[v2,5/6] x86: Add x86-64-vN check to early startup

Message ID 703f911ba1d0d946e4978830e5d3161674bfc77c.1642179009.git.fweimer@redhat.com
State New
Headers show
Series
  • Reliable CPU compatibility diagnostics in ld.so
Related show

Commit Message

Sunil K Pandey via Libc-alpha Jan. 14, 2022, 4:53 p.m.
This ISA level covers the glibc build itself.  <dl-hwcap-check.h>
cannot be used because this check (by design) happens before
DL_PLATFORM_INIT and the x86 CPU flags initialization.
---
v2: Reflect renamed Makefile variable.
 sysdeps/x86/Makefile              |  1 +
 sysdeps/x86/dl-get-cpu-features.c | 31 ++++++++++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 1 deletion(-)

-- 
2.34.1

Comments

Sunil K Pandey via Libc-alpha Jan. 14, 2022, 6:40 p.m. | #1
On Fri, Jan 14, 2022 at 8:53 AM Florian Weimer <fweimer@redhat.com> wrote:
>

> This ISA level covers the glibc build itself.  <dl-hwcap-check.h>

> cannot be used because this check (by design) happens before

> DL_PLATFORM_INIT and the x86 CPU flags initialization.

> ---

> v2: Reflect renamed Makefile variable.

>  sysdeps/x86/Makefile              |  1 +

>  sysdeps/x86/dl-get-cpu-features.c | 31 ++++++++++++++++++++++++++++++-

>  2 files changed, 31 insertions(+), 1 deletion(-)

>

> diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile

> index 402986ff68..6cf708335c 100644

> --- a/sysdeps/x86/Makefile

> +++ b/sysdeps/x86/Makefile

> @@ -7,6 +7,7 @@ sysdep_routines += get-cpuid-feature-leaf

>  sysdep-dl-routines += dl-get-cpu-features

>  sysdep_headers += sys/platform/x86.h bits/platform/x86.h

>

> +CFLAGS-dl-get-cpu-features.os += $(rtld-early-cflags)

>  CFLAGS-get-cpuid-feature-leaf.o += $(no-stack-protector)

>

>  tests += tst-get-cpu-features tst-get-cpu-features-static \

> diff --git a/sysdeps/x86/dl-get-cpu-features.c b/sysdeps/x86/dl-get-cpu-features.c

> index 6339c9df4e..4ec0e5d2af 100644

> --- a/sysdeps/x86/dl-get-cpu-features.c

> +++ b/sysdeps/x86/dl-get-cpu-features.c

> @@ -20,6 +20,7 @@

>

>  #ifdef SHARED

>  # include <cpu-features.c>

> +# include <gcc-macros.h>

>

>  /* NB: Normally, DL_PLATFORM_INIT calls init_cpu_features to initialize

>     CPU features in dynamic executable.  But when loading ld.so inside of

> @@ -36,7 +37,35 @@ _dl_x86_init_cpu_features (void)

>  {

>    struct cpu_features *cpu_features = __get_cpu_features ();

>    if (cpu_features->basic.kind == arch_kind_unknown)

> -    init_cpu_features (cpu_features);

> +    {

> +      init_cpu_features (cpu_features);

> +

> +# if IS_IN (rtld)

> +      /* See isa-level.c.  */

> +#  if defined GCCMACRO__GCC_HAVE_SYNC_COMPARE_AND_SWAP_16              \

> +  && defined HAVE_X86_LAHF_SAHF && defined GCCMACRO__POPCNT__          \

> +  && defined GCCMACRO__SSE3__ && defined GCCMACRO__SSSE3__             \

> +  && defined GCCMACRO__SSE4_1__ && defined GCCMACRO__SSE4_2__

> +      if (!(cpu_features->isa_1 & GNU_PROPERTY_X86_ISA_1_V2))

> +       _dl_fatal_printf ("\

> +Fatal glibc error: CPU does not support x86-64-v%d\n", 2);

> +#   if defined GCCMACRO__AVX__ && defined GCCMACRO__AVX2__ \

> +  && defined GCCMACRO__F16C__ && defined GCCMACRO__FMA__   \

> +  && defined GCCMACRO__LZCNT__ && defined HAVE_X86_MOVBE

> +      if (!(cpu_features->isa_1 & GNU_PROPERTY_X86_ISA_1_V3))

> +       _dl_fatal_printf ("\

> +Fatal glibc error: CPU does not support x86-64-v%d\n", 3);

