On Sun, Apr 01, 2007 at 09:10:02AM -0400, Jeff Dike wrote: > On Sun, Apr 01, 2007 at 07:45:47AM +0200, jez wrote: > > Yep, that's an improvement alright. I changed the address prefix from > > 0xbf down to 0xbb on the stub defaults and now I'm getting: > > > > -- Output -- > > EXT3-fs: mounted filesystem with ordered data mode. > > VFS: Mounted root (ext3 filesystem) readonly. > > line_ioctl: tty0: ioctl KDSIGACCEPT called > > INIT: version 2.86 booting > > *** glibc detected *** double free or corruption (!prev): 0x08051068 *** > > -- End -- > > Hmm, I've never seen that before. >
It's quite odd. I also tried using 0x60 and also putting them between the stack and the end of user-space mem at 0xbfafe000. Each time I get the same error, with the same address, 0x08051068. -- Output -- (gdb) x 0x08051068 0x8051068 <alloc_node_mem_map+72>: 0xac868bc3 (gdb) disassemble 0x08051068 Dump of assembler code for function alloc_node_mem_map: ... 0x08051068 <alloc_node_mem_map+72>: ret ... -- End -- I've tried rebooting the outer UML, and I also tried statically compiling the inner UML. No change yet though. Hey, at least it's consistant :-). > > > ... or it needs to be something that can be set from the command line. > > > > You mean so that all UMLs could be used something like: > > > > ./vmlinux --level 1 > > Yeah, CONFIG_STUB_* would turn into something like > CONFIG_STUB_* -level*2*PAGE_SIZE > Now here's something strange. I initially assumed that there were only two pages, so when I was changing the stub mappings, I first tried: CONFIG_STUB_CODE=0xbfffc000 CONFIG_STUB_DATA=0xbfffd000 CONFIG_STUB_START=0xbfffc000 What's wired is that this returns the mmap error: mapping mmap stub failed, errno = 12 Kernel panic - not syncing: start_userspace : expected SIGSTOP, got status = 256 This got me to thinking that maybe the CONFIG_STUB_START indicated the top of a downward-growing stack or something. Are you saying that these pages should actually be free, or have I just misunderstood? ------------------------------------------------------------------------- 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 [email protected] https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user
