Commit Graph

87470 Commits

Author SHA1 Message Date
Linus Torvalds
f920bb6f5f Merge branch 'audit.b49' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current
* 'audit.b49' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current:
  [PATCH] export sessionid alongside the loginuid in procfs
2008-03-18 08:43:59 -07:00
Eric Paris
1e0bd7550e [PATCH] export sessionid alongside the loginuid in procfs
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-18 10:51:22 -04:00
Linus Torvalds
d32466912e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: update key codes for Apple aluminium
  HID: fix comment in hid_input_report()
  HID: BADPAD entry for NATSU Playstation USB adapter
  HID: Use DIV_ROUND_UP
  HID: remove HID_QUIRK_APPLE_ISO_KEYBOARD for 4th generation macbook
2008-03-18 07:49:59 -07:00
Linus Torvalds
74fe030532 Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
  ACPI: Set flag DOCK_UNDOCKING when triggered via sysfs
  Revert "ACPI: video: Ignore devices that aren't present in hardware"
  asus_acpi: remove misleading mask
  Revert "ACPI: video: Ignore ACPI video devices that aren't present in hardware"
  thermal: delete "default y"
  thermal: re-document thermal units
  Revert "thermal: fix generic thermal I/F for hwmon"
  ACPI: fix ATA_ACPI build
  ACPI: battery: Don't return -EFAIL on broken packages.
  ACPI: lockdep warning on boot, 2.6.25-rc5
2008-03-18 07:48:23 -07:00
Linus Torvalds
fb00f7629b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: ALPS - fix forward/back buttons reversed on Acer 5520-5290
  Input: ALPS - put secondary device in proper place in sysfs
  Input: wacom - add support for Bamboo1, BambooFun, and Cintiq 12WX
  Input: document i8042.noloop
  Input: add keyboard notifier documentation
  Input: ads7846 - fix uninitialized var warning
  Input: i8042 - add SNI RM support
  Input: i8042 - add Lenovo 3000 N100 to nomux blacklist
  Input: i8042 - fix warning on non-x86 builds
  Input: cobalt_btns - assorted fixes
2008-03-18 07:46:19 -07:00
Linus Torvalds
992ab12ac3 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6:
  make selinux_parse_opts_str() static
2008-03-18 07:44:21 -07:00
Linus Torvalds
92f53c6f1e Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  Revert "unexport bio_{,un}map_user"
  relay: fix subbuf_splice_actor() adding too many pages
  The ps2esdi driver was marked as BROKEN more than two years ago due to being
2008-03-18 07:43:14 -07:00
Linus Torvalds
ff69c00f0a Merge branch 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/ati_pcigart: fix the PCIGART to use drm_pci to allocate GART table.
  drm/radeon: fixup RV550 chip family
  drm/via: attempt again to stabilise the AGP DMA command submission.
  drm: Fix race that can lockup the kernel
2008-03-18 07:32:23 -07:00
Michael Hanselmann
07146648bc HID: update key codes for Apple aluminium
F5 and F6 have no second function printed on them. Thus their definitions have
been removed from the table.

KEY_CYCLEWINDOWS doesn't name the function of Mac OS X' Expose properly and
because we couldn't find a better key code, we decided to use KEY_FN_F4
instead.

We also changed KEY_BACK and KEY_FORWARD, which apply to browser functions, to
KEY_PREVIOUSSONG and KEY_NEXTSONG, since the keys are intended to control a
music player.

Signed-off-by: Michael Hanselmann <linux-kernel@hansmi.ch>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-03-18 11:20:33 +01:00
Jiri Kosina
dfd347f09c HID: fix comment in hid_input_report()
The hid_input_report() in debug mode of course outputs the report itself, not
the device report descriptor.

Fix this error in comment.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-03-18 11:20:32 +01:00
Andrew Burton
c9bde7ad39 HID: BADPAD entry for NATSU Playstation USB adapter
Add quirk entry for BADPAD for the NATSU Playstation USB adapter. The
adapter is supported under Linux, but with bad direction detection.

Signed-off-by: Andrew Burton <adb@iinet.net.au>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-03-18 11:20:31 +01:00
Julia Lawall
92c4a1b9f2 HID: Use DIV_ROUND_UP
The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-03-18 11:20:30 +01:00
Tobias Mueller
790c9d8d87 HID: remove HID_QUIRK_APPLE_ISO_KEYBOARD for 4th generation macbook
4th generation MacBook (product id 0x022a) from Apple doesn't need
HID_QUIRK_APPLE_ISO_KEYBOARD fix anymore.

Signed-off-by: Tobias Mueller <Tobias_Mueller@twam.info>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-03-18 11:20:30 +01:00
Len Brown
13d93924f1 Merge branches 'release' and 'dock' into release 2008-03-18 05:17:15 -04:00
Holger Macht
9171f83488 ACPI: Set flag DOCK_UNDOCKING when triggered via sysfs
begin_undock() is only called when triggered via a acpi notify handler
(pressing the undock button on the dock station), but complete_undock() is
always called after the eject. So if a undock is triggered through a sysfs
write, the flag DOCK_UNDOCKING has to be set for the dock station,
too. Otherwise this will freeze the system hard.

Signed-off-by: Holger Macht <hmacht@suse.de>
Acked-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-18 05:16:38 -04:00
Len Brown
d9ea1364d3 Merge branches 'release', 'asus', 'bugzilla-8573', 'bugzilla-9995', 'bugzilla-10272', 'lockdep' and 'thermal' into release 2008-03-18 04:52:57 -04:00
Len Brown
77321e624b Revert "ACPI: video: Ignore devices that aren't present in hardware"
This reverts commit 0119509c4f.

http://bugzilla.kernel.org/show_bug.cgi?id=9995

Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-18 04:04:35 -04:00
Julia Lawall
abc5a87f4e asus_acpi: remove misleading mask
led_out is boolean, so there is no functional change here,
but apparently an extra mask with 1 caused some style checkers
to flag this as logic bug.

Signed-off-by: Julia Lawall <julia@diku.dk>
Acked-by: Luca Tettamanti <kronos.it@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-18 02:31:34 -04:00
Len Brown
f0d6752c9f Revert "ACPI: video: Ignore ACPI video devices that aren't present in hardware"
This reverts commit 3fa2cdcc45.

http://bugzilla.kernel.org/show_bug.cgi?id=9995

Signed-off-by: Len Brown <len.brown>
2008-03-18 01:43:53 -04:00
Len Brown
ece54e2ff4 thermal: delete "default y"
The generic thermal I/F gets selected by ACPI_THERMAL --
its only current customer.
it doesn't need to clutter other configs by default.

Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-18 01:22:10 -04:00
Zhang, Rui
6d7f014e55 thermal: re-document thermal units
From: Zhang Rui <rui.zhang@intel.com>

(reverting the previous sysfs patch also reverted a fix
 to the thermal units documentation, which is restored by this commit)

The generic thermal driver shows temperature in millidegree Celsius.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-18 01:21:21 -04:00
Len Brown
91f57fa121 Revert "thermal: fix generic thermal I/F for hwmon"
This reverts commit 3152fb9f11.

This broke libsensors.

Acked-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-18 01:14:37 -04:00
Laszlo Kajan
3c00bb9649 Input: ALPS - fix forward/back buttons reversed on Acer 5520-5290
ALPS_FW_BK_1 protocol flavor seems to have forward and backward
keys reversed.

Signed-off-by: Laszlo Kajan <kajla@bioinfo.pl>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2008-03-18 00:39:55 -04:00
Dmitry Torokhov
1db3a3453f Input: ALPS - put secondary device in proper place in sysfs
Secondary input device did not have parent set up causing it
to appear in the root of sysfs device hierarchy.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2008-03-18 00:29:18 -04:00
Len Brown
0ac4a3c2fb ACPI: fix ATA_ACPI build
drivers/ata/libata-acpi.c fails to build

drivers/built-in.o: In function `ata_acpi_associate':
(.text+0x7106a): undefined reference to `register_hotplug_dock_device'

When CONFIG_ATA_ACPI=y and CONFIG_ACPI_DOCK=m
But if dock is selected from ata_acpi, dock will =y
when ata_acpi=y, avoiding this problem.

http://bugzilla.kernel.org/show_bug.cgi?id=10272

Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-18 00:26:07 -04:00
Alexey Starikovskiy
b8a1bdb149 ACPI: battery: Don't return -EFAIL on broken packages.
Acer BIOS has a bug which is exposed when a dead battery is present.

The package template that is used to describe battery status is
over-written with sane values when the battery is live.
But when the batter is dead, a bogus reference in the template
is used.  In this case, Linux returns a fault, when instead
it should simply return that it doesn't know the missing value.

http://bugzilla.kernel.org/show_bug.cgi?id=8573
http://bugzilla.kernel.org/show_bug.cgi?id=10202

Signed-off-by: Alexey Starikovskiy <astarikovskiy@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>
2008-03-17 22:37:42 -04:00
Mark Lord
9e58582449 pciehp: don't enable slot unless forced
This fixes a 2.6.25 regression reported by Alex Chiang.

Invoke pciehp_enable_slot() at startup only when pciehp_force=1.
Some HP equipment apparently cannot cope with it otherwise.

This restores the (previously working) 2.6.24 behaviour here,
while allowing machines that need a kick to use pciehp_force=1.

This was the original design back in October 2007,
but Kristen suggested we try without it first:

   Kristen Carlson Accardi wrote:
   >I think it would be ok to try allowing the slot to be enabled when not
   >using pciehp_force mode.  We can wrap it later if it proves to break things

This ended up breaking one of Alex's setups,
so it's time to put the wrapper back in now.

Signed-off-by: Mark Lord <mlord@pobox.com>
Acked-by: Alex Chiang <achiang@hp.com>
Acked-by: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-17 19:26:05 -07:00
Adrian Bunk
2e1479d95d make selinux_parse_opts_str() static
This patch makes the needlessly global selinux_parse_opts_str() static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-03-18 09:17:22 +11:00
Jens Axboe
40044ce0bf Revert "unexport bio_{,un}map_user"
Outside users like asmlib uses the mapping functions. API wise, the
export is definitely sane. It's a better idea to keep this export
than to require external users to open-code this piece of code instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-17 21:14:40 +01:00
Linus Torvalds
bde4f8fa8d Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
  ahci: Add Marvell 6121 SATA support
  pata_ali: use atapi_cmd_type() to determine cmd type instead of transfer size
  ahci: implement skip_host_reset parameter
  ahci: request all PCI BARs
  devres: implement pcim_iomap_regions_request_all()
  libata-acpi: improve dock event handling
2008-03-17 09:52:24 -07:00
Linus Torvalds
84841384ec Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  virtio: fix race in enable_cb
  virtio: Enable netpoll interface for netconsole logging
  virtio: handle > 2 billion page balloon targets
  virtio: Fix sysfs bits to have proper block symlink
  virtio: Use spin_lock_irqsave/restore for virtio-pci
2008-03-17 09:52:19 -07:00
Al Viro
3d10a15d69 hfs_bnode_find() can fail, resulting in hfs_bnode_split() breakage
oops and fs corruption; the latter can happen even on valid fs in case of oom.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-17 09:46:55 -07:00
Jose Alberto Reguero
c40e7cb89f ahci: Add Marvell 6121 SATA support
Signed-off-by: Jose Alberto Reguero <jareguero@telefonica.net>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-17 08:30:32 -04:00
Tejun Heo
4a38e733a7 pata_ali: use atapi_cmd_type() to determine cmd type instead of transfer size
pata_ali was using qc->nbytes to determine whether a command is
data transfer type or not.  As now qc->nbytes can be extended by
padding and draining buffers, these tests are not useful anymore.

Use atapi_cmd_type() instead.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-17 08:26:52 -04:00
Tejun Heo
a22e64443f ahci: implement skip_host_reset parameter
Under certain circumstances (SSP turned off by the BIOS) and for
debugging purposes, skipping global controller reset is helpful.  Add
a kernel parameter for it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-17 08:26:50 -04:00
Tejun Heo
dea5513763 ahci: request all PCI BARs
ahci is often implemented with accompanying SFF compatible interface
and legacy IDE driver may attach to the legacy IO ports when the
controller is already claimed by ahci and vice-versa.  This patch
makes ahci use pcim_iomap_regions_request_all() so that all IO regions
are claimed on attach.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-17 08:26:47 -04:00
Tejun Heo
916fbfb7ae devres: implement pcim_iomap_regions_request_all()
Some drivers need to reserve all PCI BARs to prevent other drivers
misusing unoccupied BARs.  pcim_iomap_regions_request_all() requests
all BARs and iomap specified BARs.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-17 08:26:44 -04:00
Tejun Heo
233f112042 libata-acpi: improve dock event handling
Improve ACPI hotplug handling such that dock event is handled properly.

* Register handlers for dock events.

* Directly detach device on EJECT_REQUEST instead of signaling hotplug
  event.  This prevents libata from accessing severed controller
  and/or device.

* While at it, use named constants for ACPI events and move uevent
  signaling inside host lock.

Original patch and testing by Holger Macht.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Holger Macht <hmacht@suse.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
2008-03-17 08:26:42 -04:00
Christian Borntraeger
4265f161b6 virtio: fix race in enable_cb
There is a race in virtio_net, dealing with disabling/enabling the callback.
I saw the following oops:

kernel BUG at /space/kvm/drivers/virtio/virtio_ring.c:218!
illegal operation: 0001 [#1] SMP
Modules linked in: sunrpc dm_mod
CPU: 2 Not tainted 2.6.25-rc1zlive-host-10623-gd358142-dirty #99
Process swapper (pid: 0, task: 000000000f85a610, ksp: 000000000f873c60)
Krnl PSW : 0404300180000000 00000000002b81a6 (vring_disable_cb+0x16/0x20)
           R:0 T:1 IO:0 EX:0 Key:0 M:1 W:0 P:0 AS:0 CC:3 PM:0 EA:3
Krnl GPRS: 0000000000000001 0000000000000001 0000000010005800 0000000000000001
           000000000f3a0900 000000000f85a610 0000000000000000 0000000000000000
           0000000000000000 000000000f870000 0000000000000000 0000000000001237
           000000000f3a0920 000000000010ff74 00000000002846f6 000000000fa0bcd8
Krnl Code: 00000000002b819a: a7110001           tmll    %r1,1
           00000000002b819e: a7840004           brc     8,2b81a6
           00000000002b81a2: a7f40001           brc     15,2b81a4
          >00000000002b81a6: a51b0001           oill    %r1,1
           00000000002b81aa: 40102000           sth     %r1,0(%r2)
           00000000002b81ae: 07fe               bcr     15,%r14
           00000000002b81b0: eb7ff0380024       stmg    %r7,%r15,56(%r15)
           00000000002b81b6: a7f13e00           tmll    %r15,15872
Call Trace:
([<000000000fa0bcd0>] 0xfa0bcd0)
 [<00000000002b8350>] vring_interrupt+0x5c/0x6c
 [<000000000010ab08>] do_extint+0xb8/0xf0
 [<0000000000110716>] ext_no_vtime+0x16/0x1a
 [<0000000000107e72>] cpu_idle+0x1c2/0x1e0

The problem can be triggered with a high amount of host->guest traffic.
I think its the following race:

poll says netif_rx_complete
poll calls enable_cb
enable_cb opens the interrupt mask
a new packet comes, an interrupt is triggered----\
enable_cb sees that there is more work           |
enable_cb disables the interrupt                 |
       .                                         V
       .                            interrupt is delivered
       .                            skb_recv_done does atomic napi test, ok
 some waiting                       disable_cb is called->check fails->bang!
       .
poll would do napi check
poll would do disable_cb

The fix is to let enable_cb not disable the interrupt again, but expect the
caller to do the cleanup if it returns false. In that case, the interrupt is
only disabled, if the napi test_set_bit was successful.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (cleaned up doco)
2008-03-17 22:58:21 +11:00
Amit Shah
da74e89d40 virtio: Enable netpoll interface for netconsole logging
Add a new poll_controller handler that the netpoll interface needs.

This enables netconsole logging from a kvm guest over the virtio
net interface.

