linux-stable.git/arch, branch v5.1.4

s390/mm: convert to the generic get_user_pages_fast code

2019-05-22T05:39:58+00:00

commit 1a42010cdc26bb7e5912984f3c91b8c6d55f089a upstream.

Define the gup_fast_permitted to check against the asce_limit of the
mm attached to the current task, then replace the s390 specific gup
code with the generic implementation in mm/gup.c.

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

s390/mm: make the pxd_offset functions more robust

2019-05-22T05:39:58+00:00

commit d1874a0c2805fcfa9162c972d6b7541e57adb542 upstream.

Change the way how pgd_offset, p4d_offset, pud_offset and pmd_offset
walk the page tables. pgd_offset now always calculates the index for
the top-level page table and adds it to the pgd, this is either a
segment table offset for a 2-level setup, a region-3 offset for 3-levels,
region-2 offset for 4-levels, or a region-1 offset for a 5-level setup.
The other three functions p4d_offset, pud_offset and pmd_offset will
only add the respective offset if they dereference the passed pointer.

With the new way of walking the page tables a sequence like this from
mm/gup.c now works:

     pgdp = pgd_offset(current->mm, addr);
     pgd = READ_ONCE(*pgdp);
     p4dp = p4d_offset(&pgd, addr);
     p4d = READ_ONCE(*p4dp);
     pudp = pud_offset(&p4d, addr);
     pud = READ_ONCE(*pudp);
     pmdp = pmd_offset(&pud, addr);
     pmd = READ_ONCE(*pmdp);

Signed-off-by: Martin Schwidefsky 
Signed-off-by: Greg Kroah-Hartman

powerpc/32s: fix flush_hash_pages() on SMP

2019-05-22T05:39:58+00:00

commit 397d2300b08cdee052053e362018cdb6dd65eea2 upstream.

flush_hash_pages() runs with data translation off, so current
task_struct has to be accesssed using physical address.

Fixes: f7354ccac844 ("powerpc/32: Remove CURRENT_THREAD_INFO and rename TI_CPU")
Cc: stable@vger.kernel.org # v5.1+
Reported-by: Erhard F. 
Signed-off-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Signed-off-by: Greg Kroah-Hartman

xen/pvh: correctly setup the PV EFI interface for dom0

2019-05-22T05:39:57+00:00

commit 72813bfbf0276a97c82af038efb5f02dcdd9e310 upstream.

This involves initializing the boot params EFI related fields and the
efi global variable.

Without this fix a PVH dom0 doesn't detect when booted from EFI, and
thus doesn't support accessing any of the EFI related data.

Reported-by: PGNet Dev 
Signed-off-by: Roger Pau Monné 
Reviewed-by: Boris Ostrovsky 
Signed-off-by: Boris Ostrovsky 
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Greg Kroah-Hartman

xen/pvh: set xen_domain_type to HVM in xen_pvh_init

2019-05-22T05:39:57+00:00

commit c9f804d64bb93c8dbf957df1d7e9de11380e522d upstream.

Or else xen_domain() returns false despite xen_pvh being set.

Signed-off-by: Roger Pau Monné 
Reviewed-by: Boris Ostrovsky 
Signed-off-by: Boris Ostrovsky 
Cc: stable@vger.kernel.org # 4.19+
Signed-off-by: Greg Kroah-Hartman

KVM: lapic: Busy wait for timer to expire when using hv_timer

2019-05-22T05:39:57+00:00

commit ee66e453db13d4837a0dcf9d43efa7a88603161b upstream.

...now that VMX's preemption timer, i.e. the hv_timer, also adjusts its
programmed time based on lapic_timer_advance_ns.  Without the delay, a
guest can see a timer interrupt arrive before the requested time when
KVM is using the hv_timer to emulate the guest's interrupt.

Fixes: c5ce8235cffa0 ("KVM: VMX: Optimize tscdeadline timer latency")
Cc: 
Cc: Wanpeng Li 
Reviewed-by: Liran Alon 
Signed-off-by: Sean Christopherson 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: Skip EFER vs. guest CPUID checks for host-initiated writes

2019-05-22T05:39:57+00:00

commit 11988499e62b310f3bf6f6d0a807a06d3f9ccc96 upstream.

KVM allows userspace to violate consistency checks related to the
guest's CPUID model to some degree.  Generally speaking, userspace has
carte blanche when it comes to guest state so long as jamming invalid
state won't negatively affect the host.

Currently this is seems to be a non-issue as most of the interesting
EFER checks are missing, e.g. NX and LME, but those will be added
shortly.  Proactively exempt userspace from the CPUID checks so as not
to break userspace.

