linux-toradex.git/drivers/char, branch v2.6.33.5

tty: Fix unbalanced BKL handling in error path

2010-05-26T21:32:07+00:00

commit 77945febbe60a69e9dcab7f49d33a1aa1e436973 upstream.

Arnd noted:

After the "retry_open:" label, we first get the tty_mutex
and then the BKL. However a the end of tty_open, we jump
back to retry_open with the BKL still held. If we run into
this case, the tty_open function will be left with the BKL
still held.

Signed-off-by: Alan Cox 
Acked-by: Arnd Bergmann 
Signed-off-by: Greg Kroah-Hartman

x86, k8 nb: Fix boot crash: enable k8_northbridges unconditionally on AMD systems

2010-05-12T22:02:45+00:00

commit 0e152cd7c16832bd5cadee0c2e41d9959bc9b6f9 upstream.

de957628ce7c84764ff41331111036b3ae5bad0f changed setting of the
x86_init.iommu.iommu_init function ptr only when GART IOMMU is
found.

One side effect of it is that num_k8_northbridges
is not initialized anymore if not explicitly
called. This resulted in uninitialized pointers in
,
for example, which uses the num_k8_northbridges thing through
node_to_k8_nb_misc().

Fix that through an initcall that runs right after the PCI
subsystem and does all the scanning. Then, remove initialization
in gart_iommu_init() which is a rootfs_initcall and we're
running before that.

What is more, since num_k8_northbridges is being used in other
places beside GART IOMMU, include it whenever we add AMD CPU
support. The previous dependency chain in kconfig contained

K8_NB depends on AGP_AMD64|GART_IOMMU

which was clearly incorrect. The more natural way in terms of
hardware dependency should be

AGP_AMD64|GART_IOMMU depends on K8_NB depends on CPU_SUP_AMD &&
PCI. Make it so Number One!

Signed-off-by: Borislav Petkov 
Cc: FUJITA Tomonori 
Cc: Joerg Roedel 
LKML-Reference: <20100312144303.GA29262@aftab>
Signed-off-by: Ingo Molnar 
Tested-by: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

intel-agp: Switch to wbinvd_on_all_cpus

2010-04-26T14:47:56+00:00

commit 48a719c238bcbb72d6da79de9c5b3b93ab472107 upstream.

Simplify if-statement while at it.

[ hpa: we need to #include  ]

Cc: Dave Jones 
Cc: David Airlie 
Signed-off-by: Borislav Petkov 
LKML-Reference: <1264172467-25155-3-git-send-email-bp@amd64.org>
Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

raw: fsync method is now required

2010-04-26T14:47:49+00:00

commit 55ab3a1ff843e3f0e24d2da44e71bffa5d853010 upstream.

Commit 148f948ba877f4d3cdef036b1ff6d9f68986706a (vfs: Introduce new
helpers for syncing after writing to O_SYNC file or IS_SYNC inode) broke
the raw driver.

We now call through generic_file_aio_write -> generic_write_sync ->
vfs_fsync_range.  vfs_fsync_range has:

        if (!fop || !fop->fsync) {
                ret = -EINVAL;
                goto out;
        }

But drivers/char/raw.c doesn't set an fsync method.

We have two options: fix it or remove the raw driver completely.  I'm
happy to do either, the fact this has been broken for so long suggests it
is rarely used.

The patch below adds an fsync method to the raw driver.  My knowledge of
the block layer is pretty sketchy so this could do with a once over.

If we instead decide to remove the raw driver, this patch might still be
useful as a backport to 2.6.33 and 2.6.32.

Signed-off-by: Anton Blanchard 
Reviewed-by: Jan Kara 
Cc: Christoph Hellwig 
Cc: Alexander Viro 
Cc: Jens Axboe 
Reviewed-by: Jeff Moyer 
Tested-by: Jeff Moyer 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

tty: release_one_tty() forgets to put pids

2010-04-26T14:47:49+00:00

commit 6da8d866d0d39e9509ff826660f6a86a6757c966 upstream.

release_one_tty(tty) can be called when tty still has a reference
to pgrp/session. In this case we leak the pid.

Signed-off-by: Oleg Nesterov 
Reported-by: Catalin Marinas 
Reported-and-tested-by: Tetsuo Handa 
Acked-by: Linus Torvalds 
Acked-by: Eric W. Biederman 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

tty: Keep the default buffering to sub-page units

2010-04-01T23:01:35+00:00

commit d9661adfb8e53a7647360140af3b92284cbe52d4 upstream.

We allocate during interrupts so while our buffering is normally diced up
small anyway on some hardware at speed we can pressure the VM excessively
for page pairs. We don't really need big buffers to be linear so don't try
so hard.

In order to make this work well we will tidy up excess callers to request_room,
which cannot itself enforce this break up.

Signed-off-by: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

tty: Fix the ldisc hangup race

2010-03-15T16:06:26+00:00

commit 638b9648ab51c9c549ff5735d3de519ef6199df3 upstream.

This was noticed by Matthias Urlichs and he proposed a fix. This patch
does the fixing a different way to avoid introducing several new race
conditions into the code.

The problem case is TTY_DRIVER_RESET_TERMIOS = 0. In that case while we
abort the ldisc change, the hangup processing has not cleaned up and restarted
the ldisc either.

We can't restart the ldisc stuff in the set_ldisc as we don't know what
the hangup did and may touch stuff we shouldn't as we are no longer
supposed to influence the tty at that point in case it has been re-opened
before we get rescheduled.

Instead do it the simple way. Always re-init the ldisc on the hangup, but
use TTY_DRIVER_RESET_TERMIOS to indicate that we should force N_TTY.

Signed-off-by: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

2010-02-11T22:01:10+00:00

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, apic: Don't use logical-flat mode when CPU hotplug may exceed 8 CPUs
  x86-32: Make AT_VECTOR_SIZE_ARCH=2
  x86/agp: Fix amd64-agp module initialization regression
  x86, doc: Fix minor spelling error in arch/x86/mm/gup.c

tpm_infineon: fix suspend/resume handler for pnp_driver

2010-02-11T21:59:42+00:00

When suspending, tpm_infineon calls the generic suspend function of the
TPM framework.  However, the TPM framework does not return and the system
hangs upon suspend.  When sending the necessary command "TPM_SaveState"
directly within the driver, suspending and resuming works fine.

Signed-off-by: Marcel Selhorst 
Cc: OGAWA Hirofumi 
Cc: Debora Velarde 
Cc: Rajiv Andrade 
Cc: 		[2.6.32.x]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Fix race in tty_fasync() properly

2010-02-07T18:26:01+00:00

This reverts commit 703625118069 ("tty: fix race in tty_fasync") and
commit b04da8bfdfbb ("fnctl: f_modown should call write_lock_irqsave/
restore") that tried to fix up some of the fallout but was incomplete.

It turns out that we really cannot hold 'tty->ctrl_lock' over calling
__f_setown, because not only did that cause problems with interrupt
disables (which the second commit fixed), it also causes a potential
ABBA deadlock due to lock ordering.

Thanks to Tetsuo Handa for following up on the issue, and running
lockdep to show the problem.  It goes roughly like this:

 - f_getown gets filp->f_owner.lock for reading without interrupts
   disabled, so an interrupt that happens while that lock is held can
   cause a lockdep chain from f_owner.lock -> sighand->siglock.

 - at the same time, the tty->ctrl_lock -> f_owner.lock chain that
   commit 703625118069 introduced, together with the pre-existing
   sighand->siglock -> tty->ctrl_lock chain means that we have a lock
   dependency the other way too.

So instead of extending tty->ctrl_lock over the whole __f_setown() call,
we now just take a reference to the 'pid' structure while holding the
lock, and then release it after having done the __f_setown.  That still
guarantees that 'struct pid' won't go away from under us, which is all
we really ever needed.

Reported-and-tested-by: Tetsuo Handa 
Acked-by: Greg Kroah-Hartman 
Acked-by: Américo Wang 
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds