3.16.69-rc1 review patch. If anyone has any objections, please let me know.
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From: Jason Yan yanaijie@huawei.com
commit bcf3b67d16a4c8ffae0aa79de5853435e683945c upstream.
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: Jason Yan yanaijie@huawei.com Acked-by: Sumit Saxena sumit.saxena@broadcom.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/scsi/megaraid/megaraid_sas_base.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/scsi/megaraid/megaraid_sas_base.c +++ b/drivers/scsi/megaraid/megaraid_sas_base.c @@ -3489,6 +3489,7 @@ int megasas_alloc_cmds(struct megasas_in if (megasas_create_frame_pool(instance)) { printk(KERN_DEBUG "megasas: Error creating frame DMA pool\n"); megasas_free_cmds(instance); + return -ENOMEM; }
return 0;