local-ldso-disable-hwcap

# DP: Allow hwcap's to be disabled with the existence of a file. This
# DP: makes it easier to do upgrades with optimized (hwcap) library
# DP: packages.
# DP: Author: Rewritten by Daniel Jacobowitz <dan@debian.org>
# DP: Upstream status: Debian-Specific
# DP: Status Details: This isn't going to be acceptable upstream, we
# DP:                 only need it because we support in-place upgrades.
# DP: Date: 2003-10-28, (Updated 2005-01-02 gotom, 2007-05-20 aurel32)

Gbp-Pq: Topic any
Gbp-Pq: Name local-ldso-disable-hwcap.diff

diff --git a/elf/dl-cache.c b/elf/dl-cache.c
index e9632da0b349b07acf38d5f92494f3d0858cf011..b32de3308de8a31dcb75cbe0f9aad357c9fe9b5a 100644 (file)
--- a/elf/dl-cache.c
+++ b/elf/dl-cache.c
@@ -25,6 +25,9 @@
 #include <stdint.h>
 #include <_itoa.h>
 #include <dl-hwcaps.h>
+#include <fcntl.h>
+#include <sysdep.h>
+#include <not-errno.h>
 
 #ifndef _DL_PLATFORMS_COUNT
 # define _DL_PLATFORMS_COUNT 0
@@ -248,6 +251,7 @@ _dl_load_cache_lookup (const char *name)
   if (cache_new != (void *) -1)
     {
       uint64_t platform;
+      int disable_hwcap = 0;
 
       /* This is where the strings start.  */
       cache_data = (const char *) cache_new;
@@ -261,6 +265,9 @@ _dl_load_cache_lookup (const char *name)
 
       uint64_t hwcap_mask = GET_HWCAP_MASK();
 
+      if (__access_noerrno ("/etc/ld.so.nohwcap", F_OK) == 0)
+       disable_hwcap = 1;
+
 #define _DL_HWCAP_TLS_MASK (1LL << 63)
       uint64_t hwcap_exclude = ~((GLRO(dl_hwcap) & hwcap_mask)
                                 | _DL_HWCAP_PLATFORM | _DL_HWCAP_TLS_MASK);
@@ -271,6 +278,8 @@ _dl_load_cache_lookup (const char *name)
        continue;                                                             \
       if (GLRO(dl_osversion) && lib->osversion > GLRO(dl_osversion))         \
        continue;                                                             \
+      if (disable_hwcap && lib->hwcap != 0)                                  \
+       continue;                                                             \
       if (_DL_PLATFORMS_COUNT                                                \
          && (lib->hwcap & _DL_HWCAP_PLATFORM) != 0                           \
          && (lib->hwcap & _DL_HWCAP_PLATFORM) != platform)                   \

diff --git a/elf/dl-hwcaps.c b/elf/dl-hwcaps.c
index ac50fd2c38d1f3cbb44cb1e23260789e0a3f3fcc..fd9d47a3d1266958f66b506eb4bb552e0d2dfa47 100644 (file)
--- a/elf/dl-hwcaps.c
+++ b/elf/dl-hwcaps.c
@@ -22,6 +22,9 @@
 #include <libintl.h>
 #include <unistd.h>
 #include <ldsodefs.h>
+#include <fcntl.h>
+#include <sysdep.h>
+#include <not-errno.h>
 
 #include <dl-procinfo.h>
 #include <dl-hwcaps.h>
@@ -44,6 +47,7 @@ _dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz,
   size_t cnt = platform != NULL;
   size_t n, m;
   size_t total;
+  struct r_strlenpair *temp;
   struct r_strlenpair *result;
   struct r_strlenpair *rp;
   char *cp;
@@ -113,8 +117,22 @@ _dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz,
   /* For TLS enabled builds always add 'tls'.  */
   ++cnt;
 
+  if (__access_noerrno ("/etc/ld.so.nohwcap", F_OK) == 0)
+    {
+      /* If hwcap is disabled, we only have the base directory to search.  */
+      result = (struct r_strlenpair *) malloc (sizeof (*result));
+      if (result == NULL)
+       goto no_memory;
+
+      result[0].str = (char *) result;  /* Does not really matter.  */
+      result[0].len = 0;
+
+      *sz = 1;
+      return result;
+    }
+
   /* Create temporary data structure to generate result table.  */
-  struct r_strlenpair temp[cnt];
+  temp = (struct r_strlenpair *) alloca (cnt * sizeof (*temp));
   m = 0;
 #ifdef NEED_DL_SYSINFO_DSO
   if (dsocaps != NULL)
@@ -199,8 +217,11 @@ _dl_important_hwcaps (const char *platform, size_t platform_len, size_t *sz,
   *sz = 1 << cnt;
   result = (struct r_strlenpair *) malloc (*sz * sizeof (*result) + total);
   if (result == NULL)
-    _dl_signal_error (ENOMEM, NULL, NULL,
-                     N_("cannot create capability list"));
+    {
+    no_memory:
+      _dl_signal_error (ENOMEM, NULL, NULL,
+                       N_("cannot create capability list"));
+    }
 
   if (cnt == 1)
     {