lkml.org 
[lkml]   [2003]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
Subject[BUG] 2.5.62 kmod rewrite broke modprobe's install command
In kernel 2.5.62, modprobe logs "FATAL: Error -1" when invoked
via request_module() to run a trivial /bin/true "install" command.
This problem did not exist in 2.5.61 or earlier kernels.

Repeat-by: Build a kernel without the RTC driver, put
"install char-major-10-135 /bin/true" in /etc/modprobe.conf
(new ugly way of saying "alias ... off"), od -c /dev/rtc,
and observe the modprobe error in /var/log/messages.
This will trigger the problem with 100% repeatability for me.

The reason this happens is that in 2.5.62, modprobe is started
with SIGCHLD set to SIG_IGN and not blocked. The "install"
command is run by system(), but due to SIGCHLD being SIG_IGN,
the child (which terminates quickly) is reaped automatically.
The parent process (modprobe) does a wait or waitpid, which fails
with ECHILD since the child is already gone. system() returns -1,
and modprobe logs a fatal error.

In 2.5.61 and earlier kernels, modprobe is started with SIGCHLD
set to SIG_DFL and not blocked, and system() works normally.

/Mikael
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:33    [W:0.028 / U:1.676 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site