Fix the min and max bit lengths for AES-CTR (RFC3686) keys.
The number of bits in key spec is the key length (128/256)
plus 32 bits of nonce.
This change takes care of the "Invalid key length" errors
reported by setkey when specifying 288 bit keys for aes-ctr.
Signed-off-by: Tushar Gohad <tgohad@mvista.com> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Subject: [PATCH] Fix cdc-phonet build
Date: Saturday 23 Jul 2011
From: Chris Clayton <chris2553@googlemail.com>
To: linux-net@vger.kernel.org
cdc-phonet does not presently build on linux-3.0 because there is no entry for it in
drivers/net/Makefile. This patch adds that entry.
Signed-off-by: Chris Clayton <chris2553@googlemail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When a bond contains a device where one name is the subset of another
(eth1 and eth10, for example), one cannot properly set the primary
device or the currently active device.
This was reported and based on work by Takuma Umeya. I also verified
the problem and tested that this fix resolves it.
V2: A few did not like the the current code or my changes, so I
refactored bonding_store_primary and bonding_store_active_slave to be a
bit cleaner, dropped the use of strnicmp since we did not really need
the comparison to be case insensitive, and formatted the input string
from sysfs so a comparison to IFNAMSIZ could be used.
I also discovered an error in bonding_store_active_slave that would
modify bond->primary_slave rather than bond->curr_active_slave before
forcing the bonding driver to choose a new active slave.
V3: Actually sending the proper patch....
Signed-off-by: Andy Gospodarek <andy@greyhouse.net> Reported-by: Takuma Umeya <tumeya@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After the last patch, We are left in a state in which only drivers calling
ether_setup have IFF_TX_SKB_SHARING set (we assume that drivers touching real
hardware call ether_setup for their net_devices and don't hold any state in
their skbs. There are a handful of drivers that violate this assumption of
course, and need to be fixed up. This patch identifies those drivers, and marks
them as not being able to support the safe transmission of skbs by clearning the
IFF_TX_SKB_SHARING flag in priv_flags
Signed-off-by: Neil Horman <nhorman@tuxdriver.com> CC: Karsten Keil <isdn@linux-pingi.de> CC: "David S. Miller" <davem@davemloft.net> CC: Jay Vosburgh <fubar@us.ibm.com> CC: Andy Gospodarek <andy@greyhouse.net> CC: Patrick McHardy <kaber@trash.net> CC: Krzysztof Halasa <khc@pm.waw.pl> CC: "John W. Linville" <linville@tuxdriver.com> CC: Greg Kroah-Hartman <gregkh@suse.de> CC: Marcel Holtmann <marcel@holtmann.org> CC: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Pktgen attempts to transmit shared skbs to net devices, which can't be used by
some drivers as they keep state information in skbs. This patch adds a flag
marking drivers as being able to handle shared skbs in their tx path. Drivers
are defaulted to being unable to do so, but calling ether_setup enables this
flag, as 90% of the drivers calling ether_setup touch real hardware and can
handle shared skbs. A subsequent patch will audit drivers to ensure that the
flag is set properly
Signed-off-by: Neil Horman <nhorman@tuxdriver.com> Reported-by: Jiri Pirko <jpirko@redhat.com> CC: Robert Olsson <robert.olsson@its.uu.se> CC: Eric Dumazet <eric.dumazet@gmail.com> CC: Alexey Dobriyan <adobriyan@gmail.com> CC: David S. Miller <davem@davemloft.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If a device event generates gratuitous ARP messages, only primary
address is used for sending. This patch iterates through the whole
list. Tested with 2 IP addresses configuration on bonding interface.
Signed-off-by: Zoltan Kiss <schaman@sch.bme.hu> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
commit 8efa88540635 (sch_sfq: avoid giving spurious NET_XMIT_CN signals)
forgot to call qdisc_tree_decrease_qlen() to signal upper levels that a
packet (from another flow) was dropped, leading to various problems.
With help from Michal Soltys and Michal Pokrywka, who did a bisection.
Reported-by: Lucas Bocchi <lucas.bocchi@gmail.com> Reported-and-bisected-by: Michal Pokrywka <wolfmoon@o2.pl> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Michal Soltys <soltys@ziu.info> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Reported-by: Dave Jones <davej@redhat.com> Acked-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Hans Schillstrom <hans.schillstrom@ericsson.com> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
compare_keys and ip_route_input_common rely on
rt_oif for distinguishing of input and output routes
with same keys values. But sometimes the input route has
also same hash chain (keyed by iif != 0) with the output
routes (keyed by orig_oif=0). Problem visible if running
with small number of rhash_entries.
Fix them to use rt_route_iif instead. By this way
input route can not be returned to users that request
output route.
The patch fixes the ip_rt_bug errors that were
reported in ip_local_out context, mostly for 255.255.255.255
destinations.
Signed-off-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Because the ip fragment offset field counts 8-byte chunks, ip
fragments other than the last must contain a multiple of 8 bytes of
payload. ip_ufo_append_data wasn't respecting this constraint and,
depending on the MTU and ip option sizes, could create malformed
non-final fragments.
Google-Bug-Id: 5009328 Signed-off-by: Bill Sommerfeld <wsommerfeld@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fernando Gont reported current IPv6 fragment identification generation
was not secure, because using a very predictable system-wide generator,
allowing various attacks.
IPv4 uses inetpeer cache to address this problem and to get good
performance. We'll use this mechanism when IPv6 inetpeer is stable
enough in linux-3.1
For the time being, we use jhash on destination address to provide less
predictable identifications. Also remove a spinlock and use cmpxchg() to
get better SMP performance.
Reported-by: Fernando Gont <fernando@gont.com.ar> Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When creating the mixers for an USB audio device, the current code looks
at the host interface stored in mixer->chip->ctrl_if. Change this and
rather keep a local pointer to the interface that was given when
snd_usb_create_mixer() was called.
Cache handling in this driver is broken. The chip has 16-bit registers, yet the
register numbers also increase by 2 per register, i.e. there are only
even-numbered registers. The cache in this driver, though, simply increments
register numbers, so it does need some mapping as seen in
sgtl5000_restore_regs(), note the '>> 1':
That, of course, won't work with snd_soc_update_bits(). (Thus, we won't even
notice the missing register 0x1c in the default regs which shifted all follwing
registers to wrong values.) Noticed on the MX28EVK where enabling the regulators
simply locked up the chip.
Refactor the routines and use a properly sized default_regs array which matches
the register layout of the underlying chip, i.e. create a truly flat cache.
This also saves some code which should make up for the bigger array a little.
When soc-core will somewhen have another cache type which handles a step size,
this conversion will also ease the transition.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Tested-by: Dong Aisheng <b29396@freescale.com> Tested-by: Shawn Guo <shawn.guo@linaro.org> Acked-by: Liam Girdwood <lrg@ti.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Reported-and-Tested-by: Iain Arnell <iarnell@gmail.com> Reported-by: Patrick Oltmann <patrick.oltmann@gmx.net> Cc: Pavel Shilovsky <piastryyy@gmail.com> Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The loop around lookup_one_len doesn't handle the case where it might
return a negative dentry, which can cause an oops on the next pass
through the loop. Check for that and break out of the loop with an
error of -ENOENT if there is one.
if we failed on getting mid entry in cifs_call_async.
Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com> Signed-off-by: Steve French <sfrench@us.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
David S. Miller [Thu, 4 Aug 2011 03:50:44 +0000 (20:50 -0700)]
net: Compute protocol sequence numbers and fragment IDs using MD5.
Computers have become a lot faster since we compromised on the
partial MD4 hash which we use currently for performance reasons.
MD5 is a much safer choice, and is inline with both RFC1948 and
other ISS generators (OpenBSD, Solaris, etc.)
Furthermore, only having 24-bits of the sequence number be truly
unpredictable is a very serious limitation. So the periodic
regeneration and 8-bit counter have been removed. We compute and
use a full 32-bit sequence number.
For ipv6, DCCP was found to use a 32-bit truncated initial sequence
number (it needs 43-bits) and that is fixed here as well.
Reported-by: Dan Kaminsky <dan@doxpara.com> Tested-by: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drm_helper_hpd_irq_event queues another work proc to go and deliver
the user-space event, and that function also wants to hold the config
mutex, so we shouldn't hold the mutex across the
drm_helper_hpd_irq_event call.
Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Hotplug detection is a mode setting operation and must hold the
struct_mutex or risk colliding with other mode setting operations.
In particular, the display port hotplug function attempts to re-train
the link if the monitor is supposed to be running when plugged back
in. If that happens while mode setting is underway, the link will get
scrambled, leaving it in an inconsistent state.
This is a special case -- usually the driver mode setting entry points
are covered by the upper level DRM code, but in this case the function
is invoked as a work function not under the control of DRM.
Physically-addressed hardware status pages are initialized early in
the driver load process by i915_init_phys_hws. For UMS environments,
the ring structure is not initialized until the X server starts. At
that point, the entire ring structure is re-initialized with all new
values. Any values set in the ring structure (including
ring->status_page.page_addr) will be lost when the ring is
re-initialized.
This patch moves the initialization of the status_page.page_addr value
to intel_render_ring_init_dri.
Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Because of a typo, calling ioctl with DRM_IOCTL_I915_OVERLAY_PUT_IMAGE
is broken if the macro is used directly. When using libdrm the bug is
not hit, since libdrm handles the ioctl encoding internally.
The typo also leads to the .cmd and .cmd_drv fields of the drm_ioctl
structure for DRM_I915_OVERLAY_PUT_IMAGE having inconsistent content.
Signed-off-by: Ole Henrik Jahren <olehenja@alumni.ntnu.no> Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is broken. The total width of scanout would then be 1593 + 4 + 4,
or 1601, which is wider than the panel itself. The hardware very
dutifully implements this, and you end up with a black 45° diagonal from
the top-left corner to the bottom edge of the screen. It's a cool
effect and all, but not what you wanted. Similar things happen for the
letterbox case.
The problem is that you have an integer number of pixels, which means
it's usually impossible to upscale equally on both axes. 1360/768 is
1.7708, 1600/900 is 1.7777. Since we're constrained on the one axis,
the other one wants to come out as an even number of pixels (the panel
is almost certainly even on both axes, and the x/y offsets will be
applied on both sides). In the math above, if 'width' comes out even,
rounding down is correct; if it's odd, you'd rather round up. So just
increment width/height in those cases.
Tested on a Lenovo T500 (Ironlake).
Signed-off-by: Adam Jackson <ajax@redhat.com> Tested-By: Daniel Manrique <daniel.manrique@canonical.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=38851 Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Keith Packard <keithp@keithp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Log PCI subsystem vendor and subsystem device ID in addition to
PCI vendor and device ID during kernel mode initialisation. This helps
to better identify radeon devices of third-party vendors, e. g. for
bug analysis.
Tested for kernel 2.6.35, 2.6.38 and 3.0 on Asus M2A-VM HDMI board
Signed-off-by: Thomas Reim <reimth@gmail.com> Reviewed-by: Alex Deucher <alexdeucher@gmail.com> Acked-by: Stephen Michaels <Stephen.Micheals@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Some integrated ATI Radeon chipset implementations with add-on HDMI card
(e. g. Asus M2A-VM HDMI) indicate the availability of a DDC even
when the add-on card is not plugged in or HDMI is disabled in BIOS setup.
In this case, drm_get_edid() and drm_edid_block_valid() periodically
dump data and kernel errors into system log files and onto terminals.
For these connectors DDC probing is extended by a check for a correct
EDID header. Only in case a valid EDID header is also found, the
(HDMI or DVI) connector will be used by the Radeon driver. This prevents
the kernel driver from useless flooding of logs and terminal sessions with
EDID dumps and error messages.
This patch adds a flag 'requires_extended_probe' to the radeon_connector
structure. In function radeon_connector_needs_extended_probe() this flag
can be set on a chipset family/vendor/connector type specific basis.
In addition, function radeon_ddc_probe() has been adapted to perform
extended DDC probing if required by the connector's flag.
Requires function drm_edid_header_is_valid() in DRM module provided by
[PATCH] drm: Separate EDID Header Check from EDID Block Check.
Tested for kernel 2.6.35, 2.6.38 and 3.0 on Asus M2A-VM HDMI board
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=668196 BugLink: http://bugs.launchpad.net/bugs/7228066 Signed-off-by: Thomas Reim <reimth@gmail.com> Reviewed-by: Alex Deucher <alexdeucher@gmail.com> Acked-by: Stephen Michaels <Stephen.Micheals@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Provides function drm_edid_header_is_valid() for EDID header check
and replaces EDID header check part of function drm_edid_block_valid()
by a call of drm_edid_header_is_valid().
This is a prerequisite to extend DDC probing, e. g. in function
radeon_ddc_probe() for Radeon devices, by a central EDID header check.
Tested for kernel 2.6.35, 2.6.38 and 3.0
Signed-off-by: Thomas Reim <reimth@gmail.com> Reviewed-by: Alex Deucher <alexdeucher@gmail.com> Acked-by: Stephen Michaels <Stephen.Micheals@gmail.com> Signed-off-by: Dave Airlie <airlied@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Get the information about the VGA console hardware from Xen, and put
it into the form the bootloader normally generates, so that the rest
of the kernel can deal with VGA as usual.
[ Impact: make VGA console work in dom0 ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[v1: Rebased on 2.6.39]
[v2: Removed incorrect comments and fixed compile warnings] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The sendmmsg() introduced by commit 228e548e "net: Add sendmmsg socket system
call" is capable of sending to multiple different destination addresses.
SMACK is using destination's address for checking sendmsg() permission.
However, security_socket_sendmsg() is called for only once even if multiple
different destination addresses are passed to sendmmsg().
Therefore, we need to call security_socket_sendmsg() for each destination
address rather than only the first destination address.
Since calling security_socket_sendmsg() every time when only single destination
address was passed to sendmmsg() is a waste of time, omit calling
security_socket_sendmsg() unless destination address of previous datagram and
that of current datagram differs.
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
To limit the amount of time we can spend in sendmmsg, cap the
number of elements to UIO_MAXIOV (currently 1024).
For error handling an application using sendmmsg needs to retry at
the first unsent message, so capping is simpler and requires less
application logic than returning EINVAL.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
sendmmsg uses a similar error return strategy as recvmmsg but it
turns out to be a confusing way to communicate errors.
The current code stores the error code away and returns it on the next
sendmmsg call. This means a call with completely valid arguments could
get an error from a previous call.
Change things so we only return an error if no datagrams could be sent.
If less than the requested number of messages were sent, the application
must retry starting at the first failed one and if the problem is
persistent the error will be returned.
This matches the behaviour of other syscalls like read/write - it
is not an error if less than the requested number of elements are sent.
Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We receive many bug reports about system hang during suspend/resume
when ath9k driver is in use. Adrian Chadd remarked that this problem
happens on systems that have ASPM disabled.
To do not hit the bug, skip doing ->config_pci_powersave magic if PCIe
downstream port device, which ath9k device is connected to, has ASPM
disabled.
Patch should address:
https://bugzilla.kernel.org/show_bug.cgi?id=37462
https://bugzilla.kernel.org/show_bug.cgi?id=37082
https://bugzilla.redhat.com/show_bug.cgi?id=697157
however I did not receive confirmation about that, except from Camilo
Mesias, whose system stops hang regularly with this patch (but still
hangs from time to time, but this is probably some other bug).
Tested-by: Camilo Mesias <camilo@mesias.co.uk> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
With an uninitialized chainmask, the per-channel power will only contain
the power limits for a single chain instead of the combined tx power.
Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If settings of tx power was deferred during scan or changing channel we
have to setup them during commit rxon. Fix problem on 3945 (4965 already
has this fix).
Optimize code to apply tx settings only when tx power was actually
changed.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This driver uses information from the self member of the pci_bus struct to
get information regarding the bridge to which the PCIe device is attached.
Unfortunately, this member is not established on all architectures, which
leads to a kernel oops.
Skipping the entire block that uses the self member to determine the bridge
vendor will only affect RTL8192DE devices as that driver sets the ASPM support
flag differently when the bridge vendor is Intel. If the self member is
available, there is no functional change.
This patch fixes Bugzilla No. 40212.
Reported-by: Hubert Liao <liao.hubertt@gmail.com> Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We may call rt2x00queue_pause_queue(queue) with queue == NULL. Bug
was introduced by commit 62fe778412b36791b7897cfa139342906fbbf07b
"rt2x00: Fix stuck queue in tx failure case" .
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Acked-by: Gertjan van Wingerde <gwingerde@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We should clear skb->data not skb itself. Bug was introduced by:
commit 0b8004aa12d13ec750d102ba4082a95f0107c649 "rt2x00: Properly
reserve room for descriptors in skbs".
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Acked-by: Gertjan van Wingerde <gwingerde@gmail.com> Acked-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The return type of __atomic64_add_return of should be s64 or long, not
int. This fixes the atomic64 test failure that I previously reported.
Signed-off-by: John David Anglin <dave.anglin@nrc-cnrc.gc.ca> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Implements futex op support and makes futex cmpxchg atomic.
Tested on 64-bit SMP kernel running on 2 x PA8700s.
[jejb: checkpatch fixes] Signed-off-by: Carlos O'Donell <carlos@systemhalted.org> Tested-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: James Bottomley <JBottomley@Parallels.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
commit 7485d0d3758e8e6491a5c9468114e74dc050785d (futexes: Remove rw
parameter from get_futex_key()) in 2.6.33 fixed two problems: First, It
prevented a loop when encountering a ZERO_PAGE. Second, it fixed RW
MAP_PRIVATE futex operations by forcing the COW to occur by
unconditionally performing a write access get_user_pages_fast() to get
the page. The commit also introduced a user-mode regression in that it
broke futex operations on read-only memory maps. For example, this
breaks workloads that have one or more reader processes doing a
FUTEX_WAIT on a futex within a read only shared file mapping, and a
writer processes that has a writable mapping issuing the FUTEX_WAKE.
This fixes the regression for valid futex operations on RO mappings by
trying a RO get_user_pages_fast() when the RW get_user_pages_fast()
fails. This change makes it necessary to also check for invalid use
cases, such as anonymous RO mappings (which can never change) and the
ZERO_PAGE which the commit referenced above was written to address.
This patch does restore the original behavior with RO MAP_PRIVATE
mappings, which have inherent user-mode usage problems and don't really
make sense. With this patch performing a FUTEX_WAIT within a RO
MAP_PRIVATE mapping will be successfully woken provided another process
updates the region of the underlying mapped file. However, the mmap()
man page states that for a MAP_PRIVATE mapping:
It is unspecified whether changes made to the file after
the mmap() call are visible in the mapped region.
So user-mode users attempting to use futex operations on RO MAP_PRIVATE
mappings are depending on unspecified behavior. Additionally a
RO MAP_PRIVATE mapping could fail to wake up in the following case.
Thread-A: call futex(FUTEX_WAIT, memory-region-A).
get_futex_key() return inode based key.
sleep on the key
Thread-B: call mprotect(PROT_READ|PROT_WRITE, memory-region-A)
Thread-B: write memory-region-A.
COW happen. This process's memory-region-A become related
to new COWed private (ie PageAnon=1) page.
Thread-B: call futex(FUETX_WAKE, memory-region-A).
get_futex_key() return mm based key.
IOW, we fail to wake up Thread-A.
Once again doing something like this is just silly and users who do
something like this get what they deserve.
While RO MAP_PRIVATE mappings are nonsensical, checking for a private
mapping requires walking the vmas and was deemed too costly to avoid a
userspace hang.
This Patch is based on Peter Zijlstra's initial patch with modifications to
only allow RO mappings for futex operations that need VERIFY_READ access.
Reported-by: David Oliver <david@rgmadvisors.com> Signed-off-by: Shawn Bohrer <sbohrer@rgmadvisors.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Darren Hart <dvhart@linux.intel.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: peterz@infradead.org Cc: eric.dumazet@gmail.com Cc: zvonler@rgmadvisors.com Cc: hughd@google.com Link: http://lkml.kernel.org/r/1309450892-30676-1-git-send-email-sbohrer@rgmadvisors.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
arch/cris/arch-v10/kernel/irq.c:239: error: implicit declaration of function 'kgdb_init'
arch/cris/arch-v10/kernel/irq.c:240: error: implicit declaration of function 'breakpoint'
Declare these two functions.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
For normal kernel pages, CPU cache is synchronized by the dma layer.
However, this is not done for pages allocated with vmalloc. If we do I/O
to/from vmallocated pages, we must synchronize CPU cache explicitly.
Prior to doing I/O on vmallocated page we must call
flush_kernel_vmap_range to flush dirty cache on the virtual address.
After finished read we must call invalidate_kernel_vmap_range to
invalidate cache on the virtual address, so that accesses to the virtual
address return newly read data and not stale data from CPU cache.
This patch fixes metadata corruption on dm-snapshots on PA-RISC and
possibly other architectures with caches indexed by virtual address.
Fix the usage of mod_timer() and make the driver usable. mod_timer() must
be called with an absolute timeout in jiffies. The old implementation
used a relative timeout thus the hardware watchdog was never triggered.
Signed-off-by: David Engraf <david.engraf@sysgo.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Wim Van sebroeck <wim@iguana.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Reported-by: Wim Vander Schelden <wim@fixnum.org> Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com> Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
exit_mm() sets ->mm == NULL then it does mmput()->exit_mmap() which
frees the memory.
However select_bad_process() checks ->mm != NULL before TIF_MEMDIE,
so it continues to kill other tasks even if we have the oom-killed
task freeing its memory.
Change select_bad_process() to check ->mm after TIF_MEMDIE, but skip
the tasks which have already passed exit_notify() to ensure a zombie
with TIF_MEMDIE set can't block oom-killer. Alternatively we could
probably clear TIF_MEMDIE after exit_mmap().
AppArmor is masking the capabilities returned by capget against the
capabilities mask in the profile. This is wrong, in complain mode the
profile has effectively all capabilities, as the profile restrictions are
not being enforced, merely tested against to determine if an access is
known by the profile.
This can result in the wrong behavior of security conscience applications
like sshd which examine their capability set, and change their behavior
accordingly. In this case because of the masked capability set being
returned sshd fails due to DAC checks, even when the profile is in complain
mode.
Kernels affected: 2.6.36 - 3.0.
Signed-off-by: John Johansen <john.johansen@canonical.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The pointer returned from tracehook_tracer_task() is only valid inside
the rcu_read_lock. However the tracer pointer obtained is being passed
to aa_may_ptrace outside of the rcu_read_lock critical section.
Mover the aa_may_ptrace test into the rcu_read_lock critical section, to
fix this.
If a semaphore array is removed and in parallel a sleeping task is woken
up (signal or timeout, does not matter), then the woken up task does not
wait until wake_up_sem_queue_do() is completed. This will cause crashes,
because wake_up_sem_queue_do() will read from a stale pointer.
The fix is simple: Regardless of anything, always call get_queue_result().
This function waits until wake_up_sem_queue_do() has finished it's task.
Currently, the hvc_console_print() function drops console output if the
hvc backend's put_chars() returns 0. This patch changes this behavior
to allow a retry through returning -EAGAIN.
This change also affects the hvc_push() function. Both functions are
changed to handle -EAGAIN and to retry the put_chars() operation.
If a hvc backend returns -EAGAIN, the retry handling differs:
- hvc_console_print() spins to write the complete console output.
- hvc_push() behaves the same way as for returning 0.
Now hvc backends can indirectly control the way how console output is
handled through the hvc console layer.
Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
modpost error since the driver was merged in eea63e0e8a60d00485b47fb6e75d9aa2566b989b [SC26XX: New serial driver for
SC2681 uarts] in 2.6.25. Fixed by only allowing console support to be
enabled if the driver is builtin.
Commit 4539c24fe4f92c09ee668ef959d3e8180df619b9 "tty/serial: Add
explicit PORT_TEGRA type" introduced separate flags describing the need
for IER bits UUE and RTOIE. Both bits are required for the XSCALE port
type. While that patch updated uart_config[] as required, the auto-probing
code wasn't updated to set the RTOIE flag when an XSCALE port type was
detected. This caused such ports to stop working. This patch rectifies
that.
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Stephen Warren <swarren@nvidia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit 22a668d7c3ef ("memcg: fix behavior under memory.limit equals to
memsw.limit") introduced "memsw_is_minimum" flag, which becomes true
when mem_limit == memsw_limit. The flag is checked at the beginning of
reclaim, and "noswap" is set if the flag is true, because using swap is
meaningless in this case.
This works well in most cases, but when we try to shrink mem_limit,
which is the same as memsw_limit now, we might fail to shrink mem_limit
because swap doesn't used.
This patch fixes this behavior by:
- check MEM_CGROUP_RECLAIM_SHRINK at the begining of reclaim
- If it is set, don't set "noswap" flag even if memsw_is_minimum is true.
At the beginning of wiphy_update_regulatory() a check is performed
whether the request is to be ignored. Then the request is sent to
the driver nevertheless. This happens even if last_request points
to NULL, leading to a crash in the driver:
[<bf01d864>] (lbs_set_11d_domain_info+0x28/0x1e4 [libertas]) from [<c03b714c>] (wiphy_update_regulatory+0x4d0/0x4f4)
[<c03b714c>] (wiphy_update_regulatory+0x4d0/0x4f4) from [<c03b4008>] (wiphy_register+0x354/0x420)
[<c03b4008>] (wiphy_register+0x354/0x420) from [<bf01b17c>] (lbs_cfg_register+0x80/0x164 [libertas])
[<bf01b17c>] (lbs_cfg_register+0x80/0x164 [libertas]) from [<bf020e64>] (lbs_start_card+0x20/0x88 [libertas])
[<bf020e64>] (lbs_start_card+0x20/0x88 [libertas]) from [<bf02cbd8>] (if_sdio_probe+0x898/0x9c0 [libertas_sdio])
Fix this by returning early. Also remove the out: label as it is
not any longer needed.
Signed-off-by: Sven Neumann <s.neumann@raumfeld.com> Cc: linux-wireless@vger.kernel.org Cc: Johannes Berg <johannes@sipsolutions.net> Cc: Daniel Mack <daniel@zonque.org> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch (as1480) fixes a rather obscure bug in ehci-hcd. The
qh_update() routine needs to know the number and direction of the
endpoint corresponding to its QH argument. The number can be taken
directly from the QH data structure, but the direction isn't stored
there. The direction is taken instead from the first qTD linked to
the QH.
However, it turns out that for interrupt transfers, qh_update() gets
called before the qTDs are linked to the QH. As a result, qh_update()
computes a bogus direction value, which messes up the endpoint toggle
handling. Under the right combination of circumstances this causes
usb_reset_endpoint() not to work correctly, which causes packets to be
dropped and communications to fail.
Now, it's silly for the QH structure not to have direct access to all
the descriptor information for the corresponding endpoint. Ultimately
it may get a pointer to the usb_host_endpoint structure; for now,
adding a copy of the direction flag solves the immediate problem.
This allows the Spyder2 color-calibration system (a low-speed USB
device that sends all its interrupt data packets with the toggle set
to 0 and hance requires constant use of usb_reset_endpoint) to work
when connected through a high-speed hub. Thanks to Graeme Gill for
supplying the hardware that allowed me to track down this bug.
MAX4967 USB power supply chip we use on our boards signals over-current when
power is not enabled; once it's enabled, over-current signal returns to normal.
That unfortunately caused the endless stream of "over-current change on port"
messages. The EHCI root hub code reacts on every over-current signal change
with powering off the port -- such change event is generated the moment the
port power is enabled, so once enabled the power is immediately cut off.
I think we should only cut off power when we're seeing the active over-current
signal, so I'm adding such check to that code. I also think that the fact that
we've cut off the port power should be reflected in the result of GetPortStatus
request immediately, hence I'm adding a PORTSCn register readback after write...
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
FCS could be GSM0_SOF, so will break state machine...
[This byte isn't quoted in any way so a SOF here doesn't imply an error
occurred.]
Signed-off-by: Alek Du <alek.du@intel.com> Signed-off-by: Alan Cox <alan@linux.intel.com>
[Trivial but best backported once its in 3.1rc I think] Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If an inode's mode permits opening /proc/PID/io and the resulting file
descriptor is kept across execve() of a setuid or similar binary, the
ptrace_may_access() check tries to prevent using this fd against the
task with escalated privileges.
Unfortunately, there is a race in the check against execve(). If
execve() is processed after the ptrace check, but before the actual io
information gathering, io statistics will be gathered from the
privileged process. At least in theory this might lead to gathering
sensible information (like ssh/ftp password length) that wouldn't be
available otherwise.
Holding task->signal->cred_guard_mutex while gathering the io
information should protect against the race.
The order of locking is similar to the one inside of ptrace_attach():
first goes cred_guard_mutex, then lock_task_sighand().
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
If the directory contents change, then we have to accept that the
file->f_pos value may shrink if we do a 'search-by-cookie'. In that
case, we should turn off the loop detection and let the NFS client
try to recover.
The patch also fixes a second loop detection bug by ensuring
that after turning on the ctx->duped flag, we read at least one new
cookie into ctx->dir_cookie before attempting to match with
ctx->dup_cookie.
nfs_mark_return_delegation() is usually called without any locking, and
so it is not safe to dereference delegation->inode. Since the inode is
only used to discover the nfs_client anyway, it makes more sense to
have the callers pass a valid pointer to the nfs_server as a parameter.
