From: Jeremy Linton <lintonrjeremy@gmail.com>
Date: Tue, 11 Dec 2018 18:27:29 +0000 (-0600)
Subject: lscpu: Add aarch32 detection on aarch64
X-Git-Tag: v2.34-rc1~182^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=32865bd5df59f14fd3fe6651acebde99b0691b5d;p=thirdparty%2Futil-linux.git

lscpu: Add aarch32 detection on aarch64

aarch32 support is an optional feature of ARMv8, as CPUs
which don't support aarch32 become more common, lets make
sure that lscpu can tell a user quickly if they are on a
machine that only supports 64-bit.

Signed-off-by: Jeremy Linton <lintonrjeremy@gmail.com>
---

diff --git a/sys-utils/lscpu.c b/sys-utils/lscpu.c
index 1ff9069f34..245be6e5ce 100644
--- a/sys-utils/lscpu.c
+++ b/sys-utils/lscpu.c
@@ -33,6 +33,7 @@
 #include <stdarg.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <sys/personality.h>
 
 #if (defined(__x86_64__) || defined(__i386__))
 # if !defined( __SANITIZE_ADDRESS__)
@@ -332,6 +333,19 @@ init_mode(struct lscpu_modifier *mod)
     defined(__s390x__) || defined(__s390__) || defined(__sparc_v9__)
 	m |= MODE_32BIT;
 #endif
+
+#if defined(__aarch64__)
+	{
+		/* personality() is the most reliable way (since 4.7)
+		 * to determine aarch32 support */
+		int pers = personality(PER_LINUX32);
+		if (pers != -1) {
+			personality(pers);
+			m |= MODE_32BIT;
+		}
+		m |= MODE_64BIT;
+	}
+#endif
 	return m;
 }