gptboot broken when compiled with clang 6 and WITHOUT_LOADER_GELI -- clang 5 is OK

[Andre Albsmeier]

On Thu, 26-Apr-2018 at 12:06:21 +0200, Dimitry Andric wrote:
> On 26 Apr 2018, at 06:17, Dewayne Geraghty <dewayne.geraghty at heuristicsystems.com.au> wrote:
> > 
> > Andre, You're not alone.  I think there's a problem with clang6 on i386
> > FreeBSD 11.1X, refer:
> > https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=227552
> > https://forums.freebsd.org/threads/uptime-w-i386-breakage.65584/
> > and perhaps also on amd64, search for
> > https://bugs.freebsd.org/bugzilla/buglist.cgi?quicksearch=clang&list_id=226390.
> > 
> > Without time to investigate I've reverted userland
> > FreeBSD 11.2-PRERELEASE  r332843M    amd64 1101515 1101509
> > FreeBSD 11.2-PRERELEASE  r332843M    i386 1101515 1101509
> 
> As noted in another post, I cannot reproduce the problems with gptboot,
> but with FreeBSD-11.2-PRERELEASE-i386-20180420-r332802, I do indeed see
> w and uptime crashing in libxo:

Scary, seems to be OK here:

buildbox:~>cat /usr/src/.svn_revision 
333056
buildbox:~>uname -K -m
i386 1101515
buildbox:~>w
19:51  up  4:41, 1 user, load averages: 0,25 0,26 0,21
USER       TTY      FROM                                      LOGIN@  IDLE WHAT
andre      pts/0    bali                                     19:42       - w
buildbox:~>uptime
19:51  up  4:41, 1 user, load averages: 0,25 0,26 0,21
buildbox:~>ll /lib/libxo.so.0 
-r--r--r--  1 root  wheel  97596 27 Apr 15:07 /lib/libxo.so.0
buildbox:~>

	-Andre

> 
> (gdb) bt
> #0  ifree (tsd=0x28000000) at arena.h:799
> #1  0x2814b506 in __free (ptr=0x280601ef) at tsd.h:716
> #2  0x2808bb07 in xo_do_emit_fields () at /usr/src/contrib/libxo/libxo/libxo.c:6419
> #3  0x28089a1c in xo_do_emit (xop=<value optimized out>, flags=<value optimized out>, fmt=0x804ad4d "{:time-of-day/%s} ") at /usr/src/contrib/libxo/libxo/libxo.c:6470
> #4  0x28089b61 in xo_emit (fmt=0x804ad4d "{:time-of-day/%s} ") at /usr/src/contrib/libxo/libxo/libxo.c:6541
> #5  0x08049f50 in main (argc=<value optimized out>, argv=<value optimized out>) at /usr/src/usr.bin/w/w.c:475
> #6  0x080494cd in _start1 ()
> #7  0x08049448 in _start ()
> #8  0x00000000 in ?? ()
> 
> Not sure if this has anything to do with clang though, it looks more
> like a double free to me, at first glance.  I'll do some debugging.
> 
> -Dimitry
> 



-- 
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