From: caiyinyu <caiyinyu@loongson.cn>
To: libc-alpha@sourceware.org
Cc: adhemerval.zanella@linaro.org, hjl.tools@gmail.com,
carlos@redhat.com, caiyinyu <caiyinyu@loongson.cn>
Subject: [PATCH] x86: Fix bug about glibc.cpu.hwcaps.
Date: Wed, 1 Mar 2023 11:22:38 +0800 [thread overview]
Message-ID: <20230301032238.566874-1-caiyinyu@loongson.cn> (raw)
1. export GLIBC_TUNABLES=glibc.cpu.hwcaps=-AVX512
2. Add _dl_printf("p -- %s\n", p); just before switch(nl) in
sysdeps/x86/cpu-tunables.c
3. compiled and run ./testrun.sh /usr/bin/ls
you will get:
p -- -AVX512
p -- LC_ADDRESS=en_US.UTF-8
p -- LC_NUMERIC=C
...
The function, TUNABLE_CALLBACK (set_hwcaps)
(tunable_val_t *valp), checks far more than it should and it
should stop at end of "-AVX512".
---
sysdeps/x86/cpu-tunables.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/sysdeps/x86/cpu-tunables.c b/sysdeps/x86/cpu-tunables.c
index d3e1367bda..772fb0c4c2 100644
--- a/sysdeps/x86/cpu-tunables.c
+++ b/sysdeps/x86/cpu-tunables.c
@@ -107,13 +107,13 @@ TUNABLE_CALLBACK (set_hwcaps) (tunable_val_t *valp)
NOTE: the IFUNC selection may change over time. Please check all
multiarch implementations when experimenting. */
- const char *p = valp->strval;
+ const char *p = valp->strval, *c;
struct cpu_features *cpu_features = &GLRO(dl_x86_cpu_features);
size_t len;
do
{
- const char *c, *n;
+ const char *n;
bool disable;
size_t nl;
@@ -283,7 +283,7 @@ TUNABLE_CALLBACK (set_hwcaps) (tunable_val_t *valp)
}
p += len + 1;
}
- while (*p != '\0');
+ while (*c != '\0');
}
# if CET_ENABLED
--
2.31.1
next reply other threads:[~2023-03-01 3:22 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-03-01 3:22 caiyinyu [this message]
2023-03-01 4:19 ` Noah Goldstein
2023-03-01 9:10 ` caiyinyu
2023-03-01 16:42 ` Noah Goldstein
2023-03-01 17:33 ` H.J. Lu
2023-03-02 2:37 ` caiyinyu
2023-03-02 2:33 caiyinyu
2023-03-02 4:22 ` H.J. Lu
2023-03-07 12:45 ` caiyinyu
2023-03-07 13:02 ` Xi Ruoyao
2023-03-07 13:18 ` caiyinyu
2023-03-07 17:23 ` Noah Goldstein
2023-03-08 7:16 ` caiyinyu
2023-03-08 16:56 ` Noah Goldstein
2023-03-09 1:26 ` caiyinyu
2023-03-09 3:25 ` Xi Ruoyao
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