From 570c443352023691f4f7c9ed40199f18c746568c Mon Sep 17 00:00:00 2001 From: Stefan Liebler Date: Tue, 17 Jan 2017 08:54:58 +0100 Subject: S390: Fix FAIL in test string/tst-xbzero-opt [BZ #21006] On s390x this test failed with: FAIL: explicit clear/test: expected 0 got 1 In setup_explicit_clear, the buffer is filled with the test_pattern. On s390x the memcpy in prepare_test_buffer is done by loading r4 / r5 with the test_pattern and using store multiple instruction to store r4 / r5 to buf. If explicit_bzero is resolved in setup_explicit_clear, r4 / r5 is stored to stack by _dl_runtime_resolve and the call to memmem in count_test_patterns finds a hit of the test_pattern on the stack. This patch resolves all symbols at program startup by linking with -z now. This omits the call of _dl_runtime_resolve within setup_explicit_clear and the test passes. ChangeLog: [BZ #21006] * string/Makefile (LDFLAGS-tst-xbzero-opt): New variable. --- string/Makefile | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'string') diff --git a/string/Makefile b/string/Makefile index 7b3afa0..901c4d4 100644 --- a/string/Makefile +++ b/string/Makefile @@ -74,6 +74,14 @@ CFLAGS-stratcliff.c = -fno-builtin CFLAGS-test-ffs.c = -fno-builtin CFLAGS-tst-inlcall.c = -fno-builtin CFLAGS-tst-xbzero-opt.c = -O3 +# BZ 21006: Resolve all functions but at least explicit_bzero at startup. +# Otherwise the test fails on s390x as the memcpy in prepare_test_buffer is +# done by loading r4 / r5 with the test_pattern and using store multiple +# instruction to store r4 / r5 to buf. If explicit_bzero would be resolved in +# setup_explicit_clear, r4 / r5 would be stored to stack by _dl_runtime_resolve +# and the call to memmem in count_test_patterns will find a hit of the +# test_pattern on the stack. +LDFLAGS-tst-xbzero-opt = -z now # Called during TLS initialization. CFLAGS-memcpy.c = $(no-stack-protector) -- cgit v1.1