Since we just matched sme->{ssid,ssid_len} to
pnetwork->network.Ssid.{ssid,ssid_len} we can simplify the copy and
move it to just before the call to rtw_set_ssid().
Jes Sorensen [Mon, 9 Jun 2014 13:16:17 +0000 (15:16 +0200)]
staging: rtl8723au: Let cfg80211 handle public action management frames
The driver shouldn't be dealing with public action management frames.
Let these go directly to the cfg80211 layer which can defer them to
userland if needed.
Jes Sorensen [Mon, 9 Jun 2014 13:16:16 +0000 (15:16 +0200)]
staging: rtl8723au: Do not xmit BSS Coexistence management action frames
The driver should not be issuing BSS Coexistence management action
frames when scanning. This isn't required by the spec, and if needed,
these should come from wpa_s instead.
Jes Sorensen [Mon, 9 Jun 2014 13:16:15 +0000 (15:16 +0200)]
staging: rtl8723au: issue_action_BSSCoexistPacket(): Use struct ieee80211_mgmt
This gets rid of the rtw_set_fixed_ie23a() usage here. Note that this
abuses ieee80211_mgmt.u.action.u.chan_switch for now, since the
correct defines are currently missing, and this one matches.
Need to fix up the definitions in ieee80211.h and afterwards fix it up
here.
Yet another duplicate version of struct ieee80211_ht_operation
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
introduced a bad error, applying the wrong value as the mask when
determining the location of the 40MHz channel, effectively making it
always determining it as not present. This caused hangs and delays
when running in 40MHz channel mode.
Jes Sorensen [Sat, 31 May 2014 16:05:14 +0000 (18:05 +0200)]
staging: rtl8723au: Don't carry ht_cap_info and ht_param in struct wlan_bcn_info
These were just stored to check whether the beacon info had changed
and print a debug message in this case. If we ever need this again, we
can determine this change differently.
Jes Sorensen [Sat, 31 May 2014 16:05:10 +0000 (18:05 +0200)]
staging: rtl8723au: Use struct ieee80211_mcs_info to describe MCS information
The original RTL code defined the MCS information as a 16 byte array
and blindly applied it's masking over the full array, ignoring the
fact that only the first 10 bytes describe the rx_mask and the rest
are different fields.
1) Fix checksumming regressions, from Tom Herbert.
2) Undo unintentional permissions changes for SCTP rto_alpha and
rto_beta sysfs knobs, from Denial Borkmann.
3) VXLAN, like other IP tunnels, should advertize it's encapsulation
size using dev->needed_headroom instead of dev->hard_header_len.
From Cong Wang.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
net: sctp: fix permissions for rto_alpha and rto_beta knobs
vxlan: Checksum fixes
net: add skb_pop_rcv_encapsulation
udp: call __skb_checksum_complete when doing full checksum
net: Fix save software checksum complete
net: Fix GSO constants to match NETIF flags
udp: ipv4: do not waste time in __udp4_lib_mcast_demux_lookup
vxlan: use dev->needed_headroom instead of dev->hard_header_len
MAINTAINERS: update cxgb4 maintainer
Linus Torvalds [Mon, 16 Jun 2014 02:02:20 +0000 (16:02 -1000)]
Merge tag 'clk-for-linus-3.16-part2' of git://git.linaro.org/people/mike.turquette/linux
Pull more clock framework updates from Mike Turquette:
"This contains the second half the of the clk changes for 3.16.
They are simply fixes and code refactoring for the OMAP clock drivers.
The sunxi clock driver changes include splitting out the one
mega-driver into several smaller pieces and adding support for the A31
SoC clocks"
* tag 'clk-for-linus-3.16-part2' of git://git.linaro.org/people/mike.turquette/linux: (25 commits)
clk: sunxi: document PRCM clock compatible strings
clk: sunxi: add PRCM (Power/Reset/Clock Management) clks support
clk: sun6i: Protect SDRAM gating bit
clk: sun6i: Protect CPU clock
clk: sunxi: Rework clock protection code
clk: sunxi: Move the GMAC clock to a file of its own
clk: sunxi: Move the 24M oscillator to a file of its own
clk: sunxi: Remove calls to clk_put
clk: sunxi: document new A31 USB clock compatible
clk: sunxi: Implement A31 USB clock
ARM: dts: OMAP5/DRA7: use omap5-mpu-dpll-clock capable of dealing with higher frequencies
CLK: TI: dpll: support OMAP5 MPU DPLL that need special handling for higher frequencies
ARM: OMAP5+: dpll: support Duty Cycle Correction(DCC)
CLK: TI: clk-54xx: Set the rate for dpll_abe_m2x2_ck
CLK: TI: Driver for DRA7 ATL (Audio Tracking Logic)
dt:/bindings: DRA7 ATL (Audio Tracking Logic) clock bindings
ARM: dts: dra7xx-clocks: Correct name for atl clkin3 clock
CLK: TI: gate: add composite interface clock to OMAP2 only build
ARM: OMAP2: clock: add DT boot support for cpufreq_ck
CLK: TI: OMAP2: add clock init support
...
Pull NVMe update from Matthew Wilcox:
"Mostly bugfixes again for the NVMe driver. I'd like to call out the
exported tracepoint in the block layer; I believe Keith has cleared
this with Jens.
We've had a few reports from people who're really pounding on NVMe
devices at scale, hence the timeout changes (and new module
parameters), hotplug cpu deadlock, tracepoints, and minor performance
tweaks"
[ Jens hadn't seen that tracepoint thing, but is ok with it - it will
end up going away when mq conversion happens ]
* git://git.infradead.org/users/willy/linux-nvme: (22 commits)
NVMe: Fix START_STOP_UNIT Scsi->NVMe translation.
NVMe: Use Log Page constants in SCSI emulation
NVMe: Define Log Page constants
NVMe: Fix hot cpu notification dead lock
NVMe: Rename io_timeout to nvme_io_timeout
NVMe: Use last bytes of f/w rev SCSI Inquiry
NVMe: Adhere to request queue block accounting enable/disable
NVMe: Fix nvme get/put queue semantics
NVMe: Delete NVME_GET_FEAT_TEMP_THRESH
NVMe: Make admin timeout a module parameter
NVMe: Make iod bio timeout a parameter
NVMe: Prevent possible NULL pointer dereference
NVMe: Fix the buffer size passed in GetLogPage(CDW10.NUMD)
NVMe: Update data structures for NVMe 1.2
NVMe: Enable BUILD_BUG_ON checks
NVMe: Update namespace and controller identify structures to the 1.1a spec
NVMe: Flush with data support
NVMe: Configure support for block flush
NVMe: Add tracepoints
NVMe: Protect against badly formatted CQEs
...
Daniel Borkmann [Sat, 14 Jun 2014 22:59:14 +0000 (00:59 +0200)]
net: sctp: fix permissions for rto_alpha and rto_beta knobs
Commit 3fd091e73b81 ("[SCTP]: Remove multiple levels of msecs
to jiffies conversions.") has silently changed permissions for
rto_alpha and rto_beta knobs from 0644 to 0444. The purpose of
this was to discourage users from tweaking rto_alpha and
rto_beta knobs in production environments since they are key
to correctly compute rtt/srtt.
RFC4960 under section 6.3.1. RTO Calculation says regarding
rto_alpha and rto_beta under rule C3 and C4:
[...]
C3) When a new RTT measurement R' is made, set
Note: The value of SRTT used in the update to RTTVAR
is its value before updating SRTT itself using the
second assignment. After the computation, update
RTO <- SRTT + 4 * RTTVAR.
C4) When data is in flight and when allowed by rule C5
below, a new RTT measurement MUST be made each round
trip. Furthermore, new RTT measurements SHOULD be
made no more than once per round trip for a given
destination transport address. There are two reasons
for this recommendation: First, it appears that
measuring more frequently often does not in practice
yield any significant benefit [ALLMAN99]; second,
if measurements are made more often, then the values
of RTO.Alpha and RTO.Beta in rule C3 above should be
adjusted so that SRTT and RTTVAR still adjust to
changes at roughly the same rate (in terms of how many
round trips it takes them to reflect new values) as
they would if making only one measurement per
round-trip and using RTO.Alpha and RTO.Beta as given
in rule C3. However, the exact nature of these
adjustments remains a research issue.
[...]
While it is discouraged to adjust rto_alpha and rto_beta
and not further specified how to adjust them, the RFC also
doesn't explicitly forbid it, but rather gives a RECOMMENDED
default value (rto_alpha=3, rto_beta=2). We have a couple
of users relying on the old permissions before they got
changed. That said, if someone really has the urge to adjust
them, we could allow it with a warning in the log.
Fixes: 3fd091e73b81 ("[SCTP]: Remove multiple levels of msecs to jiffies conversions.") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Cc: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Sun, 15 Jun 2014 08:00:56 +0000 (01:00 -0700)]
Merge branch 'csum_fixes'
Tom Herbert says:
====================
Fixes related to some recent checksum modifications.
- Fix GSO constants to match NETIF flags
- Fix logic in saving checksum complete in __skb_checksum_complete
- Call __skb_checksum_complete from UDP if we are checksumming over
whole packet in order to save checksum.
- Fixes to VXLAN to work correctly with checksum complete
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert [Sun, 15 Jun 2014 06:24:28 +0000 (23:24 -0700)]
net: add skb_pop_rcv_encapsulation
This function is used by UDP encapsulation protocols in RX when
crossing encapsulation boundary. If ip_summed is set to
CHECKSUM_UNNECESSARY and encapsulation is not set, change to
CHECKSUM_NONE since the checksum has not been validated within the
encapsulation. Clears csum_valid by the same rationale.
Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert [Sun, 15 Jun 2014 06:24:20 +0000 (23:24 -0700)]
udp: call __skb_checksum_complete when doing full checksum
In __udp_lib_checksum_complete check if checksum is being done over all
the data (len is equal to skb->len) and if it is call
__skb_checksum_complete instead of __skb_checksum_complete_head. This
allows checksum to be saved in checksum complete.
Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert [Sun, 15 Jun 2014 06:24:03 +0000 (23:24 -0700)]
net: Fix save software checksum complete
Geert reported issues regarding checksum complete and UDP.
The logic introduced in commit 7e3cead5172927732f51fde
("net: Save software checksum complete") is not correct.
This patch:
1) Restores code in __skb_checksum_complete_header except for setting
CHECKSUM_UNNECESSARY. This function may be calculating checksum on
something less than skb->len.
2) Adds saving checksum to __skb_checksum_complete. The full packet
checksum 0..skb->len is calculated without adding in pseudo header.
This value is saved in skb->csum and then the pseudo header is added
to that to derive the checksum for validation.
3) In both __skb_checksum_complete_header and __skb_checksum_complete,
set skb->csum_valid to whether checksum of zero was computed. This
allows skb_csum_unnecessary to return true without changing to
CHECKSUM_UNNECESSARY which was done previously.
4) Copy new csum related bits in __copy_skb_header.
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert [Sun, 15 Jun 2014 06:23:52 +0000 (23:23 -0700)]
net: Fix GSO constants to match NETIF flags
Joseph Gasparakis reported that VXLAN GSO offload stopped working with
i40e device after recent UDP changes. The problem is that the
SKB_GSO_* bits are out of sync with the corresponding NETIF flags. This
patch fixes that. Also, we add BUILD_BUG_ONs in net_gso_ok for several
GSO constants that were missing to avoid the problem in the future.
Reported-by: Joseph Gasparakis <joseph.gasparakis@intel.com> Signed-off-by: Tom Herbert <therbert@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Sun, 15 Jun 2014 00:49:48 +0000 (19:49 -0500)]
Merge tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull more SCSI updates from James Bottomley:
"This is just a couple of drivers (hpsa and lpfc) that got left out for
further testing in linux-next. We also have one fix to a prior
submission (qla2xxx sparse)"
* tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (36 commits)
qla2xxx: fix sparse warnings introduced by previous target mode t10-dif patch
lpfc: Update lpfc version to driver version 10.2.8001.0
lpfc: Fix ExpressLane priority setup
lpfc: mark old devices as obsolete
lpfc: Fix for initializing RRQ bitmap
lpfc: Fix for cleaning up stale ring flag and sp_queue_event entries
lpfc: Update lpfc version to driver version 10.2.8000.0
lpfc: Update Copyright on changed files from 8.3.45 patches
lpfc: Update Copyright on changed files
lpfc: Fixed locking for scsi task management commands
lpfc: Convert runtime references to old xlane cfg param to fof cfg param
lpfc: Fix FW dump using sysfs
lpfc: Fix SLI4 s abort loop to process all FCP rings and under ring_lock
lpfc: Fixed kernel panic in lpfc_abort_handler
lpfc: Fix locking for postbufq when freeing
lpfc: Fix locking for lpfc_hba_down_post
lpfc: Fix dynamic transitions of FirstBurst from on to off
hpsa: fix handling of hpsa_volume_offline return value
hpsa: return -ENOMEM not -1 on kzalloc failure in hpsa_get_device_id
hpsa: remove messages about volume status VPD inquiry page not supported
...
Linus Torvalds [Sun, 15 Jun 2014 00:48:43 +0000 (19:48 -0500)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull more btrfs updates from Chris Mason:
"This has a few fixes since our last pull and a new ioctl for doing
btree searches from userland. It's very similar to the existing
ioctl, but lets us return larger items back down to the app"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: fix error handling in create_pending_snapshot
btrfs: fix use of uninit "ret" in end_extent_writepage()
btrfs: free ulist in qgroup_shared_accounting() error path
Btrfs: fix qgroups sanity test crash or hang
btrfs: prevent RCU warning when dereferencing radix tree slot
Btrfs: fix unfinished readahead thread for raid5/6 degraded mounting
btrfs: new ioctl TREE_SEARCH_V2
btrfs: tree_search, search_ioctl: direct copy to userspace
btrfs: new function read_extent_buffer_to_user
btrfs: tree_search, copy_to_sk: return needed size on EOVERFLOW
btrfs: tree_search, copy_to_sk: return EOVERFLOW for too small buffer
btrfs: tree_search, search_ioctl: accept varying buffer
btrfs: tree_search: eliminate redundant nr_items check
Al Viro [Sat, 14 Jun 2014 06:12:41 +0000 (07:12 +0100)]
fix __swap_writepage() compile failure on old gcc versions
Tetsuo Handa wrote:
"Commit 62a8067a7f35 ("bio_vec-backed iov_iter") introduced an unnamed
union inside a struct which gcc-4.4.7 cannot handle. Name the unnamed
union as u in order to fix build failure"
Let's do this instead: there is only one place in the entire tree that
steps into this breakage. Anon structs and unions work in older gcc
versions; as the matter of fact, we have those in the tree - see e.g.
struct ieee80211_tx_info in include/net/mac80211.h
What doesn't work is handling their initializers:
struct {
int a;
union {
int b;
char c;
};
} x[2] = {{.a = 1, .c = 'a'}, {.a = 0, .b = 1}};
is the obvious syntax for initializer, perfectly fine for C11 and
handled correctly by gcc-4.7 or later.
Earlier versions, though, break on it - declaration is fine and so's
access to fields (i.e. x[0].c = 'a'; would produce the right code), but
members of the anon structs and unions are not inserted into the right
namespace. Tellingly, those older versions will not barf on struct {int
a; struct {int a;};}; - looks like they just have it hacked up somewhere
around the handling of . and -> instead of doing the right thing.
The easiest way to deal with that crap is to turn initialization of
those fields (in the only place where we have such initializer of
iov_iter) into plain assignment.
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sat, 14 Jun 2014 21:51:25 +0000 (14:51 -0700)]
Merge tag 'hsi-for-3.16-fixes1' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-hsi
Pull HSI build fixes from Sebastian Reichel:
- tighten dependency between ssi-protocol and omap-ssi to fix build
failures with randconfig.
- use normal module refcounting in omap driver to fix build with
disabled module support
* tag 'hsi-for-3.16-fixes1' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-hsi:
hsi: omap_ssi_port: use normal module refcounting
HSI: fix omap ssi driver dependency
Linus Torvalds [Sat, 14 Jun 2014 21:46:29 +0000 (14:46 -0700)]
Merge branch 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 vdso fixes from Peter Anvin:
"Fixes for x86/vdso.
One is a simple build fix for bigendian hosts, one is to make "make
vdso_install" work again, and the rest is about working around a bug
in Google's Go language -- two are documentation patches that improves
the sample code that the Go coders took, modified, and broke; the
other two implements a workaround that keeps existing Go binaries from
segfaulting at least"
* 'x86-vdso-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/vdso: Fix vdso_install
x86/vdso: Hack to keep 64-bit Go programs working
x86/vdso: Add PUT_LE to store little-endian values
x86/vdso/doc: Make vDSO examples more portable
x86/vdso/doc: Rename vdso_test.c to vdso_standalone_test_x86.c
x86, vdso: Remove one final use of htole16()
Linus Torvalds [Sat, 14 Jun 2014 21:43:23 +0000 (14:43 -0700)]
Merge tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon updates from Guenter Roeck:
- new driver for Sensirion SHTC1 humidity / temperature sensor
- convert ltc4151 and vexpress drivers to use devm functions
- drop generic chip detection from lm85 driver
- avoid forward declarations in atxp1 driver
- fix sign extensions in ina2xx driver
* tag 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
hwmon: vexpress: Use devm helper for hwmon device registration
hwmon: (atxp1) Avoid forward declaration
hwmon: add support for Sensirion SHTC1 sensor
hwmon: (ltc4151) Convert to devm_hwmon_device_register_with_groups
hwmon: (lm85) Drop generic detection
hwmon: (ina2xx) Cast to s16 on shunt and current regs
Eric Dumazet [Thu, 12 Jun 2014 23:13:06 +0000 (16:13 -0700)]
udp: ipv4: do not waste time in __udp4_lib_mcast_demux_lookup
Its too easy to add thousand of UDP sockets on a particular bucket,
and slow down an innocent multicast receiver.
Early demux is supposed to be an optimization, we should avoid spending
too much time in it.
It is interesting to note __udp4_lib_demux_lookup() only tries to
match first socket in the chain.
10 is the threshold we already have in __udp4_lib_lookup() to switch
to secondary hash.
Fixes: 421b3885bf6d5 ("udp: ipv4: Add udp early demux") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: David Held <drheld@google.com> Cc: Shawn Bohrer <sbohrer@rgmadvisors.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Cong Wang [Thu, 12 Jun 2014 18:53:10 +0000 (11:53 -0700)]
vxlan: use dev->needed_headroom instead of dev->hard_header_len
When we mirror packets from a vxlan tunnel to other device,
the mirror device should see the same packets (that is, without
outer header). Because vxlan tunnel sets dev->hard_header_len,
tcf_mirred() resets mac header back to outer mac, the mirror device
actually sees packets with outer headers
Vxlan tunnel should set dev->needed_headroom instead of
dev->hard_header_len, like what other ip tunnels do. This fixes
the above problem.
Cc: "David S. Miller" <davem@davemloft.net> Cc: stephen hemminger <stephen@networkplumber.org> Cc: Pravin B Shelar <pshelar@nicira.com> Signed-off-by: Cong Wang <cwang@twopensource.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Andy Lutomirski [Thu, 12 Jun 2014 15:28:10 +0000 (08:28 -0700)]
x86/vdso: Fix vdso_install
"make vdso_install" installs unstripped versions of the vdso objects
for the benefit of the debugger. This was broken by checkin:
6f121e548f83 x86, vdso: Reimplement vdso.so preparation in build-time C
The filenames are different now, so update the Makefile to cope.
This still installs the 64-bit vdso as vdso64.so. We believe this
will be okay, as the only known user is a patched gdb which is known
to use build-ids, but if it turns out to be a problem we may have to
add a link.
Dan McLeran [Fri, 6 Jun 2014 14:27:27 +0000 (08:27 -0600)]
NVMe: Fix START_STOP_UNIT Scsi->NVMe translation.
This patch contains several fixes for Scsi START_STOP_UNIT. The previous
code did not account for signed vs. unsigned arithmetic which resulted
in an invalid lowest power state caculation when the device only supports
1 power state.
The code for Power Condition == 2 (Idle) was not following the spec. The
spec calls for setting the device to specific power states, depending
upon Power Condition Modifier, without accounting for the number of
power states supported by the device.
The code for Power Condition == 3 (Standby) was using a hard-coded '0'
which is replaced with the macro POWER_STATE_0.
Signed-off-by: Dan McLeran <daniel.mcleran@intel.com> Reviewed-by: Vishal Verma <vishal.l.verma@linux.intel.com> Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Eric Sandeen [Thu, 12 Jun 2014 05:53:44 +0000 (00:53 -0500)]
btrfs: fix error handling in create_pending_snapshot
fcebe456 cut and pasted some code to a later point
in create_pending_snapshot(), but didn't switch
to the appropriate error handling for this stage
of the function.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Chris Mason <clm@fb.com>
Eric Sandeen [Thu, 12 Jun 2014 05:39:58 +0000 (00:39 -0500)]
btrfs: fix use of uninit "ret" in end_extent_writepage()
If this condition in end_extent_writepage() is false:
if (tree->ops && tree->ops->writepage_end_io_hook)
we will then test an uninitialized "ret" at:
ret = ret < 0 ? ret : -EIO;
The test for ret is for the case where ->writepage_end_io_hook
failed, and we'd choose that ret as the error; but if
there is no ->writepage_end_io_hook, nothing sets ret.
Initializing ret to 0 should be sufficient; if
writepage_end_io_hook wasn't set, (!uptodate) means
non-zero err was passed in, so we choose -EIO in that case.
Signed-of-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Chris Mason <clm@fb.com>
Filipe Manana [Thu, 12 Jun 2014 01:47:37 +0000 (02:47 +0100)]
Btrfs: fix qgroups sanity test crash or hang
Often when running the qgroups sanity test, a crash or a hang happened.
This is because the extent buffer the test uses for the root node doesn't
have an header level explicitly set, making it have a random level value.
This is a problem when it's not zero for the btrfs_search_slot() calls
the test ends up doing, resulting in crashes or hangs such as the following: