log() macros before calling lpfc_dmp_dbg(). There is no need to take the phba->port_list_lock within lpfc_dmp_dbg().
Link: https://lore.kernel.org/r/20220412222008.126521-3-jsmart2021@gmail.com Co-developed-by: Justin Tee justin.tee@broadcom.com Signed-off-by: Justin Tee justin.tee@broadcom.com Signed-off-by: James Smart jsmart2021@gmail.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/lpfc/lpfc_init.c | 29 +---------------------------- drivers/scsi/lpfc/lpfc_logmsg.h | 6 +++--- 2 files changed, 4 insertions(+), 31 deletions(-)
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c index 16246526e4c1..ce103c1f8062 100644 --- a/drivers/scsi/lpfc/lpfc_init.c +++ b/drivers/scsi/lpfc/lpfc_init.c @@ -15564,34 +15564,7 @@ void lpfc_dmp_dbg(struct lpfc_hba *phba) unsigned int temp_idx; int i; int j = 0; - unsigned long rem_nsec, iflags; - bool log_verbose = false; - struct lpfc_vport *port_iterator; - - /* Don't dump messages if we explicitly set log_verbose for the - * physical port or any vport. - */ - if (phba->cfg_log_verbose) - return; - - spin_lock_irqsave(&phba->port_list_lock, iflags); - list_for_each_entry(port_iterator, &phba->port_list, listentry) { - if (port_iterator->load_flag & FC_UNLOADING) - continue; - if (scsi_host_get(lpfc_shost_from_vport(port_iterator))) { - if (port_iterator->cfg_log_verbose) - log_verbose = true; - - scsi_host_put(lpfc_shost_from_vport(port_iterator)); - - if (log_verbose) { - spin_unlock_irqrestore(&phba->port_list_lock, - iflags); - return; - } - } - } - spin_unlock_irqrestore(&phba->port_list_lock, iflags); + unsigned long rem_nsec;
if (atomic_cmpxchg(&phba->dbg_log_dmping, 0, 1) != 0) return; diff --git a/drivers/scsi/lpfc/lpfc_logmsg.h b/drivers/scsi/lpfc/lpfc_logmsg.h index 7d480c798794..a5aafe230c74 100644 --- a/drivers/scsi/lpfc/lpfc_logmsg.h +++ b/drivers/scsi/lpfc/lpfc_logmsg.h @@ -73,7 +73,7 @@ do { \ #define lpfc_printf_vlog(vport, level, mask, fmt, arg...) \ do { \ { if (((mask) & (vport)->cfg_log_verbose) || (level[1] <= '3')) { \ - if ((mask) & LOG_TRACE_EVENT) \ + if ((mask) & LOG_TRACE_EVENT && !(vport)->cfg_log_verbose) \ lpfc_dmp_dbg((vport)->phba); \ dev_printk(level, &((vport)->phba->pcidev)->dev, "%d:(%d):" \ fmt, (vport)->phba->brd_no, vport->vpi, ##arg); \ @@ -89,11 +89,11 @@ do { \ (phba)->pport->cfg_log_verbose : \ (phba)->cfg_log_verbose; \ if (((mask) & log_verbose) || (level[1] <= '3')) { \ - if ((mask) & LOG_TRACE_EVENT) \ + if ((mask) & LOG_TRACE_EVENT && !log_verbose) \ lpfc_dmp_dbg(phba); \ dev_printk(level, &((phba)->pcidev)->dev, "%d:" \ fmt, phba->brd_no, ##arg); \ - } else if (!(phba)->cfg_log_verbose)\ + } else if (!log_verbose)\ lpfc_dbg_print(phba, "%d:" fmt, phba->brd_no, ##arg); \ } \ } while (0)