Signed-off-by: Amit Shah <amitshah@gmx.net>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-17 22:58:20 +11:00
Rusty Russell
bdc1681cdf virtio: handle > 2 billion page balloon targets
If the host asks for a huge target towards_target() can overflow, and
we up oops as we try to release more pages than we have.  The simple
fix is to use a 64-bit value.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-17 22:58:19 +11:00
Jeremy Katz
c483934670 virtio: Fix sysfs bits to have proper block symlink
Fix up so that the virtio_blk devices in sysfs link correctly to their
block device.  This then allows them to be detected by hal, etc

Signed-off-by: Jeremy Katz <katzj@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-17 22:58:15 +11:00
Anthony Liguori
27ebe308af virtio: Use spin_lock_irqsave/restore for virtio-pci
virtio-pci acquires its spin lock in an interrupt context so it's necessary
to use spin_lock_irqsave/restore variants.  This patch fixes guest SMP when
using virtio devices in KVM.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2008-03-17 22:58:13 +11:00
Jens Axboe
16d5466942 relay: fix subbuf_splice_actor() adding too many pages
If subbuf_pages was larger than the max number of pages the pipe
buffer will hold, subbuf_splice_actor() would happily go beyond
the array size.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-17 09:04:59 +01:00
Adrian Bunk
2af3e6017e The ps2esdi driver was marked as BROKEN more than two years ago due to being
no longer working for some time.

A driver that had been marked as BROKEN for such a long time seems to be
unlikely to be revived in the forseeable future.

But if anyone wants to ever revive this driver, the code is still present in
the older kernel releases.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2008-03-17 09:03:05 +01:00
Dave Airlie
b05c23851a drm/ati_pcigart: fix the PCIGART to use drm_pci to allocate GART table.
This fixes a problem on 64-bit with 4GB with ATI RS690 chipsets. It
makes sure the pcigart table is allocated in coherent memory for DMA operations.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2008-03-17 10:24:24 +10:00
Alex Deucher
16d3be46d9 drm/radeon: fixup RV550 chip family
This fixes up the RV550 chips which are based on RV515, not RV530.
It also adds another RS690 PCI ID.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2008-03-17 10:22:12 +10:00
Thomas Hellstrom
f0fb6d7798 drm/via: attempt again to stabilise the AGP DMA command submission.
It's worth remembering that all new bright ideas on how to make this command reader work properly and according to docs will probably fail :( Bring in some old code.

Also allow a larger SG-DMA download stride, and remove unnecessary waits for
command regulators pauses.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2008-03-17 10:07:20 +10:00
Mike Isely
9df5808cca drm: Fix race that can lockup the kernel
The i915_vblank_swap() function schedules an automatic buffer swap
upon receipt of the vertical sync interrupt.  Such an operation is
lengthy so it can't be allowed to happen in normal interrupt context,
thus the DRM implements this by scheduling the work in a kernel
softirq-scheduled tasklet.  In order for the buffer swap to work
safely, the DRM's central lock must be taken, via a call to
drm_lock_take() located in drivers/char/drm/drm_irq.c within the
function drm_locked_tasklet_func().  The lock-taking logic uses a
non-interrupt-blocking spinlock to implement the manipulations needed
to take the lock.  This semantic would be safe if all attempts to use
the spinlock only happen from process context.  However this buffer
swap happens from softirq context which is really a form of interrupt
context.  Thus we have an unsafe situation, in that
drm_locked_tasklet_func() can block on a spinlock already taken by a
thread in process context which will never get scheduled again because
of the blocked softirq tasklet.  This wedges the kernel hard.

To trigger this bug, run a dual-head cloned mode configuration which
uses the i915 drm, then execute an opengl application which
synchronizes buffer swaps against the vertical sync interrupt.  In my
testing, a lockup always results after running anywhere from 5 minutes
to an hour and a half.  I believe dual-head is needed to really
trigger the problem because then the vertical sync interrupt handling
is no longer predictable (due to being interrupt-sourced from two
different heads running at different speeds).  This raises the
probability of the tasklet trying to run while the userspace DRI is
doing things to the GPU (and manipulating the DRM lock).

The fix is to change the relevant spinlock semantics to be the
interrupt-blocking form.  After this change I am no longer able to
trigger the lockup; the longest test run so far was 20 hours (test
stopped after that point).

Note: I have examined the places where this spinlock is being
employed; all are reasonably short bounded sequences and should be
suitable for interrupts being blocked without impacting overall kernel
interrupt response latency.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2008-03-17 09:54:58 +10:00
Linus Torvalds
a978b30af3 Linux 2.6.25-rc6 2008-03-16 16:32:14 -07:00