2015-09-16 7:20 GMT+08:00 Peter Hurley [off-list ref]:

On Wed, Sep 9, 2015 at 3:54 PM, Greg Kroah-Hartman [off-list ref] wrote:

quoted

On Sat, Sep 05, 2015 at 10:42:03PM +0800, Jun Nie wrote:

quoted

2015-09-04 0:08 GMT+08:00 Marc Zyngier [off-list ref]:

quoted

On 03/09/15 16:52, Greg Kroah-Hartman wrote:

quoted

On Thu, Sep 03, 2015 at 11:23:15AM +0100, Marc Zyngier wrote:

quoted

On 11/08/15 02:48, Jun Nie wrote:

quoted

2015-08-11 7:23 GMT+08:00 Leif Lindholm [off-list ref]:

quoted

Hi all,

The kernelci.org bot picked up a complete boot failure (no output
past
UEFI stub) with next-20150806 and Tyler bisected it down to
somewhere
in
8cd90e5 uart: pl011: Add support to ZTE ZX296702 uart
09dcc7d uart: pl011: Improve LCRH register access decision
2c096a9 uart: pl011: Introduce register look up table
7b753f3 uart: pl011: Introduce register accessor

The issue only appears with earlycon on command line, for pl011
consoles.

Some investigation shows that the cause lies with
commit 7b753f318d14 ("uart: pl011: Introduce register accessor")
and
commit 2c096a9eedc6 ("uart: pl011: Introduce register look up
table")

Specifically, the changes to pl011_putc() are incorrect:
The new pl011_ accessors take a (struct uart_amba_port *) input,
but
pl011_putc() directly uses the incoming (struct uart_port *) for
this.

Apart from ending up with an unintended/incorrect UART base
address,
the introduction of the lookup table for register offsets also
means
the accessors try to dereference (struct uart_amba_port
*)->reg_lut.

The below is a hack that shows/resolves the issue, but some
refactoring of the original patches might be in order.

/
    Leif

Leif,

Sorry for the inconvenience. I do not have idea of early console
till
now and I always have debug console for early panic debug. Learned
more from this issue.

Suppose Peter's patch will resolve your issue.

[+ Greg KH]

So -next has now been broken for a while on a number of ARM
platforms
because of this (they simply cannot boot), and no progress has been
made
towards resolving this problem.

Can we please drop this series (at least commits 7b753f3 and
following)
from -next until is has been reworked and reviewed?

I don't have any patches in my -next tree, everything is in Linus's
tree
now.  So if I've missed something, or need to revert something,
please
let me know specifcally what to do.

Gahhh... Given that there is no obvious fix, that the discussion has
stalled and that the author of the series is apparently away, the
following patches should be reverted:

Marc,

There had a patch from Peter that revert early console part, which I
thought will be merged to mainline. It's my fault for not fix the bug
on time. Also sorry for late response to you as I took three days
leave.

Could you help test attached patch? Thank you in advance!


Greg,

Would you please hold the merging of revert patches for one or two
days so that the fix can be verified? Thank you!

Given that this took way more than a few days, Linus now has the reverts
in his tree.  Please feel free to resend the series, in a form that does
not break people's machines, for inclusion in 4.4-rc1.

Jun,

I suggest you keep the series largely as is, while leaving the earlycon
support unmodified.

Be sure to address the series to all in this email so they have adequate
opportunity to test your driver changes, prior to inclusion in mainline.

Regards,
Peter Hurley

Will do in one month due to occupied in internal tasks. Thanks for
your suggestion!

Best Regards,
Jun