В сообщении от Четверг 13 мая 2010 10:40:37 автор Martin Jansa написал: > On Thu, May 13, 2010 at 09:53:54AM +0400, Roman I Khimov wrote: > > В сообщении от Четверг 13 мая 2010 01:30:53 автор Robert P. J. Day написал: > > > * on http://wiki.openembedded.net/index.php/OEandYourDistro#Ubuntu, > > > there's a reference to configuring for qemu-arm: > > > > > > echo 128 > /proc/sys/vm/mmap_min_addr > > > > > > from memory, i always simply set that to zero on fedora. is there > > > something magic about the value 128? at the moment, it's at the > > > default value of 65536 on this ubuntu system. > > > > With current qemu in OE mmap_min_addr tricks are not needed at all. > > On some systems (I have report from fedora and kubuntu) it still needs 0 > in mmap_min_addr :/. > > Investigating why, but it's slow because it doesn't fail on my box. > > My guess is that this chunk from > http://git.qemu.org/qemu.git/tree/linux-user/main.c > cannot work on systems where normal user is not allowed to read > /proc/sys/vm/mmap_min_addr and mmap_min_addr is not initialized with > sane value.
Just checked with Ubuntu and Fedora, it really isn't possible to read /proc/sys/vm/mmap_min_addr as regular user, although it has 644 permissions on it. "Security"? Damn. [after 15 minutes] OK, actually there is a useful entry on Launchpad: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/568844 The real solution is in the kernel, it should be fixed for latest Ubuntu and hopefully Fedora will catch up on this issue too. http://git.kernel.org/?p=linux/kernel/git/jmorris/security- testing-2.6.git;a=commitdiff;h=822cceec7248013821d655545ea45d1c6a9d15b3 Interesting that openSUSE with 2.6.31 kernel doesn't have such problems... And our main build machine with Debian stable + 2.6.30 kernel works fine too. Probably this check got introduced in 2.6.32. Well, as the problem is in the kernel really, I think everyone having this problem should push distro maintainers to update kernels with the tiny fix mentioned above. But as a workaround, yep, "0" setting might work (beware that it might also not work as in here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/423513 ). _______________________________________________ Openembedded-devel mailing list [email protected] http://lists.linuxtogo.org/cgi-bin/mailman/listinfo/openembedded-devel
