We would like to avoid statically defining any specific page size on aarch64-gnu, and instead make sure that everything uses the dynamic page size, available via vm_page_size and GLRO(dl_pagesize).
There are currently a few places in glibc that require EXEC_PAGESIZE to be defined. Per Roland's suggestion [0], drop the static GLRO(dl_pagesize) initializers (for now, only if EXEC_PAGESIZE is not defined), and don't require EXEC_PAGESIZE definition for libio to enable mmap usage. [0]: https://mail.gnu.org/archive/html/bug-hurd/2011-10/msg00035.html Signed-off-by: Sergey Bugaev <buga...@gmail.com> --- I opted to play it safe and only disable the static GLRO(dl_pagesize) initializers when EXEC_PAGESIZE is not defined (i.e. on aarch64-gnu). I can change this to be unconditional if that's considered OK. elf/dl-support.c | 6 +++++- elf/rtld.c | 2 ++ libio/libioP.h | 2 +- 3 files changed, 8 insertions(+), 2 deletions(-) diff --git a/elf/dl-support.c b/elf/dl-support.c index 2f502c8b..6375dc95 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -135,7 +135,11 @@ void *_dl_random; #include <dl-procruntime.c> #include <dl-procinfo.c> -size_t _dl_pagesize = EXEC_PAGESIZE; +size_t _dl_pagesize +#ifdef EXEC_PAGESIZE + = EXEC_PAGESIZE +#endif +; size_t _dl_minsigstacksize = CONSTANT_MINSIGSTKSZ; diff --git a/elf/rtld.c b/elf/rtld.c index 4f494b79..98b042c0 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -358,7 +358,9 @@ struct rtld_global_ro _rtld_global_ro attribute_relro = ._dl_debug_fd = STDERR_FILENO, ._dl_lazy = 1, ._dl_fpu_control = _FPU_DEFAULT, +#ifdef EXEC_PAGESIZE ._dl_pagesize = EXEC_PAGESIZE, +#endif ._dl_inhibit_cache = 0, ._dl_profile_output = "/var/tmp", diff --git a/libio/libioP.h b/libio/libioP.h index 1af287b1..1a7f547e 100644 --- a/libio/libioP.h +++ b/libio/libioP.h @@ -852,7 +852,7 @@ extern off64_t _IO_seekpos_unlocked (FILE *, off64_t, int) # define MAP_ANONYMOUS MAP_ANON # endif -# if !defined(MAP_ANONYMOUS) || !defined(EXEC_PAGESIZE) +# if !defined(MAP_ANONYMOUS) # undef _G_HAVE_MMAP # define _G_HAVE_MMAP 0 # endif -- 2.43.0
