linux-stable.git/arch, branch v3.4.58

x86, fpu: correct the asm constraints for fxsave, unbreak mxcsr.daz

2013-08-11T22:38:43+00:00

commit eaa5a990191d204ba0f9d35dbe5505ec2cdd1460 upstream.

GCC will optimize mxcsr_feature_mask_init in arch/x86/kernel/i387.c:

		memset(&fx_scratch, 0, sizeof(struct i387_fxsave_struct));
		asm volatile("fxsave %0" : : "m" (fx_scratch));
		mask = fx_scratch.mxcsr_mask;
		if (mask == 0)
			mask = 0x0000ffbf;

to

		memset(&fx_scratch, 0, sizeof(struct i387_fxsave_struct));
		asm volatile("fxsave %0" : : "m" (fx_scratch));
		mask = 0x0000ffbf;

since asm statement doesn’t say it will update fx_scratch.  As the
result, the DAZ bit will be cleared.  This patch fixes it. This bug
dates back to at least kernel 2.6.12.

Signed-off-by: H. Peter Anvin 
Signed-off-by: Greg Kroah-Hartman

s390: move dummy io_remap_pfn_range() to asm/pgtable.h

2013-08-04T08:26:03+00:00

commit 4f2e29031e6c67802e7370292dd050fd62f337ee upstream.

Commit b4cbb197c7e7 ("vm: add vm_iomap_memory() helper function") added
a helper function wrapper around io_remap_pfn_range(), and every other
architecture defined it in .

The s390 choice of  may make sense, but is not very convenient
for this case, and gratuitous differences like that cause unexpected errors like this:

   mm/memory.c: In function 'vm_iomap_memory':
   mm/memory.c:2439:2: error: implicit declaration of function 'io_remap_pfn_range' [-Werror=implicit-function-declaration]

Glory be the kbuild test robot who noticed this, bisected it, and
reported it to the guilty parties (ie me).

Signed-off-by: Linus Torvalds 
Cc: Martin Schwidefsky 
Cc: Heiko Carstens 
[bwh: Backported to 3.2: the macro was not defined, so this is an addition
 and not a move]
Signed-off-by: Ben Hutchings 
Signed-off-by: Greg Kroah-Hartman

powerpc/modules: Module CRC relocation fix causes perf issues

2013-08-04T08:25:55+00:00

commit 0e0ed6406e61434d3f38fb58aa8464ec4722b77e upstream.

Module CRCs are implemented as absolute symbols that get resolved by
a linker script. We build an intermediate .o that contains an
unresolved symbol for each CRC. genksysms parses this .o, calculates
the CRCs and writes a linker script that "resolves" the symbols to
the calculated CRC.

Unfortunately the ppc64 relocatable kernel sees these CRCs as symbols
that need relocating and relocates them at boot. Commit d4703aef
(module: handle ppc64 relocating kcrctabs when CONFIG_RELOCATABLE=y)
added a hook to reverse the bogus relocations. Part of this patch
created a symbol at 0x0:

# head -2 /proc/kallsyms
0000000000000000 T reloc_start
c000000000000000 T .__start

This reloc_start symbol is causing lots of confusion to perf. It
thinks reloc_start is a massive function that stretches from 0x0 to
0xc000000000000000 and we get various cryptic errors out of perf,
including:

problem incrementing symbol count, skipping event

This patch removes the  reloc_start linker script label and instead
defines it as PHYSICAL_START. We also need to wrap it with
CONFIG_PPC64 because the ppc32 kernel can set a non zero
PHYSICAL_START at compile time and we wouldn't want to subtract
it from the CRCs in that case.

Signed-off-by: Anton Blanchard 
Acked-by: Rusty Russell 
Signed-off-by: Benjamin Herrenschmidt 
Signed-off-by: Greg Kroah-Hartman

sparc: tsb must be flushed before tlb

2013-07-28T23:25:52+00:00

Upstream commit 23a01138efe216f8084cfaa74b0b90dd4b097441

This fixes a race where a cpu may re-load a tlb from a stale tsb right
after it has been flushed by a remote function call.

I still see some instability when stressing the system with parallel
kernel builds while creating memory pressure by writing to
/proc/sys/vm/nr_hugepages, but this patch improves the stability
significantly.

Signed-off-by: Dave Kleikamp 
Acked-by: Bob Picco 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sparc64 address-congruence property

2013-07-28T23:25:50+00:00

Upstream commit 771a37ff4d80b80db3b0df3e7696f14b298c67b7

The Machine Description (MD) property "address-congruence-offset" is
optional. According to the MD specification the value is assumed 0UL when
not present. This caused early boot failure on T5.

Signed-off-by: Bob Picco 
CC: sparclinux@vger.kernel.org
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

sparc32: vm_area_struct access for old Sun SPARCs.

2013-07-28T23:25:49+00:00

Upstream commit 961246b4ed8da3bcf4ee1eb9147f341013553e3c

Commit e4c6bfd2d79d063017ab19a18915f0bc759f32d9 ("mm: rearrange
vm_area_struct for fewer cache misses") changed the layout of the
vm_area_struct structure, it broke several SPARC32 assembly routines
which used numerical constants for accessing the vm_mm field.

This patch defines the VMA_VM_MM constant to replace the immediate values.

Signed-off-by: Olivier DANET 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ARM: 7765/1: perf: Record the user-mode PC in the call chain.

2013-07-22T01:19:02+00:00

commit c5f927a6f62196226915f12194c9d0df4e2210d7 upstream.

With this change, we no longer lose the innermost entry in the user-mode
part of the call chain.  See also the x86 port, which includes the ip.

It's possible to partially work around this problem by post-processing
the data to use the PERF_SAMPLE_IP value, but this works only if the CPU
wasn't in the kernel when the sample was taken.

Signed-off-by: Jed Davis 
Signed-off-by: Will Deacon 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman

xen/time: remove blocked time accounting from xen "clockchip"

2013-07-22T01:19:01+00:00

commit 0b0c002c340e78173789f8afaa508070d838cf3d upstream.

... because the "clock_event_device framework" already accounts for idle
time through the "event_handler" function pointer in
xen_timer_interrupt().

The patch is intended as the completion of [1]. It should fix the double
idle times seen in PV guests' /proc/stat [2]. It should be orthogonal to
stolen time accounting (the removed code seems to be isolated).

The approach may be completely misguided.

[1] https://lkml.org/lkml/2011/10/6/10
[2] http://lists.xensource.com/archives/html/xen-devel/2010-08/msg01068.html

John took the time to retest this patch on top of v3.10 and reported:
"idle time is correctly incremented for pv and hvm for the normal
case, nohz=off and nohz=idle." so lets put this patch in.

Signed-off-by: Laszlo Ersek 
Signed-off-by: John Haxby 
Signed-off-by: Konrad Rzeszutek Wilk 
Signed-off-by: Greg Kroah-Hartman

ARM: 7772/1: Fix missing flush_kernel_dcache_page() for noMMU

2013-07-03T17:59:00+00:00

commit 63384fd0b1509acf522a8a8fcede09087eedb7df upstream.

Commit 1bc3974 (ARM: 7755/1: handle user space mapped pages in
flush_kernel_dcache_page) moved the implementation of
flush_kernel_dcache_page() into mm/flush.c but did not implement it
on noMMU ARM.

Signed-off-by: Simon Baatz 
Acked-by: Kevin Hilman 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman

ARM: 7755/1: handle user space mapped pages in flush_kernel_dcache_page

2013-07-03T17:59:00+00:00

commit 1bc39742aab09248169ef9d3727c9def3528b3f3 upstream.

Commit f8b63c1 made flush_kernel_dcache_page a no-op assuming that
the pages it needs to handle are kernel mapped only.  However, for
example when doing direct I/O, pages with user space mappings may
occur.

Thus, continue to do lazy flushing if there are no user space
mappings.  Otherwise, flush the kernel cache lines directly.

Signed-off-by: Simon Baatz 
Reviewed-by: Catalin Marinas 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman