Commit graph

87431 commits

Author SHA1 Message Date
Christoph Hellwig 322ee5b36e [PATCH] check for null vfsmount in dentry_open()
Make sure no-one calls dentry_open with a NULL vfsmount argument and crap
out with a stacktrace otherwise.  A NULL file->f_vfsmnt has always been
problematic, but with the per-mount r/o tracking we can't accept anymore
at all.

[AV] the last place that passed NULL had been eliminated by the previous
patch (reiserfs xattr stuff)

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-19 06:50:44 -04:00
Jeff Mahoney 3227e14c3c [PATCH] reiserfs: eliminate private use of struct file in xattr
After several posts and bug reports regarding interaction with the NULL
nameidata, here's a patch to clean up the mess with struct file in the
reiserfs xattr code.

As observed in several of the posts, there's really no need for struct file
to exist in the xattr code.  It was really only passed around due to the
f_op->readdir() and a_ops->{prepare,commit}_write prototypes requiring it.

reiserfs_prepare_write() and reiserfs_commit_write() don't actually use the
struct file passed to it, and the xattr code uses a private version of
reiserfs_readdir() to enumerate the xattr directories.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-19 06:49:36 -04:00
Al Viro f382d6e631 [PATCH] sanitize hppfs
* hppfs_iget() and its users are racy; there's no need to pollute icache
  anyway, new_inode() works fine and is safe, unlike the current kludges
  (these relied on overwriting ->i_ino before another iget_locked() gets
  to that one - and did it after unlocking).
* merge hppfs_iget()/init_inode()/hppfs_read_inode(), while we are
  at it.
* to pass proper vfsmount to dentry_open() store the reference
  in hppfs superblock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 --
2008-03-19 06:42:18 -04:00
Dave Hansen 1dd0dd111f hppfs pass vfsmount to dentry_open()
Here's patch for hppfs that uses vfs_kern_mount to make sure it always has a
procfs instance and passed the vfsmount on through the inode private data.
Also fixes a procfs file_system_type leak for every attempted hppfs mount.

[ jdike - gave this file a style workover, plus deleted hppfs_dentry_ops ]

Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-19 06:39:56 -04:00
Al Viro 8a4e98d9d7 [PATCH] restore export of do_kern_mount()
vfs_kern_mount() requires having a reference to fs type, which
makes it impossible for module to create procfs, etc. private
mount.  Open-coding is not an option, since e.g. put_filesystem()
is _not_ exported, and for a good reason.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-03-17 22:58:04 -04:00
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
Linus Torvalds a978b30af3 Linux 2.6.25-rc6 2008-03-16 16:32:14 -07:00
Linus Torvalds 69d1d523cc Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6:
  [PARISC] make ptr_to_pide() static
  [PARISC] head.S: section mismatch fixes
  [PARISC] add back Crestone Peak cpu
  [PARISC] futex: special case cmpxchg NULL in kernel space
  [PARISC] clean up show_stack
  [PARISC] add pa8900 CPUs to hardware inventory
  [PARISC] clean up include/asm-parisc/elf.h
  [PARISC] move defconfig to arch/parisc/configs/
  [PARISC] add back AD1889 MAINTAINERS entry
  [PARISC] pdc_console: fix bizarre panic on boot
  [PARISC] dump_stack in show_regs
  [PARISC] pdc_stable: fix compile errors
  [PARISC] remove unused pdc_iodc_printf function
  [PARISC] bump __NR_syscalls
  [PARISC] unbreak pgalloc.h
  [PARISC] move VMALLOC_* definitions to fixmap.h
  [PARISC] wire up timerfd syscalls
  [PARISC] remove old timerfd syscall
2008-03-16 10:48:23 -07:00
FUJITA Tomonori 56ee0cfd09 [PARISC] make ptr_to_pide() static
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:17:12 -07:00
Helge Deller 0c634cc629 [PARISC] head.S: section mismatch fixes
- move boot_args[] into the init section
- move $global$ into the read_mostly section
- fix the following two section mismatches:
WARNING: vmlinux.o(.text+0x9c): Section mismatch: reference to .init.text:start_kernel (between '$pgt_fill_loop' and '$is_pa20')
WARNING: vmlinux.o(.text+0xa0): Section mismatch: reference to .init.text:start_kernel (between '$pgt_fill_loop' and '$is_pa20')

Signed-off-by: Helge Deller <deller@gmx.de>
SIgned-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:22 -07:00
Kyle McMartin ab86adb41f [PARISC] add back Crestone Peak cpu
Crestone Peak Slow is the 800MHz PA-8800 cpu in the C8000.
0x88B is probably the Crestone Peak Fast.

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:19 -07:00
Kyle McMartin c20a84c910 [PARISC] futex: special case cmpxchg NULL in kernel space
Commit a0c1e9073e added code to futex.c
to detect whether futex_atomic_cmpxchg_inatomic was implemented at run
time:

+       curval = cmpxchg_futex_value_locked(NULL, 0, 0);
+       if (curval == -EFAULT)
+               futex_cmpxchg_enabled = 1;

This is bogus on parisc, since page zero in kernel virtual space is the
gateway page for syscall entry, and should not be read from the kernel.
(That, and we really don't like the kernel faulting on its own address
 space...)

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:17 -07:00
Kyle McMartin dc39455e79 [PARISC] clean up show_stack
When we show_regs, we obviously have a struct pt_regs of the calling
frame. Use these in show_stack so we don't have the entire bogus call trace
up to the show_stack call.

Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:15 -07:00
James Bottomley b23f5baab3 [PARISC] add pa8900 CPUs to hardware inventory
This patch adds the known pa8900 CPUs to the inventory list and removes
the Crestone Peak one which apparently never escaped into the wild.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:13 -07:00
Randolph Chung fd5d3f6a32 [PARISC] clean up include/asm-parisc/elf.h
Cleanup some cruft. No functionality changes.

Signed-off-by: Randolph Chung <tausq@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:10 -07:00
Adrian Bunk c04f7ae2da [PARISC] move defconfig to arch/parisc/configs/
This patch moves the default parisc defconfig to
arch/parisc/configs/generic_defconfig where it belongs and selects it as
the default defconfig through KBUILD_DEFCONFIG.

Signed-off-by: Adrian Bunk <adrian.bunk@movial.fi>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:08 -07:00
Thibaut VARENE 2f39d51981 [PARISC] add back AD1889 MAINTAINERS entry
Signed-off-by: Thibaut VARENE <T-Bone@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
2008-03-15 19:12:06 -07:00
Kyle McMartin ef1afd4d79 [PARISC] pdc_console: fix bizarre panic on boot
Commit 721fdf3416 introduced a subtle bug
by accidently removing the "static" from iodc_dbuf. This resulted in, what
appeared to be, a trap without *current set to a task. Probably the result of
a trap in real mode while calling firmware.

Also do other misc clean ups. Since the only input from firmware is non
blocking, share iodc_dbuf between input and output, and spinlock the
only callers.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:12:03 -07:00
Kyle McMartin d0347b49c9 [PARISC] dump_stack in show_regs
Originally, show_stack was used in BUG() output. However, a recent commit
changed it to print register state (no idea what that's supposed to help,
really...) and parisc was missing a backtrace because of it.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:12:01 -07:00
Joel Soete ff451d7059 [PARISC] pdc_stable: fix compile errors
Signed-off-by: Joel Soete <rubisher@scarlet.be>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:59 -07:00
Kyle McMartin 179183bf1f [PARISC] remove unused pdc_iodc_printf function
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:56 -07:00
Kyle McMartin e2be75ae21 [PARISC] bump __NR_syscalls
oops, forgot this in the previous commit.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:54 -07:00
Kyle McMartin 9aa150b8d8 [PARISC] unbreak pgalloc.h
Commit 2f569afd9c broke the compile
rather spectacularly. Fix code errors.

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:52 -07:00
Kyle McMartin d912e1dc8b [PARISC] move VMALLOC_* definitions to fixmap.h
They make way more sense here, really...

Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:49 -07:00
Kyle McMartin ff80c66ab6 [PARISC] wire up timerfd syscalls
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:47 -07:00
Kyle McMartin 0cb845ec37 [PARISC] remove old timerfd syscall
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2008-03-15 19:11:45 -07:00
Linus Torvalds 9a9e0d6855 ACPI: Remove ACPI_CUSTOM_DSDT_INITRD option
This essentially reverts commit 71fc47a9ad
("ACPI: basic initramfs DSDT override support"), because the code simply
isn't ready.

It did ugly things to the init sequence to populate the rootfs image
early, but that just ended up showing other problems with the whole
approach.  The fact is, the VFS layer simply isn't initialized this
early, and the relevant ACPI code should either run much later, or this
shouldn't be done at all.

For 2.6.25, we'll just pick the latter option.  We can revisit this
concept later if necessary.

Cc: Dave Hansen <haveblue@us.ibm.com>
Cc: Tilman Schmidt <tilman@imap.cc>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Eric Piel <eric.piel@tremplin-utc.net>
Cc: Len Brown <len.brown@intel.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Markus Gaugusch <dsdt@gaugusch.at>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-15 11:58:04 -07:00
Roel Kluin ce63645234 tifm_sd: DATA_CARRY is not boolean in tifm_sd_transfer_data()
DATA_CARRY is not boolean

Signed-off-by: Roel Kluin <12o3l@tiscali.nl>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-03-15 09:24:21 -07:00
Linus Torvalds afbf331ed1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
  [NET]: Fix tbench regression in 2.6.25-rc1
2008-03-15 09:21:04 -07:00
Ingo Molnar 6a6029b8ce sched: simplify sched_slice()
Use the existing calc_delta_mine() calculation for sched_slice(). This
saves a divide and simplifies the code because we share it with the
other /cfs_rq->load users.

