On Thu, 19 Dec 2013 16:02:19 +0100 (CET) Jiri Kosina <jkosina@xxxxxxx> wrote: > On Thu, 19 Dec 2013, Timo Teras wrote: > > > As you see, the main executable is mapped 57620000-57708000 and > > 57708000-5770a000. Heap follow immediately after that > > 5770a000-5770c000 followed by anything mmaped after it (stack or > > some other libraries). Heap can grow only up to 5ffdf000 meaning the > > application is limited to 140 megs or so in this instance. This > > limit can go much lower depending how the randomization went. And > > even 140 megs is very little for big apps. > > So what is the real problem again (i.e. the actual symptoms), please? > Is it that your userspace memory allocator doesn't use mmap() for > allocations at all? Random application failures with uclibc and musl c-libraries. Both seem to use mmap() for large allocations, and brk() for small ones. IIRC, there was also some minor breakage with other applications that use brk() to do some self-accounting / other funny stuff. While this is not strictly a bug, I would still hope that the memory layout is configured for maximum compatibility... or do you see it introducing unwanted side effects? -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html