Re: v6.16-rc5: ttys: auto login failed Login incorrect

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Wed, Jul 09, 2025 at 04:26:53PM +0530, Naresh Kamboju wrote:
> Approximately 20% of devices are experiencing intermittent boot failures
> with this kernel version. The issue appears to be related to auto login
> failures, where an incorrect password is being detected on the serial
> console during the login process.
> 
> This intermittent regression is noticed on stable-rc 6.15.5-rc2 and
> Linux mainline master v6.16-rc5. This regressions is only specific
> to the devices not on the qemu's.
> 
> Test environments:
>  - dragonboard-410c
>  - dragonboard-845c
>  - e850-96
>  - juno-r2
>  - rk3399-rock-pi-4b
>  - x86
> 
> Regression Analysis:
> - New regression? Yes
> - Reproducibility? 20% only
> 
> Test regression: 6.15.5-rc2 v6.16-rc5 auto login failed Login incorrect
> 
> Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
> 
> ## log in problem
> 
> runner-ns46nmmj-project-40964107-concurrent-0 login: #
> Password:
> Login incorrect
> runner-ns46nmmj-project-40964107-concurrent-0 login:
> 
> ## Investigation
> The following three patches were reverted and the system was re-tested.
> The previously reported issues are no longer observed after applying the
> reverts.
> 
> serial: imx: Restore original RXTL for console to fix data loss
>     commit f23c52aafb1675ab1d1f46914556d8e29cbbf7b3 upstream.
> 
> serial: core: restore of_node information in sysfs
>     commit d36f0e9a0002f04f4d6dd9be908d58fe5bd3a279 upstream.
> 
> tty: serial: uartlite: register uart driver in init
>     [ Upstream commit 6bd697b5fc39fd24e2aa418c7b7d14469f550a93 ]


As stated before, those are 3 totally independent changes.  Any chance
you can nail this down to just one of the above?

thanks,

greg k-h