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  1. 11 9月, 2007 2 次提交
    • N
      [NETFILTER]: Fix/improve deadlock condition on module removal netfilter · 16fcec35
      由 Neil Horman 提交于 
      So I've had a deadlock reported to me.  I've found that the sequence of
events goes like this:

1) process A (modprobe) runs to remove ip_tables.ko

2) process B (iptables-restore) runs and calls setsockopt on a netfilter socket,
increasing the ip_tables socket_ops use count

3) process A acquires a file lock on the file ip_tables.ko, calls remove_module
in the kernel, which in turn executes the ip_tables module cleanup routine,
which calls nf_unregister_sockopt

4) nf_unregister_sockopt, seeing that the use count is non-zero, puts the
calling process into uninterruptible sleep, expecting the process using the
socket option code to wake it up when it exits the kernel

4) the user of the socket option code (process B) in do_ipt_get_ctl, calls
ipt_find_table_lock, which in this case calls request_module to load
ip_tables_nat.ko

5) request_module forks a copy of modprobe (process C) to load the module and
blocks until modprobe exits.

6) Process C. forked by request_module process the dependencies of
ip_tables_nat.ko, of which ip_tables.ko is one.

7) Process C attempts to lock the request module and all its dependencies, it
blocks when it attempts to lock ip_tables.ko (which was previously locked in
step 3)

Theres not really any great permanent solution to this that I can see, but I've
developed a two part solution that corrects the problem

Part 1) Modifies the nf_sockopt registration code so that, instead of using a
use counter internal to the nf_sockopt_ops structure, we instead use a pointer
to the registering modules owner to do module reference counting when nf_sockopt
calls a modules set/get routine.  This prevents the deadlock by preventing set 4
from happening.

Part 2) Enhances the modprobe utilty so that by default it preforms non-blocking
remove operations (the same way rmmod does), and add an option to explicity
request blocking operation.  So if you select blocking operation in modprobe you
can still cause the above deadlock, but only if you explicity try (and since
root can do any old stupid thing it would like....  :)  ).
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      16fcec35
    • J
      [libata, IDE] add new VIA bridge to VIA PATA drivers · b311ec4a
      由 Joseph Chan 提交于 
      Signed-off-by: NJoseph Chan <josephchan@via.com.tw>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
      b311ec4a
  3. 01 9月, 2007 1 次提交
    • T
      NFS: Fix a write request leak in nfs_invalidate_page() · 1b3b4a1a
      由 Trond Myklebust 提交于 
      Ryusuke Konishi says:

The recent truncate_complete_page() clears the dirty flag from a page
before calling a_ops->invalidatepage(),
^^^^^^
static void
truncate_complete_page(struct address_space *mapping, struct page *page)
{
        ...
        cancel_dirty_page(page, PAGE_CACHE_SIZE);  <--- Inserted here at
kernel 2.6.20

        if (PagePrivate(page))
                do_invalidatepage(page, 0);   ---> will call
a_ops->invalidatepage()
        ...
}

and this is disturbing nfs_wb_page_priority() from calling 
nfs_writepage_locked() that is expected to handle the pending
request (=nfs_page) associated with the page.

int nfs_wb_page_priority(struct inode *inode, struct page *page, int how)
{
        ...
        if (clear_page_dirty_for_io(page)) {
                ret = nfs_writepage_locked(page, &wbc);
                if (ret < 0)
                        goto out;
        }
        ...
}

Since truncate_complete_page() will get rid of the page after
a_ops->invalidatepage() returns, the request (=nfs_page) associated
with the page becomes a garbage in nfs_inode->nfs_page_tree.
------------------------

Fix this by ensuring that nfs_wb_page_priority() recognises that it may
also need to clear out non-dirty pages that have an nfs_page associated
with them.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      1b3b4a1a
  5. 31 8月, 2007 7 次提交
  7. 28 8月, 2007 1 次提交
    • I
      sched: make the scheduler converge to the ideal latency · f6cf891c
      由 Ingo Molnar 提交于 
      de-HZ-ification of the granularity defaults unearthed a pre-existing
property of CFS: while it correctly converges to the granularity goal,
it does not prevent run-time fluctuations in the range of
[-gran ... 0 ... +gran].

With the increase of the granularity due to the removal of HZ
dependencies, this becomes visible in chew-max output (with 5 tasks
running):

 out:  28 . 27. 32 | flu:  0 .  0 | ran:    9 .   13 | per:   37 .   40
 out:  27 . 27. 32 | flu:  0 .  0 | ran:   17 .   13 | per:   44 .   40
 out:  27 . 27. 32 | flu:  0 .  0 | ran:    9 .   13 | per:   36 .   40
 out:  29 . 27. 32 | flu:  2 .  0 | ran:   17 .   13 | per:   46 .   40
 out:  28 . 27. 32 | flu:  0 .  0 | ran:    9 .   13 | per:   37 .   40
 out:  29 . 27. 32 | flu:  0 .  0 | ran:   18 .   13 | per:   47 .   40
 out:  28 . 27. 32 | flu:  0 .  0 | ran:    9 .   13 | per:   37 .   40

average slice is the ideal 13 msecs and the period is picture-perfect 40
msecs. But the 'ran' field fluctuates around 13.33 msecs and there's no
mechanism in CFS to keep that from happening: it's a perfectly valid
solution that CFS finds.

to fix this we add a granularity/preemption rule that knows about
the "target latency", which makes tasks that run longer than the ideal
latency run a bit less. The simplest approach is to simply decrease the
preemption granularity when a task overruns its ideal latency. For this
we have to track how much the task executed since its last preemption.

