Re: Help needed to track down bug: linking Linux kernel with gold creates unbootable kernel

[Ian Lance Taylor <iant at google dot com>]

"H.J. Lu" <hjl.tools@gmail.com> writes:

> 2MB maximum page size may have a bigger gap between PT_LOAD
> segment in memory than 4KB maximum page size. But it doesn't necessarily
> use more memory nor disk space. Since x86_64 is 64bit, address
> space shouldn't be an issue in vast majority cases. I'd like to hear
> a case to say otherwise.

The increased use of address space was an issue with x86_64 binaries
which opened hundreds of shared libraries.  Each shared library was
burning 2 megabytes of address space between the text and data
segments.  This in turn caused trouble with setting limits on the
amount of virtual memory which could be allocated: greatly increasing
the limits to permit hundreds of shared libraries meant that the
limits were unreasonably high for programs with only a couple of
shared libraries.  This was a problem we found with GNU ld a while
back.  While other workarounds were possible, using -z max-page-size
was a simple one.  I didn't see any reason to carry that problem
forward with gold, given that extremely few programs need -z
max-page-size larger than 0x1000 on x86_64.

Ian