linux-stable.git/arch, branch v4.4.8

Revert "PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()"

2016-04-20T06:42:16+00:00

commit 6c777e8799a93e3bdb67bec622429e1b48dc90fb upstream.

991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and
pcibios_free_irq()") appeared in v4.3 and helps support IOAPIC hotplug.

Олег reported that the Elcus-1553 TA1-PCI driver worked in v4.2 but not
v4.3 and bisected it to 991de2e59090.  Sunjin reported that the RocketRAID
272x driver worked in v4.2 but not v4.3.  In both cases booting with
"pci=routirq" is a workaround.

I think the problem is that after 991de2e59090, we no longer call
pcibios_enable_irq() for upstream bridges.  Prior to 991de2e59090, when a
driver called pci_enable_device(), we recursively called
pcibios_enable_irq() for upstream bridges via pci_enable_bridge().

After 991de2e59090, we call pcibios_enable_irq() from pci_device_probe()
instead of the pci_enable_device() path, which does *not* call
pcibios_enable_irq() for upstream bridges.

Revert 991de2e59090 to fix these driver regressions.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211
Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()")
Reported-and-tested-by: Олег Мороз 
Reported-by: Sunjin Yang 
Signed-off-by: Bjorn Helgaas 
Acked-by: Rafael J. Wysocki 
CC: Jiang Liu 
Signed-off-by: Greg Kroah-Hartman

Revert "PCI: Add helpers to manage pci_dev->irq and pci_dev->irq_managed"

2016-04-20T06:42:16+00:00

commit 67b4eab91caf2ad574cab1b17ae09180ea2e116e upstream.

Revert 811a4e6fce09 ("PCI: Add helpers to manage pci_dev->irq and
pci_dev->irq_managed").

This is part of reverting 991de2e59090 ("PCI, x86: Implement
pcibios_alloc_irq() and pcibios_free_irq()") to fix regressions it
introduced.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211
Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()")
Signed-off-by: Bjorn Helgaas 
Acked-by: Rafael J. Wysocki 
CC: Jiang Liu 
Signed-off-by: Greg Kroah-Hartman

Revert "x86/PCI: Don't alloc pcibios-irq when MSI is enabled"

2016-04-20T06:42:16+00:00

commit fe25d078874f2c29c38f4160467d74f5756537c9 upstream.

Revert 8affb487d4a4 ("x86/PCI: Don't alloc pcibios-irq when MSI is
enabled").

This is part of reverting 991de2e59090 ("PCI, x86: Implement
pcibios_alloc_irq() and pcibios_free_irq()") to fix regressions it
introduced.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=111211
Fixes: 991de2e59090 ("PCI, x86: Implement pcibios_alloc_irq() and pcibios_free_irq()")
Signed-off-by: Bjorn Helgaas 
Acked-by: Rafael J. Wysocki 
CC: Jiang Liu 
CC: Joerg Roedel 
Signed-off-by: Greg Kroah-Hartman

arm64: replace read_lock to rcu lock in call_step_hook

2016-04-20T06:42:14+00:00

commit cf0a25436f05753aca5151891aea4fd130556e2a upstream.

BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917
in_atomic(): 1, irqs_disabled(): 128, pid: 383, name: sh
Preemption disabled at:[] kgdb_cpu_enter+0x158/0x6b8

