From: Adhemerval Zanella <adhemerval.zanella@linaro.org>
To: libc-alpha@sourceware.org
Subject: [PATCH 03/16] Remove vDSO support from make-syscall.sh
Date: Tue, 17 Dec 2019 18:47:15 -0300 [thread overview]
Message-ID: <20191217214728.2886-3-adhemerval.zanella@linaro.org> (raw)
In-Reply-To: <20191217214728.2886-1-adhemerval.zanella@linaro.org>
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(-)
diff --git a/sysdeps/unix/make-syscalls.sh b/sysdeps/unix/make-syscalls.sh
index fe24bbc78f..c07626677f 100644
--- a/sysdeps/unix/make-syscalls.sh
+++ b/sysdeps/unix/make-syscalls.sh
@@ -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
--
2.17.1
next prev parent reply other threads:[~2019-12-17 21:48 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-17 21:47 [PATCH v2 01/16] linux: Fix vDSO macros build with time64 interfaces Adhemerval Zanella
2019-12-17 21:47 ` [PATCH v2 02/16] x86: Make x32 use x86 time implementation Adhemerval Zanella
2020-01-02 12:07 ` Siddhesh Poyarekar
2019-12-17 21:47 ` Adhemerval Zanella [this message]
2020-01-02 12:07 ` [PATCH 03/16] Remove vDSO support from make-syscall.sh Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 04/16] linux: Update x86 vDSO symbols Adhemerval Zanella
2020-01-02 12:07 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 05/16] linux: Update mips " Adhemerval Zanella
2020-01-02 12:08 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 06/16] linux: Consolidate Linux gettimeofday Adhemerval Zanella
2019-12-18 8:46 ` Andreas Schwab
2019-12-18 14:50 ` Adhemerval Zanella
2020-01-02 12:07 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 07/16] linux: Consolidate time implementation Adhemerval Zanella
2020-01-02 12:51 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH v3 08/16] elf: Enable relro for static build Adhemerval Zanella
2020-01-02 12:07 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH v3 09/16] elf: Move vDSO setup to rtld (BZ#24967) Adhemerval Zanella
2020-01-02 12:55 ` Siddhesh Poyarekar
2020-01-02 13:00 ` Adhemerval Zanella
2020-01-07 16:13 ` [PATCH v3 09/16] elf: Move vDSO setup to rtld (BZ#24967) - regression found Lukasz Majewski
2020-01-07 19:40 ` Adhemerval Zanella
2019-12-17 21:47 ` [PATCH v2 10/16] linux: Add support for clock_gettime64 vDSO Adhemerval Zanella
2020-01-02 13:03 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 11/16] linux: Optimize fallback 32-bit clock_gettime Adhemerval Zanella
2019-12-18 8:53 ` Andreas Schwab
2019-12-18 14:58 ` Adhemerval Zanella
2020-01-02 13:07 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 12/16] linux: Enable vDSO clock_gettime64 for i386 Adhemerval Zanella
2020-01-02 13:08 ` Siddhesh Poyarekar
2020-01-02 13:08 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 13/16] linux: Enable vDSO clock_gettime64 for arm Adhemerval Zanella
2020-01-02 13:08 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 14/16] linux: Enable vDSO clock_gettime64 for mips Adhemerval Zanella
2019-12-18 15:33 ` Florian Weimer
2020-01-02 13:13 ` Siddhesh Poyarekar
2020-01-02 13:50 ` Adhemerval Zanella
2020-01-02 14:09 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH v2 15/16] linux: Add support for clock_getres64 vDSO Adhemerval Zanella
2020-01-02 13:15 ` Siddhesh Poyarekar
2019-12-17 21:47 ` [PATCH 16/16] linux: Optimize fallback 32-bit clock_getres Adhemerval Zanella
2019-12-18 8:56 ` Andreas Schwab
2019-12-18 14:58 ` Adhemerval Zanella
2019-12-18 15:02 ` Adhemerval Zanella
2020-01-02 13:16 ` Siddhesh Poyarekar
2020-01-02 12:07 ` [PATCH v2 01/16] linux: Fix vDSO macros build with time64 interfaces Siddhesh Poyarekar
2020-01-02 12:55 ` Adhemerval Zanella
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