Commit Graph

4043 Commits

Author SHA1 Message Date
Steve Capper
bb95f1caee arm64: Initialise high_memory global variable earlier
commit f24e5834a2 upstream.

The high_memory global variable is used by
cma_declare_contiguous(.) before it is defined.

We don't notice this as we compute __pa(high_memory - 1), and it looks
like we're processing a VA from the direct linear map.

This problem becomes apparent when we flip the kernel virtual address
space and the linear map is moved to the bottom of the kernel VA space.

This patch moves the initialisation of high_memory before it used.

Fixes: f7426b983a ("mm: cma: adjust address limit to avoid hitting low/high memory boundary")
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-25 14:23:36 +01:00
Nick Desaulniers
b7ada2c0ea arm64: prevent regressions in compressed kernel image size when upgrading to binutils 2.27
[ Upstream commit fd9dde6abc ]

Upon upgrading to binutils 2.27, we found that our lz4 and gzip
compressed kernel images were significantly larger, resulting is 10ms
boot time regressions.

As noted by Rahul:
"aarch64 binaries uses RELA relocations, where each relocation entry
includes an addend value. This is similar to x86_64.  On x86_64, the
addend values are also stored at the relocation offset for relative
relocations. This is an optimization: in the case where code does not
need to be relocated, the loader can simply skip processing relative
relocations.  In binutils-2.25, both bfd and gold linkers did this for
x86_64, but only the gold linker did this for aarch64.  The kernel build
here is using the bfd linker, which stored zeroes at the relocation
offsets for relative relocations.  Since a set of zeroes compresses
better than a set of non-zero addend values, this behavior was resulting
in much better lz4 compression.

The bfd linker in binutils-2.27 is now storing the actual addend values
at the relocation offsets. The behavior is now consistent with what it
does for x86_64 and what gold linker does for both architectures.  The
change happened in this upstream commit:
https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=1f56df9d0d5ad89806c24e71f296576d82344613
Since a bunch of zeroes got replaced by non-zero addend values, we see
the side effect of lz4 compressed image being a bit bigger.

To get the old behavior from the bfd linker, "--no-apply-dynamic-relocs"
flag can be used:
$ LDFLAGS="--no-apply-dynamic-relocs" make
With this flag, the compressed image size is back to what it was with
binutils-2.25.

If the kernel is using ASLR, there aren't additional runtime costs to
--no-apply-dynamic-relocs, as the relocations will need to be applied
again anyway after the kernel is relocated to a random address.

If the kernel is not using ASLR, then presumably the current default
behavior of the linker is better. Since the static linker performed the
dynamic relocs, and the kernel is not moved to a different address at
load time, it can skip applying the relocations all over again."

Some measurements:

$ ld -v
GNU ld (binutils-2.25-f3d35cf6) 2.25.51.20141117
                    ^
$ ls -l vmlinux
-rwxr-x--- 1 ndesaulniers eng 300652760 Oct 26 11:57 vmlinux
$ ls -l Image.lz4-dtb
-rw-r----- 1 ndesaulniers eng 16932627 Oct 26 11:57 Image.lz4-dtb

$ ld -v
GNU ld (binutils-2.27-53dd00a1) 2.27.0.20170315
                    ^
pre patch:
$ ls -l vmlinux
-rwxr-x--- 1 ndesaulniers eng 300376208 Oct 26 11:43 vmlinux
$ ls -l Image.lz4-dtb
-rw-r----- 1 ndesaulniers eng 18159474 Oct 26 11:43 Image.lz4-dtb

post patch:
$ ls -l vmlinux
-rwxr-x--- 1 ndesaulniers eng 300376208 Oct 26 12:06 vmlinux
$ ls -l Image.lz4-dtb
-rw-r----- 1 ndesaulniers eng 16932466 Oct 26 12:06 Image.lz4-dtb

By Siqi's measurement w/ gzip:
binutils 2.27 with this patch (with --no-apply-dynamic-relocs):
Image 41535488
Image.gz 13404067

binutils 2.27 without this patch (without --no-apply-dynamic-relocs):
Image 41535488
Image.gz 14125516

Any compression scheme should be able to get better results from the
longer runs of zeros, not just GZIP and LZ4.

10ms boot time savings isn't anything to get excited about, but users of
arm64+compression+bfd-2.27 should not have to pay a penalty for no
runtime improvement.

Reported-by: Gopinath Elanchezhian <gelanchezhian@google.com>
Reported-by: Sindhuri Pentyala <spentyala@google.com>
Reported-by: Wei Wang <wvw@google.com>
Suggested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Suggested-by: Rahul Chaudhry <rahulchaudhry@google.com>
Suggested-by: Siqi Lin <siqilin@google.com>
Suggested-by: Stephen Hines <srhines@google.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: added comment to Makefile]
Signed-off-by: Will Deacon <will.deacon@arm.com>

Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:07:31 +01:00
Mark Rutland
aafb72d2ed arm64: KVM: Survive unknown traps from guests
[ Upstream commit ba4dd156ea ]

Currently we BUG() if we see an ESR_EL2.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 0487A.k_iss10775, page
D7-1937, 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 <dave.martin@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:28:19 +01:00
Dave Martin
a39224199e arm64: fpsimd: Prevent registers leaking from dead tasks
commit 071b6d4a5d upstream.

Currently, loading of a task's fpsimd state into the CPU registers
is skipped if that task's state is already present in the registers
of that CPU.

However, the code relies on the struct fpsimd_state * (and by
extension struct task_struct *) to unambiguously identify a task.

There is a particular case in which this doesn't work reliably:
when a task exits, its task_struct may be recycled to describe a
new task.

Consider the following scenario:

 1) Task P loads its fpsimd state onto cpu C.
        per_cpu(fpsimd_last_state, C) := P;
        P->thread.fpsimd_state.cpu := C;

 2) Task X is scheduled onto C and loads its fpsimd state on C.
        per_cpu(fpsimd_last_state, C) := X;
        X->thread.fpsimd_state.cpu := C;

 3) X exits, causing X's task_struct to be freed.

 4) P forks a new child T, which obtains X's recycled task_struct.
	T == X.
	T->thread.fpsimd_state.cpu == C (inherited from P).

 5) T is scheduled on C.
	T's fpsimd state is not loaded, because
	per_cpu(fpsimd_last_state, C) == T (== X) &&
	T->thread.fpsimd_state.cpu == C.