> +#    if defined GCCMACRO__AVX512F__ && defined GCCMACRO__AVX512BW__ \

> +     && defined GCCMACRO__AVX512CD__ && defined GCCMACRO__AVX512DQ__ \

> +     && defined GCCMACRO__AVX512VL__

> +      if (!(cpu_features->isa_1 & GNU_PROPERTY_X86_ISA_1_V4))

> +       _dl_fatal_printf ("\

> +Fatal glibc error: CPU does not support x86-64-v%d\n", 4);

> +#    endif /* ISA level 4 */

> +#   endif /* ISA level 3 */

> +#  endif /* ISA level 2 */

> +# endif /* IS_IN (rtld) */

> +    }

>  }

>

>  __ifunc (__x86_cpu_features, __x86_cpu_features, NULL, void,

> --

> 2.34.1

>

>


LGTM.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>


Thanks.

-- 
H.J.

Patch

diff --git a/sysdeps/x86/Makefile b/sysdeps/x86/Makefile
index 402986ff68..6cf708335c 100644
--- a/sysdeps/x86/Makefile
+++ b/sysdeps/x86/Makefile
@@ -7,6 +7,7 @@  sysdep_routines += get-cpuid-feature-leaf
 sysdep-dl-routines += dl-get-cpu-features
 sysdep_headers += sys/platform/x86.h bits/platform/x86.h
 
+CFLAGS-dl-get-cpu-features.os += $(rtld-early-cflags)
 CFLAGS-get-cpuid-feature-leaf.o += $(no-stack-protector)
 
 tests += tst-get-cpu-features tst-get-cpu-features-static \
diff --git a/sysdeps/x86/dl-get-cpu-features.c b/sysdeps/x86/dl-get-cpu-features.c
index 6339c9df4e..4ec0e5d2af 100644
--- a/sysdeps/x86/dl-get-cpu-features.c
+++ b/sysdeps/x86/dl-get-cpu-features.c
@@ -20,6 +20,7 @@ 
 
 #ifdef SHARED
 # include <cpu-features.c>
+# include <gcc-macros.h>
 
 /* NB: Normally, DL_PLATFORM_INIT calls init_cpu_features to initialize
    CPU features in dynamic executable.  But when loading ld.so inside of
@@ -36,7 +37,35 @@  _dl_x86_init_cpu_features (void)
 {
   struct cpu_features *cpu_features = __get_cpu_features ();
   if (cpu_features->basic.kind == arch_kind_unknown)
-    init_cpu_features (cpu_features);
+    {
+      init_cpu_features (cpu_features);
+
+# if IS_IN (rtld)
+      /* See isa-level.c.  */
+#  if defined GCCMACRO__GCC_HAVE_SYNC_COMPARE_AND_SWAP_16		\
+  && defined HAVE_X86_LAHF_SAHF && defined GCCMACRO__POPCNT__		\
+  && defined GCCMACRO__SSE3__ && defined GCCMACRO__SSSE3__		\
+  && defined GCCMACRO__SSE4_1__ && defined GCCMACRO__SSE4_2__
+      if (!(cpu_features->isa_1 & GNU_PROPERTY_X86_ISA_1_V2))
+	_dl_fatal_printf ("\
+Fatal glibc error: CPU does not support x86-64-v%d\n", 2);
+#   if defined GCCMACRO__AVX__ && defined GCCMACRO__AVX2__ \
+  && defined GCCMACRO__F16C__ && defined GCCMACRO__FMA__   \
+  && defined GCCMACRO__LZCNT__ && defined HAVE_X86_MOVBE
+      if (!(cpu_features->isa_1 & GNU_PROPERTY_X86_ISA_1_V3))
+	_dl_fatal_printf ("\
+Fatal glibc error: CPU does not support x86-64-v%d\n", 3);
+#    if defined GCCMACRO__AVX512F__ && defined GCCMACRO__AVX512BW__ \
+     && defined GCCMACRO__AVX512CD__ && defined GCCMACRO__AVX512DQ__ \
+     && defined GCCMACRO__AVX512VL__
+      if (!(cpu_features->isa_1 & GNU_PROPERTY_X86_ISA_1_V4))
+	_dl_fatal_printf ("\
+Fatal glibc error: CPU does not support x86-64-v%d\n", 4);
+#    endif /* ISA level 4 */
+#   endif /* ISA level 3 */
+#  endif /* ISA level 2 */
+# endif /* IS_IN (rtld) */
+    }
 }
 
 __ifunc (__x86_cpu_features, __x86_cpu_features, NULL, void,