[PATCH 5.10 075/157] scsi: pm80xx: Make mpi_build_cmd locking consistent

Greg Kroah-Hartman
2021-03-22T12:50:05Z

From: peter chang <dpf@google.com>

[ Upstream commit 7640e1eb8c5de33dafa6c68fd4389214ff9ec1f9 ]

Driver submits all internal requests (like abort_task, event acknowledgment
etc.) through inbound queue 0. While submitting those, driver does not
acquire any lock and this may lead to a race when there is an I/O request
coming in on CPU0 and submitted through inbound queue 0. To avoid this,
lock acquisition has been moved to pm8001_mpi_build_cmd(). All command
submission will go through this path.

Link: https://lore.kernel.org/r/20201102165528.26510-2-Viswas.G@microchip.com.com
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: peter chang <dpf@google.com>
Signed-off-by: Viswas G <Viswas.G@microchip.com>
Signed-off-by: Ruksar Devadi <Ruksar.devadi@microchip.com>
Signed-off-by: Radha Ramachandran <radha@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/scsi/pm8001/pm8001_hwi.c | 21 +++++++++++++++------
drivers/scsi/pm8001/pm80xx_hwi.c | 8 --------
2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/pm8001/pm8001_hwi.c b/drivers/scsi/pm8001/pm8001_hwi.c
index 2b7b2954ec31..597d7a096a97 100644
--- a/drivers/scsi/pm8001/pm8001_hwi.c
+++ b/drivers/scsi/pm8001/pm8001_hwi.c
@@ -1356,12 +1356,19 @@ int pm8001_mpi_build_cmd(struct pm8001_hba_info *pm8001_ha,
{
u32 Header = 0, hpriority = 0, bc = 1, category = 0x02;
void *pMessage;
-
- if (pm8001_mpi_msg_free_get(circularQ, pm8001_ha->iomb_size,
- &pMessage) < 0) {
+ unsigned long flags;
+ int q_index = circularQ - pm8001_ha->inbnd_q_tbl;
+ int rv = -1;
+
+ WARN_ON(q_index >= PM8001_MAX_INB_NUM);
+ spin_lock_irqsave(&circularQ->iq_lock, flags);
+ rv = pm8001_mpi_msg_free_get(circularQ, pm8001_ha->iomb_size,
+ &pMessage);
+ if (rv < 0) {
PM8001_IO_DBG(pm8001_ha,
- pm8001_printk("No free mpi buffer\n"));
- return -ENOMEM;
+ pm8001_printk("No free mpi buffer\n"));
+ rv = -ENOMEM;
+ goto done;
}

if (nb > (pm8001_ha->iomb_size - sizeof(struct mpi_msg_hdr)))
@@ -1384,7 +1391,9 @@ int pm8001_mpi_build_cmd(struct pm8001_hba_info *pm8001_ha,
pm8001_printk("INB Q %x OPCODE:%x , UPDATED PI=%d CI=%d\n",
responseQueue, opCode, circularQ->producer_idx,
circularQ->consumer_index));
- return 0;
+done:
+ spin_unlock_irqrestore(&circularQ->iq_lock, flags);
+ return rv;
}

u32 pm8001_mpi_msg_free_set(struct pm8001_hba_info *pm8001_ha, void *pMsg,
diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c
index 155382ce8469..c9a89e980e1c 100644
--- a/drivers/scsi/pm8001/pm80xx_hwi.c
+++ b/drivers/scsi/pm8001/pm80xx_hwi.c
@@ -4281,7 +4281,6 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha,
char *preq_dma_addr = NULL;
__le64 tmp_addr;
u32 i, length;
- unsigned long flags;

memset(&smp_cmd, 0, sizeof(smp_cmd));
/*
@@ -4377,10 +4376,8 @@ static int pm80xx_chip_smp_req(struct pm8001_hba_info *pm8001_ha,

build_smp_cmd(pm8001_dev->device_id, smp_cmd.tag,
&smp_cmd, pm8001_ha->smp_exp_mode, length);
- spin_lock_irqsave(&circularQ->iq_lock, flags);
rc = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc, &smp_cmd,
sizeof(smp_cmd), 0);
- spin_unlock_irqrestore(&circularQ->iq_lock, flags);
if (rc)
goto err_out_2;
return 0;
@@ -4444,7 +4441,6 @@ static int pm80xx_chip_ssp_io_req(struct pm8001_hba_info *pm8001_ha,
u64 phys_addr, start_addr, end_addr;
u32 end_addr_high, end_addr_low;
struct inbound_queue_table *circularQ;
- unsigned long flags;
u32 q_index, cpu_id;
u32 opc = OPC_INB_SSPINIIOSTART;
memset(&ssp_cmd, 0, sizeof(ssp_cmd));
@@ -4582,10 +4578,8 @@ static int pm80xx_chip_ssp_io_req(struct pm8001_hba_info *pm8001_ha,
ssp_cmd.esgl = 0;
}
}
- spin_lock_irqsave(&circularQ->iq_lock, flags);
ret = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc,
&ssp_cmd, sizeof(ssp_cmd), q_index);
- spin_unlock_irqrestore(&circularQ->iq_lock, flags);
return ret;
}

@@ -4819,10 +4813,8 @@ static int pm80xx_chip_sata_req(struct pm8001_hba_info *pm8001_ha,
}
}
}
- spin_lock_irqsave(&circularQ->iq_lock, flags);
ret = pm8001_mpi_build_cmd(pm8001_ha, circularQ, opc,
&sata_cmd, sizeof(sata_cmd), q_index);
- spin_unlock_irqrestore(&circularQ->iq_lock, flags);
return ret;
}

--
2.30.1