On Thu, Dec 26, 2013 at 9:58 AM, H. Peter Anvin <h...@zytor.com> wrote: > On 12/26/2013 05:52 AM, H.J. Lu wrote: >> >>> c) why you suddenly need these changes now and not when the x32 ABI >>> support was submitted and hopefully heavily tested >> >> Kernel headers had been wrong for -m32/-mx32 on x86-64 >> for a long long time. Linux/x86-64 normally use header >> files from glibc, which avoids broken kernel header files. >> Kernel uabi header files fix -m32, but not -mx32, which I am >> working on now. >> > > In other words, this work is really part of making *libc make use the > kernel uabi headers, which is a valuable work. The fact that the kernel > headers never got fully ported to x32 is a big reason why x32 is still > labeled experimental. > > MIPS N32 and ARM64 ILP32 are x32-like ABIs which of course need to not > be broken. However, currently __kernel_[u]long_t is [unsigned] long for > all ABIs other than x32, so changing [unsigned] long to > __kernel_[u]long_t will be a null change for anything but x32. They > perhaps *SHOULD* be different for N32 or ARM64 ILP32, but that is for > those arch maintainers to set. > > However, I believe H.J.'s patches from this morning conditionalizing > this on __BITS_PER_LONG are just plain wrong.
FWIW, I prefer my first alternative. I only added the second one since I can't test for other ABIs. I am enclosing my kernel header file checker. It compares kernel header files against glibc header files for -m64, -m32 and -mx32. -- H.J.
kernel-headers.tar.xz
Description: application/xz
