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Date: Sun, 15 Feb 2015 17:11:41 +0200
From: Konstantin Belousov <kostikbel@gmail.com>
To: "Ranjan1018 ." <214748mv@gmail.com>
Subject: Re: Suspend/resume on i915 stop working between r278348 and r278741.
Message-ID: <20150215151141.GB34251@kib.kiev.ua>
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Cc: Adrian Chadd <adrian@freebsd.org>,
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On Sun, Feb 15, 2015 at 03:37:17PM +0100, Ranjan1018 . wrote:
> Hi,
> the bug was introduced in r278473. Suspend/resume works again if I disable
> the x2APIC support with hw.x2apic_enable=0 in /boot/loader.conf, tested in
> r278473 and r278741.

So how it is related to i915 ?

Try the patch.

diff --git a/sys/x86/x86/local_apic.c b/sys/x86/x86/local_apic.c
index 1809fa6..c8ea35e 100644
--- a/sys/x86/x86/local_apic.c
+++ b/sys/x86/x86/local_apic.c
@@ -541,6 +541,9 @@ native_lapic_setup(int boot)
 
 	saveintr = intr_disable();
 
+	if (!boot && x2apic_mode)
+		native_lapic_enable_x2apic();
+
 	la = &lapics[lapic_id()];
 	KASSERT(la->la_present, ("missing APIC structure"));
 	maxlvt = (lapic_read32(LAPIC_VERSION) & APIC_VER_MAXLVT) >> MAXLVTSHIFT;