Reported-by: Ian Kent <raven@themaw.net> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
After commit 3262c816a3d7fb1eaabce633caa317887ed549ae "[PATCH] knfsd:
split svc_serv into pools", svc_delete_xprt (then svc_delete_socket) no
longer removed its xpt_ready (then sk_ready) field from whatever list it
was on, noting that there was no point since the whole list was about to
be destroyed anyway.
That was mostly true, but forgot that a few svc_xprt_enqueue()'s might
still be hanging around playing with the about-to-be-destroyed list, and
could get themselves into trouble writing to freed memory if we left
this xprt on the list after freeing it.
(This is actually functionally identical to a patch made first by Ben
Greear, but with more comments.)
Cc: gnb@fmeh.org Reported-by: Ben Greear <greearb@candelatech.com> Tested-by: Ben Greear <greearb@candelatech.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Stateid's hold a read reference for a read open, a write reference for a
write open, and an additional one of each for each read+write open. The
latter wasn't getting put on a downgrade, so something like:
CLAIM_DELEGATE_CUR is used in response to a broken lease; allowing it
to break the lease and return EAGAIN leaves the client unable to make
progress in returning the delegation
nfs4_get_vfs_file() now takes struct nfsd4_open for access to the
claim type, and calls nfsd_open() with NFSD_MAY_NOT_BREAK_LEASE when
claim type is CLAIM_DELEGATE_CUR
Signed-off-by: Casey Bodley <cbodley@citi.umich.edu> Signed-off-by: J. Bruce Fields <bfields@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Kernel keyring keys containing eCryptfs authentication tokens should not
be write locked when calling out to ecryptfsd to wrap and unwrap file
encryption keys. The eCryptfs kernel code can not hold the key's write
lock because ecryptfsd needs to request the key after receiving such a
request from the kernel.
Without this fix, all file opens and creates will timeout and fail when
using the eCryptfs PKI infrastructure. This is not an issue when using
passphrase-based mount keys, which is the most widely deployed eCryptfs
configuration.
Block allocation is called from two places: ext3_get_blocks_handle() and
ext3_xattr_block_set(). These two callers are not necessarily synchronized
because xattr code holds only xattr_sem and i_mutex, and
ext3_get_blocks_handle() may hold only truncate_mutex when called from
writepage() path. Block reservation code does not expect two concurrent
allocations to happen to the same inode and thus assertions can be triggered
or reservation structure corruption can occur.
Fix the problem by taking truncate_mutex in xattr code to serialize
allocations.
CC: Sage Weil <sage@newdream.net> Reported-by: Fyodor Ustinov <ufm@ufm.su> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Upon corrupted inode or disk failures, we may fail after we already
allocate some blocks from the inode or take some blocks from the
inode's preallocation list, but before we successfully insert the
corresponding extent to the extent tree. In this case, we should free
any allocated blocks and discard the inode's preallocated blocks
because the entries in the inode's preallocation list may be in an
inconsistent state.
The current implementation of ext4_free_blocks() always calls
dquot_free_block This looks quite sensible in the most cases: blocks
to be freed are associated with inode and were accounted in quota and
i_blocks some time ago.
However, there is a case when blocks to free were not accounted by the
time calling ext4_free_blocks() yet:
1. delalloc is on, write_begin pre-allocated some space in quota
2. write-back happens, ext4 allocates some blocks in ext4_ext_map_blocks()
3. then ext4_ext_map_blocks() gets an error (e.g. ENOSPC) from
ext4_ext_insert_extent() and calls ext4_free_blocks().
In this scenario, ext4_free_blocks() calls dquot_free_block() who, in
turn, decrements i_blocks for blocks which were not accounted yet (due
to delalloc) After clean umount, e2fsck reports something like:
> Inode 21, i_blocks is 5080, should be 5128. Fix<y>?
because i_blocks was erroneously decremented as explained above.
The patch fixes the problem by passing the new flag
EXT4_FREE_BLOCKS_NO_QUOT_UPDATE to ext4_free_blocks(), to request
that the dquot_free_block() call be skipped.
: The system has many usb disks coming and going day to day, with their
: respective bdi's having min_ratio set to 1 when inserted. It works for
: some time until eventually min_ratio can no longer be set, even when the
: active set of bdi's seen in /sys/class/bdi/*/min_ratio doesn't add up to
: anywhere near 100.
:
: This then leads to an unrelated starvation problem caused by write-heavy
: fuse mounts being used atop the usb disks, a problem the min_ratio setting
: at the underlying devices bdi effectively prevents.
Fix this leakage by resetting the bdi min_ratio when unregistering the
BDI.
I haven't reproduced it myself but the fail scenario is that on such
machines (notably ARM and some embedded powerpc), if you manage to hit
that futex path on a writable page whose dirty bit has gone from the PTE,
you'll livelock inside the kernel from what I can tell.
It will go in a loop of trying the atomic access, failing, trying gup to
"fix it up", getting succcess from gup, go back to the atomic access,
failing again because dirty wasn't fixed etc...
So I think you essentially hang in the kernel.
The scenario is probably rare'ish because affected architecture are
embedded and tend to not swap much (if at all) so we probably rarely hit
the case where dirty is missing or young is missing, but I think Shan has
a piece of SW that can reliably reproduce it using a shared writable
mapping & fork or something like that.
On archs who use SW tracking of dirty & young, a page without dirty is
effectively mapped read-only and a page without young unaccessible in the
PTE.
Additionally, some architectures might lazily flush the TLB when relaxing
write protection (by doing only a local flush), and expect a fault to
invalidate the stale entry if it's still present on another processor.
The futex code assumes that if the "in_atomic()" access -EFAULT's, it can
"fix it up" by causing get_user_pages() which would then be equivalent to
taking the fault.
However that isn't the case. get_user_pages() will not call
handle_mm_fault() in the case where the PTE seems to have the right
permissions, regardless of the dirty and young state. It will eventually
update those bits ... in the struct page, but not in the PTE.
Additionally, it will not handle the lazy TLB flushing that can be
required by some architectures in the fault case.
Basically, gup is the wrong interface for the job. The patch provides a
more appropriate one which boils down to just calling handle_mm_fault()
since what we are trying to do is simulate a real page fault.
The futex code currently attempts to write to user memory within a
pagefault disabled section, and if that fails, tries to fix it up using
get_user_pages().
This doesn't work on archs where the dirty and young bits are maintained
by software, since they will gate access permission in the TLB, and will
not be updated by gup().
In addition, there's an expectation on some archs that a spurious write
fault triggers a local TLB flush, and that is missing from the picture as
well.
I decided that adding those "features" to gup() would be too much for this
already too complex function, and instead added a new simpler
fixup_user_fault() which is essentially a wrapper around handle_mm_fault()
which the futex code can call.
[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix some nits Darren saw, fiddle comment layout] Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reported-by: Shan Hai <haishan.bai@gmail.com> Tested-by: Shan Hai <haishan.bai@gmail.com> Cc: David Laight <David.Laight@ACULAB.COM> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Darren Hart <darren.hart@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As stated in drivers/mfd/cs5535-mfd.c, the mfd driver exposes the BARs
which then make the GPIO, MFGPT, ACPI, etc. all visible to the system.
So the dependencies of the MFGPT stuff have changed, and most people
expect Kconfig to bring in the necessary dependencies. Without them, the
module fails to load and most people don't understand why because the
details of the rewrite aren't captured anywhere most people who know to
look.
This dependency needs to be reflected in Kconfig.
Signed-off-by: Philip A. Prindeville <philipp@redfish-solutions.com> Acked-by: Alexandros C. Couloumbis <alex@ozo.com> Acked-by: Andres Salomon <dilinger@queued.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Most smartarrays will tolerate it, but some new ones don't.
Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com>
Note: this is a regression caused by commit 1ddd5049 Signed-off-by: Jens Axboe <jaxboe@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The function pci_enable_ari() may mistakenly set the downstream port
of a v1 PCIe switch in ARI Forwarding mode. This is a PCIe v2 feature,
and with an SR-IOV device on that switch port believing the switch above
is ARI capable it may attempt to use functions 8-255, translating into
invalid (non-zero) device numbers for that bus. This has been seen
to cause Completion Timeouts and general misbehaviour including hangs
and panics.
Acked-by: Don Dutile <ddutile@redhat.com> Tested-by: Don Dutile <ddutile@redhat.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
<linux/kernel.h> is needed for min_t. The old version
happened to work on x86 because <asm/unaligned.h>
indirectly includes <linux/kernel.h>, but it didn't
work on ARM.
<linux/kernel.h> includes <asm/byteorder.h> so it's
not necessary to include it explicitly anymore.
The "enable" file for the event system can be removed when a module
is unloaded and the event system only has events from that module.
As the event system nr_events count goes to zero, it may be freed
if its ref_count is also set to zero.
Like the "filter" file, the "enable" file may be opened by a task and
referenced later, after a module has been unloaded and the events for
that event system have been removed.
Although the "filter" file referenced the event system structure,
the "enable" file only references a pointer to the event system
name. Since the name is freed when the event system is removed,
it is possible that an access to the "enable" file may reference
a freed pointer.
Update the "enable" file to use the subsystem_open() routine that
the "filter" file uses, to keep a reference to the event system
structure while the "enable" file is opened.
Reported-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The event system is freed when its nr_events is set to zero. This happens
when a module created an event system and then later the module is
removed. Modules may share systems, so the system is allocated when
it is created and freed when the modules are unloaded and all the
events under the system are removed (nr_events set to zero).
The problem arises when a task opened the "filter" file for the
system. If the module is unloaded and it removed the last event for
that system, the system structure is freed. If the task that opened
the filter file accesses the "filter" file after the system has
been freed, the system will access an invalid pointer.
By adding a ref_count, and using it to keep track of what
is using the event system, we can free it after all users
are finished with the event system.
Reported-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Commit e360adbe29 ("irq_work: Add generic hardirq context
callbacks") fouled up the Alpha bit, not properly naming the
arch specific function that raises the 'self-IPI'.