Re: [PATCH 2/4] soc: qcom: stats: don't crash if DDR offset contains invalid data

[Konrad Dybcio <konrad.dybcio@linaro.org>]

On 12/14/23 01:59, Doug Anderson wrote:
> Hi,
> 
> On Mon, Dec 11, 2023 at 1:11 AM Konrad Dybcio <konrad.dybcio@linaro.org> wrote:
>>
>> On 9.12.2023 22:55, Dmitry Baryshkov wrote:
>>> The stats ram on sm8150 platform contains invalid data at the
>>> DDR_DYNAMIC_OFFSET. Most likely this is because the platform didn't
>>> support DDR sleep stats.
>> Interesting. Can you read back DDR_DYNAMIC_OFFSET on 8350/8280 and
>> see if 8150 has correct data in there?
>>
>>> However this platform uses generic
>>> "qcom,rpmh-stats" compatible, which implies presense of the DDR data.
>>> Add safety net to prevent old DTB files from crashing the
>>> qcom,rpmh-stats driver.
>> Yeah I'dve never thought there would be garbage in there..
>>
>> I'd advocate for simply not doing anything wrt sleep stats if DDR
>> stats are unavailable though. The QMP handle can stay, as there
>> may (I don't know) be more data available that we want to export
>> through this driver.
> 
> FWIW, I'm getting a crash on sc7180-trogdor like this too. In kgdb it
> says I'm on line:
> 
> key = readl(ddrd->base);
> 
> ...and
> 
> (gdb) print ddrd->base
> $1 = (void *) 0xffffffc0833a3149
> (gdb) print reg
> $2 = (void *) 0xffffffc0833a3000
> 
> ...so I guess my "stats_offset" must have been 0x149.
> 
> Can we get a fix landed or a revert? Thanks! :-)
Right, I guess we may want to revert it and I'll try to get more
info from Qualcomm folks..

Konrad