KVM: x86: Emulation of MOV-sreg to memory uses incorrect size

In x86, you can only MOV-sreg to memory with either 16-bits or 64-bits size.
In contrast, KVM may write to 32-bits memory on MOV-sreg. This patch fixes KVM
behavior, and sets the destination operand size to two, if the destination is
memory.

When destination is registers, and the operand size is 32-bits, the high
16-bits in modern CPUs is filled with zero.  This is handled correctly.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: SYSCALL cannot clear eflags[1]

SYSCALL emulation currently clears in 64-bit mode eflags according to
MSR_SYSCALL_MASK.  However, on bare-metal eflags[1] which is fixed to one
cannot be cleared, even if MSR_SYSCALL_MASK masks the bit.  This wrong behavior
may result in failed VM-entry, as VT disallows entry with eflags[1] cleared.

This patch sets the bit after masking eflags on syscall.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Wrong flags on CMPS and SCAS emulation

CMPS and SCAS instructions are evaluated in the wrong order.  For reference (of
CMPS), see http://www.fermimn.gov.it/linux/quarta/x86/cmps.htm : "Note that the
direction of subtraction for CMPS is [SI] - [DI] or [ESI] - [EDI]. The left
operand (SI or ESI) is the source and the right operand (DI or EDI) is the
destination. This is the reverse of the usual Intel convention in which the
left operand is the destination and the right operand is the source."

Introducing em_cmp_r for this matter that performs comparison in reverse order
using fastop infrastructure to avoid a wrapper function.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Emulate push sreg as done in Core

According to Intel SDM push of segment selectors is done in the following
manner: "if the operand size is 32-bits, either a zero-extended value is pushed
on the stack or the segment selector is written on the stack using a 16-bit
move. For the last case, all recent Core and Atom processors perform a 16-bit
move, leaving the upper portion of the stack location unmodified."

This patch modifies the behavior to match the core behavior.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: MOV to CR3 can set bit 63

Although Intel SDM mentions bit 63 is reserved, MOV to CR3 can have bit 63 set.
As Intel SDM states in section 4.10.4 "Invalidation of TLBs and
Paging-Structure Caches": " MOV to CR3. ... If CR4.PCIDE = 1 and bit 63 of the
instructionâ€™s source operand is 0 ..."

In other words, bit 63 is not reserved. KVM emulator currently consider bit 63
as reserved. Fix it.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Do not update EFLAGS on faulting emulation

If the emulation ends in fault, eflags should not be updated.  However, several
instruction emulations (actually all the fastops) currently update eflags, if
the fault was detected afterwards (e.g., #PF during writeback).

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Combine the lgdt and lidt emulation logic

LGDT and LIDT emulation logic is almost identical. Merge the logic into a
single point to avoid redundancy. This will be used by the next patch that
will ensure the bases of the loaded GDTR and IDTR are canonical.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Inject #GP when loading system segments with non-canonical base

When emulating LTR/LDTR/LGDT/LIDT, #GP should be injected if the base is
non-canonical. Otherwise, VM-entry will fail.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Remove redundant and incorrect cpl check on task-switch

Task-switch emulation checks the privilege level prior to performing the
task-switch.  This check is incorrect in the case of task-gates, in which the
tss.dpl is ignored, and can cause superfluous exceptions.  Moreover this check
is unnecassary, since the CPU checks the privilege levels prior to exiting.
Intel SDM 25.4.2 says "If CALL or JMP accesses a TSS descriptor directly
outside IA-32e mode, privilege levels are checked on the TSS descriptor" prior
to exiting.  AMD 15.14.1 says "The intercept is checked before the task switch
takes place but after the incoming TSS and task gate (if one was involved) have
been checked for correctness."

This patch removes the CPL checks for CALL and JMP.

Signed-off-by: Nadav Amit <namit@cs.technion.ac.il>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
arm64: ftrace: eliminate literal pool entries

Replace ldr xN, =<symbol> with adrp/add or adrp/ldr [as appropriate]
in the implementation of _mcount(), which may be called very often.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arm64: kvm: eliminate literal pool entries

Replace two instances of 'ldr xN, =(constant)' in the world switch
hot path with 'mov' instructions.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
of: Add bindings for nvidia,tegra124-soctherm

This adds binding documentation and headers for the Tegra124
SOCTHERM device tree node.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Eduardo Valentin <edubezval@gmail.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
ARM: tegra: Add soctherm and thermal zones to Tegra124 device tree

This adds the soctherm thermal sensing and management unit to the
Tegra124 device tree along with the four thermal zones corresponding
to the four thermal sensors provided by soctherm.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
ARM: tegra: Add thermal trip points for Jetson TK1

This adds critical trip points to the Jetson TK1 device tree.
The device will do a controlled shutdown when either the CPU, GPU
or MEM thermal zone reaches 101 degrees Celsius.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
thermal: Add Tegra SOCTHERM thermal management driver

This adds support for the Tegra SOCTHERM thermal sensing and management
system found in the Tegra124 system-on-chip. This initial driver supports
temperature polling for four thermal zones.

Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
Merge branch 'work-linus' into work-next

Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
HID: wacom - make sure touch_input is valid before using it

touch_input is stored in wacom_shared for pen data to report touch
switch status. It is possible, although we didn't see it happen on
Linux yet, that pen data is procesed before touch interface is
fully probed.

As a by-product of this patch, it fixes the FreeBSD issue reported
by Denis Akiyakov http://www.spinics.net/lists/linux-input/msg33971.html

Reviewed-by: Hans Petter Selasky <hps@selasky.org>
Tested-by: Denis Akiyakov <d.akiyakov@gmail.com>
Signed-off-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Merge branch 'for-3.19/wacom' into for-next
sysfs: driver core: Fix glue dir race condition by gdp_mutex

There is a race condition when removing glue directory.
It can be reproduced in following test:

path 1: Add first child device
device_add()
    get_device_parent()
            /*find parent from glue_dirs.list*/
            list_for_each_entry(k, &dev->class->p->glue_dirs.list, entry)
                    if (k->parent == parent_kobj) {
                            kobj = kobject_get(k);
                            break;
                    }
            ....
            class_dir_create_and_add()

path2: Remove last child device under glue dir
device_del()
    cleanup_device_parent()
            cleanup_glue_dir()
                    kobject_put(glue_dir);

If path2 has been called cleanup_glue_dir(), but not
call kobject_put(glue_dir), the glue dir is still
in parent's kset list. Meanwhile, path1 find the glue
dir from the glue_dirs.list. Path2 may release glue dir
before path1 call kobject_get(). So kernel will report
the warning and bug_on.

This is a "classic" problem we have of a kref in a list
that can be found while the last instance could be removed
at the same time.

This patch reuse gdp_mutex to fix this race condition.

The following calltrace is captured in kernel 3.4, but
the latest kernel still has this bug.

-----------------------------------------------------
<4>[ 3965.441471] WARNING: at ...include/linux/kref.h:41 kobject_get+0x33/0x40()
<4>[ 3965.441474] Hardware name: Romley
<4>[ 3965.441475] Modules linked in: isd_iop(O) isd_xda(O)...
...
<4>[ 3965.441605] Call Trace:
<4>[ 3965.441611]  [<ffffffff8103717a>] warn_slowpath_common+0x7a/0xb0
<4>[ 3965.441615]  [<ffffffff810371c5>] warn_slowpath_null+0x15/0x20
<4>[ 3965.441618]  [<ffffffff81215963>] kobject_get+0x33/0x40
<4>[ 3965.441624]  [<ffffffff812d1e45>] get_device_parent.isra.11+0x135/0x1f0
<4>[ 3965.441627]  [<ffffffff812d22d4>] device_add+0xd4/0x6d0
<4>[ 3965.441631]  [<ffffffff812d0dbc>] ? dev_set_name+0x3c/0x40
....
<2>[ 3965.441912] kernel BUG at ..../fs/sysfs/group.c:65!
<4>[ 3965.441915] invalid opcode: 0000 [#1] SMP
...
<4>[ 3965.686743]  [<ffffffff811a677e>] sysfs_create_group+0xe/0x10
<4>[ 3965.686748]  [<ffffffff810cfb04>] blk_trace_init_sysfs+0x14/0x20
<4>[ 3965.686753]  [<ffffffff811fcabb>] blk_register_queue+0x3b/0x120
<4>[ 3965.686756]  [<ffffffff812030bc>] add_disk+0x1cc/0x490
....
-------------------------------------------------------

Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Weng Meiling <wengmeiling.weng@huawei.com>
Cc: <stable@vger.kernel.org> #3.4+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: fsl_lpuart: Remove unneeded check for 'res'

'res' will be automatically checked inside devm_ioremap_resource(), so there is
no need to explicitly perform a NULL check.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Jingchang Lu <jingchang.lu@freescale.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>