It also improves code size:

      text    data     bss     dec     hex filename
     42659    2740     144   45543    b1e7 sched.o.before
     42093    2740     144   44977    afb1 sched.o.after

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2008-03-15 03:02:50 +01:00
Ingo Molnar e22ecef1d2 sched: fix fair sleepers
Fair sleepers need to scale their latency target down by runqueue
weight. Otherwise busy systems will gain ever larger sleep bonus.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2008-03-15 03:02:50 +01:00
Peter Zijlstra aa2ac25229 sched: fix overload performance: buddy wakeups
Currently we schedule to the leftmost task in the runqueue. When the
runtimes are very short because of some server/client ping-pong,
especially in over-saturated workloads, this will cycle through all
tasks trashing the cache.

Reduce cache trashing by keeping dependent tasks together by running
newly woken tasks first. However, by not running the leftmost task first
we could starve tasks because the wakee can gain unlimited runtime.

Therefore we only run the wakee if its within a small
(wakeup_granularity) window of the leftmost task. This preserves
fairness, but does alternate server/client task groups.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-15 03:02:50 +01:00
Ingo Molnar 27d1172660 sched: fix calc_delta_mine()
lw->weight can be 0 for a short time during bootup.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2008-03-15 03:02:50 +01:00
Ingo Molnar e89996ae3f sched: fix update_load_add()/sub()
Clear the cached inverse value when updating load. This is needed for
calc_delta_mine() to work correctly when using the rq load.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
2008-03-15 03:02:49 +01:00
Peter Zijlstra 3fe69747da sched: min_vruntime fix
Current min_vruntime tracking is incorrect and will cause serious
problems when we don't run the leftmost task for some reason.

min_vruntime does two things; 1) it's used to determine a forward
direction when the u64 vruntime wraps, 2) it's used to track the
leftmost vruntime to position newly enqueued tasks from.

The current logic advances min_vruntime whenever the current task's
vruntime advance. Because the current task may pass the leftmost task
still waiting we're failing the second goal. This causes new tasks to be
placed too far ahead and thus penalizes their runtime.

Fix this by making min_vruntime the min_vruntime of the waiting tasks by
tracking it in enqueue/dequeue, and compare against current's vruntime
to obtain the absolute minimum when placing new tasks.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-15 03:02:49 +01:00
Hiroshi Shimamoto 0e1f34833b sched: fix race in schedule()
Fix a hard to trigger crash seen in the -rt kernel that also affects
the vanilla scheduler.

There is a race condition between schedule() and some dequeue/enqueue
functions; rt_mutex_setprio(), __setscheduler() and sched_move_task().

When scheduling to idle, idle_balance() is called to pull tasks from
other busy processor. It might drop the rq lock. It means that those 3
functions encounter on_rq=0 and running=1. The current task should be
put when running.

Here is a possible scenario:

   CPU0                               CPU1
    |                              schedule()
    |                              ->deactivate_task()
    |                              ->idle_balance()
    |                              -->load_balance_newidle()
rt_mutex_setprio()                     |
    |                              --->double_lock_balance()
    *get lock                          *rel lock
    * on_rq=0, ruuning=1               |
    * sched_class is changed           |
    *rel lock                          *get lock
    :                                  |
                                       :
                                   ->put_prev_task_rt()
                                   ->pick_next_task_fair()
                                       => panic

The current process of CPU1(P1) is scheduling. Deactivated P1, and the
scheduler looks for another process on other CPU's runqueue because CPU1
will be idle. idle_balance(), load_balance_newidle() and
double_lock_balance() are called and double_lock_balance() could drop
the rq lock. On the other hand, CPU0 is trying to boost the priority of
P1. The result of boosting only P1's prio and sched_class are changed to
RT. The sched entities of P1 and P1's group are never put. It makes
cfs_rq invalid, because the cfs_rq has curr and no leaf, but
pick_next_task_fair() is called, then the kernel panics.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-03-15 03:02:49 +01:00
Linus Torvalds 4faa849665 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: fw-ohci: shut up false compiler warning on PPC32
  firewire: fw-ohci: use dma_alloc_coherent for ar_buffer
  ieee1394: sbp2: fix for SYM13FW500 bridge (Datafab disk)
  firewire: fw-sbp2: fix for SYM13FW500 bridge (Datafab disk)
  firewire: update Kconfig help text
  firewire: warn on fatal condition in topology code
  firewire: fw-sbp2: set single-phase retry_limit
  firewire: fw-ohci: Apple UniNorth 1st generation support
  firewire: fw-ohci: PPC PMac platform code
  firewire: endianess annotations
  firewire: endianess fix
2008-03-14 16:49:41 -07:00