remarkable-linux/drivers
Suresh Siddha 41750d31fc x86, x2apic: Enable the bios request for x2apic optout
On the platforms which are x2apic and interrupt-remapping
capable, Linux kernel is enabling x2apic even if the BIOS
doesn't. This is to take advantage of the features that x2apic
brings in.

Some of the OEM platforms are running into issues because of
this, as their bios is not x2apic aware. For example, this was
resulting in interrupt migration issues on one of the platforms.
Also if the BIOS SMI handling uses APIC interface to send SMI's,
then the BIOS need to be aware of x2apic mode that OS has
enabled.

On some of these platforms, BIOS doesn't have a HW mechanism to
turnoff the x2apic feature to prevent OS from enabling it.

To resolve this mess, recent changes to the VT-d2 specification:

 http://download.intel.com/technology/computing/vptech/Intel(r)_VT_for_Direct_IO.pdf

includes a mechanism that provides BIOS a way to request system
software to opt out of enabling x2apic mode.

Look at the x2apic optout flag in the DMAR tables before
enabling the x2apic mode in the platform. Also print a warning
that we have disabled x2apic based on the BIOS request.

Kernel boot parameter "intremap=no_x2apic_optout" can be used to
override the BIOS x2apic optout request.

Signed-off-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: yinghai@kernel.org
Cc: joerg.roedel@amd.com
Cc: tony.luck@intel.com
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/20110824001456.171766616@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-09-21 10:21:50 +02:00
..
accessibility
acpi Merge branches 'apei', 'bz-13195' and 'doc' into acpi 2011-09-12 20:00:00 -04:00
amba
ata drivers/ata/sata_dwc_460ex.c: add missing kfree 2011-08-18 23:58:11 -04:00
atm atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
auxdisplay
base Merge branch 'for-linus' of git://opensource.wolfsonmicro.com/regmap 2011-09-08 16:47:52 -07:00
bcma bcma: add uevent to the bus, to autoload drivers 2011-08-22 14:21:41 -04:00
block Merge branch 'stable/for-jens' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen into for-linus 2011-08-09 20:43:26 +02:00
bluetooth Bluetooth: Add Toshiba laptops AR30XX device ID 2011-08-11 19:50:26 -03:00
cdrom drivers/cdrom/cdrom.c: relax check on dvd manufacturer value 2011-08-02 12:43:50 +02:00
char drivers/char/msm_smd_pkt.c: don't use IS_ERR() 2011-08-25 16:25:33 -07:00
clk
clocksource Merge branch 'common/core' into sh-latest 2011-08-08 16:33:54 +09:00
connector proc_fork_connector: a lockless ->real_parent usage is not safe 2011-07-28 18:26:32 -07:00
cpufreq drivers/cpufreq/pcc-cpufreq.c: avoid NULL pointer dereference 2011-09-14 18:09:38 -07:00
cpuidle cpuidle: stop depending on pm_idle 2011-08-03 19:06:37 -04:00
crypto n2_crypto: Attach on Niagara-T3. 2011-07-28 01:30:07 -07:00
dca
dio
dma dmaengine/ste_dma40: fix memory leak due to prepared descriptors 2011-09-05 17:08:26 +05:30
edac i7core_edac: fixed typo in error count calculation 2011-08-18 14:07:15 -07:00
eisa eisa/pci_eisa.c: fix BUG introduced by 005bdad7b8 2011-08-04 06:32:51 -10:00
firewire firewire: ohci: add no MSI quirk for O2Micro controller 2011-09-16 22:22:10 +02:00
firmware firmware: fix google/gsmi.c build warning 2011-08-08 13:53:49 -07:00
gpio drivers/gpio/gpio-generic.c: fix build errors 2011-09-14 18:09:38 -07:00
gpu drm/radeon/kms: Make GPU/CPU page size handling consistent in blit code (v2) 2011-09-18 19:44:36 +01:00
hid Merge branch 'for-linus' of git://github.com/dtor/input 2011-09-16 14:09:19 -07:00
hwmon hwmon: (coretemp) Initialize tmin 2011-09-14 03:55:05 -07:00
hwspinlock
i2c i2c-tegra: fix possible race condition after tx 2011-09-07 00:13:40 +01:00
ide drivers/ide/cy82c693.c: Add missing pci_dev_put 2011-08-04 01:30:34 -07:00
idle
ieee802154
infiniband Merge branches 'ipoib' and 'iser' into for-next 2011-08-17 10:57:43 -07:00
