From 55736aa8c17f762b15e9bcd7b3f68f8680b7cb33 Mon Sep 17 00:00:00 2001
From: Egbert Eich <eich@suse.de>
Date: Fri, 21 Jan 2005 14:25:26 +0000
Subject: [PATCH] Alan Cox requested that we check the kernel version before we
 use kernel     VGA font save/restore as the required features have been added
 to Linux     2.6.11 (Bugzilla #2277).

---
 hw/xfree86/os-support/linux/lnx_font.c | 29 ++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/hw/xfree86/os-support/linux/lnx_font.c b/hw/xfree86/os-support/linux/lnx_font.c
index 10ea433c5..05bf7da67 100644
--- a/hw/xfree86/os-support/linux/lnx_font.c
+++ b/hw/xfree86/os-support/linux/lnx_font.c
@@ -112,10 +112,16 @@ getfont(int *width, int *height,
 
 }
 
+#define VERSION_LEN 31
+
 Bool
 lnx_savefont(void)
 {
     unsigned char *fontdata;
+#if CHECK_OS_VERSION
+    char kernel_version[VERSION_LEN + 1];
+    int k_major, k_minor, k_release;
+#endif
     int size;
     int fd;
     int width = 32, height = 32, charcount = 2048;
@@ -123,6 +129,29 @@ lnx_savefont(void)
 #ifdef DEBUG
     ErrorF("SAVE font\n");
 #endif
+
+#if CHECK_OS_VERSION
+    /* Check if the kernel has full support for this */
+    if ((fd = open ("/proc/sys/kernel/osrelease",O_RDONLY)) == -1) {
+	close (fd);
+	return TRUE;
+    }
+    size = read(fd, kernel_version, VERSION_LEN);
+    close (fd);
+
+    if (size < 0)
+	return TRUE;
+
+    size = sscanf(kernel_version, "%d.%d.%d",&k_major,&k_minor,&k_release);
+    if (size < 3 
+	|| (k_major < 2) 
+	|| ((k_major == 2) 
+	    && ((k_minor < 6) 
+		|| ( k_minor == 6 
+		     && k_release < 11))))
+	return TRUE;
+#endif
+							    
     /* if we are in fbdev mode we don't bother saving fonts */
     if ((fd = open ("/dev/fb0",O_RDWR)) != -1) {
 	close (fd);