linux-toradex.git, branch v2.6.32.58

Linux 2.6.32.58

2012-03-04T17:49:44+00:00

PM / Sleep: Fix read_unlock_usermodehelper() call.

2012-03-04T17:49:23+00:00

[ Upstream commit e4c89a508f4385a0cd8681c2749a2cd2fa476e40 ]

Commit b298d289
 "PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()"
added read_unlock_usermodehelper() but read_unlock_usermodehelper() is called
without read_lock_usermodehelper() when kmalloc() failed.

Signed-off-by: Tetsuo Handa 
Acked-by: Srivatsa S. Bhat 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Srivatsa S. Bhat 
Signed-off-by: Greg Kroah-Hartman

PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()

2012-03-04T17:49:23+00:00

[ Upstream commit b298d289c79211508f11cb50749b0d1d54eb244a ]

Commit a144c6a (PM: Print a warning if firmware is requested when tasks
are frozen) introduced usermodehelper_is_disabled() to warn and exit
immediately if firmware is requested when usermodehelpers are disabled.

However, it is racy. Consider the following scenario, currently used in
drivers/base/firmware_class.c:

...
if (usermodehelper_is_disabled())
        goto out;

/* Do actual work */
...

out:
        return err;

Nothing prevents someone from disabling usermodehelpers just after the check
in the 'if' condition, which means that it is quite possible to try doing the
"actual work" with usermodehelpers disabled, leading to undesirable
consequences.

In particular, this race condition in _request_firmware() causes task freezing
failures whenever suspend/hibernation is in progress because, it wrongly waits
to get the firmware/microcode image from userspace when actually the
usermodehelpers are disabled or userspace has been frozen.
Some of the example scenarios that cause freezing failures due to this race
are those that depend on userspace via request_firmware(), such as x86
microcode module initialization and microcode image reload.

Previous discussions about this issue can be found at:
http://thread.gmane.org/gmane.linux.kernel/1198291/focus=1200591

This patch adds proper synchronization to fix this issue.

It is to be noted that this patchset fixes the freezing failures but doesn't
remove the warnings. IOW, it does not attempt to add explicit synchronization
to x86 microcode driver to avoid requesting microcode image at inopportune
moments. Because, the warnings were introduced to highlight such cases, in the
first place. And we need not silence the warnings, since we take care of the
*real* problem (freezing failure) and hence, after that, the warnings are
pretty harmless anyway.

Signed-off-by: Srivatsa S. Bhat 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

firmware loader: allow builtin firmware load even if usermodehelper is disabled

2012-03-04T17:49:23+00:00

[ Upstream commit caca9510ff4e5d842c0589110243d60927836222 ]

In commit a144c6a6c924 ("PM: Print a warning if firmware is requested
when tasks are frozen") we not only printed a warning if somebody tried
to load the firmware when tasks are frozen - we also failed the load.

But that check was done before the check for built-in firmware, and then
when we disallowed usermode helpers during bootup (commit 288d5abec831:
"Boot up with usermodehelper disabled"), that actually means that
built-in modules can no longer load their firmware even if the firmware
is built in too.  Which used to work, and some people depended on it for
the R100 driver.

So move the test for usermodehelper_is_disabled() down, to after
checking the built-in firmware.

This should fix:

	https://bugzilla.kernel.org/show_bug.cgi?id=40952

Reported-by: James Cloos 
Bisected-by: Elimar Riesebieter 
Cc: Michel Dänzer 
Cc: Rafael Wysocki 
Cc: Valdis Kletnieks 
Signed-off-by: Linus Torvalds 
Signed-off-by: Srivatsa S. Bhat 
Signed-off-by: Greg Kroah-Hartman

PM: Print a warning if firmware is requested when tasks are frozen

2012-03-04T17:49:23+00:00

[ Upstream commit a144c6a6c924aa1da04dd77fb84b89927354fdff ]

Some drivers erroneously use request_firmware() from their ->resume()
(or ->thaw(), or ->restore()) callbacks, which is not going to work
unless the firmware has been built in.  This causes system resume to
stall until the firmware-loading timeout expires, which makes users
think that the resume has failed and reboot their machines
unnecessarily.  For this reason, make _request_firmware() print a
warning and return immediately with error code if it has been called
when tasks are frozen and it's impossible to start any new usermode
helpers.

Signed-off-by: Rafael J. Wysocki 
Acked-by: Greg Kroah-Hartman 
Reviewed-by: Valdis Kletnieks 
Signed-off-by: Srivatsa S. Bhat 
Signed-off-by: Greg Kroah-Hartman

compat: fix compile breakage on s390

2012-03-04T17:49:22+00:00

commit 048cd4e51d24ebf7f3552226d03c769d6ad91658 upstream.

The new is_compat_task() define for the !COMPAT case in
include/linux/compat.h conflicts with a similar define in
arch/s390/include/asm/compat.h.

This is the minimal patch which fixes the build issues.

Signed-off-by: Heiko Carstens 
Signed-off-by: Linus Torvalds 
Cc: Jonathan Nieder 
Signed-off-by: Greg Kroah-Hartman

Fix autofs compile without CONFIG_COMPAT

2012-03-04T17:49:22+00:00

commit 3c761ea05a8900a907f32b628611873f6bef24b2 upstream.

The autofs compat handling fix caused a compile failure when
CONFIG_COMPAT isn't defined.

Instead of adding random #ifdef'fery in autofs, let's just make the
compat helpers earlier to use: without CONFIG_COMPAT, is_compat_task()
just hardcodes to zero.

We could probably do something similar for a number of other cases where
we have #ifdef's in code, but this is the low-hanging fruit.

Reported-and-tested-by: Andreas Schwab 
Signed-off-by: Linus Torvalds 
Cc: Jonathan Nieder 
Signed-off-by: Greg Kroah-Hartman

autofs: work around unhappy compat problem on x86-64

2012-03-04T17:49:22+00:00

commit a32744d4abae24572eff7269bc17895c41bd0085 upstream.

When the autofs protocol version 5 packet type was added in commit
5c0a32fc2cd0 ("autofs4: add new packet type for v5 communications"), it
obvously tried quite hard to be word-size agnostic, and uses explicitly
sized fields that are all correctly aligned.

However, with the final "char name[NAME_MAX+1]" array at the end, the
actual size of the structure ends up being not very well defined:
because the struct isn't marked 'packed', doing a "sizeof()" on it will
align the size of the struct up to the biggest alignment of the members
it has.

And despite all the members being the same, the alignment of them is
different: a "__u64" has 4-byte alignment on x86-32, but native 8-byte
alignment on x86-64.  And while 'NAME_MAX+1' ends up being a nice round
number (256), the name[] array starts out a 4-byte aligned.

End result: the "packed" size of the structure is 300 bytes: 4-byte, but
not 8-byte aligned.

As a result, despite all the fields being in the same place on all
architectures, sizeof() will round up that size to 304 bytes on
architectures that have 8-byte alignment for u64.

Note that this is *not* a problem for 32-bit compat mode on POWER, since
there __u64 is 8-byte aligned even in 32-bit mode.  But on x86, 32-bit
and 64-bit alignment is different for 64-bit entities, and as a result
the structure that has exactly the same layout has different sizes.

So on x86-64, but no other architecture, we will just subtract 4 from
the size of the structure when running in a compat task.  That way we
will write the properly sized packet that user mode expects.

Not pretty.  Sadly, this very subtle, and unnecessary, size difference
has been encoded in user space that wants to read packets of *exactly*
the right size, and will refuse to touch anything else.

Reported-and-tested-by: Thomas Meyer 
Signed-off-by: Ian Kent 
Signed-off-by: Linus Torvalds 
Cc: Jonathan Nieder 
Signed-off-by: Greg Kroah-Hartman

cdrom: use copy_to_user() without the underscores

2012-03-04T17:49:22+00:00

commit 822bfa51ce44f2c63c300fdb76dc99c4d5a5ca9f upstream.

"nframes" comes from the user and "nframes * CD_FRAMESIZE_RAW" can wrap
on 32 bit systems.  That would have been ok if we used the same wrapped
value for the copy, but we use a shifted value.  We should just use the
checked version of copy_to_user() because it's not going to make a
difference to the speed.

Signed-off-by: Dan Carpenter 
Signed-off-by: Jens Axboe 
Signed-off-by: Greg Kroah-Hartman

eCryptfs: Clear i_nlink in rmdir

2012-03-04T17:49:22+00:00

commit 07850552b92b3637fa56767b5e460b4238014447 upstream.

eCryptfs wasn't clearing the eCryptfs inode's i_nlink after a successful
vfs_rmdir() on the lower directory. This resulted in the inode evict and
destroy paths to be missed.

https://bugs.launchpad.net/ecryptfs/+bug/723518

Signed-off-by: Tyler Hicks 
Signed-off-by: Colin King 
Signed-off-by: Tim Gardner 
Signed-off-by: Greg Kroah-Hartman