From 04fafd58b54a2e9c61527f2c0f65a46e2f17fd44 Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Tue, 23 Mar 2010 09:35:31 +0000 Subject: [PATCH] x86: s3: ensure CR4.MCE is enabled after mcheck_init() Changeset 21045: 7751288b1386 introduces a potential issue: CR4.MCE is enabled before mcheck_init() -- thought looks I don't meet with an actual issue with this, we'd better fix it. Signed-off-by: Dexuan Cui --- xen/arch/x86/acpi/power.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/xen/arch/x86/acpi/power.c b/xen/arch/x86/acpi/power.c index dfe35468ac..e6847b3e4f 100644 --- a/xen/arch/x86/acpi/power.c +++ b/xen/arch/x86/acpi/power.c @@ -147,6 +147,7 @@ static int enter_state(u32 state) { unsigned long flags; int error; + unsigned long cr4; if ( (state <= ACPI_STATE_S0) || (state > ACPI_S_STATES_MAX) ) return -EINVAL; @@ -201,13 +202,15 @@ static int enter_state(u32 state) } /* Restore CR4 and EFER from cached values. */ - write_cr4(read_cr4()); + cr4 = read_cr4(); + write_cr4(cr4 & ~X86_CR4_MCE); if ( cpu_has_efer ) write_efer(read_efer()); device_power_up(); mcheck_init(&boot_cpu_data); + write_cr4(cr4); printk(XENLOG_INFO "Finishing wakeup from ACPI S%d state.\n", state); -- 2.30.2