( this adds a new field to task_struct, but we can eliminate that
  overhead in 2.6.24 by putting all the scheduler timestamps into an
  anonymous union. )

with this change in place, chew-max output is fluctuation-less all
around:

 out:  28 . 27. 39 | flu:  0 .  2 | ran:   13 .   13 | per:   41 .   40
 out:  28 . 27. 39 | flu:  0 .  2 | ran:   13 .   13 | per:   41 .   40
 out:  28 . 27. 39 | flu:  0 .  2 | ran:   13 .   13 | per:   41 .   40
 out:  28 . 27. 39 | flu:  0 .  2 | ran:   13 .   13 | per:   41 .   40
 out:  28 . 27. 39 | flu:  0 .  1 | ran:   13 .   13 | per:   41 .   40
 out:  28 . 27. 39 | flu:  0 .  1 | ran:   13 .   13 | per:   41 .   40

this patch has no impact on any fastpath or on any globally observable
scheduling property. (unless you have sharp enough eyes to see
millisecond-level ruckles in glxgears smoothness :-)
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NMike Galbraith <efault@gmx.de>
      f6cf891c
  9. 27 8月, 2007 2 次提交
  11. 26 8月, 2007 2 次提交
  13. 25 8月, 2007 2 次提交
    • X
      agp: Add device id for P4M900 to via-agp module · 32ddef98
      由 Xavier Bachelot 提交于 
      Signed-off-by: NDave Airlie <airlied@linux.ie>
      32ddef98
    • O
      [POWERPC] Fix undefined reference to device_power_up/resume · e120e8d0
      由 Olaf Hering 提交于 
      Current Linus tree fails to link on pmac32:

drivers/built-in.o: In function `pmac_wakeup_devices':
via-pmu.c:(.text+0x5bab4): undefined reference to `device_power_up'
via-pmu.c:(.text+0x5bb08): undefined reference to `device_resume'
drivers/built-in.o: In function `pmac_suspend_devices':
via-pmu.c:(.text+0x5c260): undefined reference to `device_power_down'
via-pmu.c:(.text+0x5c27c): undefined reference to `device_resume'
make[1]: *** [.tmp_vmlinux1] Error 1

changing CONFIG_PM > CONFIG_PM_SLEEP leads to:

drivers/built-in.o: In function `pmu_led_set':
via-pmu-led.c:(.text+0x5cdca): undefined reference to `pmu_sys_suspended'
via-pmu-led.c:(.text+0x5cdce): undefined reference to `pmu_sys_suspended'
drivers/built-in.o: In function `pmu_req_done':
via-pmu-led.c:(.text+0x5ce3e): undefined reference to `pmu_sys_suspended'
via-pmu-led.c:(.text+0x5ce42): undefined reference to `pmu_sys_suspended'
drivers/built-in.o: In function `adb_init':
(.init.text+0x4c5c): undefined reference to `pmu_register_sleep_notifier'
make[1]: *** [.tmp_vmlinux1] Error 1

So change even more places from PM to PM_SLEEP to allow linking.
Signed-off-by: NOlaf Hering <olaf@aepfle.de>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
      e120e8d0
  15. 24 8月, 2007 2 次提交
  17. 23 8月, 2007 12 次提交
  19. 22 8月, 2007 1 次提交
  21. 21 8月, 2007 2 次提交
    • B
      ide: add cable detection for early UDMA66 devices (take 3) · a5b7e70d
      由 Bartlomiej Zolnierkiewicz 提交于 
      * Move ide_in_drive_list() from ide-dma.c to ide-iops.c.

* Add ivb_list[] table for listening early UDMA66 devices which don't conform
  to ATA4 standard wrt cable detection (bit14 is zero, only bit13 is valid)
  and use only device side cable detection for them since host side cable
  detection may be unreliable.

* Add model "QUANTUM FIREBALLlct10 05" with firwmare "A03.0900" to the list
  (from Craig's bugreport).

v2:
* Improve kernel message basing on suggestion from Sergei.

v3:
* Don't print kernel message when no device side cable detection is done,
  plus some minor fixes.  (Noticed by Sergei)

Thanks to Craig for testing this patch.

Cc: Craig Block <chblock3@yahoo.com>
Acked-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      a5b7e70d
    • B
      ide: config_drive_for_dma() fixes · 1116fae5
      由 Bartlomiej Zolnierkiewicz 提交于 
      * Add DMA blacklist checking (->ide_dma_on check probably can go now).

* Add ->atapi_dma flag checking and remove no longer needed
  ns87415_ide_dma_check() from ns87415 host driver.

* Remove now needless __ide_dma_check() wrapper and symbol export.

* Check drive->autodma instead of hwif->autodma (there should be no changes in
  behavior as all users of config_drive_for_dma() set both ->autodma flags).
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>
      1116fae5
  23. 20 8月, 2007 1 次提交
  25. 18 8月, 2007 1 次提交
  27. 14 8月, 2007 1 次提交
  29. 13 8月, 2007 1 次提交
  31. 12 8月, 2007 2 次提交