Re: [PATCH] PCI: iproc: fix kernel crash if dev->of_node not defined

[Ray Jui]

Hi Florian,

On 1/12/2017 4:22 PM, Florian Fainelli wrote:
> On 01/12/2017 04:20 PM, Abylay Ospan wrote:
>> pcie->dev->of_node not always defined (NULL) and can cause crash:
>>
>> [   19.053195] Unable to handle kernel NULL pointer dereference at
>> virtual address 00000020
>> [<c0b0370c>] (of_n_addr_cells) from [<c06599c4>]
>> (iproc_pcie_setup+0x30c/0xce0)
>>
>> this patch adds sanity check to prevent crash.
> 
> Humm, how can it not be defined based on your earlier comment that you
> are using this on NSP which is Device Tree exclusively? I would agree if
> this was seen on e.g: MIPS/BCMA (47xx).

I thought Abylay mentioned:

"Tested on Broadcom NorthStar machine ('Edgecore ECW7220-L') with two
PCIe wifi
adapters (b43 BCM4331 and ath10k QCA988X)."

That is a NorthStar device which is BCMA based?

> 
>>
>> Signed-off-by: Abylay Ospan <aospan@xxxxxxxx>
>> ---
>>  drivers/pci/host/pcie-iproc.c | 3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/pci/host/pcie-iproc.c b/drivers/pci/host/pcie-iproc.c
>> index 3ebc025..f2836a9 100644
>> --- a/drivers/pci/host/pcie-iproc.c
>> +++ b/drivers/pci/host/pcie-iproc.c
>> @@ -952,6 +952,9 @@ static int pci_dma_range_parser_init(struct of_pci_range_parser *parser,
>>  	const int na = 3, ns = 2;
>>  	int rlen;
>>  
>> +	if (!node)
>> +		return -ENOENT;
>> +
>>  	parser->node = node;
>>  	parser->pna = of_n_addr_cells(node);
>>  	parser->np = parser->pna + na + ns;
>>
> 
>