linux-toradex.git/drivers, branch v2.6.32.58

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

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

hdpvr: fix race conditon during start of streaming

2012-03-04T17:49:21+00:00

commit afa159538af61f1a65d48927f4e949fe514fb4fc upstream.

status has to be set to STREAMING before the streaming worker is
queued. hdpvr_transmit_buffers() will exit immediately otherwise.

Reported-by: Joerg Desch 
Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Greg Kroah-Hartman

xhci: Fix encoding for HS bulk/control NAK rate.

2012-03-04T17:49:21+00:00

commit 340a3504fd39dad753ba908fb6f894ee81fc3ae2 upstream.

The xHCI 0.96 spec says that HS bulk and control endpoint NAK rate must
be encoded as an exponent of two number of microframes.  The endpoint
descriptor has the NAK rate encoded in number of microframes.  We were
just copying the value from the endpoint descriptor into the endpoint
context interval field, which was not correct.  This lead to the VIA
host rejecting the add of a bulk OUT endpoint from any USB 2.0 mass
storage device.

The fix is to use the correct encoding.  Refactor the code to convert
number of frames to an exponential number of microframes, and make sure
we convert the number of microframes in HS bulk and control endpoints to
an exponent.

This should be back ported to kernels as old as 2.6.31, that contain the
commit dfa49c4ad120a784ef1ff0717168aa79f55a483a "USB: xhci - fix math
in xhci_get_endpoint_interval"

Signed-off-by: Sarah Sharp 
Tested-by: Felipe Contreras 
Suggested-by: Andiry Xu 
Signed-off-by: Greg Kroah-Hartman

USB: Fix handoff when BIOS disables host PCI device.

2012-03-04T17:49:21+00:00

commit cab928ee1f221c9cc48d6615070fefe2e444384a upstream.

On some systems with an Intel Panther Point xHCI host controller, the
BIOS disables the xHCI PCI device during boot, and switches the xHCI
ports over to EHCI.  This allows the BIOS to access USB devices without
having xHCI support.

The downside is that the xHCI BIOS handoff mechanism will fail because
memory mapped I/O is not enabled for the disabled PCI device.
Jesse Barnes says this is expected behavior.  The PCI core will enable
BARs before quirks run, but it will leave it in an undefined state, and
it may not have memory mapped I/O enabled.

Make the generic USB quirk handler call pci_enable_device() to re-enable
MMIO, and call pci_disable_device() once the host-specific BIOS handoff
is finished.  This will balance the ref counts in the PCI core.  When
the PCI probe function is called, usb_hcd_pci_probe() will call
pci_enable_device() again.

This should be back ported to kernels as old as 2.6.31.  That was the
first kernel with xHCI support, and no one has complained about BIOS
handoffs failing due to memory mapped I/O being disabled on other hosts
(EHCI, UHCI, or OHCI).

Signed-off-by: Sarah Sharp 
Acked-by: Oliver Neukum 
Cc: Jesse Barnes 
Signed-off-by: Greg Kroah-Hartman

USB: Added Kamstrup VID/PIDs to cp210x serial driver.

2012-03-04T17:49:21+00:00

commit c6c1e4491dc8d1ed2509fa6aacffa7f34614fc38 upstream.

Signed-off-by: Bruno Thomsen 
Signed-off-by: Greg Kroah-Hartman