input Merge branch 'for-linus' of git://github.com/dtor/input 2011-09-16 14:09:19 -07:00
iommu x86, x2apic: Enable the bios request for x2apic optout 2011-09-21 10:21:50 +02:00
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2011-07-28 05:58:19 -07:00
leds drivers/leds/ledtrig-timer.c: fix broken sysfs delay handling 2011-09-14 18:09:38 -07:00
lguest
macintosh
mca
md md: Fix handling for devices from 2TB to 4TB in 0.90 metadata. 2011-09-10 17:21:28 +10:00
media [media] vp7045: fix buffer setup 2011-09-11 09:33:41 -03:00
memstick
message Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 2011-07-30 08:36:02 -10:00
mfd mfd: Fix omap-usb-host build failure 2011-09-06 16:37:59 +02:00
misc drivers/misc/pti.c: give 'comm' function scope in pti_control_frame_built_and_sent() 2011-09-14 18:09:38 -07:00
mmc mmc: sdhci-s3c: Fix mmc card I/O problem 2011-08-31 16:25:52 -04:00
mtd UBI: do not link debug messages when debugging is disabled 2011-08-19 19:02:27 +03:00
net Merge git://github.com/davem330/net 2011-09-18 11:02:26 -07:00
nfc NFC: pn533: use after free in pn533_disconnect() 2011-07-26 16:27:24 -04:00
nubus
of Revert "dt: add of_alias_scan and of_alias_get_id" 2011-08-04 11:26:24 +01:00
oprofile atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
parisc
parport Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6 2011-07-25 23:09:27 -07:00
pci pci: Don't crash when reading mpss from root complex 2011-09-13 16:08:31 -07:00
pcmcia Merge git://git.kernel.org/pub/scm/linux/kernel/git/brodo/pcmcia-2.6 2011-07-31 06:23:08 -10:00
platform acer-wmi: support Lenovo ideapad S205 wifi switch 2011-08-05 15:21:52 -04:00
pnp Merge 'akpm' patch series 2011-07-25 21:00:19 -07:00
power s3c-adc-battery: Fix compilation error due to missing header (module.h) 2011-08-19 21:01:46 +04:00
pps
ps3
ptp
rapidio rapidio: fix use of non-compatible registers 2011-08-25 16:25:34 -07:00
regulator Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/lrg/voltage-2.6 2011-08-01 14:05:46 -10:00
rtc drivers/rtc/rtc-s3c.c: fix no occurrence of alarm interrupt 2011-09-14 18:09:38 -07:00
s390 [S390] memory hotplug: only unassign assigned increments 2011-08-24 17:15:24 +02:00
sbus atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
scsi Merge git://bedivere.hansenpartnership.com/git/scsi-rc-fixes-2.6 2011-09-14 16:09:14 -07:00
sfi
sh Merge branch 'common/core' into sh-latest 2011-08-08 16:33:54 +09:00
sn
spi spi/pl022: remove function cannot exit 2011-08-02 14:54:11 +01:00
ssb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-07-25 13:56:39 -07:00
staging staging: fix comedi build when ISA_DMA_API is enabled but COMEDI_PCI is not enabled 2011-09-19 17:15:46 -07:00
target iscsi-target: Fix sendpage breakage with proper padding+DataDigest iovec offsets 2011-09-16 23:47:07 +00:00
tc
telephony
thermal thermal: make THERMAL_HWMON implementation fully internal 2011-08-02 14:51:57 -04:00
tty cris: fix a build error in drivers/tty/serial/crisv10.c 2011-09-14 18:09:38 -07:00
uio Merge branch 'driver-core-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6 2011-07-25 23:06:24 -07:00
usb USB: xHCI: prevent infinite loop when processing MSE event 2011-09-19 17:15:47 -07:00
uwb
vhost atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
video backlight: Declare backlight_types[] const 2011-09-10 14:00:02 -07:00
virt
virtio virtio: expose for non-virtualization users too 2011-07-23 16:20:30 +09:30
vlynq
w1 MAINTAINERS: Evgeniy has moved 2011-08-25 16:25:33 -07:00
watchdog watchdog: Cleanup WATCHDOG_CORE help text 2011-08-02 08:23:07 +00:00
xen xen/irq: Alter the locking to use a mutex instead of a spinlock. 2011-09-15 04:32:02 -04:00
zorro
Kconfig Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00
Makefile Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2011-07-25 22:59:39 -07:00