On 01/10/2015 03:09 PM, Richard Weinberger wrote: > > > Am 10.01.2015 um 15:07 schrieb Toralf Förster: >> On 01/06/2015 12:45 AM, Richard Weinberger wrote: >>> On Tue, Jun 24, 2014 at 10:52 PM, Toralf Förster wrote: >>>> IIRC in former times I could assign an UML instance 2047M, but nowadays >>>> even 2044M is too big. >>> >>> This depends on the host side. UML heavily depends on the host memory layout. >>> Now with ASLR and such stuff the layout changes and the boarder for >>> UML are no longer constant. >>> Daniel and I currently hunt down such an issue. >>> What exactly happens if your give UML too much memory? >>> >> >> tfoerste@n22 ~ $ start_uml.sh -r trinity >> + /home/tfoerste/devel/linux/linux earlyprintk ubda=/home/tfoerste/virtual/uml/trinity ubdb=/mnt/ramdisk/trinity_swap eth0=tuntap,tap0,72:ef:3d:9f:c3:5a mem=2044M con0=fd:0,fd:1 con=pts umid=uml_trinity rootfstype=ext4 softlockup_all_cpu_backtrace=1 >> Locating the bottom of the address space ... 0x1000 >> Locating the top of the address space ... 0xc0000000 >> Core dump limits : >> soft - 0 >> hard - NONE >> 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 environment variables for a tempdir...none found >> Checking if /dev/shm is on tmpfs...OK >> Checking PROT_EXEC mmap in /dev/shm...OK >> Checking for the skas3 patch in the host: >> - /proc/mm...not found: No such file or directory >> - PTRACE_FAULTINFO...not found >> - PTRACE_LDT...not found >> UML running in SKAS0 mode >> Adding 12328960 bytes to physical memory to account for exec-shield gap >> write: File too large >> > > Does this *always* happen? > > Please also attach your current .config. > > Thanks, > //richard > yes, it never worked with values above 2026M (tested at an old ThinkPad T420, running a 32 bit Gentoo Linux with host kernel 3.17.4 ) -- Toralf pgp key: 7B1A 07F4 EC82 0F90 D4C2 8936 872A E508 0076 E94E