linux-stable.git/arch/arm/include/asm, branch v3.18.80

ARM: 8715/1: add a private asm/unaligned.h

2017-11-08T09:03:48+00:00

commit 1cce91dfc8f7990ca3aea896bfb148f240b12860 upstream.

The asm-generic/unaligned.h header provides two different implementations
for accessing unaligned variables: the access_ok.h version used when
CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is set pretends that all pointers
are in fact aligned, while the le_struct.h version convinces gcc that the
alignment of a pointer is '1', to make it issue the correct load/store
instructions depending on the architecture flags.

On ARMv5 and older, we always use the second version, to let the compiler
use byte accesses. On ARMv6 and newer, we currently use the access_ok.h
version, so the compiler can use any instruction including stm/ldm and
ldrd/strd that will cause an alignment trap. This trap can significantly
impact performance when we have to do a lot of fixups and, worse, has
led to crashes in the LZ4 decompressor code that does not have a trap
handler.

This adds an ARM specific version of asm/unaligned.h that uses the
le_struct.h/be_struct.h implementation unconditionally. This should lead
to essentially the same code on ARMv6+ as before, with the exception of
using regular load/store instructions instead of the trapping instructions
multi-register variants.

The crash in the LZ4 decompressor code was probably introduced by the
patch replacing the LZ4 implementation, commit 4e1a33b105dd ("lib: update
LZ4 compressor module"), so linux-4.11 and higher would be affected most.
However, we probably want to have this backported to all older stable
kernels as well, to help with the performance issues.

There are two follow-ups that I think we should also work on, but not
backport to stable kernels, first to change the asm-generic version of
the header to remove the ARM special case, and second to review all
other uses of CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS to see if they
might be affected by the same problem on ARM.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman

ARM: 8632/1: ftrace: fix syscall name matching

2017-08-11T16:30:16+00:00

[ Upstream commit 270c8cf1cacc69cb8d99dea812f06067a45e4609 ]

ARM has a few system calls (most notably mmap) for which the names of
the functions which are referenced in the syscall table do not match the
names of the syscall tracepoints.  As a consequence of this, these
tracepoints are not made available.  Implement
arch_syscall_match_sym_name to fix this and allow tracing even these
system calls.

Signed-off-by: Rabin Vincent 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

Revert "ARM: 8457/1: psci-smp is built only for SMP"

2017-04-22T05:14:58+00:00

This reverts commit dbcfee724255ae171af51aaa56d8c5b78342adc9 which is
commit be95485a0b8288a93402705730d3ea32f9f812b9 upstream.

Upstream commit be95485 (ARM: 8457/1: psci-smp is built only for SMP)
was intended to fix the build error for configs with CONFIG_SMP=n and
CONFIG_ARM_PSCI=y, but it end up introducing a build error when
cherry-picked on 3.18.y.

This patch resulted in redefinition of psci_init() and broke the
build for every build config in 3.18.y with CONFIG_SMP=n and
CONFIG_ARM_PSCI=y.

Signed-off-by: Amit Pundir 
Signed-off-by: Greg Kroah-Hartman

ARM: 8584/1: floppy: avoid gcc-6 warning

2017-04-18T05:55:45+00:00

commit dd665be0e243873343a28e18f9f345927b658daf upstream.

gcc-6.0 warns about comparisons between two identical expressions,
which is what we get in the floppy driver when writing to the FD_DOR
register:

drivers/block/floppy.c: In function 'set_dor':
drivers/block/floppy.c:810:44: error: self-comparison always evaluates to true [-Werror=tautological-compare]
   fd_outb(newdor, FD_DOR);

It would be nice to use a static inline function instead of the
macro, to avoid the warning, but we cannot do that because the
FD_DOR definition is incomplete at this point.

Adding a cast to (u32) is a harmless way to shut up the warning,
just not very nice.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman

ARM: 8617/1: dma: fix dma_max_pfn()

2016-12-23T14:41:28+00:00

[ Upstream commit d248220f0465b818887baa9829e691fe662b2c5e ]

Since commit 6ce0d2001692 ("ARM: dma: Use dma_pfn_offset for dma address translation"),
dma_to_pfn() already returns the PFN with the physical memory start offset
so we don't need to add it again.

This fixes USB mass storage lock-up problem on systems that can't do DMA
over the entire physical memory range (e.g.) Keystone 2 systems with 4GB RAM
can only do DMA over the first 2GB. [K2E-EVM].

What happens there is that without this patch SCSI layer sets a wrong
bounce buffer limit in scsi_calculate_bounce_limit() for the USB mass
storage device. dma_max_pfn() evaluates to 0x8fffff and bounce_limit
is set to 0x8fffff000 whereas maximum DMA'ble physical memory on Keystone 2
is 0x87fffffff. This results in non DMA'ble pages being given to the
USB controller and hence the lock-up.

NOTE: in the above case, USB-SCSI-device's dma_pfn_offset was showing as 0.
This should have really been 0x780000 as on K2e, LOWMEM_START is 0x80000000
and HIGHMEM_START is 0x800000000. DMA zone is 2GB so dma_max_pfn should be
0x87ffff. The incorrect dma_pfn_offset for the USB storage device is because
USB devices are not correctly inheriting the dma_pfn_offset from the
USB host controller. This will be fixed by a separate patch.

Fixes: 6ce0d2001692 ("ARM: dma: Use dma_pfn_offset for dma address translation")
Cc: stable@vger.kernel.org
Cc: Greg Kroah-Hartman 
Cc: Santosh Shilimkar 
Cc: Arnd Bergmann 
Cc: Olof Johansson 
Cc: Catalin Marinas 
Cc: Linus Walleij 
Reported-by: Grygorii Strashko 
Signed-off-by: Roger Quadros 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

ARM: 8579/1: mm: Fix definition of pmd_mknotpresent

2016-07-11T15:15:55+00:00

[ Upstream commit 56530f5d2ddc9b9fade7ef8db9cb886e9dc689b5 ]

Currently pmd_mknotpresent will use a zero entry to respresent an
invalidated pmd.

Unfortunately this definition clashes with pmd_none, thus it is
possible for a race condition to occur if zap_pmd_range sees pmd_none
whilst __split_huge_pmd_locked is running too with pmdp_invalidate
just called.

This patch fixes the race condition by modifying pmd_mknotpresent to
create non-zero faulting entries (as is done in other architectures),
removing the ambiguity with pmd_none.

[catalin.marinas@arm.com: using L_PMD_SECT_VALID instead of PMD_TYPE_SECT]

Fixes: 8d9625070073 ("ARM: mm: Transparent huge page support for LPAE systems.")
Cc:  # 3.11+
Reported-by: Kirill A. Shutemov 
Acked-by: Will Deacon 
Cc: Russell King 
Signed-off-by: Steve Capper 
Signed-off-by: Catalin Marinas 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

ARM: 8578/1: mm: ensure pmd_present only checks the valid bit

2016-07-11T15:11:03+00:00

[ Upstream commit 624531886987f0f1b5d01fb598034d039198e090 ]

In a subsequent patch, pmd_mknotpresent will clear the valid bit of the
pmd entry, resulting in a not-present entry from the hardware's
perspective. Unfortunately, pmd_present simply checks for a non-zero pmd
value and will therefore continue to return true even after a
pmd_mknotpresent operation. Since pmd_mknotpresent is only used for
managing huge entries, this is only an issue for the 3-level case.

This patch fixes the 3-level pmd_present implementation to take into
account the valid bit. For bisectability, the change is made before the
fix to pmd_mknotpresent.

[catalin.marinas@arm.com: comment update regarding pmd_mknotpresent patch]

Fixes: 8d9625070073 ("ARM: mm: Transparent huge page support for LPAE systems.")
Cc:  # 3.11+
Cc: Russell King 
Cc: Steve Capper 
Signed-off-by: Will Deacon 
Signed-off-by: Catalin Marinas 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

ARM: 8457/1: psci-smp is built only for SMP

2016-04-12T21:06:25+00:00

[ Upstream commit be95485a0b8288a93402705730d3ea32f9f812b9 ]

The PSCI SMP implementation is built only when both CONFIG_SMP and
CONFIG_ARM_PSCI are set, so a configuration that has the latter
but not the former can get a link error when it tries to call
psci_smp_available().

arch/arm/mach-tegra/built-in.o: In function `tegra114_cpuidle_init':
cpuidle-tegra114.c:(.init.text+0x52a): undefined reference to `psci_smp_available'

This corrects the #ifdef in the psci.h header file to match the
Makefile conditional we have for building that function.

Signed-off-by: Arnd Bergmann 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

ARM: 8320/1: fix integer overflow in ELF_ET_DYN_BASE

2015-05-17T23:11:57+00:00

[ Upstream commit 8defb3367fcd19d1af64c07792aade0747b54e0f ]

Usually ELF_ET_DYN_BASE is 2/3 of TASK_SIZE. With 3G/1G user/kernel
split this is not so, because 2*TASK_SIZE overflows 32 bits,
so the actual value of ELF_ET_DYN_BASE is:
	(2 * TASK_SIZE / 3) = 0x2a000000

When ASLR is disabled PIE binaries will load at ELF_ET_DYN_BASE address.
On 32bit platforms AddressSanitzer uses addresses [0x20000000 - 0x40000000]
for shadow memory [1]. So ASan doesn't work for PIE binaries when ASLR disabled
as it fails to map shadow memory.
Also after Kees's 'split ET_DYN ASLR from mmap ASLR' patchset PIE binaries
has a high chance of loading somewhere in between [0x2a000000 - 0x40000000]
even if ASLR enabled. This makes ASan with PIE absolutely incompatible.

Fix overflow by dividing TASK_SIZE prior to multiplying.
After this patch ELF_ET_DYN_BASE equals to (for CONFIG_VMSPLIT_3G=y):
	(TASK_SIZE / 3 * 2) = 0x7f555554

[1] https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerAlgorithm#Mapping

Signed-off-by: Andrey Ryabinin 
Reported-by: Maria Guseva 
Cc: stable@vger.kernel.org
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

arm64: KVM: Do not use pgd_index to index stage-2 pgd

2015-05-11T11:07:37+00:00

commit 04b8dc85bf4a64517e3cf20e409eeaa503b15cc1 upstream.

The kernel's pgd_index macro is designed to index a normal, page
sized array. KVM is a bit diffferent, as we can use concatenated
pages to have a bigger address space (for example 40bit IPA with
4kB pages gives us an 8kB PGD.

In the above case, the use of pgd_index will always return an index
inside the first 4kB, which makes a guest that has memory above
0x8000000000 rather unhappy, as it spins forever in a page fault,
whist the host happilly corrupts the lower pgd.

The obvious fix is to get our own kvm_pgd_index that does the right
thing(tm).

Tested on X-Gene with a hacked kvmtool that put memory at a stupidly
high address.

Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Christoffer Dall 
Signed-off-by: Shannon Zhao 
Signed-off-by: Sasha Levin