Combination of large pages and fully static does not work

[suresh-srinivas]

./configure --fully-static --use-largepages
labuser@y004:~/ssuresh/node-ssuresh$ ./node
Illegal instruction (core dumped)

I debugged this problem and when we use --fully-static, the .text segment contains libc code for mmap. This is one of the functions that is called during the actual moving of the TextRegion and one of the requirement was to not have any functions that are called in MoveTextRegionToLargePages themselves being moved.

#0  0x00000000017690c0 in mmap64 ()
#1  0x000000000060006f in node::MoveTextRegionToLargePages(node::text_region const&) ()
#2  0x000000000078519e in node::MapStaticCodeToLargePages() ()

I have a fix/workaround for it by moving all of the static code libc into the .lpstub region. Another potential fix is to use the SYSCALL interface to call the mmap, I havent tried that yet.

I will send a PR with the fix. @refack @uttampawar @gireeshpunathil @lundibundi @addaleax

• Version: master
• Platform: Linux
• Subsystem: src

[bnoordhuis]

Another potential fix is to use the SYSCALL interface to call the mmap

syscall() is implemented in glibc and musl as a function, not a macro, so you'd have the same issue.

You can of course use inline assembly but then you need to write that for each supported architecture.