        (This is the check performed by fpsimd_thread_switch().)

So, T gets X's registers because the last registers loaded onto C
were those of X, in (2).

This patch fixes the problem by ensuring that the sched-in check
fails in (5): fpsimd_flush_task_state(T) is called when T is
forked, so that T->thread.fpsimd_state.cpu == C cannot be true.
This relies on the fact that T is not schedulable until after
copy_thread() completes.

Once T's fpsimd state has been loaded on some CPU C there may still
be other cpus D for which per_cpu(fpsimd_last_state, D) ==
&X->thread.fpsimd_state.  But D is necessarily != C in this case,
and the check in (5) must fail.

An alternative fix would be to do refcounting on task_struct.  This
would result in each CPU holding a reference to the last task whose
fpsimd state was loaded there.  It's not clear whether this is
preferable, and it involves higher overhead than the fix proposed
in this patch.  It would also move all the task_struct freeing
work into the context switch critical section, or otherwise some
deferred cleanup mechanism would need to be introduced, neither of
which seems obviously justified.

Fixes: 005f78cd88 ("arm64: defer reloading a task's FPSIMD state to userland resume")
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: word-smithed the comment so it makes more sense]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:28:14 +01:00
Kristina Martsenko
63fba9ff76 arm64: KVM: fix VTTBR_BADDR_MASK BUG_ON off-by-one
commit 26aa7b3b1c 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 47-bit addresses (instead of 48-bit) and also
insufficiently checking the alignment. This patch fixes it.

As an example, with 4k pages, before this patch we have:

  PHYS_MASK_SHIFT = 48
  VTTBR_X = 37 - 24 = 13
  VTTBR_BADDR_SHIFT = 13 - 1 = 12
  VTTBR_BADDR_MASK = ((1 << 35) - 1) << 12 = 0x00007ffffffff000

Which is wrong, because the mask doesn't allow bit 47 of the VTTBR
address to be set, and only requires the address to be 12-bit (4k)
aligned, while it actually needs to be 13-bit (8k) aligned because we
concatenate two 4k tables.

With this patch, the mask becomes 0x0000ffffffffe000, which is what we
want.

Fixes: 0369f6a34b ("arm64: KVM: EL2 register definitions")
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:28:14 +01:00
Catalin Marinas
e5380004ee arm64: Implement arch-specific pte_access_permitted()
commit 6218f96c58 upstream.

The generic pte_access_permitted() implementation only checks for
pte_present() (together with the write permission where applicable).
However, for both kernel ptes and PROT_NONE mappings pte_present() also
returns true on arm64 even though such mappings are not user accessible.
Additionally, arm64 now supports execute-only user permission
(PROT_EXEC) which is implemented by clearing the PTE_USER bit.

With this patch the arm64 implementation of pte_access_permitted()
checks for the PTE_VALID and PTE_USER bits together with writable access
if applicable.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-30 08:39:01 +00:00
Jon Mason
5d820f84e1 arm64: dts: NS2: reserve memory for Nitro firmware
[ Upstream commit 0cc878d678 ]

Nitro firmware is loaded into memory by the bootloader at a specific
location.  Set this memory range aside to prevent the kernel from using
it.

Signed-off-by: Jon Mason <jon.mason@broadcom.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-21 09:23:26 +01:00
Will Deacon
dea9c75f3f arm64: dma-mapping: Only swizzle DMA ops for IOMMU_DOMAIN_DMA
[ Upstream commit 4a8d8a14c0 ]

The arm64 DMA-mapping implementation sets the DMA ops to the IOMMU DMA
ops if we detect that an IOMMU is present for the master and the DMA
ranges are valid.

In the case when the IOMMU domain for the device is not of type
IOMMU_DOMAIN_DMA, then we have no business swizzling the ops, since
we're not in control of the underlying address space. This patch leaves
the DMA ops alone for masters attached to non-DMA IOMMU domains.

Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-15 15:53:13 +01:00
Julien Thierry
e059fc3c36 arm/arm64: kvm: Disable branch profiling in HYP code
commit f9b269f309 upstream.

When HYP code runs into branch profiling code, it attempts to jump to
unmapped memory, causing a HYP Panic.

Disable the branch profiling for code designed to run at HYP mode.

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 10:08:32 +01:00
Dongjiu Geng
d7d5a30e23 arm/arm64: KVM: set right LR register value for 32 bit guest when inject abort
commit fd6c8c206f upstream.

When a exception is trapped to EL2, hardware uses  ELR_ELx to hold
the current fault instruction address. If KVM wants to inject a
abort to 32 bit guest, it needs to set the LR register for the
guest to emulate this abort happened in the guest. Because ARM32
architecture is pipelined execution, so the LR value has an offset to
the fault instruction address.

The offsets applied to Link value for exceptions as shown below,
which should be added for the ARM32 link register(LR).

Table taken from ARMv8 ARM DDI0487B-B, table G1-10:
Exception			Offset, for PE state of:
				A32 	  T32
Undefined Instruction 		+4 	  +2
Prefetch Abort 			+4 	  +4
Data Abort 			+8 	  +8
IRQ or FIQ 			+4 	  +4

  [ Removed unused variables in inject_abt to avoid compile warnings.
    -- Christoffer ]

Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Tested-by: Haibin Zhang <zhanghaibin7@huawei.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 10:08:32 +01:00
Mark Rutland
011b44af00 arm64: ensure __dump_instr() checks addr_limit
commit 7a7003b1da upstream.

It's possible for a user to deliberately trigger __dump_instr with a
chosen kernel address.

Let's avoid problems resulting from this by using get_user() rather than
__get_user(), ensuring that we don't erroneously access kernel memory.

Where we use __dump_instr() on kernel text, we already switch to
KERNEL_DS, so this shouldn't adversely affect those cases.

Fixes: 60ffc30d56 ("arm64: Exception handling")
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-08 10:08:32 +01:00
Will Deacon
d49527ed48 arm64: fault: Route pte translation faults via do_translation_fault
commit 760bfb47c3 upstream.

We currently route pte translation faults via do_page_fault, which elides
the address check against TASK_SIZE before invoking the mm fault handling
code. However, this can cause issues with the path walking code in
conjunction with our word-at-a-time implementation because
load_unaligned_zeropad can end up faulting in kernel space if it reads
across a page boundary and runs into a page fault (e.g. by attempting to
read from a guard region).

