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  1. 10 Aug, 2016 9 commits
    • David Rientjes's avatar
      mm, compaction: abort free scanner if split fails · 21e9f897
      David Rientjes authored 
      commit a4f04f2c upstream.

If the memory compaction free scanner cannot successfully split a free
page (only possible due to per-zone low watermark), terminate the free
scanner rather than continuing to scan memory needlessly.  If the
watermark is insufficient for a free page of order <= cc->order, then
terminate the scanner since all future splits will also likely fail.

This prevents the compaction freeing scanner from scanning all memory on
very large zones (very noticeable for zones > 128GB, for instance) when
all splits will likely fail while holding zone->lock.

compaction_alloc() iterating a 128GB zone has been benchmarked to take
over 400ms on some systems whereas any free page isolated and ready to
be split ends up failing in split_free_page() because of the low
watermark check and thus the iteration continues.

The next time compaction occurs, the freeing scanner will likely start
at the end of the zone again since no success was made previously and we
get the same lengthy iteration until the zone is brought above the low
watermark.  All thp page faults can take >400ms in such a state without
this fix.

Link: http://lkml.kernel.org/r/alpine.DEB.2.10.1606211820350.97086@chino.kir.corp.google.comSigned-off-by: default avatarDavid Rientjes <rientjes@google.com>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      21e9f897
    • Mel Gorman's avatar
      mm, sl[au]b: add __GFP_ATOMIC to the GFP reclaim mask · 5b3114b2
      Mel Gorman authored 
      commit e838a45f upstream.

Commit d0164adc ("mm, page_alloc: distinguish between being unable
to sleep, unwilling to sleep and avoiding waking kswapd") modified
__GFP_WAIT to explicitly identify the difference between atomic callers
and those that were unwilling to sleep.  Later the definition was
removed entirely.

The GFP_RECLAIM_MASK is the set of flags that affect watermark checking
and reclaim behaviour but __GFP_ATOMIC was never added.  Without it,
atomic users of the slab allocator strip the __GFP_ATOMIC flag and
cannot access the page allocator atomic reserves.  This patch addresses
the problem.

The user-visible impact depends on the workload but potentially atomic
allocations unnecessarily fail without this path.

Link: http://lkml.kernel.org/r/20160610093832.GK2527@techsingularity.netSigned-off-by: default avatarMel Gorman <mgorman@techsingularity.net>
Reported-by: default avatarMarcin Wojtas <mw@semihalf.com>
Acked-by: default avatarVlastimil Babka <vbabka@suse.cz>
Acked-by: default avatarMichal Hocko <mhocko@suse.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5b3114b2
    • Ludovic Desroches's avatar
      dmaengine: at_xdmac: double FIFO flush needed to compute residue · 6b373d53
      Ludovic Desroches authored 
      commit 9295c41d upstream.

Due to the way CUBC register is updated, a double flush is needed to
compute an accurate residue. First flush aim is to get data from the DMA
FIFO and second one ensures that we won't report data which are not in
memory.
Signed-off-by: default avatarLudovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9ee ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Reviewed-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      6b373d53
    • Ludovic Desroches's avatar
      dmaengine: at_xdmac: fix residue corruption · 5ce7333f
      Ludovic Desroches authored 
      commit 53398f48 upstream.

An unexpected value of CUBC can lead to a corrupted residue. A more
complex sequence is needed to detect an inaccurate value for NCA or CUBC.
Signed-off-by: default avatarLudovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9ee ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Reviewed-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      5ce7333f
    • Ludovic Desroches's avatar
      dmaengine: at_xdmac: align descriptors on 64 bits · 1b60fcdc
      Ludovic Desroches authored 
      commit 4a9723e8 upstream.

Having descriptors aligned on 64 bits allows update CNDA and CUBC in an
atomic way.
Signed-off-by: default avatarLudovic Desroches <ludovic.desroches@atmel.com>
Fixes: e1f7c9ee ("dmaengine: at_xdmac: creation of the atmel
eXtended DMA Controller driver")
Reviewed-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: default avatarVinod Koul <vinod.koul@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      1b60fcdc
    • Lukas Wunner's avatar
      x86/quirks: Add early quirk to reset Apple AirPort card · ba1eebc7
      Lukas Wunner authored 
      commit abb2bafd upstream.

The EFI firmware on Macs contains a full-fledged network stack for
downloading OS X images from osrecovery.apple.com. Unfortunately
on Macs introduced 2011 and 2012, EFI brings up the Broadcom 4331
wireless card on every boot and leaves it enabled even after
ExitBootServices has been called. The card continues to assert its IRQ
line, causing spurious interrupts if the IRQ is shared. It also corrupts
memory by DMAing received packets, allowing for remote code execution
over the air. This only stops when a driver is loaded for the wireless
card, which may be never if the driver is not installed or blacklisted.

The issue seems to be constrained to the Broadcom 4331. Chris Milsted
has verified that the newer Broadcom 4360 built into the MacBookPro11,3
(2013/2014) does not exhibit this behaviour. The chances that Apple will
ever supply a firmware fix for the older machines appear to be zero.

The solution is to reset the card on boot by writing to a reset bit in
its mmio space. This must be done as an early quirk and not as a plain
vanilla PCI quirk to successfully combat memory corruption by DMAed
packets: Matthew Garrett found out in 2012 that the packets are written
to EfiBootServicesData memory (http://mjg59.dreamwidth.org/11235.html).
This type of memory is made available to the page allocator by
efi_free_boot_services(). Plain vanilla PCI quirks run much later, in
subsys initcall level. In-between a time window would be open for memory
corruption. Random crashes occurring in this time window and attributed
to DMAed packets have indeed been observed in the wild by Chris
Bainbridge.

When Matthew Garrett analyzed the memory corruption issue in 2012, he
sought to fix it with a grub quirk which transitions the card to D3hot:
http://git.savannah.gnu.org/cgit/grub.git/commit/?id=9d34bb85da56

This approach does not help users with other bootloaders and while it
may prevent DMAed packets, it does not cure the spurious interrupts
emanating from the card. Unfortunately the card's mmio space is
inaccessible in D3hot, so to reset it, we have to undo the effect of
Matthew's grub patch and transition the card back to D0.

Note that the quirk takes a few shortcuts to reduce the amount of code:
The size of BAR 0 and the location of the PM capability is identical
on all affected machines and therefore hardcoded. Only the address of
BAR 0 differs between models. Also, it is assumed that the BCMA core
currently mapped is the 802.11 core. The EFI driver seems to always take
care of this.

Michael Büsch, Bjorn Helgaas and Matt Fleming contributed feedback
towards finding the best solution to this problem.

The following should be a comprehensive list of affected models:
    iMac13,1        2012  21.5"       [Root Port 00:1c.3 = 8086:1e16]
    iMac13,2        2012  27"         [Root Port 00:1c.3 = 8086:1e16]
    Macmini5,1      2011  i5 2.3 GHz  [Root Port 00:1c.1 = 8086:1c12]
    Macmini5,2      2011  i5 2.5 GHz  [Root Port 00:1c.1 = 8086:1c12]
    Macmini5,3      2011  i7 2.0 GHz  [Root Port 00:1c.1 = 8086:1c12]
    Macmini6,1      2012  i5 2.5 GHz  [Root Port 00:1c.1 = 8086:1e12]
    Macmini6,2      2012  i7 2.3 GHz  [Root Port 00:1c.1 = 8086:1e12]
    MacBookPro8,1   2011  13"         [Root Port 00:1c.1 = 8086:1c12]
    MacBookPro8,2   2011  15"         [Root Port 00:1c.1 = 8086:1c12]
    MacBookPro8,3   2011  17"         [Root Port 00:1c.1 = 8086:1c12]
    MacBookPro9,1   2012  15"         [Root Port 00:1c.1 = 8086:1e12]
    MacBookPro9,2   2012  13"         [Root Port 00:1c.1 = 8086:1e12]
    MacBookPro10,1  2012  15"         [Root Port 00:1c.1 = 8086:1e12]
    MacBookPro10,2  2012  13"         [Root Port 00:1c.1 = 8086:1e12]

For posterity, spurious interrupts caused by the Broadcom 4331 wireless
card resulted in splats like this (stacktrace omitted):

    irq 17: nobody cared (try booting with the "irqpoll" option)
    handlers:
    [<ffffffff81374370>] pcie_isr
    [<ffffffffc0704550>] sdhci_irq [sdhci] threaded [<ffffffffc07013c0>] sdhci_thread_irq [sdhci]
    [<ffffffffc0a0b960>] azx_interrupt [snd_hda_codec]
    Disabling IRQ #17

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=79301
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=111781
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=728916
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=895951#c16
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1009819
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1098621
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1149632#c5
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1279130
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1332732
Tested-by: Konstantin Simanov <k.simanov@stlk.ru>        # [MacBookPro8,1]
Tested-by: Lukas Wunner <lukas@wunner.de>                # [MacBookPro9,1]
Tested-by: Bryan Paradis <bryan.paradis@gmail.com>       # [MacBookPro9,2]
Tested-by: Andrew Worsley <amworsley@gmail.com>          # [MacBookPro10,1]
Tested-by: Chris Bainbridge <chris.bainbridge@gmail.com> # [MacBookPro10,2]
Signed-off-by: default avatarLukas Wunner <lukas@wunner.de>
Acked-by: default avatarRafał Miłecki <zajec5@gmail.com>
Acked-by: default avatarMatt Fleming <matt@codeblueprint.co.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Chris Milsted <cmilsted@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Michael Buesch <m@bues.ch>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: b43-dev@lists.infradead.org
Cc: linux-pci@vger.kernel.org
Cc: linux-wireless@vger.kernel.org
Link: http://lkml.kernel.org/r/48d0972ac82a53d460e5fce77a07b2560db95203.1465690253.git.lukas@wunner.de
[ Did minor readability edits. ]
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      ba1eebc7
    • Lukas Wunner's avatar
      x86/quirks: Reintroduce scanning of secondary buses · dd4eb74e
      Lukas Wunner authored 
      commit 850c3210 upstream.

We used to scan secondary buses until the following commit that
was applied in 2009:

  8659c406 ("x86: only scan the root bus in early PCI quirks")

which commit constrained early quirks to the root bus only. Its
motivation was to prevent application of the nvidia_bugs quirk
on secondary buses.

We're about to add a quirk to reset the Broadcom 4331 wireless card on
2011/2012 Macs, which is located on a secondary bus behind a PCIe root
port. To facilitate that, reintroduce scanning of secondary buses.

The commit message of 8659c406 notes that scanning only the root bus
"saves quite some unnecessary scanning work". The algorithm used prior
to 8659c406 was particularly time consuming because it scanned
buses 0 to 31 brute force. To avoid lengthening boot time, employ a
recursive strategy which only scans buses that are actually reachable
from the root bus.

Yinghai Lu pointed out that the secondary bus number read from a
bridge's config space may be invalid, in particular a value of 0 would
cause an infinite loop. The PCI core goes beyond that and recurses to a
child bus only if its bus number is greater than the parent bus number
(see pci_scan_bridge()). Since the root bus is numbered 0, this implies
that secondary buses may not be 0. Do the same on early scanning.

If this algorithm is found to significantly impact boot time or cause
infinite loops on broken hardware, it would be possible to limit its
recursion depth: The Broadcom 4331 quirk applies at depth 1, all others
at depth 0, so the bus need not be scanned deeper than that for now. An
alternative approach would be to revert to scanning only the root bus,
and apply the Broadcom 4331 quirk to the root ports 8086:1c12, 8086:1e12
and 8086:1e16. Apple always positioned the card behind either of these
three ports. The quirk would then check presence of the card in slot 0
below the root port and do its deed.
Signed-off-by: default avatarLukas Wunner <lukas@wunner.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: linux-pci@vger.kernel.org
Link: http://lkml.kernel.org/r/f0daa70dac1a9b2483abdb31887173eb6ab77bdf.1465690253.git.lukas@wunner.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      dd4eb74e
    • Lukas Wunner's avatar
      x86/quirks: Apply nvidia_bugs quirk only on root bus · bab5a36c
      Lukas Wunner authored 
      commit 447d29d1 upstream.

Since the following commit:

  8659c406 ("x86: only scan the root bus in early PCI quirks")

... early quirks are only applied to devices on the root bus.

The motivation was to prevent application of the nvidia_bugs quirk on
secondary buses.

We're about to reintroduce scanning of secondary buses for a quirk to
reset the Broadcom 4331 wireless card on 2011/2012 Macs. To prevent
regressions, open code the requirement to apply nvidia_bugs only on the
root bus.
Signed-off-by: default avatarLukas Wunner <lukas@wunner.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/4d5477c1d76b2f0387a780f2142bbcdd9fee869b.1465690253.git.lukas@wunner.deSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      bab5a36c
    • Michał Pecio's avatar
      USB: OHCI: Don't mark EDs as ED_OPER if scheduling fails · 2053f7db
      Michał Pecio authored 
      commit c66f59ee upstream.

Since ed_schedule begins with marking the ED as "operational",
the ED may be left in such state even if scheduling actually
fails.

This allows future submission attempts to smuggle this ED to the
hardware behind the scheduler's back and without linking it to
the ohci->eds_in_use list.

The former causes bandwidth saturation and data loss on isoc
endpoints, the latter crashes the kernel when attempt is made
to unlink such ED from this list.

Fix ed_schedule to update ED state only on successful return.
Signed-off-by: default avatarMichal Pecio <michal.pecio@gmail.com>
Acked-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
      2053f7db
  3. 27 Jul, 2016 31 commits
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