On Monday 16 March 2015 10:16:37 Christopher Covington wrote: > > On 03/11/2015 08:47 AM, Arnd Bergmann wrote: > > On Wednesday 11 March 2015 06:24:16 Alexander Graf wrote: > >> So after recompiling all of the distribution with newer binutils we now > >> have an openSUSE Factory tree that has 64k aligned 32bit binaries. > >> > >> Unfortunately however, the 32bit glibc has a bogus mmap() implementation > >> that hard codes 4k page size. > >> > >> With the patch below applied to glibc, I can successfully run 32bit user > >> space on Seattle with 64k PAGE_SIZE though. So I guess we'll need to fix > >> up glibc next. > >> > >> Do you know of anyone who's fluent enough in 32bit ARM assembly to > >> convert the hard coded assumptions in there to instead use a variable > >> that takes the actual host page size into account? > > > > I believe this is a kernel bug, and the kernel API for 32-bit emulation > > should always take the pgoff argument in 4KB units instead of PAGE_SIZE > > units, see the implementation of sys_mmap2 in > > arch/powerpc/kernel/sys_ppc32.c. > > > > All user space programs that call mmap2 still need to make sure that > > their arguments are PAGE_SIZE aligned, but the libc need not care > > about this here. > > What is the correct behavior for /proc/pid/pagemap, /proc/kpagecount, and > /proc/kpageflags for a AArch32 process running on an AArch64 kernel with > non-4K translation granule? Actual page frame number or units-of-4K frame > number? >
Not sure, see what PowerPC does in that case. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/