diff options
Diffstat (limited to 'sysdeps/s390/s390-64/configure.ac')
| -rw-r--r-- | sysdeps/s390/s390-64/configure.ac | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/sysdeps/s390/s390-64/configure.ac b/sysdeps/s390/s390-64/configure.ac new file mode 100644 index 0000000000..2583a4a335 --- /dev/null +++ b/sysdeps/s390/s390-64/configure.ac @@ -0,0 +1,92 @@ +GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory. +# Local configure fragment for sysdeps/s390/s390-64. + +# Minimal checking for static PIE support in ld. +# Compare to ld testcase/bugzilla: +# <binutils-source>/ld/testsuite/ld-elf/pr22263-1.rd +AC_CACHE_CHECK([for s390-specific static PIE requirements], \ +[libc_cv_s390x_staticpie_req], [dnl + cat > conftest1.c <<EOF +__thread int * foo; + +void +bar (void) +{ + *foo = 1; +} +EOF + cat > conftest2.c <<EOF +extern __thread int *foo; +extern void bar (void); +static int x; + +int +main () +{ + foo = &x; + return 0; +} +EOF + libc_cv_s390x_staticpie_req=no + if AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -fPIE -c conftest1.c -o conftest1.o]) \ + && AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -fPIE -c conftest2.c -o conftest2.o]) \ + && AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS $LDFLAGS -pie -o conftest conftest1.o conftest2.o]) \ + && AC_TRY_COMMAND([! readelf -Wr conftest | grep R_390_TLS_TPOFF]) + then + libc_cv_s390x_staticpie_req=yes + fi + rm -rf conftest.*]) +if test $libc_cv_s390x_staticpie_req = yes; then + # Static PIE is supported only on 64bit. + # Ensure you also have those patches for: + # - binutils (ld) + # - "[PR ld/22263] s390: Avoid dynamic TLS relocs in PIE" + # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=26b1426577b5dcb32d149c64cca3e603b81948a9 + # (Tested by configure check above) + # Otherwise there will be a R_390_TLS_TPOFF relocation, which fails to + # be processed in _dl_relocate_static_pie() as static TLS map is not setup. + # - "s390: Add DT_JMPREL pointing to .rela.[i]plt with static-pie" + # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d942d8db12adf4c9e5c7d9ed6496a779ece7149e + # (We can't test it in configure as we are not able to link a static PIE + # executable if the system glibc lacks static PIE support) + # Otherwise there won't be DT_JMPREL, DT_PLTRELA, DT_PLTRELASZ entries + # and the IFUNC symbols are not processed, which leads to crashes. + # + # - kernel (the mentioned links to the commits belong to 5.19 merge window): + # - "s390/mmap: increase stack/mmap gap to 128MB" + # https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=f2f47d0ef72c30622e62471903ea19446ea79ee2 + # - "s390/vdso: move vdso mapping to its own function" + # https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=57761da4dc5cd60bed2c81ba0edb7495c3c740b8 + # - "s390/vdso: map vdso above stack" + # https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=9e37a2e8546f9e48ea76c839116fa5174d14e033 + # - "s390/vdso: add vdso randomization" + # https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=41cd81abafdc4e58a93fcb677712a76885e3ca25 + # (We can't test the kernel of the target system) + # Otherwise if /proc/sys/kernel/randomize_va_space is turned off (0), + # static PIE executables like ldconfig will crash. While startup sbrk is + # used to enlarge the HEAP. Unfortunately the underlying brk syscall fails + # as there is not enough space after the HEAP. Then the address of the TLS + # image is invalid and the following memcpy in __libc_setup_tls() leads + # to a segfault. + # If /proc/sys/kernel/randomize_va_space is activated (default: 2), there + # is enough space after HEAP. + # + # - glibc + # - "Linux: Define MMAP_CALL_INTERNAL" + # https://sourceware.org/git/?p=glibc.git;a=commit;h=c1b68685d438373efe64e5f076f4215723004dfb + # - "i386: Remove OPTIMIZE_FOR_GCC_5 from Linux libc-do-syscall.S" + # https://sourceware.org/git/?p=glibc.git;a=commit;h=6e5c7a1e262961adb52443ab91bd2c9b72316402 + # - "i386: Honor I386_USE_SYSENTER for 6-argument Linux system calls" + # https://sourceware.org/git/?p=glibc.git;a=commit;h=60f0f2130d30cfd008ca39743027f1e200592dff + # - "ia64: Always define IA64_USE_NEW_STUB as a flag macro" + # https://sourceware.org/git/?p=glibc.git;a=commit;h=18bd9c3d3b1b6a9182698c85354578d1d58e9d64 + # - "Linux: Implement a useful version of _startup_fatal" + # https://sourceware.org/git/?p=glibc.git;a=commit;h=a2a6bce7d7e52c1c34369a7da62c501cc350bc31 + # - "Linux: Introduce __brk_call for invoking the brk system call" + # https://sourceware.org/git/?p=glibc.git;a=commit;h=b57ab258c1140bc45464b4b9908713e3e0ee35aa + # - "csu: Implement and use _dl_early_allocate during static startup" + # https://sourceware.org/git/?p=glibc.git;a=commit;h=f787e138aa0bf677bf74fa2a08595c446292f3d7 + # The mentioned patch series by Florian Weimer avoids the mentioned failing + # sbrk syscall by falling back to mmap. + AC_DEFINE(SUPPORT_STATIC_PIE) +fi |