linux-kernel - [PATCH 7/7] xen/acpi/sleep: Register to the acpi_suspend

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 for Android: free password hash cracker in your pocket

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

Message-Id: <1321392671-9128-8-git-send-email-konrad.wilk@oracle.com>
Date:	Tue, 15 Nov 2011 16:31:11 -0500
From:	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
To:	linux-kernel@...r.kernel.org, rjw@...k.pl, tglx@...utronix.de,
	x86@...nel.org, hpa@...or.com, len.brown@...el.com,
	joseph.cihula@...el.com, linux-pm@...ts.linux-foundation.org,
	tboot-devel@...ts.sourceforge.net, linux-acpi@...r.kernel.org,
	liang.tang@...cle.com
Cc:	xen-devel@...ts.xensource.com,
	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
Subject: [PATCH 7/7] xen/acpi/sleep: Register to the acpi_suspend_lowlevel a callback.

We piggyback on "x86/acpi: Provide registration for acpi_suspend_lowlevel."
to register a Xen version of the callback. The callback does not
do anything special - except it omits the x86_acpi_suspend_lowlevel.
It does that b/c during suspend it tries to save cr8 values (which
the hypervisor does not support), and then on resume path the
cr3, cr8, idt, and gdt are all resumed which clashes with what
the hypervisor has set up for the guest.

Signed-off-by: Liang Tang <liang.tang@...cle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
---
 include/xen/acpi.h |   17 ++++++++++++++++-
 1 files changed, 16 insertions(+), 1 deletions(-)

diff --git a/include/xen/acpi.h b/include/xen/acpi.h
index 69a6890..832b5e5 100644
--- a/include/xen/acpi.h
+++ b/include/xen/acpi.h
@@ -44,11 +44,26 @@
 acpi_status xen_acpi_notify_hypervisor_state(u8 sleep_state,
 				     u32 pm1a_cnt, u32 pm1b_cnd);
 
+static inline int xen_acpi_suspend_lowlevel(void)
+{
+	/*
+	* Xen will save and restore CPU context, so
+	* we can skip that and just go straight to
+	* the suspend.
+	*/
+	acpi_enter_sleep_state(ACPI_STATE_S3);
+	return 0;
+}
+
+
 static inline void xen_acpi_sleep_register(void)
 {
-	if (xen_initial_domain())
+	if (xen_initial_domain()){
 		acpi_os_prepare_sleep_register(
 			&xen_acpi_notify_hypervisor_state);
+
+		acpi_suspend_lowlevel = xen_acpi_suspend_lowlevel;
+	}
 }
 #else
 static inline void xen_acpi_sleep_register(void)
-- 
1.7.7.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/