Note, the efer_reserved_bits check still applies to userspace writes as
that mask reflects the host's capabilities, e.g. KVM shouldn't allow a
guest to run with NX=1 if it has been disabled in the host.

Fixes: d80174745ba39 ("KVM: SVM: Only allow setting of EFER_SVME when CPUID SVM is set")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

Revert "KVM: nVMX: Expose RDPMC-exiting only when guest supports PMU"

2019-05-22T05:39:56+00:00

commit f93f7ede087f2edcc18e4b02310df5749a6b5a61 upstream.

The RDPMC-exiting control is dependent on the existence of the RDPMC
instruction itself, i.e. is not tied to the "Architectural Performance
Monitoring" feature.  For all intents and purposes, the control exists
on all CPUs with VMX support since RDPMC also exists on all VCPUs with
VMX supported.  Per Intel's SDM:

  The RDPMC instruction was introduced into the IA-32 Architecture in
  the Pentium Pro processor and the Pentium processor with MMX technology.
  The earlier Pentium processors have performance-monitoring counters, but
  they must be read with the RDMSR instruction.

Because RDPMC-exiting always exists, KVM requires the control and refuses
to load if it's not available.  As a result, hiding the PMU from a guest
breaks nested virtualization if the guest attemts to use KVM.

While it's not explicitly stated in the RDPMC pseudocode, the VM-Exit
check for RDPMC-exiting follows standard fault vs. VM-Exit prioritization
for privileged instructions, e.g. occurs after the CPL/CR0.PE/CR4.PCE
checks, but before the counter referenced in ECX is checked for validity.

In other words, the original KVM behavior of injecting a #GP was correct,
and the KVM unit test needs to be adjusted accordingly, e.g. eat the #GP
when the unit test guest (L3 in this case) executes RDPMC without
RDPMC-exiting set in the unit test host (L2).

This reverts commit e51bfdb68725dc052d16241ace40ea3140f938aa.

Fixes: e51bfdb68725 ("KVM: nVMX: Expose RDPMC-exiting only when guest supports PMU")
Reported-by: David Hill 
Cc: Saar Amar 
Cc: Mihai Carabas 
Cc: Jim Mattson 
Cc: Liran Alon 
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

ARM: dts: imx: Fix the AR803X phy-mode

2019-05-22T05:39:55+00:00

commit 0672d22a19244cdb0e5c753125c1a55a120db5d0 upstream.

Commit 6d4cd041f0af ("net: phy: at803x: disable delay only for RGMII mode")
exposed an issue on imx DTS files using AR8031/AR8035 PHYs.

The end result is that the boards can no longer obtain an IP address
via UDHCP, for example.

Quoting Andrew Lunn:

"The problem here is, all the DTs were broken since day 0. However,
because the PHY driver was also broken, nobody noticed and it
worked. Now that the PHY driver has been fixed, all the bugs in the
DTs now become an issue"

To fix this problem, the phy-mode property needs to be "rgmii-id",  which
has the following meaning as per
Documentation/devicetree/bindings/net/ethernet.txt:

"RGMII with internal RX and TX delays provided by the PHY, the MAC should
not add the RX or TX delays in this case)"

Tested on imx6-sabresd, imx6sx-sdb and imx7d-pico boards with
successfully restored networking.

Based on the initial submission from Steve Twiss for the
imx6qdl-sabresd.

Signed-off-by: Fabio Estevam 
Tested-by: Baruch Siach 
Tested-by: Soeren Moch 
Tested-by: Steve Twiss 
Tested-by: Adam Thomson 
Signed-off-by: Steve Twiss 
Tested-by: Marc Kleine-Budde 
Signed-off-by: Marc Kleine-Budde 
Signed-off-by: Shawn Guo 
Cc: "George G. Davis" 
Signed-off-by: Greg Kroah-Hartman

bpf, arm64: remove prefetch insn in xadd mapping

2019-05-22T05:39:49+00:00

commit 8968c67a82ab7501bc3b9439c3624a49b42fe54c upstream.

Prefetch-with-intent-to-write is currently part of the XADD mapping in
the AArch64 JIT and follows the kernel's implementation of atomic_add.
This may interfere with other threads executing the LDXR/STXR loop,
leading to potential starvation and fairness issues. Drop the optional
prefetch instruction.

Fixes: 85f68fe89832 ("bpf, arm64: implement jiting of BPF_XADD")
Reported-by: Will Deacon 
Signed-off-by: Daniel Borkmann 
Acked-by: Jean-Philippe Brucker 
Acked-by: Will Deacon 
Signed-off-by: Alexei Starovoitov 
Signed-off-by: Greg Kroah-Hartman