In the case of such a fault, load_unaligned_zeropad has registered a
fixup to shift the valid data and pad with zeroes, however the abort is
reported as a level 3 translation fault and we dispatch it straight to
do_page_fault, despite it being a kernel address. This results in calling
a sleeping function from atomic context:

  BUG: sleeping function called from invalid context at arch/arm64/mm/fault.c:313
  in_atomic(): 0, irqs_disabled(): 0, pid: 10290
  Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
  [...]
  [<ffffff8e016cd0cc>] ___might_sleep+0x134/0x144
  [<ffffff8e016cd158>] __might_sleep+0x7c/0x8c
  [<ffffff8e016977f0>] do_page_fault+0x140/0x330
  [<ffffff8e01681328>] do_mem_abort+0x54/0xb0
  Exception stack(0xfffffffb20247a70 to 0xfffffffb20247ba0)
  [...]
  [<ffffff8e016844fc>] el1_da+0x18/0x78
  [<ffffff8e017f399c>] path_parentat+0x44/0x88
  [<ffffff8e017f4c9c>] filename_parentat+0x5c/0xd8
  [<ffffff8e017f5044>] filename_create+0x4c/0x128
  [<ffffff8e017f59e4>] SyS_mkdirat+0x50/0xc8
  [<ffffff8e01684e30>] el0_svc_naked+0x24/0x28
  Code: 36380080 d5384100 f9400800 9402566d (d4210000)
  ---[ end trace 2d01889f2bca9b9f ]---

Fix this by dispatching all translation faults to do_translation_faults,
which avoids invoking the page fault logic for faults on kernel addresses.

Reported-by: Ankit Jain <ankijain@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:44:02 +02:00
Marc Zyngier
7dbd64284b arm64: Make sure SPsel is always set
commit 5371513fb3 upstream.

When the kernel is entered at EL2 on an ARMv8.0 system, we construct
the EL1 pstate and make sure this uses the the EL1 stack pointer
(we perform an exception return to EL1h).

But if the kernel is either entered at EL1 or stays at EL2 (because
we're on a VHE-capable system), we fail to set SPsel, and use whatever
stack selection the higher exception level has choosen for us.

Let's not take any chance, and make sure that SPsel is set to one
before we decide the mode we're going to run in.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-05 09:44:02 +02:00
Marc Zyngier
b40aa8b047 ARM64: dts: marvell: armada-37xx: Fix GIC maintenance interrupt
commit 95696d292e upstream.

The GIC-500 integrated in the Armada-37xx SoCs is compliant with
the GICv3 architecture, and thus provides a maintenance interrupt
that is required for hypervisors to function correctly.

With the interrupt provided in the DT, KVM now works as it should.
Tested on an Espressobin system.

Fixes: adbc3695d9 ("arm64: dts: add the Marvell Armada 3700 family and a development board")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-13 14:13:36 -07:00
Dave Martin
27e7506c33 arm64: fpsimd: Prevent registers leaking across exec
commit 096622104e upstream.

There are some tricky dependencies between the different stages of
flushing the FPSIMD register state during exec, and these can race
with context switch in ways that can cause the old task's regs to
leak across.  In particular, a context switch during the memset() can
cause some of the task's old FPSIMD registers to reappear.

Disabling preemption for this small window would be no big deal for
performance: preemption is already disabled for similar scenarios
like updating the FPSIMD registers in sigreturn.

So, instead of rearranging things in ways that might swap existing
subtle bugs for new ones, this patch just disables preemption
around the FPSIMD state flushing so that races of this type can't
occur here.  This brings fpsimd_flush_thread() into line with other
code paths.

Fixes: 674c242c93 ("arm64: flush FP/SIMD state correctly after execve()")
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-02 07:07:54 +02:00
Mark Rutland
509d8b52bb arm64: mm: abort uaccess retries upon fatal signal
commit 289d07a2dc upstream.

When there's a fatal signal pending, arm64's do_page_fault()
implementation returns 0. The intent is that we'll return to the
faulting userspace instruction, delivering the signal on the way.

However, if we take a fatal signal during fixing up a uaccess, this
results in a return to the faulting kernel instruction, which will be
instantly retried, resulting in the same fault being taken forever. As
the task never reaches userspace, the signal is not delivered, and the
task is left unkillable. While the task is stuck in this state, it can
inhibit the forward progress of the system.

To avoid this, we must ensure that when a fatal signal is pending, we
apply any necessary fixup for a faulting kernel instruction. Thus we
will return to an error path, and it is up to that code to make forward
progress towards delivering the fatal signal.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Laura Abbott <labbott@redhat.com>
Reviewed-by: Steve Capper <steve.capper@arm.com>
Tested-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-09-02 07:07:53 +02:00
Kees Cook
1f2347a095 mm: revert x86_64 and arm64 ELF_ET_DYN_BASE base changes
commit c715b72c1b upstream.

Moving the x86_64 and arm64 PIE base from 0x555555554000 to 0x000100000000
broke AddressSanitizer.  This is a partial revert of:

  eab09532d4 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE")
  02445990a9 ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB")

The AddressSanitizer tool has hard-coded expectations about where
executable mappings are loaded.

The motivation for changing the PIE base in the above commits was to
avoid the Stack-Clash CVEs that allowed executable mappings to get too
close to heap and stack.  This was mainly a problem on 32-bit, but the
64-bit bases were moved too, in an effort to proactively protect those
systems (proofs of concept do exist that show 64-bit collisions, but
other recent changes to fix stack accounting and setuid behaviors will
minimize the impact).

The new 32-bit PIE base is fine for ASan (since it matches the ET_EXEC
base), so only the 64-bit PIE base needs to be reverted to let x86 and
arm64 ASan binaries run again.  Future changes to the 64-bit PIE base on
these architectures can be made optional once a more dynamic method for
dealing with AddressSanitizer is found.  (e.g.  always loading PIE into
the mmap region for marked binaries.)

