linux-stable.git/include/linux, branch v4.9.95

arm/arm64: smccc: Implement SMCCC v1.1 inline primitive

2018-04-20T06:21:06+00:00

From: Marc Zyngier 

commit f2d3b2e8759a5833df6f022e42df2d581e6d843c upstream.

One of the major improvement of SMCCC v1.1 is that it only clobbers
the first 4 registers, both on 32 and 64bit. This means that it
becomes very easy to provide an inline version of the SMC call
primitive, and avoid performing a function call to stash the
registers that would otherwise be clobbered by SMCCC v1.0.

Reviewed-by: Robin Murphy 
Tested-by: Ard Biesheuvel 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

arm/arm64: smccc: Make function identifiers an unsigned quantity

2018-04-20T06:21:06+00:00

From: Marc Zyngier 

commit ded4c39e93f3b72968fdb79baba27f3b83dad34c upstream.

Function identifiers are a 32bit, unsigned quantity. But we never
tell so to the compiler, resulting in the following:

 4ac:   b26187e0        mov     x0, #0xffffffff80000001

We thus rely on the firmware narrowing it for us, which is not
always a reasonable expectation.

Cc: stable@vger.kernel.org
Reported-by: Ard Biesheuvel 
Acked-by: Ard Biesheuvel 
Reviewed-by: Robin Murphy 
Tested-by: Ard Biesheuvel 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

firmware/psci: Expose SMCCC version through psci_ops

2018-04-20T06:21:05+00:00

From: Marc Zyngier 

commit e78eef554a912ef6c1e0bbf97619dafbeae3339f upstream.

Since PSCI 1.0 allows the SMCCC version to be (indirectly) probed,
let's do that at boot time, and expose the version of the calling
convention as part of the psci_ops structure.

Acked-by: Lorenzo Pieralisi 
Reviewed-by: Robin Murphy 
Tested-by: Ard Biesheuvel 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

firmware/psci: Expose PSCI conduit

2018-04-20T06:21:05+00:00

From: Marc Zyngier 

commit 09a8d6d48499f93e2abde691f5800081cd858726 upstream.

In order to call into the firmware to apply workarounds, it is
useful to find out whether we're using HVC or SMC. Let's expose
this through the psci_ops.

Acked-by: Lorenzo Pieralisi 
Reviewed-by: Robin Murphy 
Tested-by: Ard Biesheuvel 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

arm64: KVM: Report SMCCC_ARCH_WORKAROUND_1 BP hardening support

2018-04-20T06:21:05+00:00

From: Marc Zyngier 

commit 6167ec5c9145cdf493722dfd80a5d48bafc4a18a upstream.

A new feature of SMCCC 1.1 is that it offers firmware-based CPU
workarounds. In particular, SMCCC_ARCH_WORKAROUND_1 provides
BP hardening for CVE-2017-5715.

If the host has some mitigation for this issue, report that
we deal with it using SMCCC_ARCH_WORKAROUND_1, as we apply the
host workaround on every guest exit.

Tested-by: Ard Biesheuvel 
Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
[v4.9: account for files moved to virt/ upstream]
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

arm/arm64: KVM: Advertise SMCCC v1.1

2018-04-20T06:21:05+00:00

From: Marc Zyngier 

commit 09e6be12effdb33bf7210c8867bbd213b66a499e upstream.

The new SMC Calling Convention (v1.1) allows for a reduced overhead
when calling into the firmware, and provides a new feature discovery
mechanism.

Make it visible to KVM guests.

Tested-by: Ard Biesheuvel 
Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier 
Signed-off-by: Catalin Marinas 
[v4.9: account for files moved to virt/ upstream]
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

mm: Introduce lm_alias

2018-04-20T06:20:44+00:00

From: Laura Abbott 

commit 568c5fe5a54f2654f5a4c599c45b8a62ed9a2013 upstream.

Certain architectures may have the kernel image mapped separately to
alias the linear map. Introduce a macro lm_alias to translate a kernel
image symbol into its linear alias. This is used in part with work to
add CONFIG_DEBUG_VIRTUAL support for arm64.

Reviewed-by: Mark Rutland 
Tested-by: Mark Rutland 
Signed-off-by: Laura Abbott 
Signed-off-by: Will Deacon 
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

drivers/firmware: Expose psci_get_version through psci_ops structure

2018-04-20T06:20:43+00:00

From: Will Deacon 

commit d68e3ba5303f7e1099f51fdcd155f5263da8569b upstream.

Entry into recent versions of ARM Trusted Firmware will invalidate the CPU
branch predictor state in order to protect against aliasing attacks.

This patch exposes the PSCI "VERSION" function via psci_ops, so that it
can be invoked outside of the PSCI driver where necessary.

Acked-by: Lorenzo Pieralisi 
Signed-off-by: Will Deacon 
Signed-off-by: Catalin Marinas 
Signed-off-by: Mark Rutland  [v4.9 backport]
Tested-by: Greg Hackmann 
Signed-off-by: Greg Kroah-Hartman

sched/deadline: Use the revised wakeup rule for suspending constrained dl tasks

2018-04-13T17:48:23+00:00

[ Upstream commit 3effcb4247e74a51f5d8b775a1ee4abf87cc089a ]

We have been facing some problems with self-suspending constrained
deadline tasks. The main reason is that the original CBS was not
designed for such sort of tasks.

One problem reported by Xunlei Pang takes place when a task
suspends, and then is awakened before the deadline, but so close
to the deadline that its remaining runtime can cause the task
to have an absolute density higher than allowed. In such situation,
the original CBS assumes that the task is facing an early activation,
and so it replenishes the task and set another deadline, one deadline
in the future. This rule works fine for implicit deadline tasks.
Moreover, it allows the system to adapt the period of a task in which
the external event source suffered from a clock drift.

However, this opens the window for bandwidth leakage for constrained
deadline tasks. For instance, a task with the following parameters:

  runtime   = 5 ms
  deadline  = 7 ms
  [density] = 5 / 7 = 0.71
  period    = 1000 ms

If the task runs for 1 ms, and then suspends for another 1ms,
it will be awakened with the following parameters:

  remaining runtime = 4
  laxity = 5

presenting a absolute density of 4 / 5 = 0.80.

In this case, the original CBS would assume the task had an early
wakeup. Then, CBS will reset the runtime, and the absolute deadline will
be postponed by one relative deadline, allowing the task to run.

The problem is that, if the task runs this pattern forever, it will keep
receiving bandwidth, being able to run 1ms every 2ms. Following this
behavior, the task would be able to run 500 ms in 1 sec. Thus running
more than the 5 ms / 1 sec the admission control allowed it to run.

Trying to address the self-suspending case, Luca Abeni, Giuseppe
Lipari, and Juri Lelli [1] revisited the CBS in order to deal with
self-suspending tasks. In the new approach, rather than
replenishing/postponing the absolute deadline, the revised wakeup rule
adjusts the remaining runtime, reducing it to fit into the allowed
density.

A revised version of the idea is:

At a given time t, the maximum absolute density of a task cannot be
higher than its relative density, that is:

  runtime / (deadline - t) <= dl_runtime / dl_deadline

Knowing the laxity of a task (deadline - t), it is possible to move
it to the other side of the equality, thus enabling to define max
remaining runtime a task can use within the absolute deadline, without
over-running the allowed density:

  runtime = (dl_runtime / dl_deadline) * (deadline - t)

For instance, in our previous example, the task could still run:

  runtime = ( 5 / 7 ) * 5
  runtime = 3.57 ms

Without causing damage for other deadline tasks. It is note worthy
that the laxity cannot be negative because that would cause a negative
runtime. Thus, this patch depends on the patch:

  df8eac8cafce ("sched/deadline: Throttle a constrained deadline task activated after the deadline")

Which throttles a constrained deadline task activated after the
deadline.

Finally, it is also possible to use the revised wakeup rule for
all other tasks, but that would require some more discussions
about pros and cons.

Reported-by: Xunlei Pang 
Signed-off-by: Daniel Bristot de Oliveira 
[peterz: replaced dl_is_constrained with dl_is_implicit]
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Juri Lelli 
Cc: Linus Torvalds 
Cc: Luca Abeni 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Romulo Silva de Oliveira 
Cc: Steven Rostedt 
Cc: Thomas Gleixner 
Cc: Tommaso Cucinotta 
Link: http://lkml.kernel.org/r/5c800ab3a74a168a84ee5f3f84d12a02e11383be.1495803804.git.bristot@redhat.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

net/mlx4: Fix the check in attaching steering rules

2018-04-13T17:48:19+00:00

[ Upstream commit 6dc06c08bef1c746ff8da33dab677cfbacdcad32 ]

Our previous patch (cited below) introduced a regression
for RAW Eth QPs.

Fix it by checking if the QP number provided by user-space
exists, hence allowing steering rules to be added for valid
QPs only.

Fixes: 89c557687a32 ("net/mlx4_en: Avoid adding steering rules with invalid ring")
Reported-by: Or Gerlitz 
Signed-off-by: Talat Batheesh 
Signed-off-by: Tariq Toukan 
Acked-by: Or Gerlitz 
Reviewed-by: Leon Romanovsky 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman