Sreadahead fails to generate a pack file with nullmailer installed (blocking on a FIFO)

[Aaron Haviland]

Binary package hint: sreadahead

Currently using Karmic, sreadahead 1.0-5

It's taken a while to diagnose this, but it seems that installing nullmailer prevents sreadahead from generating a pack file.

Specifically, when sreadahead receives SIGTERM, and is doing that stage, I can *always* get a backtrace in gdb that points to /var/spool/nullmailer/trigger:

#0 0x005db416 in __kernel_vsyscall ()
#1 0x00bdf843 in __open_nocancel () from /lib/tls/i686/cmov/libc.so.6
#2 0x00b8a96f in *__GI__IO_file_open (fp=0x872a008, filename=0x1b6 <Address 0x1b6 out of bounds>, posix_mode=0, prot=0, read_write=8, is32not64=1) at fileops.c:231
#3 0x00b8ab18 in _IO_new_file_fopen (fp=0x872a008, filename=0x87f6b30 "/var/spool/nullmailer/trigger", mode=<value optimized out>, is32not64=1) at fileops.c:335
#4 0x00b7ee4d in __fopen_internal (filename=0x87f6b30 "/var/spool/nullmailer/trigger", mode=0x804a26f "r", is32=1) at iofopen.c:93
#5 0x00b7eeac in _IO_new_fopen (filename=0x87f6b30 "/var/spool/nullmailer/trigger", mode=0x804a26f "r") at iofopen.c:107
#6 0x08049906 in ?? ()
#7 <signal handler called>
#8 0x005db416 in __kernel_vsyscall ()
#9 0x00f4b5f6 in __pause_nocancel () from /lib/tls/i686/cmov/libpthread.so.0
#10 0x08049ec5 in ?? ()
#11 0x00b39b56 in __libc_start_main (main=0x8049d23, argc=4, ubp_av=0xbffff814, init=0x804a030, fini=0x804a020, rtld_fini=0xdb3d20 <_dl_fini>, stack_end=0xbffff80c) at libc-start.c:220
#12 0x08048fb1 in ?? ()

Where /var/spool/nullmailer/trigger is:

orion@eris:~$ file /var/spool/nullmailer/trigger
/var/spool/nullmailer/trigger: fifo (named pipe)
orion@eris:~$ stat /var/spool/nullmailer/trigger
  File: `/var/spool/nullmailer/trigger'
  Size: 0 Blocks: 0 IO Block: 4096 fifo
Device: 805h/2053d Inode: 419790 Links: 1
Access: (0622/prw--w--w-) Uid: ( 8/ mail) Gid: ( 0/ root)
Access: 2009-10-26 21:05:17.592778891 -0400
Modify: 2009-10-26 21:05:17.592778891 -0400
Change: 2009-10-26 21:05:17.602780811 -0400

[Scott James Remnant (Canonical) (canonical-scott)]

ureadahead tries a bit harder not to open() fifos

[Scott James Remnant (Canonical) (canonical-scott)]

ureadahead has now replaced sreadahead in both karmic (via -updates) and lucid