- 06 Dec, 2012 37 commits
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Arend van Spriel authored
commit 2b0a53d5 upstream. In regular use block-ack timeouts can happen so it does not make sense to fill the log with these messages. Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com> Reviewed-by: Alwin Beukers <alwin@broadcom.com> Signed-off-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Marek Vasut authored
commit 2843b673 upstream. The USB recovery mode present in i.MX28 ROM emulates USB HID. It needs this quirk to behave properly. Signed-off-by: Marek Vasut <marex@denx.de> Cc: Chen Peter <B29397@freescale.com> Cc: Greg KH <greg@kroah.com> Cc: Jiri Kosina <jkosina@suse.cz> [jkosina@suse.cz: fix alphabetical ordering] Signed-off-by: Jiri Kosina <jkosina@suse.cz> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Andreas Schwab authored
commit 34fa78b5 upstream. The sigaddset/sigdelset/sigismember functions that are implemented with bitfield insn cannot allow the sigset argument to be placed in a data register since the sigset is wider than 32 bits. Remove the "d" constraint from the asm statements. The effect of the bug is that sending RT signals does not work, the signal number is truncated modulo 32. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Mauro Carvalho Chehab authored
commit 25ec43d3 upstream. The previous website doesn't exist anymore. Update it to one site that actually exists. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Takashi Iwai authored
commit b0354385 upstream. Currently i915 driver checks [PCH_]LVDS register bits to decide whether to set up the dual-link or the single-link mode. This relies implicitly on that BIOS initializes the register properly at boot. However, BIOS doesn't initialize it always. When the machine is booted with the closed lid, BIOS skips the LVDS reg initialization. This ends up in blank output on a machine with a dual-link LVDS when you open the lid after the boot. This patch adds a workaround for that problem by checking the initial LVDS register value in VBT. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=37742Tested-By: Paulo Zanoni <paulo.r.zanoni@intel.com> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@gmail.com> Reviewed-by: Adam Jackson <ajax@redhat.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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joshua.a.hay@intel.com authored
commit df376f0d upstream. This patch adds device support for Ethernet Controller X540-AT1. Signed-off-by: Josh Hay <joshua.a.hay@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Emil Tantilov authored
commit 9e791e4a upstream. Support for new 82599 based quad port adapter. Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Dmitry Torokhov authored
commit 1729ad1f upstream. In addition to some laptops needing i8042 reset after resuming from S2R to get their touchpads working there is another class of laptops - ones that need i8042 reset before going to S2R, otherwise they will simply reboot instead of resuming. See https://bugzilla.kernel.org/show_bug.cgi?id=15612 This change forces reset of i8042 before doing S2R. Reported-by: Stefan Koch <stefan_koch@gmx.net> Tested-by: Alexander van Loon <a.vanloon@alexandervanloon.nl> Signed-off-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Yinghai Lu authored
commit a4ac9fea upstream. During debug of one SRIOV enabled hotplug device, we found found that add_size is not passed properly. The device has devices under two level bridges: +-[0000:80]-+-00.0-[81-8f]-- | +-01.0-[90-9f]-- | +-02.0-[a0-af]----00.0-[a1-a3]--+-02.0-[a2]--+-00.0 Oracle Corporation Device | | \-03.0-[a3]--+-00.0 Oracle Corporation Device Which means later the parent bridge will not try to add a big enough range: [ 557.455077] pci 0000:a0:00.0: BAR 14: assigned [mem 0xf9000000-0xf93fffff] [ 557.461974] pci 0000:a0:00.0: BAR 15: assigned [mem 0xf6000000-0xf61fffff pref] [ 557.469340] pci 0000:a1:02.0: BAR 14: assigned [mem 0xf9000000-0xf91fffff] [ 557.476231] pci 0000:a1:02.0: BAR 15: assigned [mem 0xf6000000-0xf60fffff pref] [ 557.483582] pci 0000:a1:03.0: BAR 14: assigned [mem 0xf9200000-0xf93fffff] [ 557.490468] pci 0000:a1:03.0: BAR 15: assigned [mem 0xf6100000-0xf61fffff pref] [ 557.497833] pci 0000:a1:03.0: BAR 14: can't assign mem (size 0x200000) [ 557.504378] pci 0000:a1:03.0: failed to add optional resources res=[mem 0xf9200000-0xf93fffff] [ 557.513026] pci 0000:a1:02.0: BAR 14: can't assign mem (size 0x200000) [ 557.519578] pci 0000:a1:02.0: failed to add optional resources res=[mem 0xf9000000-0xf91fffff] It turns out we did not calculate size1 properly. static resource_size_t calculate_memsize(resource_size_t size, resource_size_t min_size, resource_size_t size1, resource_size_t old_size, resource_size_t align) { if (size < min_size) size = min_size; if (old_size == 1 ) old_size = 0; if (size < old_size) size = old_size; size = ALIGN(size + size1, align); return size; } We should not pass add_size with min_size in calculate_memsize since that will make add_size not contribute final add_size. So just pass add_size with size1 to calculate_memsize(). With this change, we should have chance to remove extra addon in pci_reassign_resource. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jan Safrata authored
commit 0658a336 upstream. The use of kfree(serial) in error cases of usb_serial_probe was invalid - usb_serial structure allocated in create_serial() gets reference of usb_device that needs to be put, so we need to use usb_serial_put() instead of simple kfree(). Signed-off-by: Jan Safrata <jan.nikitenko@gmail.com> Acked-by: Johan Hovold <jhovold@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Tom Herbert authored
[ Upstream commit baefa31d ] In commit c445477d which adds aRFS to the kernel, the CPU selected for RFS is not set correctly when CPU is changing. This is causing OOO packets and probably other issues. Signed-off-by: Tom Herbert <therbert@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Ben Hutchings <bhutchings@solarflare.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jiri Pirko authored
[ Upstream commit a652208e ] Check (ha->addr == dev->dev_addr) is always true because dev_addr_init() sets this. Correct the check to behave properly on addr removal. Signed-off-by: Jiri Pirko <jiri@resnulli.us> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Hannes Frederic Sowa authored
[ Upstream commit d4596bad ] Cc: Stephen Hemminger <shemminger@vyatta.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Xi Wang authored
[ Upstream commit 0c9f79be ] (1<<optname) is undefined behavior in C with a negative optname or optname larger than 31. In those cases the result of the shift is not necessarily zero (e.g., on x86). This patch simplifies the code with a switch statement on optname. It also allows the compiler to generate better code (e.g., using a 64-bit mask). Signed-off-by: Xi Wang <xi.wang@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Ulrich Weber authored
commit 38fe36a2 upstream. ICMP tuples have id in src and type/code in dst. So comparing src.u.all with dst.u.all will always fail here and ip_xfrm_me_harder() is called for every ICMP packet, even if there was no NAT. Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com> [Pablo Neira Ayuso: Backported to.3.0] Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jozsef Kadlecsik authored
commit 4a70bbfa upstream. We spare nothing by not validating the sequence number of dataless ACK packets and enabling it makes harder off-path attacks. See: "Reflection scan: an Off-Path Attack on TCP" by Jan Wrobel, http://arxiv.org/abs/1201.2074Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jozsef Kadlecsik authored
commit 64f509ce upstream. Clients should not send such packets. By accepting them, we open up a hole by wich ephemeral ports can be discovered in an off-path attack. See: "Reflection scan: an Off-Path Attack on TCP" by Jan Wrobel, http://arxiv.org/abs/1201.2074Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Yinghai Lu authored
commit f82f64dd upstream. Commit 844ab6f9 x86, mm: Find_early_table_space based on ranges that are actually being mapped added back some lines back wrongly that has been removed in commit 7b16bbf9 Revert "x86/mm: Fix the size calculation of mapping tables" remove them again. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/CAE9FiQW_vuaYQbmagVnxT2DGsYc=9tNeAbdBq53sYkitPOwxSQ@mail.gmail.comAcked-by: Jacob Shin <jacob.shin@amd.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jacob Shin authored
commit 844ab6f9 upstream. Current logic finds enough space for direct mapping page tables from 0 to end. Instead, we only need to find enough space to cover mr[0].start to mr[nr_range].end -- the range that is actually being mapped by init_memory_mapping() This is needed after 1bbbbe77, to address the panic reported here: https://lkml.org/lkml/2012/10/20/160 https://lkml.org/lkml/2012/10/21/157Signed-off-by: Jacob Shin <jacob.shin@amd.com> Link: http://lkml.kernel.org/r/20121024195311.GB11779@jshin-ToonieTested-by: Tom Rini <trini@ti.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> [bwh: Backported to 3.2: - Adjust context - The log message format is a bit different] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jacob Shin authored
commit 1bbbbe77 upstream. On systems with very large memory (1 TB in our case), BIOS may report a reserved region or a hole in the E820 map, even above the 4 GB range. Exclude these from the direct mapping. [ hpa: this should be done not just for > 4 GB but for everything above the legacy region (1 MB), at the very least. That, however, turns out to require significant restructuring. That work is well underway, but is not suitable for rc/stable. ] Signed-off-by: Jacob Shin <jacob.shin@amd.com> Link: http://lkml.kernel.org/r/1319145326-13902-1-git-send-email-jacob.shin@amd.comSigned-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Hugh Dickins authored
