Re: ptrace single-stepping change breaks Wine

From: Ingo Molnar
Date: Wed Jan 05 2005 - 06:28:22 EST



* Thomas Sailer <sailer@xxxxxx> wrote:

> > I'm afraid Alexandre has decided not to apply this patch (the ABI
> > personality syscall). His reasoning is as follows:
>
> Quite understandably.

another workaround to switch off flex-mmap is to set the stack ulimit to
'unlimited':

saturn:~> cat /proc/self/maps | tail -7
b7db3000-b7db4000 r--p 00cfd000 03:41 3735973 /usr/lib/locale/locale-archive
b7db4000-b7de1000 r--p 00ccc000 03:41 3735973 /usr/lib/locale/locale-archive
b7de1000-b7de7000 r--p 00cc3000 03:41 3735973 /usr/lib/locale/locale-archive
b7de7000-b7fe7000 r--p 00000000 03:41 3735973 /usr/lib/locale/locale-archive
b7fe7000-b7fe8000 rw-p b7fe7000 00:00 0
bff2c000-c0000000 rw-p bff2c000 00:00 0
ffffe000-fffff000 ---p 00000000 00:00 0

saturn:~> ulimit -s unlimited

saturn:~> cat /proc/self/maps | tail -7
42188000-4218a000 rw-p 00014000 03:41 3433982 /lib/ld-2.3.3.so
4218c000-422aa000 r-xp 00000000 03:41 3434006 /lib/tls/libc-2.3.3.so
422aa000-422ac000 r--p 0011d000 03:41 3434006 /lib/tls/libc-2.3.3.so
422ac000-422ae000 rw-p 0011f000 03:41 3434006 /lib/tls/libc-2.3.3.so
422ae000-422b0000 rw-p 422ae000 00:00 0
bfea0000-c0000000 rw-p bfea0000 00:00 0
ffffe000-fffff000 ---p 00000000 00:00 0

e.g. SuSE defaults to an unlimited stack so flex-mmap is effectively
disabled there.

To set the VM to legacy, for all apps, set /proc/sys/vm/legacy_va_layout
to 1.

Ingo
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