@@ -149,14 +149,6 @@ emit_weak_aliases()
echo "$calls" |
while read file srcfile caller syscall args strong weak; do
- vdso_syscall=
- case x"$syscall" in
- *:*@*)
- vdso_syscall="${syscall#*:}"
- syscall="${syscall%:*}"
- ;;
- esac
-
case x"$syscall" in
x-) callnum=_ ;;
*)
@@ -233,10 +225,9 @@ while read file srcfile caller syscall args strong weak; do
if test $shared_only = t; then
# The versioned symbols are only in the shared library.
echo "shared-only-routines += $file"
- test -n "$vdso_syscall" || echo "\$(objpfx)${file}.os: \\"
+ echo "\$(objpfx)${file}.os: \\"
else
object_suffixes='$(object-suffixes)'
- test -z "$vdso_syscall" || object_suffixes='$(object-suffixes-noshared)'
echo "\
\$(foreach p,\$(sysd-rules-targets),\
\$(foreach o,${object_suffixes},\$(objpfx)\$(patsubst %,\$p,$file)\$o)): \\"
@@ -268,40 +259,6 @@ while read file srcfile caller syscall args strong weak; do
echo ' ) | $(compile-syscall) '"\
\$(foreach p,\$(patsubst %$file,%,\$(basename \$(@F))),\$(\$(p)CPPFLAGS))"
- if test -n "$vdso_syscall"; then
- # In the shared library, we're going to emit an IFUNC using a vDSO function.
- # $vdso_syscall looks like "name@KERNEL_X.Y" where "name" is the symbol
- # name in the vDSO and KERNEL_X.Y is its symbol version.
- vdso_symbol="${vdso_syscall%@*}"
- vdso_symver="${vdso_syscall#*@}"
- vdso_symver=`echo "$vdso_symver" | sed 's/\./_/g'`
- cat <<EOF
-
-\$(foreach p,\$(sysd-rules-targets),\$(objpfx)\$(patsubst %,\$p,$file).os): \\
- \$(..)sysdeps/unix/make-syscalls.sh
- \$(make-target-directory)
- (echo '#define ${strong} __redirect_${strong}'; \\
- echo '#include <dl-vdso.h>'; \\
- echo '#undef ${strong}'; \\
- echo '#define vdso_ifunc_init()'; \\
- echo '__ifunc (__redirect_${strong}, ${strong},'; \\
- echo ' get_vdso_symbol ("${vdso_symbol}"), void,'; \\
- echo ' vdso_ifunc_init)'; \\
-EOF
- # This is doing "hidden_def (${strong})", but the compiler
- # doesn't know that we've defined ${strong} in the same file, so
- # we can't do it the normal way.
- cat <<EOF
- echo 'asm (".globl __GI_${strong}");'; \\
- echo 'asm ("__GI_${strong} = ${strong}");'; \\
-EOF
- emit_weak_aliases
- cat <<EOF
- ) | \$(compile-stdin.c) \
-\$(foreach p,\$(patsubst %$file,%,\$(basename \$(@F))),\$(\$(p)CPPFLAGS))
-EOF
- fi
-
if test $shared_only = t; then
# The versioned symbols are only in the shared library.
echo endif
The auto-generated vDSO call shows some issues: - It requires sync the auto-generated C file with current glibc implementation; - It still uses symbol redirections hacks where libc-symbols.h provide macros that uses compiler builtins (libc_ifunc_redirected for instance); - It does not handle all required compiler handling (inhibit_stack_protector on iFUNC resolver). - No architecure uses it. Checked with a build against all major ABIs. --- sysdeps/unix/make-syscalls.sh | 45 +---------------------------------- 1 file changed, 1 insertion(+), 44 deletions(-) -- 2.17.1