Link: http://lkml.kernel.org/r/20170807201542.GA21271@beast
Fixes: eab09532d4 ("binfmt_elf: use ELF_ET_DYN_BASE only for PIE")
Fixes: 02445990a9 ("arm64: move ELF_ET_DYN_BASE to 4GB / 4MB")
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Kostya Serebryany <kcc@google.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-24 17:12:20 -07:00
Mark Rutland
e95ec3582a arm64: mm: fix show_pte KERN_CONT fallout
[ Upstream commit 6ef4fb387d ]

Recent changes made KERN_CONT mandatory for continued lines. In the
absence of KERN_CONT, a newline may be implicit inserted by the core
printk code.

In show_pte, we (erroneously) use printk without KERN_CONT for continued
prints, resulting in output being split across a number of lines, and
not matching the intended output, e.g.

[ff000000000000] *pgd=00000009f511b003
, *pud=00000009f4a80003
, *pmd=0000000000000000

Fix this by using pr_cont() for all the continuations.

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-06 18:59:48 -07:00
Moritz Fischer
3209f3f69e ARM64: zynqmp: Fix i2c node's compatible string
[ Upstream commit c415f9e830 ]

The Zynq Ultrascale MP uses version 1.4 of the Cadence IP core
which fixes some silicon bugs that needed software workarounds
in Version 1.0 that was used on Zynq systems.

Signed-off-by: Moritz Fischer <mdf@kernel.org>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
Cc: Rob Herring <robh+dt@kernel.org>
Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-06 18:59:47 -07:00
Michal Simek
e3603533ae ARM64: zynqmp: Fix W=1 dtc 1.4 warnings
[ Upstream commit 4ea2a6be95 ]

The patch removes these warnings reported by dtc 1.4:
Warning (unit_address_vs_reg): Node /amba_apu has a reg or ranges
property, but no unit name
Warning (unit_address_vs_reg): Node /memory has a reg or ranges
property, but no unit name

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-06 18:59:46 -07:00
Marc Zyngier
445a945ad6 ARM64: dts: marvell: armada37xx: Fix timer interrupt specifiers
commit 88cda00733 upstream.

Contrary to popular belief, PPIs connected to a GICv3 to not have
an affinity field similar to that of GICv2. That is consistent
with the fact that GICv3 is designed to accomodate thousands of
CPUs, and fitting them as a bitmap in a byte is... difficult.

Fixes: adbc3695d9 ("arm64: dts: add the Marvell Armada 3700 family and a development board")
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:42:22 +02:00
Kees Cook
70779e0ebb arm64: move ELF_ET_DYN_BASE to 4GB / 4MB
commit 02445990a9 upstream.

Now that explicitly executed loaders are loaded in the mmap region, we
have more freedom to decide where we position PIE binaries in the
address space to avoid possible collisions with mmap or stack regions.

For 64-bit, align to 4GB to allow runtimes to use the entire 32-bit
address space for 32-bit pointers.  On 32-bit use 4MB, to match ARM.
This could be 0x8000, the standard ET_EXEC load address, but that is
needlessly close to the NULL address, and anyone running arm compat PIE
will have an MMU, so the tight mapping is not needed.

Link: http://lkml.kernel.org/r/1498251600-132458-4-git-send-email-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-21 07:42:21 +02:00
Mark Salter
982d8d92f2 arm64: fix NULL dereference in have_cpu_die()
commit 335d2c2d19 upstream.

Commit 5c492c3f52 ("arm64: smp: Add function to determine if cpus are
stuck in the kernel") added a helper function to determine if die() is
supported in cpu_ops. This function assumes a cpu will have a valid
cpu_ops entry, but that may not be the case for cpu0 is spin-table or
parking protocol is used to boot secondary cpus. In that case, there
is a NULL dereference if have_cpu_die() is called by cpu0. So add a
check for a valid cpu_ops before dereferencing it.

Fixes: 5c492c3f52 ("arm64: smp: Add function to determine if cpus are stuck in the kernel")
Signed-off-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05 14:40:31 +02:00
Lorenzo Pieralisi
7661b19687 ARM64/ACPI: Fix BAD_MADT_GICC_ENTRY() macro implementation
commit cb7cf772d8 upstream.

The BAD_MADT_GICC_ENTRY() macro checks if a GICC MADT entry passes
muster from an ACPI specification standpoint. Current macro detects the
MADT GICC entry length through ACPI firmware version (it changed from 76
to 80 bytes in the transition from ACPI 5.1 to ACPI 6.0 specification)
but always uses (erroneously) the ACPICA (latest) struct (ie struct
acpi_madt_generic_interrupt - that is 80-bytes long) length to check if
the current GICC entry memory record exceeds the MADT table end in
memory as defined by the MADT table header itself, which may result in
false negatives depending on the ACPI firmware version and how the MADT
entries are laid out in memory (ie on ACPI 5.1 firmware MADT GICC
entries are 76 bytes long, so by adding 80 to a GICC entry start address
in memory the resulting address may well be past the actual MADT end,
triggering a false negative).

Fix the BAD_MADT_GICC_ENTRY() macro by reshuffling the condition checks
and update them to always use the firmware version specific MADT GICC
entry length in order to carry out boundary checks.

Fixes: b6cfb27737 ("ACPI / ARM64: add BAD_MADT_GICC_ENTRY() macro")
Reported-by: Julien Grall <julien.grall@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Julien Grall <julien.grall@arm.com>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Cc: Al Stone <ahs3@redhat.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05 14:40:29 +02:00
Ard Biesheuvel
f88f06e183 arm64: assembler: make adr_l work in modules under KASLR
[ Upstream commit 41c066f2c4 ]

When CONFIG_RANDOMIZE_MODULE_REGION_FULL=y, the offset between loaded
modules and the core kernel may exceed 4 GB, putting symbols exported
by the core kernel out of the reach of the ordinary adrp/add instruction
pairs used to generate relative symbol references. So make the adr_l
macro emit a movz/movk sequence instead when executing in module context.

While at it, remove the pointless special case for the stack pointer.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05 14:40:25 +02:00
Jerome Brunet
13fa36f9fb ARM64: dts: meson-gxbb-odroidc2: fix GbE tx link breakage
[ Upstream commit feb3cbea09 ]

OdroidC2 GbE link breaks under heavy tx transfer. This happens even if the
MAC does not enable Energy Efficient Ethernet (No Low Power state Idle on
the Tx path). The problem seems to come from the phy Rx path, entering the
LPI state.

