Package: emacs;
Reported by: David Matthew Mattli <dmm <at> mattli.us>
Date: Mon, 30 Nov 2015 16:32:03 UTC
Severity: important
Found in version 24.5
Fixed in version 25.1
Done: Glenn Morris <rgm <at> gnu.org>
Bug is archived. No further changes may be made.
Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):
From: David Matthew Mattli <dmm <at> mattli.us> To: bug-gnu-emacs <at> gnu.org Subject: 24.5; Build failure on sparc64, Bus Error in src/unexelf.c Date: Mon, 30 Nov 2015 09:13:59 -0600
On sparc64 gnu/linux, when emacs is configured with
'--with-x-toolkit=lucid' the build fails with a Bus Error in the source
file 'src/unexelf.c'. This would occur because the sparc architecture
requires pointers to be naturally aligned, so 8-byte access to by 8-byte
aligned, 4-byte access to be 4-byte aligned, etc. Attempting to access
memory at an improperly aligned address results in a SIGBUS.
This was discovered while investigating a broken build
in Debian. The Debian build log showing the error is here:
https://buildd.debian.org/status/fetch.php?pkg=emacs24&arch=sparc64&ver=24.5%2B1-5&stamp=1448688813
I've also reproduced the problem with the latest master branch of the
git tree from this morning. By running the failing command in gdb I
found that the SIGBUS is occuring in the file 'src/unexelf.c'. The crash
occurs when it's walking through the section headers, around line 411:
/* Walk through all section headers, copying data and updating. */
for (n = 1; n < old_file_h->e_shnum; n++)
{
caddr_t src;
ElfW (Shdr) *old_shdr = &OLD_SECTION_H (n);
ElfW (Shdr) *new_shdr = &NEW_SECTION_H (n);
if (new_shdr->sh_type == SHT_NOBITS // <======
&& new_shdr->sh_addr >= old_bss_addr
&& (new_shdr->sh_addr + new_shdr->sh_size
<= old_bss_addr + old_bss_size))
{
For the Debian build failure I was able to determine where the
misalignment was introduced but it seems this file has changed a
lot. You can see the Debian bug details here:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=806667
Looking at frame #0 in the backtrace below I can see that
'old_bss_offset', 'new_data2_size', and 'new_data2_offset' are
unaligned, those may be the problem if they are added to a pointer that
is later used in a memory access that requires alignment.
Let me know if I can do anything to help fix this issue. I can give
emacs developers access to a sparc64 dev box, etc.
$ git log -n 1
commit c77b816bc3d8fc242b95c04859803ffff5bb8210
Author: Stefan Monnier <monnier <at> iro.umontreal.ca>
Date: Mon Nov 30 08:02:55 2015 -0500
* lisp/calculator.el (calculator-define-key): Silence warning
...about unknown calculator-mode-map.
Here's the backtrace from gdb for the git tree build:
#0 unexec (new_name=0x1818d60 "/home/dmm/src/emacs/src/emacs",
old_name=0x1818d88 "/home/dmm/src/emacs/src/temacs") at unexelf.c:411
src = <optimized out>
new_file = 7
old_file = 6
new_file_size = 36500211
old_base = 0xffff800111c06000 "\177ELF\002\002\001"
new_base = 0xffff800112ca8000 "\177ELF\002\002\001"
old_file_h = 0xffff800111c06000
new_file_h = 0xffff800112ca8000
old_program_h = <optimized out>
new_program_h = <optimized out>
old_section_h = 0xffff800112ca5c20
new_section_h = 0xffff800114f76933
old_section_names = 0xffff800112ca5ab5 ""
new_section_names = <optimized out>
old_bss_seg = <optimized out>
new_bss_seg = 0xffff800112ca80e8
old_bss_addr = 7402221
new_bss_addr = 26468352
old_bss_size = <optimized out>
new_data2_size = 19066131
old_bss_offset = 5305069
