[PATCH 5.17 081/772] scsi: lpfc: Fix call trace observed during I/O with CMF enabled

From: Greg Kroah-Hartman
Date: Tue Jun 07 2022 - 16:39:08 EST


From: James Smart <jsmart2021@xxxxxxxxx>

[ Upstream commit d6d45f67a11136cb88a70a29ab22ea6db8ae6bd5 ]

The following was seen with CMF enabled:

BUG: using smp_processor_id() in preemptible
code: systemd-udevd/31711
kernel: caller is lpfc_update_cmf_cmd+0x214/0x420 [lpfc]
kernel: CPU: 12 PID: 31711 Comm: systemd-udevd
kernel: Call Trace:
kernel: <TASK>
kernel: dump_stack_lvl+0x44/0x57
kernel: check_preemption_disabled+0xbf/0xe0
kernel: lpfc_update_cmf_cmd+0x214/0x420 [lpfc]
kernel: lpfc_nvme_fcp_io_submit+0x23b4/0x4df0 [lpfc]

this_cpu_ptr() calls smp_processor_id() in a preemptible context.

Fix by using per_cpu_ptr() with raw_smp_processor_id() instead.

Link: https://lore.kernel.org/r/20220412222008.126521-16-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_scsi.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_scsi.c b/drivers/scsi/lpfc/lpfc_scsi.c
index 6cc94fae01b8..d9a8e3a59d94 100644
--- a/drivers/scsi/lpfc/lpfc_scsi.c
+++ b/drivers/scsi/lpfc/lpfc_scsi.c
@@ -3936,7 +3936,7 @@ lpfc_update_cmf_cmpl(struct lpfc_hba *phba,
else
time = div_u64(time + 500, 1000); /* round it */

- cgs = this_cpu_ptr(phba->cmf_stat);
+ cgs = per_cpu_ptr(phba->cmf_stat, raw_smp_processor_id());
atomic64_add(size, &cgs->rcv_bytes);
atomic64_add(time, &cgs->rx_latency);
atomic_inc(&cgs->rx_io_cnt);
@@ -3980,7 +3980,7 @@ lpfc_update_cmf_cmd(struct lpfc_hba *phba, uint32_t size)
atomic_set(&phba->rx_max_read_cnt, size);
}

- cgs = this_cpu_ptr(phba->cmf_stat);
+ cgs = per_cpu_ptr(phba->cmf_stat, raw_smp_processor_id());
atomic64_add(size, &cgs->total_bytes);
return 0;
}
--
2.35.1