commit 0f3c42f5 upstream. Under a particular load on one machine, I have hit shmem_evict_inode()'s BUG_ON(inode->i_blocks), enough times to narrow it down to a particular race between swapout and eviction. It comes from the "if (freed > 0)" asymmetry in shmem_recalc_inode(), and the lack of coherent locking between mapping's nrpages and shmem's swapped count. There's a window in shmem_writepage(), between lowering nrpages in shmem_delete_from_page_cache() and then raising swapped count, when the freed count appears to be +1 when it should be 0, and then the asymmetry stops it from being corrected with -1 before hitting the BUG. One answer is coherent locking: using tree_lock throughout, without info->lock; reasonable, but the raw_spin_lock in percpu_counter_add() on used_blocks makes that messier than expected. Another answer may be a further effort to eliminate the weird shmem_recalc_inode() altogether, but previous attempts at that failed. So far undecided, but for now change the BUG_ON to WARN_ON: in usual circumstances it remains a useful consistency check. Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Michal Hocko authored
commit 9a5a8f19 upstream. oom_badness() takes a totalpages argument which says how many pages are available and it uses it as a base for the score calculation. The value is calculated by mem_cgroup_get_limit which considers both limit and total_swap_pages (resp. memsw portion of it). This is usually correct but since fe35004f ("mm: avoid swapping out with swappiness==0") we do not swap when swappiness is 0 which means that we cannot really use up all the totalpages pages. This in turn confuses oom score calculation if the memcg limit is much smaller than the available swap because the used memory (capped by the limit) is negligible comparing to totalpages so the resulting score is too small if adj!=0 (typically task with CAP_SYS_ADMIN or non zero oom_score_adj). A wrong process might be selected as result. The problem can be worked around by checking mem_cgroup_swappiness==0 and not considering swap at all in such a case. Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Zhao Yakui authored
commit ac207ed2 upstream. The TTM page can be allocated from high memory. In such case it is wrong to use the page_address(page) as the virtual address for the high memory page. bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=50241Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com> Signed-off-by: Dave Airlie <airlied@redhat.com> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Alex Deucher authored
commit b9196395 upstream. Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=50431Reported-by: David Binderman <dcb314@hotmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Reviewed-by: Michel Dänzer <michel.daenzer@amd.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Dan Williams authored
commit c0bc3098 upstream. Signed-off-by: Dan Williams <dcbw@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Dan Williams authored
commit fcb21645 upstream. The Dell 5800 appears to be a simple rebrand of the Novatel E362. Signed-off-by: Dan Williams <dcbw@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Heiko Carstens authored
commit d55c4c61 upstream. When walking page tables we need to make sure that everything is within bounds of the ASCE limit of the task's address space. Otherwise we might calculate e.g. a pud pointer which is not within a pud and dereference it. So check against TASK_SIZE (which is the ASCE limit) before walking page tables. Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jani Nikula authored
commit d0ddfbd3 upstream. Any failures in intel_sdvo_init() after the intel_sdvo_setup_output() call left behind ghost connectors, attached (with a dangling pointer) to the sdvo that has been cleaned up and freed. Properly destroy any connectors attached to the encoder. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=46381 CC: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Tested-by: bjo@nord-west.org [danvet: added a comment to explain why we need to clean up connectors even when sdvo_output_setup fails.] Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Johannes Berg authored
commit 43c771a1 upstream. When in world roaming mode, allow 40 MHz to be used on channels 12 and 13 so that an AP that is, e.g., using HT40+ on channel 9 (in the UK) can be used. Reported-by: Eddie Chapman <eddie@ehuk.net> Tested-by: Eddie Chapman <eddie@ehuk.net> Acked-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Martin Schwidefsky authored
