When booting through OF, setup_disp_bat() does nothing because
disp_BAT are not set. By change, it used to work because BOOTX
buffer is mapped 1:1 at address 0x81000000 by the bootloader, and
btext_setup_display() sets virt addr same as phys addr.

But since commit 215b8237 ("powerpc/32s: set up an early static
hash table for KASAN."), a temporary page table overrides the
bootloader mapping.

This 0x81000000 is also problematic with the newly implemented
Kernel Userspace Access Protection (KUAP) because it is within user
address space.

This patch fixes those issues by properly setting disp_BAT through
a call to btext_prepare_BAT(), allowing setup_disp_bat() to
properly setup BAT3 for early bootx screen buffer access.
Reported-by: Mathieu Malaterre <malat@debian.org>
Fixes: 215b8237 ("powerpc/32s: set up an early static hash table for KASAN.")
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

The change to pmdp_invalidate() to mark the pmd with _PAGE_INVALID
broke the synchronisation against lock free lookups,
__find_linux_pte()'s pmd_none() check no longer returns true for such
cases.

Fix this by adding a check for this condition as well.

Fixes: da7ad366 ("powerpc/mm/book3s: Update pmd_present to look at _PAGE_PRESENT bit")
Cc: stable@vger.kernel.org # v4.20+
Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit 1b2443a5 ("powerpc/book3s64: Avoid multiple endian
conversion in pte helpers") changed the actual bitwise tests in
pte_access_permitted by using pte_write() and pte_present() helpers
rather than raw bitwise testing _PAGE_WRITE and _PAGE_PRESENT bits.

The pte_present() change now returns true for PTEs which are
!_PAGE_PRESENT and _PAGE_INVALID, which is the combination used by
pmdp_invalidate() to synchronize access from lock-free lookups.
pte_access_permitted() is used by pmd_access_permitted(), so allowing
GUP lock free access to proceed with such PTEs breaks this
synchronisation.

This bug has been observed on a host using the hash page table MMU,
with random crashes and corruption in guests, usually together with
bad PMD messages in the host.

Fix this by adding an explicit check in pmd_access_permitted(), and
documenting the condition explicitly.

The pte_write() change should be okay, and would prevent GUP from
falling back to the slow path when encountering savedwrite PTEs, which
matches what x86 (that does not implement savedwrite) does.

Fixes: 1b2443a5 ("powerpc/book3s64: Avoid multiple endian conversion in pte helpers")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

In the old days, _PAGE_EXEC didn't exist on 6xx aka book3s/32.
Therefore, allthough __mapin_ram_chunk() was already mapping kernel
text with PAGE_KERNEL_TEXT and the rest with PAGE_KERNEL, the entire
memory was executable. Part of the memory (first 512kbytes) was
mapped with BATs instead of page table, but it was also entirely
mapped as executable.

In commit 385e89d5 ("powerpc/mm: add exec protection on
powerpc 603"), we started adding exec protection to some 6xx, namely
the 603, for pages mapped via pagetables.

Then, in commit 63b2bc61 ("powerpc/mm/32s: Use BATs for
STRICT_KERNEL_RWX"), the exec protection was extended to BAT mapped
memory, so that really only the kernel text could be executed.

The problem here is that kexec is based on copying some code into
upper part of memory then executing it from there in order to install
a fresh new kernel at its definitive location.

However, the code is position independant and first part of it is
just there to deactivate the MMU and jump to the second part. So it
is possible to run this first part inplace instead of running the
copy. Once the MMU is off, there is no protection anymore and the
second part of the code will just run as before.
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Fixes: 63b2bc61 ("powerpc/mm/32s: Use BATs for STRICT_KERNEL_RWX")
Cc: stable@vger.kernel.org # v5.1+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Pull tracing warning fix from Steven Rostedt:
 "Make the GCC 9 warning for sub struct memset go away.

  GCC 9 now warns about calling memset() on partial structures when it
  goes across multiple fields. This adds a helper for the place in
  tracing that does this type of clearing of a structure"

* tag 'trace-v5.2-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Silence GCC 9 array bounds warning

Pull KVM fixes from Paolo Bonzini:
 "The usual smattering of fixes and tunings that came in too late for
  the merge window, but should not wait four months before they appear
  in a release.

  I also travelled a bit more than usual in the first part of May, which
  didn't help with picking up patches and reports promptly"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (33 commits)
  KVM: x86: fix return value for reserved EFER
  tools/kvm_stat: fix fields filter for child events
  KVM: selftests: Wrap vcpu_nested_state_get/set functions with x86 guard
  kvm: selftests: aarch64: compile with warnings on
  kvm: selftests: aarch64: fix default vm mode
  kvm: selftests: aarch64: dirty_log_test: fix unaligned memslot size
  KVM: s390: fix memory slot handling for KVM_SET_USER_MEMORY_REGION
  KVM: x86/pmu: do not mask the value that is written to fixed PMUs
  KVM: x86/pmu: mask the result of rdpmc according to the width of the counters
  x86/kvm/pmu: Set AMD's virt PMU version to 1
  KVM: x86: do not spam dmesg with VMCS/VMCB dumps
  kvm: Check irqchip mode before assign irqfd
  kvm: svm/avic: fix off-by-one in checking host APIC ID
  KVM: selftests: do not blindly clobber registers in guest asm
  KVM: selftests: Remove duplicated TEST_ASSERT in hyperv_cpuid.c
  KVM: LAPIC: Expose per-vCPU timer_advance_ns to userspace
  KVM: LAPIC: Fix lapic_timer_advance_ns parameter overflow
  kvm: vmx: Fix -Wmissing-prototypes warnings
  KVM: nVMX: Fix using __this_cpu_read() in preemptible context
  kvm: fix compilation on s390
  ...

Pull /dev/random fix from Ted Ts'o:
 "Fix a soft lockup regression when reading from /dev/random in early
  boot"

* tag 'random_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
  random: fix soft lockup when trying to read from an uninitialized blocking pool

Fixes: eb9d1bf0: "random: only read from /dev/random after its pool has received 128 bits"
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Starting with GCC 9, -Warray-bounds detects cases when memset is called
starting on a member of a struct but the size to be cleared ends up
writing over further members.

Such a call happens in the trace code to clear, at once, all members
after and including `seq` on struct trace_iterator:

    In function 'memset',
        inlined from 'ftrace_dump' at kernel/trace/trace.c:8914:3:
    ./include/linux/string.h:344:9: warning: '__builtin_memset' offset
    [8505, 8560] from the object at 'iter' is out of the bounds of
    referenced subobject 'seq' with type 'struct trace_seq' at offset
    4368 [-Warray-bounds]
      344 |  return __builtin_memset(p, c, size);
          |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

In order to avoid GCC complaining about it, we compute the address
ourselves by adding the offsetof distance instead of referring
directly to the member.

Since there are two places doing this clear (trace.c and trace_kdb.c),
take the chance to move the workaround into a single place in
the internal header.

Link: http://lkml.kernel.org/r/20190523124535.GA12931@gmail.comSigned-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
[ Removed unnecessary parenthesis around "iter" ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

Pull ext4 fixes from Ted Ts'o:
 "Bug fixes (including a regression fix) for ext4"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix dcache lookup of !casefolded directories
  ext4: do not delete unlinked inode from orphan list on failed truncate
  ext4: wait for outstanding dio during truncate in nojournal mode
  ext4: don't perform block validity checks on the journal inode

Pull libnvdimm fixes from Dan Williams:

 - Fix a regression that disabled device-mapper dax support

 - Remove unnecessary hardened-user-copy overhead (>30%) for dax
   read(2)/write(2).

 - Fix some compilation warnings.

* tag 'libnvdimm-fixes-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
  libnvdimm/pmem: Bypass CONFIG_HARDENED_USERCOPY overhead
  dax: Arrange for dax_supported check to span multiple devices
  libnvdimm: Fix compilation warnings with W=1

Pull tracing fixes from Steven Rostedt:
 "Tom Zanussi sent me some small fixes and cleanups to the histogram
  code and I forgot to incorporate them.

  I also added a small clean up patch that was sent to me a while ago
  and I just noticed it"

* tag 'trace-v5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  kernel/trace/trace.h: Remove duplicate header of trace_seq.h
  tracing: Add a check_val() check before updating cond_snapshot() track_val
  tracing: Check keys for variable references in expressions too
  tracing: Prevent hist_field_var_ref() from accessing NULL tracing_map_elts

Found by visual inspection, this wasn't caught by my xfstest, since it's
effect is ignoring positive dentries in the cache the fallback just goes
to the disk.  it was introduced in the last iteration of the
case-insensitive patch.

d_compare should return 0 when the entries match, so make sure we are
correctly comparing the entire string if the encoding feature is set and
we are on a case-INsensitive directory.

Fixes: b886ee3e ("ext4: Support case-insensitive file name lookups")
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Pull SCSI fixes from James Bottomley:
 "This is the same set of patches sent in the merge window as the final
  pull except that Martin's read only rework is replaced with a simple
  revert of the original change that caused the regression.

  Everything else is an obvious fix or small cleanup"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  Revert "scsi: sd: Keep disk read-only when re-reading partition"
  scsi: bnx2fc: fix incorrect cast to u64 on shift operation
  scsi: smartpqi: Reporting unhandled SCSI errors
  scsi: myrs: Fix uninitialized variable
  scsi: lpfc: Update lpfc version to 12.2.0.2
  scsi: lpfc: add check for loss of ndlp when sending RRQ
  scsi: lpfc: correct rcu unlock issue in lpfc_nvme_info_show
  scsi: lpfc: resolve lockdep warnings
  scsi: qedi: remove set but not used variables 'cdev' and 'udev'
  scsi: qedi: remove memset/memcpy to nfunc and use func instead
  scsi: qla2xxx: Add cleanup for PCI EEH recovery

Pull block fixes from Jens Axboe:

 - NVMe pull request from Keith, with fixes from a few folks.

 - bio and sbitmap before atomic barrier fixes (Andrea)

 - Hang fix for blk-mq freeze and unfreeze (Bob)

 - Single segment count regression fix (Christoph)

 - AoE now has a new maintainer

 - tools/io_uring/ Makefile fix, and sync with liburing (me)

* tag 'for-linus-20190524' of git://git.kernel.dk/linux-block: (23 commits)
  tools/io_uring: sync with liburing
  tools/io_uring: fix Makefile for pthread library link
  blk-mq: fix hang caused by freeze/unfreeze sequence
  block: remove the bi_seg_{front,back}_size fields in struct bio
  block: remove the segment size check in bio_will_gap
  block: force an unlimited segment size on queues with a virt boundary
  block: don't decrement nr_phys_segments for physically contigous segments
  sbitmap: fix improper use of smp_mb__before_atomic()
  bio: fix improper use of smp_mb__before_atomic()
  aoe: list new maintainer for aoe driver
  nvme-pci: use blk-mq mapping for unmanaged irqs
  nvme: update MAINTAINERS
  nvme: copy MTFA field from identify controller
  nvme: fix memory leak for power latency tolerance
  nvme: release namespace SRCU protection before performing controller ioctls
  nvme: merge nvme_ns_ioctl into nvme_ioctl
  nvme: remove the ifdef around nvme_nvm_ioctl
  nvme: fix srcu locking on error return in nvme_get_ns_from_disk
  nvme: Fix known effects
  nvme-pci: Sync queues on reset
  ...

Merge tag 'linux-kselftest-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull Kselftest fixes from Shuah Khan:

 - Two fixes to regressions introduced in kselftest Makefile test run
   output refactoring work (Kees Cook)

 - Adding Atom support to syscall_arg_fault test (Tong Bo)

* tag 'linux-kselftest-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests/timers: Add missing fflush(stdout) calls
  selftests: Remove forced unbuffering for test running
  selftests/x86: Support Atom for syscall_arg_fault test

Pull Devicetree fixes from Rob Herring:

 - Update checkpatch.pl to use DT vendor-prefixes.yaml

 - Fix DT binding references to files converted to DT schema

 - Clean-up Arm CPU binding examples to match schema

 - Add Sifive block versioning scheme documentation

 - Pass binding directory base to validation tools for reference lookups

* tag 'devicetree-fixes-for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  checkpatch.pl: Update DT vendor prefix check
  dt: bindings: mtd: replace references to nand.txt with nand-controller.yaml
  dt-bindings: interrupt-controller: arm,gic: Fix schema errors in example
  dt-bindings: arm: Clean up CPU binding examples
  dt: fix refs that were renamed to json with the same file name
  dt-bindings: Pass binding directory to validation tools
  dt-bindings: sifive: describe sifive-blocks versioning

Pule more SPDX updates from Greg KH:
 "Here is another set of reviewed patches that adds SPDX tags to
  different kernel files, based on a set of rules that are being used to
  parse the comments to try to determine that the license of the file is
  "GPL-2.0-or-later".

  Only the "obvious" versions of these matches are included here, a
  number of "non-obvious" variants of text have been found but those
  have been postponed for later review and analysis.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers"

* tag 'spdx-5.2-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (85 commits)
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 125
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 123
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 122
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 121
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 120
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 119
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 118
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 116
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 114
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 113
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 112
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 111
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 110
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 106
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 105
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 104
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 103
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 102
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 101
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 98
  ...

The kernel test robot has reported that the use of __this_cpu_add()
causes bug messages like:

  BUG: using __this_cpu_add() in preemptible [00000000] code: ...

Given the imprecise nature of the count and the possibility of resetting
the count and doing the measurement again, this is not really a big
problem to use the unprotected __this_cpu_*() functions.

To make the preemption checking code happy, the this_cpu_*() functions
will be used if CONFIG_DEBUG_PREEMPT is defined.

The imprecise nature of the locking counts are also documented with
the suggestion that we should run the measurement a few times with the
counts reset in between to get a better picture of what is going on
under the hood.

Fixes: a8654596 ("locking/rwsem: Enable lock event counting")
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 11988499 ("KVM: x86: Skip EFER vs. guest CPUID checks for
host-initiated writes", 2019-04-02) introduced a "return false" in a
function returning int, and anyway set_efer has a "nonzero on error"
conventon so it should be returning 1.
Reported-by: Pavel Machek <pavel@denx.de>
Fixes: 11988499 ("KVM: x86: Skip EFER vs. guest CPUID checks for host-initiated writes")
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The fields filter would not work with child fields, as the respective
parents would not be included. No parents displayed == no childs displayed.
To reproduce, run on s390 (would work on other platforms, too, but would
require a different filter name):
- Run 'kvm_stat -d'
- Press 'f'
- Enter 'instruct'
Notice that events like instruction_diag_44 or instruction_diag_500 are not
displayed - the output remains empty.
With this patch, we will filter by matching events and their parents.
However, consider the following example where we filter by
instruction_diag_44:

  kvm statistics - summary
                   regex filter: instruction_diag_44
   Event                                         Total %Total CurAvg/s
   exit_instruction                                276  100.0       12
     instruction_diag_44                           256   92.8       11
   Total                                           276              12

Note that the parent ('exit_instruction') displays the total events, but
the childs listed do not match its total (256 instead of 276). This is
intended (since we're filtering all but one child), but might be confusing
on first sight.
Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

struct kvm_nested_state is only available on x86 so far. To be able
to compile the code on other architectures as well, we need to wrap
the related code with #ifdefs.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

aarch64 fixups needed to compile with warnings as errors.
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

VM_MODE_P52V48_4K is not a valid mode for AArch64. Replace its
use in vm_create_default() with a mode that works and represents
a good AArch64 default. (We didn't ever see a problem with this
because we don't have any unit tests using vm_create_default(),
but it's good to get it fixed in advance.)
Reported-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The memory slot size must be aligned to the host's page size. When
testing a guest with a 4k page size on a host with a 64k page size,
then 3 guest pages are not host page size aligned. Since we just need
a nearly arbitrary number of extra pages to ensure the memslot is not
aligned to a 64 host-page boundary for this test, then we can use
16, as that's 64k aligned, but not 64 * 64k aligned.

Fixes: 76d58e0f ("KVM: fix KVM_CLEAR_DIRTY_LOG for memory slots of unaligned size", 2019-04-17)
Signed-off-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

kselftests exposed a problem in the s390 handling for memory slots.
Right now we only do proper memory slot handling for creation of new
memory slots. Neither MOVE, nor DELETION are handled properly. Let us
implement those.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

According to the SDM, for MSR_IA32_PERFCTR0/1 "the lower-order 32 bits of
each MSR may be written with any value, and the high-order 8 bits are
sign-extended according to the value of bit 31", but the fixed counters
in real hardware are limited to the width of the fixed counters ("bits
beyond the width of the fixed-function counter are reserved and must be
written as zeros").  Fix KVM to do the same.
Reported-by: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

This patch will simplify the changes in the next, by enforcing the
masking of the counters to RDPMC and RDMSR.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

After commit:

  672ff6cf ("KVM: x86: Raise #GP when guest vCPU do not support PMU")

my AMD guests started #GPing like this:

  general protection fault: 0000 [#1] PREEMPT SMP
  CPU: 1 PID: 4355 Comm: bash Not tainted 5.1.0-rc6+ #3
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
  RIP: 0010:x86_perf_event_update+0x3b/0xa0

with Code: pointing to RDPMC. It is RDPMC because the guest has the
hardware watchdog CONFIG_HARDLOCKUP_DETECTOR_PERF enabled which uses
perf. Instrumenting kvm_pmu_rdpmc() some, showed that it fails due to:

  if (!pmu->version)
  	return 1;

which the above commit added. Since AMD's PMU leaves the version at 0,
that causes the #GP injection into the guest.

