Hi, Jeff Dike wrote: > On Wed, Apr 04, 2007 at 06:13:45PM +0200, Nicolas Boullis wrote: > >>OK, I just built a 2.6.20.4 UML kernel, and at first sight it seems to >>run fine with size=2048M. (With higher values, it still seems fine with >>size=2800M, and completely fails to boot with size=2900M or higher.) > > > It's occupying pretty much its entire address space at that point, so it's > not surprising that it stops working around 3G, except that better > diagnostics (or just trimming memory to fir) would be a good thing.
After some more tests, it seems that there are two limits, and at least one of them is a moving target. Trying to find the limit it first worked fine with size=2500M, and later failed with the same value. With low enough values (current limit is somewhere below 2500M), il seems to work fine. With large enough values (moving target as well, somthing around mem=2820M) it does not boot at all, and fail after a few lines with a segfault: Checking that ptrace can change system call numbers...OK Checking syscall emulation patch for ptrace...OK Checking advanced syscall emulation patch for ptrace...OK Checking for tmpfs mount on /dev/shm...OK Checking PROT_EXEC mmap in /dev/shm/...OK Checking for the skas3 patch in the host: - /proc/mm...not found - PTRACE_FAULTINFO...not found - PTRACE_LDT...not found UML running in SKAS0 mode -su: line 1: 7274 Segmentation fault With intermediate values, it fails with a soft lockup, as 2 mails ago. I have no idea how/what to investigate further... Cheers, Nicolas ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ User-mode-linux-user mailing list User-mode-linux-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user
