From: Alexander van Heukelum <heukelum@mailshack.com>
Date: Tue, 4 Mar 2008 19:12:28 +0000 (+0100)
Subject: x86: reserve end-of-conventional-memory to 1MB, 64-bit, use paravirt_enabled
X-Git-Tag: firefly_0821_release~21631^2~488
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=ecd94c0809eb0ff50b628fa061c531a6fbf2fbbc;p=firefly-linux-kernel-4.4.55.git

x86: reserve end-of-conventional-memory to 1MB, 64-bit, use paravirt_enabled

Jeremy Fitzhardinge pointed out that looking at the boot_params
struct to determine if the system is running in a paravirtual
environment is not reliable for the Xen case, currently. He also
points out that there already exists a function to determine if
the system is running in a paravirtual environment. So let's use
that instead. This gets rid of the preprocessor test too.

Signed-off-by: Alexander van Heukelum <heukelum@fastmail.fm>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---

diff --git a/arch/x86/kernel/head64.c b/arch/x86/kernel/head64.c
index 269a6b481fe6..48be76cda93b 100644
--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -72,12 +72,8 @@ static void __init reserve_ebda_region(void)
 	/* that area is absent. We'll just have to assume */
 	/* that the paravirt case can handle memory setup */
 	/* correctly, without our help. */
-#ifdef CONFIG_PARAVIRT
-	if ((boot_params.hdr.version >= 0x207) &&
-			(boot_params.hdr.hardware_subarch != 0)) {
+	if (paravirt_enabled())
 		return;
-	}
-#endif
 
 	/* end of low (conventional) memory */
 	lowmem = *(unsigned short *)__va(BIOS_LOWMEM_KILOBYTES);