[PATCH 5.15 066/667] scsi: lpfc: Move cfg_log_verbose check before calling lpfc_dmp_dbg()

From: Greg Kroah-Hartman
Date: Tue Jun 07 2022 - 14:27:23 EST


From: James Smart <jsmart2021@xxxxxxxxx>

[ 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@xxxxxxxxx
Co-developed-by: Justin Tee <justin.tee@xxxxxxxxxxxx>
Signed-off-by: Justin Tee <justin.tee@xxxxxxxxxxxx>
Signed-off-by: James Smart <jsmart2021@xxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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)
--
2.35.1