Disabling EEE advertisement on the phy prevent this feature to be
negociated with the link partner and solve the issue.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-05 14:40:20 +02:00
Will Deacon
99f66b5182 arm64/vdso: Fix nsec handling for CLOCK_MONOTONIC_RAW
commit dbb236c1ce upstream.

Recently vDSO support for CLOCK_MONOTONIC_RAW was added in
49eea433b3 ("arm64: Add support for CLOCK_MONOTONIC_RAW in
clock_gettime() vDSO"). Noticing that the core timekeeping code
never set tkr_raw.xtime_nsec, the vDSO implementation didn't
bother exposing it via the data page and instead took the
unshifted tk->raw_time.tv_nsec value which was then immediately
shifted left in the vDSO code.

Unfortunately, by accellerating the MONOTONIC_RAW clockid, it
uncovered potential 1ns time inconsistencies caused by the
timekeeping core not handing sub-ns resolution.

Now that the core code has been fixed and is actually setting
tkr_raw.xtime_nsec, we need to take that into account in the
vDSO by adding it to the shifted raw_time value, in order to
fix the user-visible inconsistency. Rather than do that at each
use (and expand the data page in the process), instead perform
the shift/addition operation when populating the data page and
remove the shift from the vDSO code entirely.

[jstultz: minor whitespace tweak, tried to improve commit
 message to make it more clear this fixes a regression]
Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Daniel Mentz <danielmentz@google.com>
Acked-by: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Stephen Boyd <stephen.boyd@linaro.org>
Cc: Miroslav Lichvar <mlichvar@redhat.com>
Link: http://lkml.kernel.org/r/1496965462-20003-4-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-29 13:00:30 +02:00
Kristina Martsenko
9e09d90ac5 arm64: entry: improve data abort handling of tagged pointers
commit 276e93279a upstream.

This backport has a minor difference from the upstream commit: it adds
the asm-uaccess.h file, which is not present in 4.9, because 4.9 does
not have commit b4b8664d29 ("arm64: don't pull uaccess.h into *.S").

Original patch description:

When handling a data abort from EL0, we currently zero the top byte of
the faulting address, as we assume the address is a TTBR0 address, which
may contain a non-zero address tag. However, the address may be a TTBR1
address, in which case we should not zero the top byte. This patch fixes
that. The effect is that the full TTBR1 address is passed to the task's
signal handler (or printed out in the kernel log).

When handling a data abort from EL1, we leave the faulting address
intact, as we assume it's either a TTBR1 address or a TTBR0 address with
tag 0x00. This is true as far as I'm aware, we don't seem to access a
tagged TTBR0 address anywhere in the kernel. Regardless, it's easy to
forget about address tags, and code added in the future may not always
remember to remove tags from addresses before accessing them. So add tag
handling to the EL1 data abort handler as well. This also makes it
consistent with the EL0 data abort handler.

Fixes: d50240a5f6 ("arm64: mm: permit use of tagged pointers at EL0")
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14 15:06:05 +02:00
Kristina Martsenko
1d61ccb5ac arm64: hw_breakpoint: fix watchpoint matching for tagged pointers
commit 7dcd9dd8ce upstream.

This backport has a small difference from the upstream commit:
 - The address tag is removed in watchpoint_handler() instead of
   get_distance_from_watchpoint(), because 4.9 does not have commit
   fdfeff0f9e ("arm64: hw_breakpoint: Handle inexact watchpoint
   addresses").

Original patch description:

When we take a watchpoint exception, the address that triggered the
watchpoint is found in FAR_EL1. We compare it to the address of each
configured watchpoint to see which one was hit.

The configured watchpoint addresses are untagged, while the address in
FAR_EL1 will have an address tag if the data access was done using a
tagged address. The tag needs to be removed to compare the address to
the watchpoints.

Currently we don't remove it, and as a result can report the wrong
watchpoint as being hit (specifically, always either the highest TTBR0
watchpoint or lowest TTBR1 watchpoint). This patch removes the tag.

Fixes: d50240a5f6 ("arm64: mm: permit use of tagged pointers at EL0")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14 15:06:05 +02:00
Kristina Martsenko
791d94ef40 arm64: traps: fix userspace cache maintenance emulation on a tagged pointer
commit 81cddd65b5 upstream.

This backport has a minor difference from the upstream commit, as v4.9
did not yet have the refactoring done by commit 8b6e70fccf ("arm64:
traps: correctly handle MRS/MSR with XZR").

Original patch description:

When we emulate userspace cache maintenance in the kernel, we can
currently send the task a SIGSEGV even though the maintenance was done
on a valid address. This happens if the address has a non-zero address
tag, and happens to not be mapped in.

When we get the address from a user register, we don't currently remove
the address tag before performing cache maintenance on it. If the
maintenance faults, we end up in either __do_page_fault, where find_vma
can't find the VMA if the address has a tag, or in do_translation_fault,
where the tagged address will appear to be above TASK_SIZE. In both
cases, the address is not mapped in, and the task is sent a SIGSEGV.

This patch removes the tag from the address before using it. With this
patch, the fault is handled correctly, the address gets mapped in, and
the cache maintenance succeeds.

As a second bug, if cache maintenance (correctly) fails on an invalid
tagged address, the address gets passed into arm64_notify_segfault,
where find_vma fails to find the VMA due to the tag, and the wrong
si_code may be sent as part of the siginfo_t of the segfault. With this
patch, the correct si_code is sent.

Fixes: 7dd01aef05 ("arm64: trap userspace "dc cvau" cache operation on errata-affected core")
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14 15:06:04 +02:00
Marc Zyngier
8abce1e49c arm64: KVM: Allow unaligned accesses at EL2
commit 78fd6dcf11 upstream.

We currently have the SCTLR_EL2.A bit set, trapping unaligned accesses
at EL2, but we're not really prepared to deal with it. So far, this
has been unnoticed, until GCC 7 started emitting those (in particular
64bit writes on a 32bit boundary).

Since the rest of the kernel is pretty happy about that, let's follow
its example and set SCTLR_EL2.A to zero. Modern CPUs don't really
care.

Reported-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14 15:05:56 +02:00
Marc Zyngier
b9824dd75f arm64: KVM: Preserve RES1 bits in SCTLR_EL2
commit d68c1f7fd1 upstream.

__do_hyp_init has the rather bad habit of ignoring RES1 bits and
writing them back as zero. On a v8.0-8.2 CPU, this doesn't do anything
bad, but may end-up being pretty nasty on future revisions of the
architecture.

Let's preserve those bits so that we don't have to fix this later on.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-14 15:05:56 +02:00
Daniel Borkmann
21e3113298 bpf, arm64: fix faulty emission of map access in tail calls
[ Upstream commit d8b54110ee ]

Shubham was recently asking on netdev why in arm64 JIT we don't multiply
the index for accessing the tail call map by 8. That led me into testing
out arm64 JIT wrt tail calls and it turned out I got a NULL pointer
dereference on the tail call.

The buggy access is at:

  prog = array->ptrs[index];
  if (prog == NULL)
      goto out;

  [...]
  00000060:  d2800e0a  mov x10, #0x70 // #112
  00000064:  f86a682a  ldr x10, [x1,x10]
  00000068:  f862694b  ldr x11, [x10,x2]
  0000006c:  b40000ab  cbz x11, 0x00000080
  [...]

The code triggering the crash is f862694b. x1 at the time contains the
address of the bpf array, x10 offsetof(struct bpf_array, ptrs). Meaning,
above we load the pointer to the program at map slot 0 into x10. x10
can then be NULL if the slot is not occupied, which we later on try to
access with a user given offset in x2 that is the map index.

Fix this by emitting the following instead:

  [...]
  00000060:  d2800e0a  mov x10, #0x70 // #112
  00000064:  8b0a002a  add x10, x1, x10
  00000068:  d37df04b  lsl x11, x2, #3
  0000006c:  f86b694b  ldr x11, [x10,x11]
  00000070:  b40000ab  cbz x11, 0x00000084
  [...]

This basically adds the offset to ptrs to the base address of the bpf
array we got and we later on access the map with an index * 8 offset
relative to that. The tail call map itself is basically one large area
with meta data at the head followed by the array of prog pointers.
This makes tail calls working again, tested on Cavium ThunderX ARMv8.

Fixes: ddb55992b0 ("arm64: bpf: implement bpf_tail_call() helper")
Reported-by: Shubham Bansal <illusionist.neo@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-06-07 12:07:43 +02:00
Mark Rutland
e817a7fb2f arm64: uaccess: ensure extension of access_ok() addr
commit a06040d7a7 upstream.

Our access_ok() simply hands its arguments over to __range_ok(), which
implicitly assummes that the addr parameter is 64 bits wide. This isn't
necessarily true for compat code, which might pass down a 32-bit address
parameter.

In these cases, we don't have a guarantee that the address has been zero
extended to 64 bits, and the upper bits of the register may contain
unknown values, potentially resulting in a suprious failure.

Avoid this by explicitly casting the addr parameter to an unsigned long
(as is done on other architectures), ensuring that the parameter is
widened appropriately.

Fixes: 0aea86a217 ("arm64: User access library functions")
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:44:45 +02:00
Mark Rutland
4775fbcc92 arm64: armv8_deprecated: ensure extension of addr
commit 55de49f9aa upstream.

Our compat swp emulation holds the compat user address in an unsigned
int, which it passes to __user_swpX_asm(). When a 32-bit value is passed
in a register, the upper 32 bits of the register are unknown, and we
must extend the value to 64 bits before we can use it as a base address.

This patch casts the address to unsigned long to ensure it has been
suitably extended, avoiding the potential issue, and silencing a related
warning from clang.

Fixes: bd35a4adc4 ("arm64: Port SWP/SWPB emulation support from arm")
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:44:45 +02:00
Mark Rutland
f2e4f4e538 arm64: ensure extension of smp_store_release value
commit 994870bead upstream.

When an inline assembly operand's type is narrower than the register it
is allocated to, the least significant bits of the register (up to the
operand type's width) are valid, and any other bits are permitted to
contain any arbitrary value. This aligns with the AAPCS64 parameter
passing rules.

Our __smp_store_release() implementation does not account for this, and
implicitly assumes that operands have been zero-extended to the width of
the type being stored to. Thus, we may store unknown values to memory
when the value type is narrower than the pointer type (e.g. when storing
a char to a long).

This patch fixes the issue by casting the value operand to the same
width as the pointer operand in all cases, which ensures that the value
is zero-extended as we expect. We use the same union trickery as
__smp_load_acquire and {READ,WRITE}_ONCE() to avoid GCC complaining that
pointers are potentially cast to narrower width integers in unreachable
paths.

A whitespace issue at the top of __smp_store_release() is also
corrected.

No changes are necessary for __smp_load_acquire(). Load instructions
implicitly clear any upper bits of the register, and the compiler will
only consider the least significant bits of the register as valid
regardless.

Fixes: 47933ad41a ("arch: Introduce smp_load_acquire(), smp_store_release()")
Fixes: 878a84d5a8 ("arm64: add missing data types in smp_load_acquire/smp_store_release")
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:44:45 +02:00
Mark Rutland
88675139a8 arm64: xchg: hazard against entire exchange variable
commit fee960bed5 upstream.

The inline assembly in __XCHG_CASE() uses a +Q constraint to hazard
against other accesses to the memory location being exchanged. However,
the pointer passed to the constraint is a u8 pointer, and thus the
hazard only applies to the first byte of the location.

GCC can take advantage of this, assuming that other portions of the
location are unchanged, as demonstrated with the following test case:

union u {
	unsigned long l;
	unsigned int i[2];
};

unsigned long update_char_hazard(union u *u)
{
	unsigned int a, b;

	a = u->i[1];
	asm ("str %1, %0" : "+Q" (*(char *)&u->l) : "r" (0UL));
	b = u->i[1];

	return a ^ b;
}

unsigned long update_long_hazard(union u *u)
{
	unsigned int a, b;

	a = u->i[1];
	asm ("str %1, %0" : "+Q" (*(long *)&u->l) : "r" (0UL));
	b = u->i[1];

	return a ^ b;
}

The linaro 15.08 GCC 5.1.1 toolchain compiles the above as follows when
using -O2 or above:

0000000000000000 <update_char_hazard>:
   0:	d2800001 	mov	x1, #0x0                   	// #0
   4:	f9000001 	str	x1, [x0]
   8:	d2800000 	mov	x0, #0x0                   	// #0
   c:	d65f03c0 	ret

0000000000000010 <update_long_hazard>:
  10:	b9400401 	ldr	w1, [x0,#4]
  14:	d2800002 	mov	x2, #0x0                   	// #0
  18:	f9000002 	str	x2, [x0]
  1c:	b9400400 	ldr	w0, [x0,#4]
  20:	4a000020 	eor	w0, w1, w0
  24:	d65f03c0 	ret

This patch fixes the issue by passing an unsigned long pointer into the
+Q constraint, as we do for our cmpxchg code. This may hazard against
more than is necessary, but this is better than missing a necessary
hazard.

Fixes: 305d454aaa ("arm64: atomics: implement native {relaxed, acquire, release} atomics")
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:44:44 +02:00
Daniel Lezcano
31a331c8cf arm64: dts: hi6220: Reset the mmc hosts
commit 0fbdf9953b upstream.

The MMC hosts could be left in an unconsistent or uninitialized state from
the firmware. Instead of assuming, the firmware did the right things, let's
reset the host controllers.

This change fixes a bug when the mmc2/sdio is initialized leading to a hung
task:

[  242.704294] INFO: task kworker/7:1:675 blocked for more than 120 seconds.
[  242.711129]       Not tainted 4.9.0-rc8-00017-gcf0251f #3
[  242.716571] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  242.724435] kworker/7:1     D    0   675      2 0x00000000
[  242.729973] Workqueue: events_freezable mmc_rescan
[  242.734796] Call trace:
[  242.737269] [<ffff00000808611c>] __switch_to+0xa8/0xb4
[  242.742437] [<ffff000008d07c04>] __schedule+0x1c0/0x67c
[  242.747689] [<ffff000008d08254>] schedule+0x40/0xa0
[  242.752594] [<ffff000008d0b284>] schedule_timeout+0x1c4/0x35c
[  242.758366] [<ffff000008d08e38>] wait_for_common+0xd0/0x15c
[  242.763964] [<ffff000008d09008>] wait_for_completion+0x28/0x34
[  242.769825] [<ffff000008a1a9f4>] mmc_wait_for_req_done+0x40/0x124
[  242.775949] [<ffff000008a1ab98>] mmc_wait_for_req+0xc0/0xf8
[  242.781549] [<ffff000008a1ac3c>] mmc_wait_for_cmd+0x6c/0x84
[  242.787149] [<ffff000008a26610>] mmc_io_rw_direct_host+0x9c/0x114
[  242.793270] [<ffff000008a26aa0>] sdio_reset+0x34/0x7c
[  242.798347] [<ffff000008a1d46c>] mmc_rescan+0x2fc/0x360

[ ... ]

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:44:44 +02:00
Marc Zyngier
d0fb4b7d00 arm64: KVM: Do not use stack-protector to compile EL2 code
commit cde13b5dad upstream.

We like living dangerously. Nothing explicitely forbids stack-protector
to be used in the EL2 code, while distributions routinely compile their
kernel with it. We're just lucky that no code actually triggers the
instrumentation.

Let's not try our luck for much longer, and disable stack-protector
for code living at EL2.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-25 15:44:43 +02:00
Marc Zyngier
884ba252f3 arm64: KVM: Fix decoding of Rt/Rt2 when trapping AArch32 CP accesses
commit c667186f1c upstream.

Our 32bit CP14/15 handling inherited some of the ARMv7 code for handling
the trapped system registers, completely missing the fact that the
fields for Rt and Rt2 are now 5 bit wide, and not 4...

Let's fix it, and provide an accessor for the most common Rt case.

Reviewed-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-20 14:28:36 +02:00
Daniel Borkmann
493d0a7be3 bpf, arm64: fix jit branch offset related to ldimm64
[ Upstream commit ddc665a4bb ]

When the instruction right before the branch destination is
a 64 bit load immediate, we currently calculate the wrong
jump offset in the ctx->offset[] array as we only account
one instruction slot for the 64 bit load immediate although
it uses two BPF instructions. Fix it up by setting the offset
into the right slot after we incremented the index.

Before (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // #3
  00000028:  d2800041  mov x1, #0x2 // #2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  54ffff82  b.cs 0x00000020
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl #16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl #32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl #48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl #16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl #32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl #48
  [...]

After (ldimm64 test 1):

  [...]
  00000020:  52800007  mov w7, #0x0 // #0
  00000024:  d2800060  mov x0, #0x3 // #3
  00000028:  d2800041  mov x1, #0x2 // #2
  0000002c:  eb01001f  cmp x0, x1
  00000030:  540000a2  b.cs 0x00000044
  00000034:  d29fffe7  mov x7, #0xffff // #65535
  00000038:  f2bfffe7  movk x7, #0xffff, lsl #16
  0000003c:  f2dfffe7  movk x7, #0xffff, lsl #32
  00000040:  f2ffffe7  movk x7, #0xffff, lsl #48
  00000044:  d29dddc7  mov x7, #0xeeee // #61166
  00000048:  f2bdddc7  movk x7, #0xeeee, lsl #16
  0000004c:  f2ddddc7  movk x7, #0xeeee, lsl #32
  00000050:  f2fdddc7  movk x7, #0xeeee, lsl #48
  [...]

Also, add a couple of test cases to make sure JITs pass
this test. Tested on Cavium ThunderX ARMv8. The added
test cases all pass after the fix.

Fixes: 8eee539dde ("arm64: bpf: fix out-of-bounds read in bpf2a64_offset()")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Xi Wang <xi.wang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-14 14:00:21 +02:00
Catalin Marinas
f46fdb8a26 arm64: Improve detection of user/non-user mappings in set_pte(_at)
commit ec663d967b upstream.

Commit cab15ce604 ("arm64: Introduce execute-only page access
permissions") allowed a valid user PTE to have the PTE_USER bit clear.
As a consequence, the pte_valid_not_user() macro in set_pte() was
replaced with pte_valid_global() under the assumption that only user
pages have the nG bit set. EFI mappings, however, also have the nG bit
set and set_pte() wrongly ignores issuing the DSB+ISB.

This patch reinstates the pte_valid_not_user() macro and adds the
PTE_UXN bit check since all kernel mappings have this bit set. For
clarity, pte_exec() is renamed to pte_user_exec() as it only checks for
the absence of PTE_UXN. Consequently, the user executable check in
set_pte_at() drops the pte_ng() test since pte_user_exec() is
sufficient.

Fixes: cab15ce604 ("arm64: Introduce execute-only page access permissions")
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-14 14:00:15 +02:00
Geert Uytterhoeven
e33fb57428 arm64: dts: r8a7795: Mark EthernetAVB device node disabled
commit 0d1390ff28 upstream.

Device nodes representing I/O devices should be marked disabled in the
SoC-specific DTS, and overridden by board-specific DTSes where needed.

Fixes: a92843c8a6 ("arm64: dts: r8a7795: add EthernetAVB device node")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-05-14 14:00:15 +02:00
Andy Gross
bec9918bb4 firmware: qcom: scm: Fix interrupted SCM calls
[ Upstream commit 82bcd08702 ]

This patch adds a Qualcomm specific quirk to the arm_smccc_smc call.

On Qualcomm ARM64 platforms, the SMC call can return before it has
completed.  If this occurs, the call can be restarted, but it requires
using the returned session ID value from the interrupted SMC call.

The quirk stores off the session ID from the interrupted call in the
quirk structure so that it can be used by the caller.

This patch folds in a fix given by Sricharan R:
https://lkml.org/lkml/2016/9/28/272

Signed-off-by: Andy Gross <andy.gross@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:21 +02:00
Andy Gross
007f0a2f2c arm: kernel: Add SMC structure parameter
[ Upstream commit 680a0873e1 ]

This patch adds a quirk parameter to the arm_smccc_(smc/hvc) calls.
The quirk structure allows for specialized SMC operations due to SoC
specific requirements.  The current arm_smccc_(smc/hvc) is renamed and
macros are used instead to specify the standard arm_smccc_(smc/hvc) or
the arm_smccc_(smc/hvc)_quirk function.

This patch and partial implementation was suggested by Will Deacon.

Signed-off-by: Andy Gross <andy.gross@linaro.org>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:21 +02:00
Bjorn Helgaas
5582c1980e arm64: PCI: Add local struct device pointers
[ Upstream commit dfd1972c2b ]

Use a local "struct device *dev" for brevity.  No functional change
intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:17 +02:00
Tomasz Nowicki
cc49b39f3f arm64: PCI: Manage controller-specific data on per-controller basis
[ Upstream commit 093d24a204 ]

Currently we use one shared global acpi_pci_root_ops structure to keep
controller-specific ops. We pass its pointer to acpi_pci_root_create() and
associate it with a host bridge instance for good.  Such a design implies
serious drawback. Any potential manipulation on the single system-wide
acpi_pci_root_ops leads to kernel crash. The structure content is not
really changing even across multiple host bridges creation; thus it was not
an issue so far.

In preparation for adding ECAM quirks mechanism (where controller-specific
PCI ops may be different for each host bridge) allocate new
acpi_pci_root_ops and fill in with data for each bridge. Now it is safe to
have different controller-specific info. As a consequence free
acpi_pci_root_ops when host bridge is released.

No functional changes in this patch.

Signed-off-by: Tomasz Nowicki <tn@semihalf.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:17 +02:00
John Garry
dcc4c67581 arm64: dts: hisi: fix hip06 sas am-max-trans quirk
[ Upstream commit f65e786604 ]

The string for the am max transmissions quirk property
is not correct -> fix it.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Wei Xu <xuwei5@hisilicon.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:16 +02:00
Victor Kamensky
3715dbf77f arm64: mm: unaligned access by user-land should be received as SIGBUS
commit 09a6adf53d upstream.

After 52d7523 (arm64: mm: allow the kernel to handle alignment faults on
user accesses) commit user-land accesses that produce unaligned exceptions
like in case of aarch32 ldm/stm/ldrd/strd instructions operating on
unaligned memory received by user-land as SIGSEGV. It is wrong, it should
be reported as SIGBUS as it was before 52d7523 commit.

Changed do_bad_area function to take signal and code parameters out of esr
value using fault_info table, so in case of do_alignment_fault fault
user-land will receive SIGBUS. Wrapped access to fault_info table into
esr_to_fault_info function.

Fixes: 52d7523 (arm64: mm: allow the kernel to handle alignment faults on user accesses)
Signed-off-by: Victor Kamensky <kamensky@cisco.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-12 12:41:11 +02:00
Neeraj Upadhyay
b9ed800f71 arm64: kaslr: Fix up the kernel image alignment
commit afd0e5a876 upstream.

If kernel image extends across alignment boundary, existing
code increases the KASLR offset by size of kernel image. The
offset is masked after resizing. There are cases, where after
masking, we may still have kernel image extending across
boundary. This eventually results in only 2MB block getting
mapped while creating the page tables. This results in data aborts
while accessing unmapped regions during second relocation (with
kaslr offset) in __primary_switch. To fix this problem, round up the
kernel image size, by swapper block size, before adding it for
correction.

For example consider below case, where kernel image still crosses
1GB alignment boundary, after masking the offset, which is fixed
by rounding up kernel image size.

SWAPPER_TABLE_SHIFT = 30
Swapper using section maps with section size 2MB.
CONFIG_PGTABLE_LEVELS = 3
VA_BITS = 39

_text  : 0xffffff8008080000
_end   : 0xffffff800aa1b000
offset : 0x1f35600000
mask = ((1UL << (VA_BITS - 2)) - 1) & ~(SZ_2M - 1)

(_text + offset) >> SWAPPER_TABLE_SHIFT = 0x3fffffe7c
(_end + offset) >> SWAPPER_TABLE_SHIFT  = 0x3fffffe7d

offset after existing correction (before mask) = 0x1f37f9b000
(_text + offset) >> SWAPPER_TABLE_SHIFT = 0x3fffffe7d
(_end + offset) >> SWAPPER_TABLE_SHIFT  = 0x3fffffe7d

offset (after mask) = 0x1f37e00000
(_text + offset) >> SWAPPER_TABLE_SHIFT = 0x3fffffe7c
(_end + offset) >> SWAPPER_TABLE_SHIFT  = 0x3fffffe7d

new offset w/ rounding up = 0x1f38000000
(_text + offset) >> SWAPPER_TABLE_SHIFT = 0x3fffffe7d
(_end + offset) >> SWAPPER_TABLE_SHIFT  = 0x3fffffe7d

Fixes: f80fb3a3d5 ("arm64: add support for kernel ASLR")
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-30 09:41:26 +02:00