Subject: Re: linux-next: build failure after merge of the tty tree

From: Sebastian Andrzej Siewior <[email-masked]>
Date: Tue, 30 Sep 2014 09:52:39 +0200

* Stephen Rothwell | 2014-09-30 17:39:00 [+1000]:

>Hi Greg,
Hi Stephen,

>After merging the tty tree, today's linux-next build (powerpc
>ppc64_defconfig) failed like this:
>
>
>drivers/built-in.o: In function `.serial8250_stop_tx':
>8250_core.c:(.text+0xda1f4): undefined reference to `.__xchg_called_with_bad_pointer'
>drivers/built-in.o: In function `.serial8250_tx_chars':
>(.text+0xda42c): undefined reference to `.__xchg_called_with_bad_pointer'
>drivers/built-in.o: In function `.serial8250_start_tx':
>8250_core.c:(.text+0xda630): undefined reference to `.__xchg_called_with_bad_pointer'
>
>Caused by commit d74d5d1b7288 ("tty: serial: 8250_core: add run time
>pm").  xchg is called with &p->rpm_tx_active and that is an unsigned
>char.  PowerPC (at least) only allows xchg with objects 4 (or 8 on 64
>bit) bytes long.
>
>I have used the version of the tty tree from next-20140926 for today.

this should have been fixed by commit baeb7ef34952f ("tty: serial: 8250:
use 32bit variable for rpm_tx_active") in Greg's tty-next tree. Isn't
this the case or did you fetch the tty tree before Greg pushed it?

Sebastian