CPU: 3 PID: 383 Comm: sh Tainted: G        W       4.1.13-rt13 #2
Hardware name: Freescale Layerscape 2085a RDB Board (DT)
Call trace:
[] dump_backtrace+0x0/0x128
[] show_stack+0x24/0x30
[] dump_stack+0x80/0xa0
[] ___might_sleep+0x18c/0x1a0
[] __rt_spin_lock+0x2c/0x40
[] rt_read_lock+0x40/0x58
[] single_step_handler+0x38/0xd8
[] do_debug_exception+0x58/0xb8
Exception stack(0xffff80834a1e7c80 to 0xffff80834a1e7da0)
7c80: ffffff9c ffffffff 92c23ba0 0000ffff 4a1e7e40 ffff8083 001bfcc4 ffff8000
7ca0: f2000400 00000000 00000000 00000000 4a1e7d80 ffff8083 0049501c ffff8000
7cc0: 00005402 00000000 00aaa210 ffff8000 4a1e7ea0 ffff8083 000833f4 ffff8000
7ce0: ffffff9c ffffffff 92c23ba0 0000ffff 4a1e7ea0 ffff8083 001bfcc0 ffff8000
7d00: 4a0fc400 ffff8083 00005402 00000000 4a1e7d40 ffff8083 00490324 ffff8000
7d20: ffffff9c 00000000 92c23ba0 0000ffff 000a0000 00000000 00000000 00000000
7d40: 00000008 00000000 00080000 00000000 92c23b8b 0000ffff 92c23b8e 0000ffff
7d60: 00000038 00000000 00001cb2 00000000 00000005 00000000 92d7b498 0000ffff
7d80: 01010101 01010101 92be9000 0000ffff 00000000 00000000 00000030 00000000
[] el1_dbg+0x18/0x6c

This issue is similar with 62c6c61("arm64: replace read_lock to rcu lock in
call_break_hook"), but comes to single_step_handler.

This also solves kgdbts boot test silent hang issue on 4.4 -rt kernel.

Signed-off-by: Yang Shi 
Acked-by: Will Deacon 
Signed-off-by: Catalin Marinas 
Signed-off-by: Greg Kroah-Hartman

pcmcia: db1xxx_ss: fix last irq_to_gpio user

2016-04-20T06:42:09+00:00

commit e34b6fcf9b09ec9d93503edd5f81489791ffd602 upstream.

remove the usage of removed irq_to_gpio() function.  On pre-DB1200
boards, pass the actual carddetect GPIO number instead of the IRQ,
because we need the gpio to actually test card status (inserted or
not) and can get the irq number with gpio_to_irq() instead.

Tested on DB1300 and DB1500, this patch fixes PCMCIA on the DB1500,
which used irq_to_gpio().

Fixes: 832f5dacfa0b ("MIPS: Remove all the uses of custom gpio.h")
Signed-off-by: Manuel Lauss 
Acked-by: Arnd Bergmann 
Reviewed-by: Linus Walleij 
Cc: linux-pcmcia@lists.infradead.org
Cc: Linux-MIPS 
Patchwork: https://patchwork.linux-mips.org/patch/12747/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix MSA ld unaligned failure cases

2016-04-20T06:42:08+00:00

commit fa8ff601d72bad3078ddf5ef17a5547700d06908 upstream.

Copying the content of an MSA vector from user memory may involve TLB
faults & mapping in pages. This will fail when preemption is disabled
due to an inability to acquire mmap_sem from do_page_fault, which meant
such vector loads to unmapped pages would always fail to be emulated.
Fix this by disabling preemption later only around the updating of
vector register state.

This change does however introduce a race between performing the load
into thread context & the thread being preempted, saving its current
live context & clobbering the loaded value. This should be a rare
occureence, so optimise for the fast path by simply repeating the load if
we are preempted.

Additionally if the copy failed then the failure path was taken with
preemption left disabled, leading to the kernel typically encountering
further issues around sleeping whilst atomic. The change to where
preemption is disabled avoids this issue.

Fixes: e4aa1f153add "MIPS: MSA unaligned memory access support"
Reported-by: James Hogan 
Signed-off-by: Paul Burton 
Reviewed-by: James Hogan 
Cc: Leonid Yegoshin 
Cc: Maciej W. Rozycki 
Cc: James Cowgill 
Cc: Markos Chandras 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/12345/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: reduce default value of halt_poll_ns parameter

2016-04-20T06:42:07+00:00

commit 14ebda3394fd3e5388747e742e510b0802a65d24 upstream.

Windows lets applications choose the frequency of the timer tick,
and in Windows 10 the maximum rate was changed from 1024 Hz to
2048 Hz.  Unfortunately, because of the way the Windows API
works, most applications who need a higher rate than the default
64 Hz will just do

   timeGetDevCaps(&tc, sizeof(tc));
   timeBeginPeriod(tc.wPeriodMin);

and pick the maximum rate.  This causes very high CPU usage when
playing media or games on Windows 10, even if the guest does not
actually use the CPU very much, because the frequent timer tick
causes halt_poll_ns to kick in.

There is no really good solution, especially because Microsoft
could sooner or later bump the limit to 4096 Hz, but for now
the best we can do is lower a bit the upper limit for
halt_poll_ns. :-(

Reported-by: Jon Panozzo 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: Inject pending interrupt even if pending nmi exist

2016-04-20T06:42:07+00:00

commit 321c5658c5e9192dea0d58ab67cf1791e45b2b26 upstream.

Non maskable interrupts (NMI) are preferred to interrupts in current
implementation. If a NMI is pending and NMI is blocked by the result
of nmi_allowed(), pending interrupt is not injected and
enable_irq_window() is not executed, even if interrupts injection is
allowed.

In old kernel (e.g. 2.6.32), schedule() is often called in NMI context.
In this case, interrupts are needed to execute iret that intends end
of NMI. The flag of blocking new NMI is not cleared until the guest
execute the iret, and interrupts are blocked by pending NMI. Due to
this, iret can't be invoked in the guest, and the guest is starved
until block is cleared by some events (e.g. canceling injection).

This patch injects pending interrupts, when it's allowed, even if NMI
is blocked. And, If an interrupts is pending after executing
inject_pending_event(), enable_irq_window() is executed regardless of
NMI pending counter.

Signed-off-by: Yuki Shibuya 
Suggested-by: Paolo Bonzini 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

arm64: opcodes.h: Add arm big-endian config options before including arm header

2016-04-20T06:41:55+00:00

commit a6002ec5a8c68e69706b2efd6db6d682d0ab672c upstream.

arm and arm64 use different config options to specify big endian. This
needs taking into account when including code/headers between the two
architectures.

A case in point is PAN, which uses the __instr_arm() macro to output
instructions. The macro comes from opcodes.h, which lives under arch/arm.
On a big-endian build the mismatched config options mean the instruction
isn't byte swapped correctly, resulting in undefined instruction exceptions
during boot:

| alternatives: patching kernel code
| kdevtmpfs[87]: undefined instruction: pc=ffffffc0004505b4
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| Internal error: Oops - undefined instruction: 0 [#1] SMP
| Modules linked in:
| CPU: 0 PID: 87 Comm: kdevtmpfs Not tainted 4.1.16+ #5
| Hardware name: Hisilicon PhosphorHi1382 EVB (DT)
| task: ffffffc336591700 ti: ffffffc3365a4000 task.ti: ffffffc3365a4000
| PC is at dump_instr+0x68/0x100
| LR is at do_undefinstr+0x1d4/0x2a4
| pc : [] lr : [] pstate: 604001c5
| sp : ffffffc3365a6450

Reported-by: Hanjun Guo 
Tested-by: Xuefeng Wang 
Signed-off-by: James Morse 
Signed-off-by: Will Deacon 
Signed-off-by: Greg Kroah-Hartman

powerpc/mm: Fixup preempt underflow with huge pages

2016-04-20T06:41:53+00:00

commit 08a5bb2921e490939f78f38fd0d02858bb709942 upstream.

hugepd_free() used __get_cpu_var() once. Nothing ensured that the code
accessing the variable did not migrate from one CPU to another and soon
this was noticed by Tiejun Chen in 94b09d755462 ("powerpc/hugetlb:
Replace __get_cpu_var with get_cpu_var"). So we had it fixed.

Christoph Lameter was doing his __get_cpu_var() replaces and forgot
PowerPC. Then he noticed this and sent his fixed up batch again which
got applied as 69111bac42f5 ("powerpc: Replace __get_cpu_var uses").

The careful reader will noticed one little detail: get_cpu_var() got
replaced with this_cpu_ptr(). So now we have a put_cpu_var() which does
a preempt_enable() and nothing that does preempt_disable() so we
underflow the preempt counter.

Cc: Benjamin Herrenschmidt 
Cc: Christoph Lameter 
Signed-off-by: Sebastian Andrzej Siewior 
Reviewed-by: Aneesh Kumar K.V 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman