linux-stable.git/arch/mips, branch v3.4.91

MIPS: Hibernate: Flush TLB entries in swsusp_arch_resume()

2014-05-13T12:11:29+00:00

commit c14af233fbe279d0e561ecf84f1208b1bae087ef upstream.

The original MIPS hibernate code flushes cache and TLB entries in
swsusp_arch_resume(). But they are removed in Commit 44eeab67416711
(MIPS: Hibernation: Remove SMP TLB and cacheflushing code.). A cross-
CPU flush is surely unnecessary because all but the local CPU have
already been disabled. But a local flush (at least the TLB flush) is
needed. When we do hibernation on Loongson-3 with an E1000E NIC, it is
very easy to produce a kernel panic (kernel page fault, or unaligned
access). The root cause is E1000E driver use vzalloc_node() to allocate
pages, the stale TLB entries of the booting kernel will be misused by
the resumed target kernel.

Signed-off-by: Huacai Chen 
Cc: John Crispin 
Cc: Steven J. Hill 
Cc: Aurelien Jarno 
Cc: linux-mips@linux-mips.org
Cc: Fuxin Zhang 
Cc: Zhangjin Wu 
Patchwork: https://patchwork.linux-mips.org/patch/6643/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

compiler/gcc4: Add quirk for 'asm goto' miscompilation bug

2014-04-14T13:44:16+00:00

commit 3f0116c3238a96bc18ad4b4acefe4e7be32fa861 upstream.

Fengguang Wu, Oleg Nesterov and Peter Zijlstra tracked down
a kernel crash to a GCC bug: GCC miscompiles certain 'asm goto'
constructs, as outlined here:

  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670

Implement a workaround suggested by Jakub Jelinek.

Reported-and-tested-by: Fengguang Wu 
Reported-by: Oleg Nesterov 
Reported-by: Peter Zijlstra 
Suggested-by: Jakub Jelinek 
Reviewed-by: Richard Henderson 
Cc: Linus Torvalds 
Cc: Andrew Morton 
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings 
[hq: Backported to 3.4: Adjust context]
Signed-off-by: Qiang Huang 
Cc: Li Zefan 
Cc: Jianguo Wu 
Signed-off-by: Greg Kroah-Hartman

MIPS: DMA: For BMIPS5000 cores flush region just like non-coherent R10000

2013-12-20T15:34:19+00:00

commit f86f55d3ad21b21b736bdeb29bee0f0937b77138 upstream.

The BMIPS5000 (Zephyr) processor utilizes instruction speculation. A
stale misprediction address in either the JTB or the CRS may trigger
a prefetch inside a region that is currently being used by a DMA engine,
which is not IO-coherent.  This prefetch will fetch a line into the
scache, and that line will soon become stale (ie wrong) during/after the
DMA.  Mayhem ensues.

In dma-default.c, the r10000 is handled as a special case in the same way
that we want to handle Zephyr.  So we generalize the exception cases into
a function, and include Zephyr as one of the processors that needs this
special care.

Signed-off-by: Jim Quinlan 
Cc: linux-mips@linux-mips.org
Cc: cernekee@gmail.com
Patchwork: https://patchwork.linux-mips.org/patch/5776/
Signed-off-by: Ralf Baechle 
Cc: John Ulvr 
Signed-off-by: Greg Kroah-Hartman

MIPS: ath79: Fix ar933x watchdog clock

2013-09-27T00:15:50+00:00

commit a1191927ace7e6f827132aa9e062779eb3f11fa5 upstream.

The watchdog device on the AR933x is connected to
the AHB clock, however the current code uses the
reference clock. Due to the wrong rate, the watchdog
driver can't calculate correct register values for
a given timeout value and the watchdog unexpectedly
restarts the system.

The code uses the wrong value since the initial
commit 04225e1d227c8e68d685936ecf42ac175fec0e54
(MIPS: ath79: add AR933X specific clock init)

The patch fixes the code to use the correct clock
rate to avoid the problem.

Signed-off-by: Felix Fietkau 
Signed-off-by: Gabor Juhos 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5777/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: Rewrite pfn_valid to work in modules, too.

2013-08-20T15:26:28+00:00

Upstream commit 8b9232141bf40788cce31f893c13f344ec31ee66.

This fixes:

  MODPOST 393 modules
ERROR: "min_low_pfn" [arch/mips/kvm/kvm.ko] undefined!
make[3]: *** [__modpost] Error 1

It would have been possible to just export min_low_pfn but in the end
pfn_valid should return 1 for any pfn argument for which a struct page
exists so using min_low_pfn was wrong anyway.

[Backport to 3.4 kernel. Applies cleanly on top of current 3.4 patch queue,
and fixes "make ARCH=mips allmodconfig; make ARCH=mips" build problem. - Guenter]

Signed-off-by: Ralf Baechle 
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

MIPS: Expose missing pci_io{map,unmap} declarations

2013-08-20T15:26:27+00:00

commit 78857614104a26cdada4c53eea104752042bf5a1 upstream.

The GENERIC_PCI_IOMAP does not depend on CONFIG_PCI so move
it to the CONFIG_MIPS symbol so it's always selected for MIPS.
This fixes the missing pci_iomap declaration for MIPS.
Moreover, the pci_iounmap function was not defined in the
io.h header file if the CONFIG_PCI symbol is not set,
but it should since MIPS is not using CONFIG_GENERIC_IOMAP.

This fixes the following problem on a allyesconfig:

drivers/net/ethernet/3com/3c59x.c:1031:2: error: implicit declaration of
function 'pci_iomap' [-Werror=implicit-function-declaration]
drivers/net/ethernet/3com/3c59x.c:1044:3: error: implicit declaration of
function 'pci_iounmap' [-Werror=implicit-function-declaration]

Signed-off-by: Markos Chandras 
Acked-by: Steven J. Hill 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5478/
Signed-off-by: Ralf Baechle 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix poweroff failure when HOTPLUG_CPU configured.

2013-01-17T16:50:42+00:00

commit 8add1ecb81f541ef2fcb0b85a5470ad9ecfb4a84 upstream.

When poweroff machine, kernel_power_off() call disable_nonboot_cpus().
And if we have HOTPLUG_CPU configured, disable_nonboot_cpus() is not an
empty function but attempt to actually disable the nonboot cpus. Since
system state is SYSTEM_POWER_OFF, play_dead() won't be called and thus
disable_nonboot_cpus() hangs. Therefore, we make this patch to avoid
poweroff failure.

Signed-off-by: Huacai Chen 
Signed-off-by: Hongliang Tao 
Signed-off-by: Hua Yan 
Cc: Yong Zhang 
Cc: Fuxin Zhang 
Cc: Zhangjin Wu 
Patchwork: https://patchwork.linux-mips.org/patch/4211/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

mips,kgdb: fix recursive page fault with CONFIG_KPROBES

2012-10-21T16:27:57+00:00

commit f0a996eeeda214f4293e234df33b29bec003b536 upstream.

This fault was detected using the kgdb test suite on boot and it
crashes recursively due to the fact that CONFIG_KPROBES on mips adds
an extra die notifier in the page fault handler.  The crash signature
looks like this:

kgdbts:RUN bad memory access test
KGDB: re-enter exception: ALL breakpoints killed
Call Trace:
[<807b7548>] dump_stack+0x20/0x54
[<807b7548>] dump_stack+0x20/0x54

The fix for now is to have kgdb return immediately if the fault type
is DIE_PAGE_FAULT and allow the kprobe code to decide what is supposed
to happen.

Signed-off-by: Jason Wessel 
Cc: Masami Hiramatsu 
Cc: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

kbuild: Fix gcc -x syntax

2012-10-12T20:38:37+00:00

commit b1e0d8b70fa31821ebca3965f2ef8619d7c5e316 upstream.

The correct syntax for gcc -x is "gcc -x assembler", not
"gcc -xassembler". Even though the latter happens to work, the former
is what is documented in the manual page and thus what gcc wrappers
such as icecream do expect.

This isn't a cosmetic change. The missing space prevents icecream from
recognizing compilation tasks it can't handle, leading to silent kernel
miscompilations.

Besides me, credits go to Michael Matz and Dirk Mueller for
investigating the miscompilation issue and tracking it down to this
incorrect -x parameter syntax.

Signed-off-by: Jean Delvare 
Acked-by: Ingo Molnar 
Cc: Bernhard Walle 
Cc: Michal Marek 
Cc: Ralf Baechle 
Signed-off-by: Michal Marek 
Signed-off-by: Greg Kroah-Hartman

MIPS: mm: Add compound tail page _mapcount when mapped

2012-10-02T17:30:09+00:00

commit af89fa3986b9d034a286544ab1ed95096496a2f9 upstream.

See commit b6999b191 which did the same modification for x86's mm/gup,

Quote from commit b6999b191:
    "If compound pages are used and the page is a
    tail page, gup_huge_pmd() increases _mapcount to record tail page are
    mapped while gup_huge_pud does not do that."

[ralf@linux-mips.org: fixed rejects caused by the original patch getting
linewrapped.]

Signed-off-by: Jovi Zhang 
Cc: Youquan Song 
Cc: Andi Kleen 
Patchwork: https://patchwork.linux-mips.org/patch/4291/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman