linux-toradex.git/arch, branch v4.1.12

sched/preempt, powerpc, kvm: Use need_resched() instead of should_resched()

2015-10-27T00:52:01+00:00

commit c56dadf39761a6157239cac39e3988998c994f98 upstream.

Function should_resched() is equal to (!preempt_count() && need_resched()).
In preemptive kernel preempt_count here is non-zero because of vc->lock.

Signed-off-by: Konstantin Khlebnikov 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Alexander Graf 
Cc: Boris Ostrovsky 
Cc: David Vrabel 
Cc: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Link: http://lkml.kernel.org/r/20150715095203.12246.72922.stgit@buzz
Signed-off-by: Ingo Molnar 
Cc: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman

arm64: Fix THP protection change logic

2015-10-27T00:51:59+00:00

commit 1a541b4e3cd6f5795022514114854b3e1345f24e upstream.

6910fa1 ("arm64: enable PTE type bit in the mask for pte_modify") fixes
a problem whereby a large block of PROT_NONE mapped memory is
incorrectly mapped as block descriptors when mprotect is called.

Unfortunately, a subtle bug was introduced by this fix to the THP logic.

If one mmaps a large block of memory, then faults it such that it is
collapsed into THPs; resulting calls to mprotect on this area of memory
will lead to incorrect table descriptors being written instead of block
descriptors. This is because pmd_modify calls pte_modify which is now
allowed to modify the type of the page table entry.

This patch reverts commit 6910fa16dbe142f6a0fd0fd7c249f9883ff7fc8a, and
fixes the problem it was trying to address by adjusting PAGE_NONE to
represent a table entry. Thus no change in pte type is required when
moving from PROT_NONE to a different protection.

Fixes: 6910fa16dbe1 ("arm64: enable PTE type bit in the mask for pte_modify")
Cc:  # 4.0+
Cc: Feng Kan 
Reported-by: Ganapatrao Kulkarni 
Tested-by: Ganapatrao Kulkarni 
Reviewed-by: Catalin Marinas 
[SteveC: backported 1a541b4e3cd6f5795022514114854b3e1345f24e to 4.1 and
 4.2 stable. Just one minor fix to second part to allow patch to apply
cleanly, no logic changed.]
Signed-off-by: Steve Capper 
Signed-off-by: Catalin Marinas 
Signed-off-by: Greg Kroah-Hartman

sched/preempt: Fix cond_resched_lock() and cond_resched_softirq()

2015-10-27T00:51:58+00:00

commit fe32d3cd5e8eb0f82e459763374aa80797023403 upstream.

These functions check should_resched() before unlocking spinlock/bh-enable:
preempt_count always non-zero => should_resched() always returns false.
cond_resched_lock() worked iff spin_needbreak is set.

This patch adds argument "preempt_offset" to should_resched().

preempt_count offset constants for that:

  PREEMPT_DISABLE_OFFSET  - offset after preempt_disable()
  PREEMPT_LOCK_OFFSET     - offset after spin_lock()
  SOFTIRQ_DISABLE_OFFSET  - offset after local_bh_distable()
  SOFTIRQ_LOCK_OFFSET     - offset after spin_lock_bh()

Signed-off-by: Konstantin Khlebnikov 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Alexander Graf 
Cc: Boris Ostrovsky 
Cc: David Vrabel 
Cc: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Paul Mackerras 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Fixes: bdb438065890 ("sched: Extract the basic add/sub preempt_count modifiers")
Link: http://lkml.kernel.org/r/20150715095204.12246.98268.stgit@buzz
Signed-off-by: Ingo Molnar 
Signed-off-by: Mike Galbraith 
Signed-off-by: Greg Kroah-Hartman

arm64: errata: use KBUILD_CFLAGS_MODULE for erratum #843419

2015-10-27T00:51:54+00:00

commit b6dd8e0719c0d2d01429639a11b7bc2677de240c upstream.

Commit df057cc7b4fa ("arm64: errata: add module build workaround for
erratum #843419") sets CFLAGS_MODULE to ensure that the large memory
model is used by the compiler when building kernel modules.

However, CFLAGS_MODULE is an environment variable and intended to be
overridden on the command line, which appears to be the case with the
Ubuntu kernel packaging system, so use KBUILD_CFLAGS_MODULE instead.

Cc: Ard Biesheuvel 
Fixes: df057cc7b4fa ("arm64: errata: add module build workaround for erratum #843419")
Reported-by: Dann Frazier 
Tested-by: Dann Frazier 
Signed-off-by: Will Deacon 
Signed-off-by: Greg Kroah-Hartman

crypto: sparc - initialize blkcipher.ivsize

2015-10-27T00:51:53+00:00

commit a66d7f724a96d6fd279bfbd2ee488def6b081bea upstream.

Some of the crypto algorithms write to the initialization vector,
but no space has been allocated for it. This clobbers adjacent memory.

Signed-off-by: Dave Kleikamp 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix console output for Fulong2e system

2015-10-22T21:43:27+00:00

commit fc2ca674470bbfe11d72a20a3f19fd3dc43bfca0 upstream.

Commit 3adeb2566b9b ("MIPS: Loongson: Improve LEFI firmware interface")
made the number of UARTs dynamic if LEFI_FIRMWARE_INTERFACE is configured.
Unfortunately, it did not initialize the number of UARTs if
LEFI_FIRMWARE_INTERFACE is not configured. As a result, the Fulong2e
system has no console.

Fixes: 3adeb2566b9b ("MIPS: Loongson: Improve LEFI firmware interface")
Acked-by: Huacai Chen 
Signed-off-by: Guenter Roeck 
Tested-by: Markos Chandras 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/11076/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

m68k: Define asmlinkage_protect

2015-10-22T21:43:25+00:00

commit 8474ba74193d302e8340dddd1e16c85cc4b98caf upstream.

Make sure the compiler does not modify arguments of syscall functions.
This can happen if the compiler generates a tailcall to another
function.  For example, without asmlinkage_protect sys_openat is compiled
into this function:

sys_openat:
	clr.l %d0
	move.w 18(%sp),%d0
	move.l %d0,16(%sp)
	jbra do_sys_open

Note how the fourth argument is modified in place, modifying the register
%d4 that gets restored from this stack slot when the function returns to
user-space.  The caller may expect the register to be unmodified across
system calls.

Signed-off-by: Andreas Schwab 
Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Greg Kroah-Hartman

arm64: readahead: fault retry breaks mmap file read random detection

2015-10-22T21:43:25+00:00

commit 569ba74a7ba69f46ce2950bf085b37fea2408385 upstream.

This is the arm64 portion of commit 45cac65b0fcd ("readahead: fault
retry breaks mmap file read random detection"), which was absent from
the initial port and has since gone unnoticed. The original commit says:

> .fault now can retry.  The retry can break state machine of .fault.  In
> filemap_fault, if page is miss, ra->mmap_miss is increased.  In the second
> try, since the page is in page cache now, ra->mmap_miss is decreased.  And
> these are done in one fault, so we can't detect random mmap file access.
>
> Add a new flag to indicate .fault is tried once.  In the second try, skip
> ra->mmap_miss decreasing.  The filemap_fault state machine is ok with it.

With this change, Mark reports that:

> Random read improves by 250%, sequential read improves by 40%, and
> random write by 400% to an eMMC device with dm crypto wrapped around it.

Cc: Shaohua Li 
Cc: Rik van Riel 
Cc: Wu Fengguang 
Signed-off-by: Mark Salyzyn 
Signed-off-by: Riley Andrews 
Signed-off-by: Will Deacon 
Signed-off-by: Greg Kroah-Hartman

arm64: ftrace: fix function_graph tracer panic

2015-10-22T21:43:25+00:00

commit ee556d00cf20012e889344a0adbbf809ab5015a3 upstream.

When function graph tracer is enabled, the following operation
will trigger panic:

mount -t debugfs nodev /sys/kernel
echo next_tgid > /sys/kernel/tracing/set_ftrace_filter
echo function_graph > /sys/kernel/tracing/current_tracer
ls /proc/

------------[ cut here ]------------
[  198.501417] Unable to handle kernel paging request at virtual address cb88537fdc8ba316
[  198.506126] pgd = ffffffc008f79000
[  198.509363] [cb88537fdc8ba316] *pgd=00000000488c6003, *pud=00000000488c6003, *pmd=0000000000000000
[  198.517726] Internal error: Oops: 94000005 [#1] SMP
[  198.518798] Modules linked in:
[  198.520582] CPU: 1 PID: 1388 Comm: ls Tainted: G
[  198.521800] Hardware name: linux,dummy-virt (DT)
[  198.522852] task: ffffffc0fa9e8000 ti: ffffffc0f9ab0000 task.ti: ffffffc0f9ab0000
[  198.524306] PC is at next_tgid+0x30/0x100
[  198.525205] LR is at return_to_handler+0x0/0x20
[  198.526090] pc : [] lr : [] pstate: 60000145
[  198.527392] sp : ffffffc0f9ab3d40
[  198.528084] x29: ffffffc0f9ab3d40 x28: ffffffc0f9ab0000
[  198.529406] x27: ffffffc000d6a000 x26: ffffffc000b786e8
[  198.530659] x25: ffffffc0002a1900 x24: ffffffc0faf16c00
[  198.531942] x23: ffffffc0f9ab3ea0 x22: 0000000000000002
[  198.533202] x21: ffffffc000d85050 x20: 0000000000000002
[  198.534446] x19: 0000000000000002 x18: 0000000000000000
[  198.535719] x17: 000000000049fa08 x16: ffffffc000242efc
[  198.537030] x15: 0000007fa472b54c x14: ffffffffff000000
[  198.538347] x13: ffffffc0fada84a0 x12: 0000000000000001
[  198.539634] x11: ffffffc0f9ab3d70 x10: ffffffc0f9ab3d70
[  198.540915] x9 : ffffffc0000907c0 x8 : ffffffc0f9ab3d40
[  198.542215] x7 : 0000002e330f08f0 x6 : 0000000000000015
[  198.543508] x5 : 0000000000000f08 x4 : ffffffc0f9835ec0
[  198.544792] x3 : cb88537fdc8ba316 x2 : cb88537fdc8ba306
[  198.546108] x1 : 0000000000000002 x0 : ffffffc000d85050
[  198.547432]
[  198.547920] Process ls (pid: 1388, stack limit = 0xffffffc0f9ab0020)
[  198.549170] Stack: (0xffffffc0f9ab3d40 to 0xffffffc0f9ab4000)
[  198.582568] Call trace:
[  198.583313] [] next_tgid+0x30/0x100
[  198.584359] [] ftrace_graph_caller+0x6c/0x70
[  198.585503] [] ftrace_graph_caller+0x6c/0x70
[  198.586574] [] ftrace_graph_caller+0x6c/0x70
[  198.587660] [] ftrace_graph_caller+0x6c/0x70
[  198.588896] Code: aa0003f5 2a0103f4 b4000102 91004043 (885f7c60)
[  198.591092] ---[ end trace 6a346f8f20949ac8 ]---

This is because when using function graph tracer, if the traced
function return value is in multi regs ([x0-x7]), return_to_handler
may corrupt them. So in return_to_handler, the parameter regs should
be protected properly.

Signed-off-by: Li Bin 
Acked-by: AKASHI Takahiro 
Signed-off-by: Catalin Marinas 
Signed-off-by: Greg Kroah-Hartman

arm64/efi: Fix boot crash by not padding between EFI_MEMORY_RUNTIME regions

2015-10-22T21:43:25+00:00

commit 0ce3cc008ec04258b6a6314b09f1a6012810881a upstream.

The new Properties Table feature introduced in UEFIv2.5 may
split memory regions that cover PE/COFF memory images into
separate code and data regions. Since these regions only differ
in the type (runtime code vs runtime data) and the permission
bits, but not in the memory type attributes (UC/WC/WT/WB), the
spec does not require them to be aligned to 64 KB.

Since the relative offset of PE/COFF .text and .data segments
cannot be changed on the fly, this means that we can no longer
pad out those regions to be mappable using 64 KB pages.
Unfortunately, there is no annotation in the UEFI memory map
that identifies data regions that were split off from a code
region, so we must apply this logic to all adjacent runtime
regions whose attributes only differ in the permission bits.

So instead of rounding each memory region to 64 KB alignment at
both ends, only round down regions that are not directly
preceded by another runtime region with the same type
attributes. Since the UEFI spec does not mandate that the memory
map be sorted, this means we also need to sort it first.

Note that this change will result in all EFI_MEMORY_RUNTIME
regions whose start addresses are not aligned to the OS page
size to be mapped with executable permissions (i.e., on kernels
compiled with 64 KB pages). However, since these mappings are
only active during the time that UEFI Runtime Services are being
invoked, the window for abuse is rather small.

Tested-by: Mark Salter 
Tested-by: Mark Rutland  [UEFI 2.4 only]
Signed-off-by: Ard Biesheuvel 
Signed-off-by: Matt Fleming 
Reviewed-by: Mark Salter 
Reviewed-by: Mark Rutland 
Cc: Catalin Marinas 
Cc: Leif Lindholm 
Cc: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Cc: linux-kernel@vger.kernel.org
Link: http://lkml.kernel.org/r/1443218539-7610-3-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman