linux-toradex.git/arch/arm, branch v4.4.108

ARM: dma-mapping: disallow dma_get_sgtable() for non-kernel managed memory

2017-12-25T13:22:13+00:00

[ Upstream commit 916a008b4b8ecc02fbd035cfb133773dba1ff3d7 ]

dma_get_sgtable() tries to create a scatterlist table containing valid
struct page pointers for the coherent memory allocation passed in to it.

However, memory can be declared via dma_declare_coherent_memory(), or
via other reservation schemes which means that coherent memory is not
guaranteed to be backed by struct pages.  In such cases, the resulting
scatterlist table contains pointers to invalid pages, which causes
kernel oops later.

This patch adds detection of such memory, and refuses to create a
scatterlist table for such memory.

Reported-by: Shuah Khan 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARM: dts: am335x-evmsk: adjust mmc2 param to allow suspend

2017-12-25T13:22:13+00:00

[ Upstream commit 9bcf53f34a2c1cebc45cc12e273dcd5f51fbc099 ]

mmc2 used for wl12xx was missing the keep-power-in suspend
parameter. As a result the board couldn't reach suspend state.

Signed-off-by: Eyal Reizer 
Signed-off-by: Tony Lindgren 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARM: dts: ti: fix PCI bus dtc warnings

2017-12-25T13:22:11+00:00

[ Upstream commit 7d79f6098d82f8c09914d7799bc96891ad9c3baf ]

dtc recently added PCI bus checks. Fix these warnings.

Signed-off-by: Rob Herring 
Cc: "Benoît Cousson" 
Cc: Tony Lindgren 
Cc: linux-omap@vger.kernel.org
Signed-off-by: Tony Lindgren 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

arm: kprobes: Align stack to 8-bytes in test code

2017-12-25T13:22:10+00:00

[ Upstream commit 974310d047f3c7788a51d10c8d255eebdb1fa857 ]

kprobes test cases need to have a stack that is aligned to an 8-byte
boundary because they call other functions (and the ARM ABI mandates
that alignment) and because test cases include 64-bit accesses to the
stack. Unfortunately, GCC doesn't ensure this alignment for inline
assembler and for the code in question seems to always misalign it by
pushing just the LR register onto the stack. We therefore need to
explicitly perform stack alignment at the start of each test case.

Without this fix, some test cases will generate alignment faults on
systems where alignment is enforced. Even if the kernel is configured to
handle these faults in software, triggering them is ugly. It also
exposes limitations in the fault handling code which doesn't cope with
writes to the stack. E.g. when handling this instruction

   strd r6, [sp, #-64]!

the fault handling code will write to a stack location below the SP
value at the point the fault occurred, which coincides with where the
exception handler has pushed the saved register context. This results in
corruption of those registers.

Signed-off-by: Jon Medhurst 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

arm: kprobes: Fix the return address of multiple kretprobes

2017-12-25T13:22:10+00:00

[ Upstream commit 06553175f585b52509c7df37d6f4a50aacb7b211 ]

This is arm port of commit 737480a0d525 ("kprobes/x86:
Fix the return address of multiple kretprobes").

Fix the return address of subsequent kretprobes when multiple
kretprobes are set on the same function.

For example:

  # cd /sys/kernel/debug/tracing
  # echo "r:event1 sys_symlink" > kprobe_events
  # echo "r:event2 sys_symlink" >> kprobe_events
  # echo 1 > events/kprobes/enable
  # ln -s /tmp/foo /tmp/bar

 (without this patch)

  # cat trace | grep -v ^#
              ln-82    [000] dn.2    68.446525: event1: (kretprobe_trampoline+0x0/0x18 <- SyS_symlink)
              ln-82    [000] dn.2    68.447831: event2: (ret_fast_syscall+0x0/0x1c <- SyS_symlink)

 (with this patch)

  # cat trace | grep -v ^#
              ln-81    [000] dn.1    39.463469: event1: (ret_fast_syscall+0x0/0x1c <- SyS_symlink)
              ln-81    [000] dn.1    39.464701: event2: (ret_fast_syscall+0x0/0x1c <- SyS_symlink)

Signed-off-by: Masami Hiramatsu 
Cc: KUMANO Syuhei 
Signed-off-by: Jon Medhurst 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARM: Hide finish_arch_post_lock_switch() from modules

2017-12-25T13:22:09+00:00

commit ef0491ea17f8019821c7e9c8e801184ecf17f85a upstream.

The introduction of switch_mm_irqs_off() brought back an old bug
regarding the use of preempt_enable_no_resched:

As part of:

  62b94a08da1b ("sched/preempt: Take away preempt_enable_no_resched() from modules")

the definition of preempt_enable_no_resched() is only available in
built-in code, not in loadable modules, so we can't generally use
it from header files.

However, the ARM version of finish_arch_post_lock_switch()
calls preempt_enable_no_resched() and is defined as a static
inline function in asm/mmu_context.h. This in turn means we cannot
include asm/mmu_context.h from modules.

With today's tip tree, asm/mmu_context.h gets included from
linux/mmu_context.h, which is normally the exact pattern one would
expect, but unfortunately, linux/mmu_context.h can be included from
the vhost driver that is a loadable module, now causing this compile
time error with modular configs:

  In file included from ../include/linux/mmu_context.h:4:0,
                   from ../drivers/vhost/vhost.c:18:
  ../arch/arm/include/asm/mmu_context.h: In function 'finish_arch_post_lock_switch':
  ../arch/arm/include/asm/mmu_context.h:88:3: error: implicit declaration of function 'preempt_enable_no_resched' [-Werror=implicit-function-declaration]
     preempt_enable_no_resched();

Andy already tried to fix the bug by including linux/preempt.h
from asm/mmu_context.h, but that didn't help. Arnd suggested reordering
the header files, which wasn't popular, so let's use this
workaround instead:

The finish_arch_post_lock_switch() definition is now also hidden
inside of #ifdef MODULE, so we don't see anything referencing
preempt_enable_no_resched() from a header file. I've built a
few hundred randconfig kernels with this, and did not see any
new problems.

Tested-by: Guenter Roeck 
Signed-off-by: Steven Rostedt 
Signed-off-by: Arnd Bergmann 
Acked-by: Russell King 
Cc: Alexander Shishkin 
Cc: Andy Lutomirski 
Cc: Andy Lutomirski 
Cc: Ard Biesheuvel 
Cc: Arnaldo Carvalho de Melo 
Cc: Borislav Petkov 
Cc: Frederic Weisbecker 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Mel Gorman 
Cc: Peter Zijlstra 
Cc: Russell King - ARM Linux 
Cc: Stephane Eranian 
Cc: Thomas Gleixner 
Cc: Vince Weaver 
Cc: linux-arm-kernel@lists.infradead.org
Fixes: f98db6013c55 ("sched/core: Add switch_mm_irqs_off() and use it in the scheduler")
Link: http://lkml.kernel.org/r/1463146234-161304-1-git-send-email-arnd@arndb.de
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

arm: KVM: Fix VTTBR_BADDR_MASK BUG_ON off-by-one

2017-12-16T09:33:57+00:00

commit 5553b142be11e794ebc0805950b2e8313f93d718 upstream.

VTTBR_BADDR_MASK is used to sanity check the size and alignment of the
VTTBR address. It seems to currently be off by one, thereby only
allowing up to 39-bit addresses (instead of 40-bit) and also
insufficiently checking the alignment. This patch fixes it.

This patch is the 32bit pendent of Kristina's arm64 fix, and
she deserves the actual kudos for pinpointing that one.

Fixes: f7ed45be3ba52 ("KVM: ARM: World-switch implementation")
Cc:  # 3.9
Reported-by: Kristina Martsenko 
Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Christoffer Dall 
Signed-off-by: Greg Kroah-Hartman

arm: KVM: Survive unknown traps from guests

2017-12-16T09:33:52+00:00

[ Upstream commit f050fe7a9164945dd1c28be05bf00e8cfb082ccf ]

Currently we BUG() if we see a HSR.EC value we don't recognise. As
configurable disables/enables are added to the architecture (controlled
by RES1/RES0 bits respectively), with associated synchronous exceptions,
it may be possible for a guest to trigger exceptions with classes that
we don't recognise.

While we can't service these exceptions in a manner useful to the guest,
we can avoid bringing down the host. Per ARM DDI 0406C.c, all currently
unallocated HSR EC encodings are reserved, and per ARM DDI
0487A.k_iss10775, page G6-4395, EC values within the range 0x00 - 0x2c
are reserved for future use with synchronous exceptions, and EC values
within the range 0x2d - 0x3f may be used for either synchronous or
asynchronous exceptions.

The patch makes KVM handle any unknown EC by injecting an UNDEFINED
exception into the guest, with a corresponding (ratelimited) warning in
the host dmesg. We could later improve on this with with a new (opt-in)
exit to the host userspace.

Cc: Dave Martin 
Cc: Suzuki K Poulose 
Reviewed-by: Christoffer Dall 
Signed-off-by: Mark Rutland 
Signed-off-by: Marc Zyngier 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARM: OMAP2+: Release device node after it is no longer needed.

2017-12-16T09:33:51+00:00

[ Upstream commit b92675d998a9fa37fe9e0e35053a95b4a23c158b ]

The device node returned by of_find_node_by_name() needs to be released
after it is no longer needed to avoid a device node leak.

Signed-off-by: Guenter Roeck 
Signed-off-by: Tony Lindgren 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ARM: OMAP2+: Fix device node reference counts

2017-12-16T09:33:51+00:00

[ Upstream commit 10e5778f54765c96fe0c8f104b7a030e5b35bc72 ]

After commit 0549bde0fcb1 ("of: fix of_node leak caused in
of_find_node_opts_by_path"), the following error may be
reported when running omap images.

OF: ERROR: Bad of_node_put() on /ocp@68000000
CPU: 0 PID: 0 Comm: swapper Not tainted 4.10.0-rc7-next-20170210 #1
Hardware name: Generic OMAP3-GP (Flattened Device Tree)
[] (unwind_backtrace) from [] (show_stack+0x10/0x14)
[] (show_stack) from [] (dump_stack+0x98/0xac)
[] (dump_stack) from [] (kobject_release+0x48/0x7c)
[] (kobject_release)
	from [] (of_find_node_by_name+0x74/0x94)
[] (of_find_node_by_name)
	from [] (omap3xxx_hwmod_is_hs_ip_block_usable+0x24/0x2c)
[] (omap3xxx_hwmod_is_hs_ip_block_usable) from
[] (omap3xxx_hwmod_init+0x180/0x274)
[] (omap3xxx_hwmod_init)
	from [] (omap3_init_early+0xa0/0x11c)
[] (omap3_init_early)
	from [] (omap3430_init_early+0x8/0x30)
[] (omap3430_init_early)
	from [] (setup_arch+0xc04/0xc34)
[] (setup_arch) from [] (start_kernel+0x68/0x38c)
[] (start_kernel) from [<8020807c>] (0x8020807c)

of_find_node_by_name() drops the reference to the passed device node.
The commit referenced above exposes this problem.

To fix the problem, use of_get_child_by_name() instead of
of_find_node_by_name(); of_get_child_by_name() does not drop
the reference count of passed device nodes. While semantically
different, we only look for immediate children of the passed
device node, so of_get_child_by_name() is a more appropriate
function to use anyway.

Release the reference to the device node obtained with
of_get_child_by_name() after it is no longer needed to avoid
another device node leak.

While at it, clean up the code and change the return type of
omap3xxx_hwmod_is_hs_ip_block_usable() to bool to match its use
and the return type of of_device_is_available().

Cc: Qi Hou 
Cc: Peter Rosin 
Cc: Rob Herring 
Signed-off-by: Guenter Roeck 
Signed-off-by: Tony Lindgren 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman