diff --git a/configure b/configure
index bed9eab3673..244b66545ef 100755
--- a/configure
+++ b/configure
@@ -19643,6 +19643,32 @@ _ACEOF
 fi
 
 
+ac_fn_c_check_member "$LINENO" "struct sysinfo" "totalram" "ac_cv_member_struct_sysinfo_totalram" "#ifdef HAVE_SYS_SYSINFO_H
+# include <sys/sysinfo.h>
+#endif
+"
+if test "x$ac_cv_member_struct_sysinfo_totalram" = xyes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_STRUCT_SYSINFO_TOTALRAM 1
+_ACEOF
+
+
+fi
+ac_fn_c_check_member "$LINENO" "struct sysinfo" "mem_unit" "ac_cv_member_struct_sysinfo_mem_unit" "#ifdef HAVE_SYS_SYSINFO_H
+# include <sys/sysinfo.h>
+#endif
+"
+if test "x$ac_cv_member_struct_sysinfo_mem_unit" = xyes; then :
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_STRUCT_SYSINFO_MEM_UNIT 1
+_ACEOF
+
+
+fi
+
+
 ac_save_LIBS="$LIBS"
 LIBS="$LIBS -lm"
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for isfinite" >&5
diff --git a/configure.ac b/configure.ac
index 29ff38f169b..47d0471169a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2658,6 +2658,12 @@ AC_CHECK_MEMBERS([struct ifreq.ifr_hwaddr],,,
 # include <net/if.h>
 #endif])
 
+dnl Check for struct sysinfo members totalram and mem_unit
+AC_CHECK_MEMBERS([struct sysinfo.totalram, struct sysinfo.mem_unit],,,
+[#ifdef HAVE_SYS_SYSINFO_H
+# include <sys/sysinfo.h>
+#endif])
+
 dnl Check for isfinite
 ac_save_LIBS="$LIBS"
 LIBS="$LIBS -lm"
diff --git a/dlls/ntdll/unix/virtual.c b/dlls/ntdll/unix/virtual.c
index 9b1ca761e9b..a2fea588834 100644
--- a/dlls/ntdll/unix/virtual.c
+++ b/dlls/ntdll/unix/virtual.c
@@ -43,6 +43,9 @@
 #ifdef HAVE_SYS_SYSINFO_H
 # include <sys/sysinfo.h>
 #endif
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
 #ifdef HAVE_VALGRIND_VALGRIND_H
 # include <valgrind/valgrind.h>
 #endif
@@ -2481,22 +2484,26 @@ ULONG_PTR get_system_affinity_mask(void)
  */
 void virtual_get_system_info( SYSTEM_BASIC_INFORMATION *info )
 {
-#ifdef HAVE_SYSINFO
+#if defined(HAVE_STRUCT_SYSINFO_TOTALRAM) && defined(HAVE_STRUCT_SYSINFO_MEM_UNIT)
     struct sysinfo sinfo;
+
+    if (!sysinfo(&sinfo))
+    {
+        ULONG64 total = (ULONG64)sinfo.totalram * sinfo.mem_unit;
+        info->MmHighestPhysicalPage = max(1, total / page_size);
+    }
+#elif defined(_SC_PHYS_PAGES)
+    LONG64 phys_pages = sysconf( _SC_PHYS_PAGES );
+
+    info->MmHighestPhysicalPage = max(1, phys_pages);
+#else
+    info->MmHighestPhysicalPage = 0x7fffffff / page_size;
 #endif
 
     info->unknown                 = 0;
     info->KeMaximumIncrement      = 0;  /* FIXME */
     info->PageSize                = page_size;
     info->MmLowestPhysicalPage    = 1;
-    info->MmHighestPhysicalPage   = 0x7fffffff / page_size;
-#ifdef HAVE_SYSINFO
-    if (!sysinfo(&sinfo))
-    {
-        ULONG64 total = (ULONG64)sinfo.totalram * sinfo.mem_unit;
-        info->MmHighestPhysicalPage = max(1, total / page_size);
-    }
-#endif
     info->MmNumberOfPhysicalPages = info->MmHighestPhysicalPage - info->MmLowestPhysicalPage;
     info->AllocationGranularity   = granularity_mask + 1;
     info->LowestUserAddress       = (void *)0x10000;
diff --git a/include/config.h.in b/include/config.h.in
index 4d479a6cb3d..fc9305418c6 100644
--- a/include/config.h.in
+++ b/include/config.h.in
@@ -950,6 +950,12 @@
 /* Define to 1 if `__st_birthtime' is a member of `struct stat'. */
 #undef HAVE_STRUCT_STAT___ST_BIRTHTIME
 
+/* Define to 1 if `mem_unit' is a member of `struct sysinfo'. */
+#undef HAVE_STRUCT_SYSINFO_MEM_UNIT
+
+/* Define to 1 if `totalram' is a member of `struct sysinfo'. */
+#undef HAVE_STRUCT_SYSINFO_TOTALRAM
+
 /* Define to 1 if `tcps_connattempt' is a member of `struct tcpstat'. */
 #undef HAVE_STRUCT_TCPSTAT_TCPS_CONNATTEMPT