new_data2_offset = 5305069
n = 1
old_bss_index = 25
stat_buf = {st_dev = 2066, __pad1 = 0, st_ino = 14040, st_mode = 33261, st_nlink = 1,
st_uid = 1000, st_gid = 1000, st_rdev = 0, __pad2 = 0, st_size = 17434080,
st_blksize = 4096, st_blocks = 34048, st_atim = {tv_sec = 1448893442,
tv_nsec = 941694653}, st_mtim = {tv_sec = 1448893442, tv_nsec = 481675054},
st_ctim = {tv_sec = 1448893442, tv_nsec = 491675480}, __glibc_reserved4 = 0,
__glibc_reserved5 = 0}
old_file_size = 17434080
#1 0x00000000001e66c4 in Fdump_emacs (filename=25845268, symfile=<optimized out>)
at emacs.c:2139
tem = 0
#2 0x000000000025bb4c in eval_sub (form=<optimized out>) at eval.c:2126
numargs = <optimized out>
args_left = 0
i = <optimized out>
maxargs = 2
argvals = {25857348, 25857316, 24384, 129, 7932928, 7932928, 7932928, 0}
fun = 4338869
val = <optimized out>
original_args = 14874147
count = <optimized out>
#3 0x000000000025be10 in Fprogn (body=<optimized out>) at eval.c:427
val = 0
#4 0x000000000025ba5c in eval_sub (form=<optimized out>) at eval.c:2085
numargs = <optimized out>
args_left = 14502707
i = <optimized out>
maxargs = <optimized out>
argvals = {8791798045857, 2472532, 0, 0, 1434632, 17026259, 8747139, 8622419}
fun = 7379453
val = <optimized out>
original_args = 14502707
count = <optimized out>
#5 0x000000000025ba5c in eval_sub (form=form <at> entry=12156979) at eval.c:2085
numargs = <optimized out>
args_left = 13550515
i = <optimized out>
maxargs = <optimized out>
argvals = {25259892, 44256, 0, 0, 0, 2, 38928, 24384}
fun = 7379549
val = <optimized out>
original_args = 13550515
count = <optimized out>
#6 0x000000000027f754 in readevalloop (readcharfun=readcharfun <at> entry=24384,
stream=stream <at> entry=0x825960, sourcename=sourcename <at> entry=8539236,
printflag=printflag <at> entry=false, unibyte=unibyte <at> entry=0, readfun=readfun <at> entry=0, start=0,
end=<optimized out>) at lread.c:1908
c = <optimized out>
val = <optimized out>
b = 0x0
continue_reading_p = true
lex_bound = <optimized out>
whole_buffer = false
first_sexp = <optimized out>
macroexpand = 0
#7 0x000000000027fc40 in Fload (file=8538980, noerror=<optimized out>, nomessage=0,
nosuffix=<optimized out>, must_suffix=<optimized out>) at lread.c:1316
stream = 0x825960
fd = <optimized out>
fd_index = 4
found = 8539172
efound = <optimized out>
hist_file_name = 8539236
newer = false
compiled = false
handler = <optimized out>
safe_p = true
fmode = 0x2f4128 "r"
version = 0
#8 0x000000000025baec in eval_sub (form=<optimized out>) at eval.c:2137
numargs = <optimized out>
args_left = 0
i = <optimized out>
maxargs = 5
argvals = {8538980, 0, 0, 0, 0, 8540208, 8791798047201, -140733123707272}
fun = 7386853
val = <optimized out>
original_args = 8476163
count = <optimized out>
#9 0x000000000025ef3c in Feval (form=<optimized out>, lexical=0) at eval.c:1953
No locals.
#10 0x000000000025aca4 in internal_condition_case (bfun=bfun <at> entry=0x1eaf14 <top_level_2>,
handlers=handlers <at> entry=18912, hfun=hfun <at> entry=0x1ef784 <cmd_error>) at eval.c:1309
val = <optimized out>
c = <optimized out>
#11 0x00000000001ed3a4 in top_level_1 (ignore=ignore <at> entry=0) at keyboard.c:1103
ignore = 0
#12 0x000000000025aba8 in internal_catch (tag=tag <at> entry=45648,
func=func <at> entry=0x1ed33c <top_level_1>, arg=arg <at> entry=0) at eval.c:1073
val = <optimized out>
c = <optimized out>
#13 0x00000000001eaea4 in command_loop () at keyboard.c:1064
No locals.
#14 0x00000000001ef34c in recursive_edit_1 () at keyboard.c:671
val = <optimized out>
#15 0x00000000001ef6f4 in Frecursive_edit () at keyboard.c:742
buffer = <optimized out>
#16 0x0000000000112d38 in main (argc=<optimized out>, argv=0x7fefffff348) at emacs.c:1652
dummy = 1058888
stack_bottom_variable = 1 '\001'
do_initial_setlocale = <optimized out>
dumping = <optimized out>
skip_args = 3
rlim = {rlim_cur = 8720000, rlim_max = 18446744073709551615}
no_loadup = <optimized out>
junk = 0x0
dname_arg = 0x0
ch_to_dir = 0x0
original_pwd = <optimized out>
In GNU Emacs 24.5.1 (sparc64-unknown-linux-gnu, X toolkit, Xaw3d scroll bars)
of 2015-11-29 on sparky, modified by Debian
System Description: Debian GNU/Linux unstable (sid)
Configured using:
`configure --build sparc64-linux-gnu --prefix=/usr
--sharedstatedir=/var/lib --libexecdir=/usr/lib
--localstatedir=/var/lib --infodir=/usr/share/info
--mandir=/usr/share/man --with-pop=yes
--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.5/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.5/site-lisp:/usr/share/emacs/site-lisp
--build sparc64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib
--libexecdir=/usr/lib --localstatedir=/var/lib
--infodir=/usr/share/info --mandir=/usr/share/man --with-pop=yes
--enable-locallisppath=/etc/emacs24:/etc/emacs:/usr/local/share/emacs/24.5/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/24.5/site-lisp:/usr/share/emacs/site-lisp
--with-x=yes --with-x-toolkit=lucid --with-toolkit-scroll-bars
--without-gconf --without-gsettings 'CFLAGS=-g -O2
-fstack-protector-strong -Wformat -Werror=format-security -Wall'
CPPFLAGS=-D_FORTIFY_SOURCE=2 LDFLAGS=-Wl,-z,relro'
Important settings:
value of $LANG: en_SG.UTF-8
locale-coding-system: utf-8-unix
Major mode: Fundamental
Minor modes in effect:
tooltip-mode: t
electric-indent-mode: t
mouse-wheel-mode: t
tool-bar-mode: t
menu-bar-mode: t
file-name-shadow-mode: t
global-font-lock-mode: t
auto-composition-mode: t
auto-encryption-mode: t
auto-compression-mode: t
buffer-read-only: t
line-number-mode: t
transient-mark-mode: t
Recent messages:
Loading /etc/emacs/site-start.d/50dictionaries-common.el (source)...
Loading debian-ispell...
Loading /var/cache/dictionaries-common/emacsen-ispell-default.el (source)...done
Loading debian-ispell...done
Loading /var/cache/dictionaries-common/emacsen-ispell-dicts.el (source)...done
Loading /etc/emacs/site-start.d/50dictionaries-common.el (source)...done
Loading /etc/emacs/site-start.d/50gtk-doc-tools.el (source)...done
Loading term/xterm...done
For information about GNU Emacs and the GNU system, type C-h C-a.
Making completion list... [2 times]
Load-path shadows:
/usr/share/emacs/24.5/site-lisp/debian-startup hides /usr/share/emacs/site-lisp/debian-startup
Features:
(shadow sort gnus-util mail-extr emacsbug message format-spec rfc822 mml
mml-sec mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev
gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util
help-fns mail-prsvr mail-utils help-mode easymenu xterm time-date
tooltip electric uniquify ediff-hook vc-hooks lisp-float-type mwheel
x-win x-dnd tool-bar dnd fontset image regexp-opt fringe tabulated-list
newcomment lisp-mode prog-mode register page menu-bar rfn-eshadow timer
select scroll-bar mouse jit-lock font-lock syntax facemenu font-core
frame cham georgian utf-8-lang misc-lang vietnamese tibetan thai
tai-viet lao korean japanese hebrew greek romanian slovak czech european
ethiopic indian cyrillic chinese case-table epa-hook jka-cmpr-hook help
simple abbrev minibuffer nadvice loaddefs button faces cus-face macroexp
files text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote make-network-process
dbusbind gfilenotify dynamic-setting font-render-setting x-toolkit x
multi-tty emacs)
Memory information:
((conses 16 75135 5336)
(symbols 48 17800 0)
(miscs 40 73 113)
(strings 32 9429 3746)
(string-bytes 1 258369)
(vectors 16 7222)
(vector-slots 8 342728 32825)
(floats 8 66 291)
(intervals 56 208 22)
(buffers 960 14)
(heap 1024 8358 811))
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1994-97 Ian Jackson.