[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[PATCH 14/16] x86/shadow: "monitor table" is a HVM-only concept


  • To: "xen-devel@xxxxxxxxxxxxxxxxxxxx" <xen-devel@xxxxxxxxxxxxxxxxxxxx>
  • From: Jan Beulich <jbeulich@xxxxxxxx>
  • Date: Wed, 22 Mar 2023 10:37:12 +0100
  • Arc-authentication-results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=suse.com; dmarc=pass action=none header.from=suse.com; dkim=pass header.d=suse.com; arc=none
  • Arc-message-signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=PgsxcZsHQjbNHsFKcOrDGaTeJBLRhJa3sv6jEIQVDaY=; b=Uwl8RRsesj6Qairbj6d0oPaeuxxjd6rimp8Md+m1FJEPaaMUH/PKnLGFItGqA2rQVL/C6xhBEwA5PG0pm31S3BFp18OWomjarwOHKR1gtmWHKCo0dK3hsfhFBi17z5sjJHwhFH+l2cujoFM29qpy1RCtyJhNUNngvzTtN/E6oXxKNDmY78aZI6rg1d3Rh7wNZ129dykH4rpw2/P56m+Xgj3RGKSz0UhLhtrk+HzZ98OP6+okBj3eIYxwvTRUBDWJ0DpJMxIkSu59gIHzIqvdX0xijnbLED6XGDs6BN4uqXBTe8RaxaRxcJYuP36L2LtQWwm2Z6CDTTVSRZQ9SZAhWQ==
  • Arc-seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=XFvqM1KPxmtdbYXZqIDWhEjl+u3JlLZYGPxUL5a/FAe/RNe37xuwVCz6l0ynHNwSbWx+0yXfS29pdz+M9TMRpVMKRlBbzenxHKO+MD81HCsi0SmyEb23HTYwaQTtjUH1nhn9439XyruHe9ue+/9hFWyY7U9qBf5cEkuzvX81QswMHr5ELh29wNdBVGB6lDfiw260Pl3COJj3smsox0sGj00Bx5Ci50AGKUAv9s1hK05w9FqJzCBivWx68ielPWz4ARoko8CWsKhwojhFAhHMQ/fVBvfGAIDMOeKT7TSzhjujGCxtBNPCLU/GK6XfZy0BVRvyA1D9wjvpSuy/m+8Kkg==
  • Authentication-results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=suse.com;
  • Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>, Wei Liu <wl@xxxxxxx>, Roger Pau Monné <roger.pau@xxxxxxxxxx>, George Dunlap <george.dunlap@xxxxxxxxxx>, Tim Deegan <tim@xxxxxxx>
  • Delivery-date: Wed, 22 Mar 2023 09:37:18 +0000
  • List-id: Xen developer discussion <xen-devel.lists.xenproject.org>

It looks like in the combination of aff8bf94ce65 ('x86/shadow: only
4-level guest code needs building when !HVM') and 0b841314dace
('x86/shadow: sh_{make,destroy}_monitor_table() are "even more" HVM-
only') I didn't go quite far enough: SH_type_monitor_table is also
effectively unused when !HVM.

The assertion early in sh_destroy_shadow() can have the type dropped
altogether: it shouldn't make it here in the first place. Pages of
this type are freed directly from sh_destroy_monitor_table() only.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/mm/shadow/common.c
+++ b/xen/arch/x86/mm/shadow/common.c
@@ -1190,7 +1190,6 @@ void sh_destroy_shadow(struct domain *d,
     ASSERT(t == SH_type_fl1_32_shadow  ||
            t == SH_type_fl1_pae_shadow ||
            t == SH_type_fl1_64_shadow  ||
-           t == SH_type_monitor_table  ||
            (is_pv_32bit_domain(d) && t == SH_type_l4_64_shadow) ||
            (page_get_owner(mfn_to_page(backpointer(sp))) == d));
 
--- a/xen/arch/x86/mm/shadow/private.h
+++ b/xen/arch/x86/mm/shadow/private.h
@@ -205,8 +205,7 @@ extern void shadow_audit_tables(struct v
 #define SH_type_l4_64_shadow   6U /* shadowing a 64-bit L4 page */
 #define SH_type_max_shadow     6U
 #define SH_type_p2m_table      7U /* in use as the p2m table */
-#define SH_type_monitor_table  8U /* in use as a monitor table */
-#define SH_type_unused         9U
+#define SH_type_unused         8U
 #endif
 
 #ifndef CONFIG_PV32 /* Unused (but uglier to #ifdef above): */




 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.