[PATCH] Fix output of LD_SHOW_AUXV=1.

[Stefan Liebler <stli@linux.ibm.com>]

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Hi,

starting with commit 1616d034b61622836d3a36af53dcfca7624c844e
the output was corrupted on some platforms as _dl_procinfo
was called for every auxv entry and on some architectures like s390
all entries were represented as "AT_HWCAP".

This patch fixes the condition which determines if _dl_procinfo
is called and adjusts _dl_procinfo implementations which assumed
that they are only called for AT_HWCAP or AT_HWCAP2.

A further question is if we should always call _dl_procinfo without a 
condition and let it decide if it is able to print an entry or if it 
should be printed with help of the auxvars list?

Okay to commit?
Once it is committed I would also backport it to glibc 2.29 release branch.

Bye,
Stefan

ChangeLog:

	* elf/dl-sysdep.c (_dl_show_auxv): Fix condition if _dl_procinfo
	is called.
	* sysdeps/unix/sysv/linux/s390/dl-procinfo.h (_dl_procinfo):
	Ignore types other than AT_HWCAP.
	* sysdeps/sparc/dl-procinfo.h (_dl_procinfo): Likewise.
	* sysdeps/unix/sysv/linux/i386/dl-procinfo.h (_dl_procinfo):
	Likewise.

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commit 5bbde0719d7c5fa58b0140d6fb1c6fa31a372772
Author: Stefan Liebler <stli@linux.ibm.com>
Date:   Fri Mar 8 11:18:53 2019 +0100

    Fix output of LD_SHOW_AUXV=1.
    
    Starting with commit 1616d034b61622836d3a36af53dcfca7624c844e
    the output was corrupted on some platforms as _dl_procinfo
    was called for every auxv entry and on some architectures like s390
    all entries were represented as "AT_HWCAP".
    
    This patch fixes the condition which determines if _dl_procinfo
    is called and adjusts _dl_procinfo implementations which assumed
    that they are only called for AT_HWCAP or AT_HWCAP2.
    
    ChangeLog:
    
            * elf/dl-sysdep.c (_dl_show_auxv): Fix condition if _dl_procinfo
            is called.
            * sysdeps/unix/sysv/linux/s390/dl-procinfo.h (_dl_procinfo):
            Ignore types other than AT_HWCAP.
            * sysdeps/sparc/dl-procinfo.h (_dl_procinfo): Likewise.
            * sysdeps/unix/sysv/linux/i386/dl-procinfo.h (_dl_procinfo): Likewise.

diff --git a/elf/dl-sysdep.c b/elf/dl-sysdep.c
index 5f6c679a3f..1588555651 100644
--- a/elf/dl-sysdep.c
+++ b/elf/dl-sysdep.c
@@ -329,8 +329,10 @@ _dl_show_auxv (void)
       assert (AT_IGNORE == 1);
 
       if (av->a_type == AT_HWCAP || av->a_type == AT_HWCAP2
-	  || AT_L1I_CACHEGEOMETRY || AT_L1D_CACHEGEOMETRY
-	  || AT_L2_CACHEGEOMETRY || AT_L3_CACHEGEOMETRY)
+	  || av->a_type == AT_L1I_CACHEGEOMETRY
+	  || av->a_type == AT_L1D_CACHEGEOMETRY
+	  || av->a_type == AT_L2_CACHEGEOMETRY
+	  || av->a_type == AT_L3_CACHEGEOMETRY)
 	{
 	  /* These are handled in a special way per platform.  */
 	  if (_dl_procinfo (av->a_type, av->a_un.a_val) == 0)
diff --git a/sysdeps/sparc/dl-procinfo.h b/sysdeps/sparc/dl-procinfo.h
index 282b8c5117..cc2687e99b 100644
--- a/sysdeps/sparc/dl-procinfo.h
+++ b/sysdeps/sparc/dl-procinfo.h
@@ -32,7 +32,7 @@ _dl_procinfo (unsigned int type, unsigned long int word)
   int i;
 
   /* Fallback to unknown output mechanism.  */
-  if (type == AT_HWCAP2)
+  if (type != AT_HWCAP)
     return -1;
 
   _dl_printf ("AT_HWCAP:   ");
diff --git a/sysdeps/unix/sysv/linux/i386/dl-procinfo.h b/sysdeps/unix/sysv/linux/i386/dl-procinfo.h
index 22b43431bc..3aef14c6c1 100644
--- a/sysdeps/unix/sysv/linux/i386/dl-procinfo.h
+++ b/sysdeps/unix/sysv/linux/i386/dl-procinfo.h
@@ -31,7 +31,7 @@ _dl_procinfo (unsigned int type, unsigned long int word)
   int i;
 
   /* Fallback to unknown output mechanism.  */
-  if (type == AT_HWCAP2)
+  if (type != AT_HWCAP)
     return -1;
 
   _dl_printf ("AT_HWCAP:   ");
diff --git a/sysdeps/unix/sysv/linux/s390/dl-procinfo.h b/sysdeps/unix/sysv/linux/s390/dl-procinfo.h
index 19329a335b..16739fd6cd 100644
--- a/sysdeps/unix/sysv/linux/s390/dl-procinfo.h
+++ b/sysdeps/unix/sysv/linux/s390/dl-procinfo.h
@@ -33,7 +33,7 @@ _dl_procinfo (unsigned int type, unsigned long int word)
   int i;
 
   /* Fallback to unknown output mechanism.  */
-  if (type == AT_HWCAP2)
+  if (type != AT_HWCAP)
     return -1;
 
   _dl_printf ("AT_HWCAP:   ");