Re: [PATCH] Revert "x86_64: Suppress false positive valgrind error"

["H.J. Lu" <hjl.tools@gmail.com>]

On Sat, Apr 13, 2024 at 7:49 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> This reverts commit a1735e0aa858f0c8b15e5ee9975bff4279423680.
>
> The test failure is a real valgrind bug that needs to be fixed before
> valgrind is usable with a glibc that has been built with
> CC="gcc -march=x86-64-v3".  The valgrind fix addresses the observed
> test failure as well.
>
> Upstream bug: <https://bugs.kde.org/show_bug.cgi?id=485487>
>
> Tested on x86_64-linux-gnu with and without CC="gcc -march=x86-64-v3".
> The elf/tst-valgrind-smoke tests again fails with an unpatched valgrind,
> and the proposed upstream patch fixes it.  (Apparently, valgrind
> matches on soname, and not the file name, which is ld.so in the test.)

Please clarify that your patch fixes the glibc valgrind test by not using
strcmp-avx2.S in the valgrind test.

> ---
>  elf/Makefile                           |  3 +--
>  elf/tst-valgrind-smoke.sh              |  5 ++---
>  sysdeps/x86_64/Makefile                |  7 -------
>  sysdeps/x86_64/tst-valgrind-smoke.supp | 17 -----------------
>  4 files changed, 3 insertions(+), 29 deletions(-)
>
> diff --git a/elf/Makefile b/elf/Makefile
> index 6dad11bcfb..fb3c3c4dff 100644
> --- a/elf/Makefile
> +++ b/elf/Makefile
> @@ -618,8 +618,7 @@ tests-special += $(objpfx)tst-valgrind-smoke.out
>  endif
>  $(objpfx)tst-valgrind-smoke.out: tst-valgrind-smoke.sh $(objpfx)ld.so $(objpfx)valgrind-test
>         $(SHELL) $< $(objpfx)ld.so  $(rtlddir)/$(rtld-installed-name) '$(test-wrapper-env)' \
> -               '$(run-program-env)' '$(rpath-link)' $(objpfx)valgrind-test \
> -               '$(valgrind-suppressions-tst-valgrind-smoke)' > $@; $(evaluate-test)
> +               '$(run-program-env)' '$(rpath-link)' $(objpfx)valgrind-test > $@; $(evaluate-test)
>
>  ifeq ($(run-built-tests),yes)
>  tests-special += $(objpfx)tst-rtld-does-not-exist.out
> diff --git a/elf/tst-valgrind-smoke.sh b/elf/tst-valgrind-smoke.sh
> index 7d0ceac6b1..e33b2fa1d7 100644
> --- a/elf/tst-valgrind-smoke.sh
> +++ b/elf/tst-valgrind-smoke.sh
> @@ -25,7 +25,6 @@ test_wrapper_env="$3"
>  run_program_env="$4"
>  library_path="$5"
>  test_prog="$6"
> -valgrind_suppressions="$7"
>
>  # Test whether valgrind is available in the test
>  # environment.  If not, skip the test.
> @@ -35,7 +34,7 @@ ${test_wrapper_env} ${run_program_env} \
>  # Test valgrind works with the system ld.so in the test environment
>  /bin/sh -c \
>    "${test_wrapper_env} ${run_program_env} \
> -   valgrind -q --error-exitcode=1 ${valgrind_suppressions} \
> +   valgrind -q --error-exitcode=1 \
>       ${system_rtld} /bin/echo ${system_rtld}" || exit 77
>
>  # Finally the actual test inside the test environment,
> @@ -43,5 +42,5 @@ ${test_wrapper_env} ${run_program_env} \
>  # the smoke test under valgrind.
>  /bin/sh -c \
>    "${test_wrapper_env} ${run_program_env} \
> -   valgrind -q --error-exitcode=1 ${valgrind_suppressions} \
> +   valgrind -q --error-exitcode=1 \
>       ${rtld} --library-path ${library_path} ${test_prog} ${rtld}"
> diff --git a/sysdeps/x86_64/Makefile b/sysdeps/x86_64/Makefile
> index 39048b12e0..ce949dba27 100644
> --- a/sysdeps/x86_64/Makefile
> +++ b/sysdeps/x86_64/Makefile
> @@ -211,14 +211,7 @@ tst-plt-rewrite2-ENV = GLIBC_TUNABLES=glibc.cpu.plt_rewrite=2
>  $(objpfx)tst-plt-rewrite2: $(objpfx)tst-plt-rewritemod2.so
>  endif
>
> -# Check if ISA level is 3 or above.
> -ifneq (,$(filter $(have-x86-isa-level),$(x86-isa-level-3-or-above)))
> -valgrind-suppressions-tst-valgrind-smoke = \
> -  --suppressions=$(..)sysdeps/x86_64/tst-valgrind-smoke.supp
> -endif
> -
>  test-internal-extras += tst-gnu2-tls2mod1
> -
>  endif # $(subdir) == elf
>
>  ifeq ($(subdir),csu)
> diff --git a/sysdeps/x86_64/tst-valgrind-smoke.supp b/sysdeps/x86_64/tst-valgrind-smoke.supp
> deleted file mode 100644
> index 533c2deaff..0000000000
> --- a/sysdeps/x86_64/tst-valgrind-smoke.supp
> +++ /dev/null
> @@ -1,17 +0,0 @@
> -{
> -   False positive at strcmp-avx2.S:462
> -   Memcheck:Cond
> -   fun:strcmp
> -   fun:_dl_name_match_p
> -   fun:_dl_map_object
> -   fun:map_doit
> -   fun:_dl_catch_exception
> -   fun:_dl_catch_error
> -   fun:do_preload
> -   fun:handle_preload_list
> -   fun:dl_main
> -   fun:_dl_sysdep_start
> -   fun:_dl_start_final
> -   fun:_dl_start
> -   obj:*/elf/ld.so
> -}
>
> base-commit: ae7468a7b0bcf22e9cd5fcae42bb9e4f65de83ee
>


-- 
H.J.