On 11/18/2016 05:34 PM, Jeremy Linton wrote:
On 11/18/2016 04:29 PM, Jeremy Linton wrote:
The current RHELSA kernel is using a 42bit VA which is too limiting for possible near future workloads. Update this to 48 bits. This patch has a dependency on mozjs versions in the distro being patched to work with virtual address spaces >47 bits.
Just a quick comment. An easy way to verify that the kernel in use has 48bit VA's is to check the /proc/xxx/maps of a userspace process.
A 48bit VA kernel will place shared libraries into addresses at the top of the userspace address region. For example:
ffffacbb0000-ffffacbc0000 r-xp 00000000 103:04 33858952 /usr/lib64/libnss_files-2.17.so ffffacbc0000-ffffacbd0000 r--p 00000000 103:04 33858952 /usr/lib64/libnss_files-2.17.so ffffacbd0000-ffffacbe0000 rw-p 00010000 103:04 33858952 /usr/lib64/libnss_files-2.17.so ffffacbf0000-ffffacc30000 r-xp 00000000 103:04 33644605 /usr/lib64/libpcre.so.1.2.0 ffffacc30000-ffffacc40000 r--p 00030000 103:04 33644605 /usr/lib64/libpcre.so.1.2.0 ffffacc40000-ffffacc50000 rw-p 00040000 103:04 33644605 /usr/lib64/libpcre.so.1.2.0
How does GNU ld determine VA bits?
Thanks, Cov