Re: [PATCH 2/2] libata: Fix NULL pointer of scsi_host in ata_port

From: Mike Qiu
Date: Tue Jul 22 2014 - 22:37:51 EST


On 07/22/2014 10:51 PM, Mike Qiu wrote:
In ata_sas_port_alloc(), it haven't initialized scsi_host field in
ata_port, although scsi_host is in parameters list and unused in this
function.

With commit 1871ee134b73 ("libata: support the ata host which implements a queue depth less than 32")
ata_qc_new() try to use scsi_host, while it
is a NULL pointer for ipr IOA and error message shows below:
...

While scsi_host is unused in ata_sas_port_alloc(), better to set it
in ata_sas_port_alloc() instead of in driver.

Signed-off-by: Mike Qiu <qiudayu@xxxxxxxxxxxxxxxxxx>
---
drivers/ata/libata-scsi.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 0586f66..a472b6f 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -4070,6 +4070,7 @@ struct ata_port *ata_sas_port_alloc(struct ata_host *host,
ap->flags |= port_info->flags;
ap->ops = port_info->port_ops;
ap->cbl = ATA_CBL_SATA;
+ ap->scsi_host = shost;

What about my patch itself, ata_sas_port_alloc() has "shot" in parameters list, but unused.

Maybe better to set ap->scsi_host here, it is very convenient, and drivers, like ipr, may forget to set this field, otherwise "shot" need to be removed from parameters list I think.

Thanks,
Mike
return ap;
}

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