Re: [PATCH v2] ath10k: add fw coredump for sdio when firmware assert

[Wen Gong <wgong@codeaurora.org>]

On 2019-09-23 19:37, Kalle Valo wrote:
> Wen Gong <wgong@codeaurora.org> writes:
> 
>> On 2019-09-21 19:38, Kalle Valo wrote:
>>> 
>>> What's wrong with ath10k_sdio_hif_diag_read()? AFAICS this whole
>>> function duplicates just what it does.
>> 
>> ath10k_sdio_hif_diag_read's buffer size is limit,
>> and the dump memory/register's buffer size is larger than the diag
>> window's limit,
>> if use it directly will trigger crash like this for every time.
> 
> You shouldn't blindly add extra code to ath10k workaround issues. And 
> if
> you really need to use a workaround, then it needs to properly 
> explained
> in the commit and as well as commented in the code. But before that the
> issue needs to be thoroughly investigated and understood where the
> problem is coming from. Because it might be even completely unrelated 
> to
> ath10k.

> 
>> [  149.947624] ath10k_sdio mmc1:0001:1: ath10k_sdio_hif_diag_read
>> buf_len :4
>> [  149.954741] ath10k_sdio mmc1:0001:1: ath10k_sdio_hif_diag_read
>> buf_len :240
>> [  151.005143] Unable to handle kernel paging request at virtual

>> [  151.114537] Process swapper/0 (pid: 0, stack limit =
>> 0x00000000e30dc665)
、
> 
> Did you investigate this? Is the buffer you reading to DMA accessible?
> What about the alignment? Is there a certain length which is the limit
> for crashes? And so on...
the limit is 4 byte.
for 5 bytes, it will crash.