[PATCH AUTOSEL for 4.4 085/101] scsi: hpsa: destroy sas transport properties before scsi_host

From: alexander . levin
Date: Thu Dec 07 2017 - 11:32:52 EST


From: Martin Wilck <mwilck@xxxxxxx>

[ Upstream commit dfb2e6f46b3074eb85203d8f0888b71ec1c2e37a ]

This patch cleans up a lot of warnings when unloading the driver.

A current example of the stack trace starts with:
[ 142.570715] sysfs group 'power' not found for kobject 'port-5:0'
There can be hundreds of these messages during a driver unload.

I am resubmitting this patch on behalf of Martin Wilck with his
permission.

His original patch can be found here:
https://www.spinics.net/lists/linux-scsi/msg102085.html

This patch did not help until Hannes's
commit 9441284fbc39 ("scsi-fixup-kernel-warning-during-rmmod")
was applied to the kernel.

---------------------------
Original patch description:
---------------------------

Unloading the hpsa driver causes warnings

[ 1063.793652] WARNING: CPU: 1 PID: 4850 at ../fs/sysfs/group.c:237 device_del+0x54/0x240()
[ 1063.793659] sysfs group ffffffff81cf21a0 not found for kobject 'port-2:0'

with two different stacks:
1)
[ 1063.793774] [<ffffffff81448af4>] device_del+0x54/0x240
[ 1063.793780] [<ffffffff8145178a>] transport_remove_classdev+0x4a/0x60
[ 1063.793784] [<ffffffff81451216>] attribute_container_device_trigger+0xa6/0xb0
[ 1063.793802] [<ffffffffa0105d46>] sas_port_delete+0x126/0x160 [scsi_transport_sas]
[ 1063.793819] [<ffffffffa036ebcc>] hpsa_free_sas_port+0x3c/0x70 [hpsa]

2)
[ 1063.797103] [<ffffffff81448af4>] device_del+0x54/0x240
[ 1063.797118] [<ffffffffa0105d4e>] sas_port_delete+0x12e/0x160 [scsi_transport_sas]
[ 1063.797134] [<ffffffffa036ebcc>] hpsa_free_sas_port+0x3c/0x70 [hpsa]

This is caused by the fact that host device hostX is deleted before the
SAS transport devices hostX/port-a:b.

This patch fixes this by reverting the order of device deletions.

Tested-by: Don Brace <don.brace@xxxxxxxxxxxxx>
Reviewed-by: Don Brace <don.brace@xxxxxxxxxxxxx>
Signed-off-by: Martin Wilck <mwilck@xxxxxxx>
Signed-off-by: Don Brace <don.brace@xxxxxxxxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
drivers/scsi/hpsa.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
index b37e85126f63..0c87f341fed4 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -8808,6 +8808,8 @@ static void hpsa_remove_one(struct pci_dev *pdev)
destroy_workqueue(h->rescan_ctlr_wq);
destroy_workqueue(h->resubmit_wq);

+ hpsa_delete_sas_host(h);
+
/*
* Call before disabling interrupts.
* scsi_remove_host can trigger I/O operations especially
@@ -8842,8 +8844,6 @@ static void hpsa_remove_one(struct pci_dev *pdev)
h->lockup_detected = NULL; /* init_one 2 */
/* (void) pci_disable_pcie_error_reporting(pdev); */ /* init_one 1 */

- hpsa_delete_sas_host(h);
-
kfree(h); /* init_one 1 */
}

--
2.11.0