linux-kernel - [PATCH 3/5] xen: move checks for e820 conflicts further up

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240807103338.22007-4-jgross@suse.com>
Date: Wed,  7 Aug 2024 12:33:34 +0200
From: Juergen Gross <jgross@...e.com>
To: linux-kernel@...r.kernel.org,
	x86@...nel.org
Cc: Juergen Gross <jgross@...e.com>,
	Boris Ostrovsky <boris.ostrovsky@...cle.com>,
	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	Borislav Petkov <bp@...en8.de>,
	Dave Hansen <dave.hansen@...ux.intel.com>,
	"H. Peter Anvin" <hpa@...or.com>,
	xen-devel@...ts.xenproject.org
Subject: [PATCH 3/5] xen: move checks for e820 conflicts further up

Move the checks for e820 memory map conflicts using the
xen_chk_is_e820_usable() helper further up in order to prepare
resolving some of the possible conflicts by doing some e820 map
modifications, which must happen before evaluating the RAM layout.

Signed-off-by: Juergen Gross <jgross@...e.com>
Marek Marczykowski-Górecki <marmarek@...isiblethingslab.com>
---
 arch/x86/xen/setup.c | 44 ++++++++++++++++++++++----------------------
 1 file changed, 22 insertions(+), 22 deletions(-)

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 96765180514b..dba68951ed6b 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -764,6 +764,28 @@ char * __init xen_memory_setup(void)
 	/* Make sure the Xen-supplied memory map is well-ordered. */
 	e820__update_table(&xen_e820_table);
 
+	/*
+	 * Check whether the kernel itself conflicts with the target E820 map.
+	 * Failing now is better than running into weird problems later due
+	 * to relocating (and even reusing) pages with kernel text or data.
+	 */
+	xen_chk_is_e820_usable(__pa_symbol(_text),
+			       __pa_symbol(_end) - __pa_symbol(_text),
+			       "kernel");
+
+	/*
+	 * Check for a conflict of the xen_start_info memory with the target
+	 * E820 map.
+	 */
+	xen_chk_is_e820_usable(__pa(xen_start_info), sizeof(*xen_start_info),
+			       "xen_start_info");
+
+	/*
+	 * Check for a conflict of the hypervisor supplied page tables with
+	 * the target E820 map.
+	 */
+	xen_pt_check_e820();
+
 	max_pages = xen_get_max_pages();
 
 	/* How many extra pages do we need due to remapping? */
@@ -836,28 +858,6 @@ char * __init xen_memory_setup(void)
 
 	e820__update_table(e820_table);
 
-	/*
-	 * Check whether the kernel itself conflicts with the target E820 map.
-	 * Failing now is better than running into weird problems later due
-	 * to relocating (and even reusing) pages with kernel text or data.
-	 */
-	xen_chk_is_e820_usable(__pa_symbol(_text),
-			       __pa_symbol(_end) - __pa_symbol(_text),
-			       "kernel");
-
-	/*
-	 * Check for a conflict of the xen_start_info memory with the target
-	 * E820 map.
-	 */
-	xen_chk_is_e820_usable(__pa(xen_start_info), sizeof(*xen_start_info),
-			       "xen_start_info");
-
-	/*
-	 * Check for a conflict of the hypervisor supplied page tables with
-	 * the target E820 map.
-	 */
-	xen_pt_check_e820();
-
 	xen_reserve_xen_mfnlist();
 
 	/* Check for a conflict of the initrd with the target E820 map. */
-- 
2.43.0