[PATCH 3/3] megaraid_sas: return -ENOMEM when create DMA pool for cmd frames failed

From: Weidong Wang
Date: Tue Oct 27 2015 - 04:27:49 EST


when create DMA pool for cmd frames failed, we should return -ENOMEM,
instead of 0.
In some case in:

megasas_init_adapter_fusion()

-->megasas_alloc_cmds()
-->megasas_create_frame_pool
create DMA pool failed,
--> megasas_free_cmds() [1]

-->megasas_alloc_cmds_fusion()
failed, then goto fail_alloc_cmds.
-->megasas_free_cmds() [2]

we will call megasas_free_cmds twice, [1] will kfree cmd_list,
[2] will use cmd_list.it will cause a problem:

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = ffffffc000f70000
[00000000] *pgd=0000001fbf893003, *pud=0000001fbf893003, *pmd=0000001fbf894003, *pte=006000006d000707
Internal error: Oops: 96000005 [#1] SMP
Modules linked in:
CPU: 18 PID: 1 Comm: swapper/0 Not tainted
task: ffffffdfb9290000 ti: ffffffdfb923c000 task.ti: ffffffdfb923c000
PC is at megasas_free_cmds+0x30/0x70
LR is at megasas_free_cmds+0x24/0x70

...

Call trace:
[<ffffffc0005b779c>] megasas_free_cmds+0x30/0x70
[<ffffffc0005bca74>] megasas_init_adapter_fusion+0x2f4/0x4d8
[<ffffffc0005b926c>] megasas_init_fw+0x2dc/0x760
[<ffffffc0005b9ab0>] megasas_probe_one+0x3c0/0xcd8
[<ffffffc0004a5abc>] local_pci_probe+0x4c/0xb4
[<ffffffc0004a5c40>] pci_device_probe+0x11c/0x14c
[<ffffffc00053a5e4>] driver_probe_device+0x1ec/0x430
[<ffffffc00053a92c>] __driver_attach+0xa8/0xb0
[<ffffffc000538178>] bus_for_each_dev+0x74/0xc8
[<ffffffc000539e88>] driver_attach+0x28/0x34
[<ffffffc000539a18>] bus_add_driver+0x16c/0x248
[<ffffffc00053b234>] driver_register+0x6c/0x138
[<ffffffc0004a5350>] __pci_register_driver+0x5c/0x6c
[<ffffffc000ce3868>] megasas_init+0xc0/0x1a8
[<ffffffc000082a58>] do_one_initcall+0xe8/0x1ec
[<ffffffc000ca7be8>] kernel_init_freeable+0x1c8/0x284
[<ffffffc0008d90b8>] kernel_init+0x1c/0xe4

Signed-off-by: Weidong Wang <wangweidong1@xxxxxxxxxx>
---
drivers/scsi/megaraid/megaraid_sas_base.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 2287aa1..8215218 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -3746,8 +3746,9 @@ int megasas_alloc_cmds(struct megasas_instance *instance)
* Create a frame pool and assign one frame to each cmd
*/
if (megasas_create_frame_pool(instance)) {
- dev_dbg(&instance->pdev->dev, "Error creating frame DMA pool\n");
+ dev_err(&instance->pdev->dev, "Error creating frame DMA pool\n");
megasas_free_cmds(instance);
+ return -ENOMEM;
}

return 0;
--
1.9.0


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/