commit fa968ee2 upstream. If user space is running in primary mode it can switch to secondary or access register mode, this is used e.g. in the clock_gettime code of the vdso. If a signal is delivered to the user space process while it has been running in access register mode the signal handler is executed in access register mode as well which will result in a crash most of the time. Set the address space control bits in the PSW to the default for the execution of the signal handler and make sure that the previous address space control is restored on signal return. Take care that user space can not switch to the kernel address space by modifying the registers in the signal frame. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [bwh: Backported to 3.2: - Adjust filename - The RI bit is not included in PSW_MASK_USER] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Misael Lopez Cruz authored
commit 445632ad upstream. DAPM shutdown incorrectly uses "list" field of codec struct while iterating over probed components (codec_dev_list). "list" field refers to codecs registered in the system, "card_list" field is used for probed components. Signed-off-by: Misael Lopez Cruz <misael.lopez@ti.com> Signed-off-by: Liam Girdwood <lrg@ti.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Tejun Heo authored
commit 201e72ac upstream. dev_cgroup->exceptions is protected with devcgroup_mutex for writes and RCU for reads; however, RCU usage isn't correct. * dev_exception_clean() doesn't use RCU variant of list_del() and kfree(). The function can race with may_access() and may_access() may end up dereferencing already freed memory. Use list_del_rcu() and kfree_rcu() instead. * may_access() may be called only with RCU read locked but doesn't use RCU safe traversal over ->exceptions. Use list_for_each_entry_rcu(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com> Cc: Aristeu Rozanski <aris@redhat.com> Cc: Li Zefan <lizefan@huawei.com> [bwh: Backported to 3.2: - Adjust context - Exception list is called whitelist] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Eric Millbrandt authored
commit 55c6f4cb upstream. When MCLK is supplied externally and BCLK and LRC are configured as outputs (codec is master), the PLL values are only calculated correctly on the first transmission. On subsequent transmissions, at differenct sample rates, the wrong PLL values are used. Test for f_opclk instead of f_pllout to determine if the PLL values are needed. Signed-off-by: Eric Millbrandt <emillbrandt@dekaresearch.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Arik Nemtsov authored
commit 987c285c upstream. These are accessed without a lock when ending STA PSM. If the sta_cleanup timer accesses these lists at the same time, we might crash. This may fix some mysterious crashes we had during ieee80211_sta_ps_deliver_wakeup. Signed-off-by: Arik Nemtsov <arik@wizery.com> Signed-off-by: Ido Yariv <ido@wizery.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Thomas Gleixner authored
commit 59fa6245 upstream. Siddhesh analyzed a failure in the take over of pi futexes in case the owner died and provided a workaround. See: http://sourceware.org/bugzilla/show_bug.cgi?id=14076 The detailed problem analysis shows: Futex F is initialized with PTHREAD_PRIO_INHERIT and PTHREAD_MUTEX_ROBUST_NP attributes. T1 lock_futex_pi(F); T2 lock_futex_pi(F); --> T2 blocks on the futex and creates pi_state which is associated to T1. T1 exits --> exit_robust_list() runs --> Futex F userspace value TID field is set to 0 and FUTEX_OWNER_DIED bit is set. T3 lock_futex_pi(F); --> Succeeds due to the check for F's userspace TID field == 0 --> Claims ownership of the futex and sets its own TID into the userspace TID field of futex F --> returns to user space T1 --> exit_pi_state_list() --> Transfers pi_state to waiter T2 and wakes T2 via rt_mutex_unlock(&pi_state->mutex) T2 --> acquires pi_state->mutex and gains real ownership of the pi_state --> Claims ownership of the futex and sets its own TID into the userspace TID field of futex F --> returns to user space T3 --> observes inconsistent state This problem is independent of UP/SMP, preemptible/non preemptible kernels, or process shared vs. private. The only difference is that certain configurations are more likely to expose it. So as Siddhesh correctly analyzed the following check in futex_lock_pi_atomic() is the culprit: if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) { We check the userspace value for a TID value of 0 and take over the futex unconditionally if that's true. AFAICT this check is there as it is correct for a different corner case of futexes: the WAITERS bit became stale. Now the proposed change - if (unlikely(ownerdied || !(curval & FUTEX_TID_MASK))) { + if (unlikely(ownerdied || + !(curval & (FUTEX_TID_MASK | FUTEX_WAITERS)))) { solves the problem, but it's not obvious why and it wreckages the "stale WAITERS bit" case. What happens is, that due to the WAITERS bit being set (T2 is blocked on that futex) it enforces T3 to go through lookup_pi_state(), which in the above case returns an existing pi_state and therefor forces T3 to legitimately fight with T2 over the ownership of the pi_state (via pi_state->mutex). Probelm solved! Though that does not work for the "WAITERS bit is stale" problem because if lookup_pi_state() does not find existing pi_state it returns -ERSCH (due to TID == 0) which causes futex_lock_pi() to return -ESRCH to user space because the OWNER_DIED bit is not set. Now there is a different solution to that problem. Do not look at the user space value at all and enforce a lookup of possibly available pi_state. If pi_state can be found, then the new incoming locker T3 blocks on that pi_state and legitimately races with T2 to acquire the rt_mutex and the pi_state and therefor the proper ownership of the user space futex. lookup_pi_state() has the correct order of checks. It first tries to find a pi_state associated with the user space futex and only if that fails it checks for futex TID value = 0. If no pi_state is available nothing can create new state at that point because this happens with the hash bucket lock held. So the above scenario changes to: T1 lock_futex_pi(F); T2 lock_futex_pi(F); --> T2 blocks on the futex and creates pi_state which is associated to T1. T1 exits --> exit_robust_list() runs --> Futex F userspace value TID field is set to 0 and FUTEX_OWNER_DIED bit is set. T3 lock_futex_pi(F); --> Finds pi_state and blocks on pi_state->rt_mutex T1 --> exit_pi_state_list() --> Transfers pi_state to waiter T2 and wakes it via rt_mutex_unlock(&pi_state->mutex) T2 --> acquires pi_state->mutex and gains ownership of the pi_state --> Claims ownership of the futex and sets its own TID into the userspace TID field of futex F --> returns to user space This covers all gazillion points on which T3 might come in between T1's exit_robust_list() clearing the TID field and T2 fixing it up. It also solves the "WAITERS bit stale" problem by forcing the take over. Another benefit of changing the code this way is that it makes it less dependent on untrusted user space values and therefor minimizes the possible wreckage which might be inflicted. As usual after staring for too long at the futex code my brain hurts so much that I really want to ditch that whole optimization of avoiding the syscall for the non contended case for PI futexes and rip out the maze of corner case handling code. Unfortunately we can't as user space relies on that existing behaviour, but at least thinking about it helps me to preserve my mental sanity. Maybe we should nevertheless :) Reported-and-tested-by: Siddhesh Poyarekar <siddhesh.poyarekar@gmail.com> Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1210232138540.2756@ionosAcked-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Artem Bityutskiy authored
commit a28ad42a upstream. This is a bugfix for a problem with the following symptoms: 1. A power cut happens 2. After reboot, we try to mount UBIFS 3. Mount fails with "No space left on device" error message UBIFS complains like this: UBIFS error (pid 28225): grab_empty_leb: could not find an empty LEB The root cause of this problem is that when we mount, not all LEBs are categorized. Only those which were read are. However, the 'ubifs_find_free_leb_for_idx()' function assumes that all LEBs were categorized and 'c->freeable_cnt' is valid, which is a false assumption. This patch fixes the problem by teaching 'ubifs_find_free_leb_for_idx()' to always fall back to LPT scanning if no freeable LEBs were found. This problem was reported by few people in the past, but Brent Taylor was able to reproduce it and send me a flash image which cannot be mounted, which made it easy to hunt the bug. Kudos to Brent. Reported-by: Brent Taylor <motobud@gmail.com> Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Artem Bityutskiy authored
commit 98a1eebd upstream. This commit is a preparation for a subsequent bugfix. We introduce a counter for categorized lprops. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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- 16 Nov, 2012 3 commits
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Ben Hutchings authored
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Takashi Iwai authored
commit 10e44239 upstream. The recent change for USB-audio disconnection race fixes introduced a mutex deadlock again. There is a circular dependency between chip->shutdown_rwsem and pcm->open_mutex, depicted like below, when a device is opened during the disconnection operation: A. snd_usb_audio_disconnect() -> card.c::register_mutex -> chip->shutdown_rwsem (write) -> snd_card_disconnect() -> pcm.c::register_mutex -> pcm->open_mutex B. snd_pcm_open() -> pcm->open_mutex -> snd_usb_pcm_open() -> chip->shutdown_rwsem (read) Since the chip->shutdown_rwsem protection in the case A is required only for turning on the chip->shutdown flag and it doesn't have to be taken for the whole operation, we can reduce its window in snd_usb_audio_disconnect(). Reported-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Mirko Lindner authored
commit d663d181 upstream. Re-enable interrupts if it is not our interrupt Signed-off-by: Mirko Lindner <mlindner@marvell.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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