Re: [PATCH 1/2] mmc: bcm2835: reset host on timeout

From: Michal SuchÃnek
Date: Sun Mar 04 2018 - 11:05:02 EST


Hello,

On Sat, 3 Mar 2018 14:58:45 +0100 (CET)
Stefan Wahren <stefan.wahren@xxxxxxxx> wrote:

> Hi Michal,

> yesterday i finished my stress tests with Raspberry Pi 3.
>
> Scenario:
> - copy Tumbleweed on SD card
> (openSUSE-Tumbleweed-ARM-JeOS-raspberrypi3.aarch64-2018.02.02-Build1.2.raw,
> Linux 4.14.15)
> - setup locales with yast
> - run zypper update
> - reboot
> - install and remove java 1.8 in a loop for at least 1 hour

How many cycles does that perform?

>
> Results of the different SD cards:
> Toshiba uSDHC Class 10 UHS-1 32 GB: PASS
> BASETech uSDHC Class 10 16 GB: PASS
> Samsung uSDHC EVO+ UHS-1 16 GB: PASS
> Samsung uSDHC Class 6 32 GB: PASS
> SanDisk Edge Class 4 16 GB: PASS
> Kingston uSDHC Class 10 UHS-1 32 GB: PASS
> QUMOX uSDHC Class 10 UHS-1 16 GB: FAIL (zypper segfaulted
> permantently)

It may very well segfault because the card disconnected due to the
timeout and it is missing some pages of its code. It did for me as well
without the workaround.

> Transcend uSDHC Class 10 UHS-1 32 GB: PASS
>
> I was never able to reproduce this timeout. So i still need the
> feedback about the 4.15 and i a reliable test scenario.

You may very well never get any. AFAICT this is some kind of heisenbug
in the hardware.

Thanks

Michal