Set pmu->version arbitrarily to 1 and move it above the non-applicable
struct kvm_pmu members.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: kvm@vger.kernel.org
Cc: Liran Alon <liran.alon@oracle.com>
Cc: Mihai Carabas <mihai.carabas@oracle.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: stable@vger.kernel.org
Fixes: 672ff6cf ("KVM: x86: Raise #GP when guest vCPU do not support PMU")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Userspace can easily set up invalid processor state in such a way that
dmesg will be filled with VMCS or VMCB dumps.  Disable this by default
using a module parameter.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

When assigning kvm irqfd we didn't check the irqchip mode but we allow
KVM_IRQFD to succeed with all the irqchip modes.  However it does not
make much sense to create irqfd even without the kernel chips.  Let's
provide a arch-dependent helper to check whether a specific irqfd is
allowed by the arch.  At least for x86, it should make sense to check:

- when irqchip mode is NONE, all irqfds should be disallowed, and,

- when irqchip mode is SPLIT, irqfds that are with resamplefd should
  be disallowed.

For either of the case, previously we'll silently ignore the irq or
the irq ack event if the irqchip mode is incorrect.  However that can
cause misterious guest behaviors and it can be hard to triage.  Let's
fail KVM_IRQFD even earlier to detect these incorrect configurations.

CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Radim Krčmář <rkrcmar@redhat.com>
CC: Alex Williamson <alex.williamson@redhat.com>
CC: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Current logic does not allow VCPU to be loaded onto CPU with
APIC ID 255. This should be allowed since the host physical APIC ID
field in the AVIC Physical APIC table entry is an 8-bit value,
and APIC ID 255 is valid in system with x2APIC enabled.
Instead, do not allow VCPU load if the host APIC ID cannot be
represented by an 8-bit value.

Also, use the more appropriate AVIC_PHYSICAL_ID_ENTRY_HOST_PHYSICAL_ID_MASK
instead of AVIC_MAX_PHYSICAL_ID_COUNT.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The guest_code of sync_regs_test is assuming that the compiler will not
touch %r11 outside the asm that increments it, which is a bit brittle.
Instead, we can increment a variable and use a dummy asm to ensure the
increment is not optimized away.  However, we also need to use a
callee-save register or the compiler will insert a save/restore around
the vmexit, breaking the whole idea behind the test.

(Yes, "if it ain't broken...", but I would like the test to be clean
before it is copied into the upcoming s390 selftests).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The check for entry->index == 0 is done twice. One time should
be sufficient.
Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Expose per-vCPU timer_advance_ns to userspace, so it is able to
query the auto-adjusted value.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Liran Alon <liran.alon@oracle.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

After commit c3941d9e (KVM: lapic: Allow user to disable adaptive tuning of
timer advancement), '-1' enables adaptive tuning starting from default
advancment of 1000ns. However, we should expose an int instead of an overflow
uint module parameter.

Before patch:

/sys/module/kvm/parameters/lapic_timer_advance_ns:4294967295

After patch:

/sys/module/kvm/parameters/lapic_timer_advance_ns:-1

Fixes: c3941d9e (KVM: lapic: Allow user to disable adaptive tuning of timer advancement)
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Liran Alon <liran.alon@oracle.com>
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

We get a warning when build kernel W=1:
arch/x86/kvm/vmx/vmx.c:6365:6: warning: no previous prototype for ‘vmx_update_host_rsp’ [-Wmissing-prototypes]
 void vmx_update_host_rsp(struct vcpu_vmx *vmx, unsigned long host_rsp)

Add the missing declaration to fix this.
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

 BUG: using __this_cpu_read() in preemptible [00000000] code: qemu-system-x86/4590
  caller is nested_vmx_enter_non_root_mode+0xebd/0x1790 [kvm_intel]
  CPU: 4 PID: 4590 Comm: qemu-system-x86 Tainted: G           OE     5.1.0-rc4+ #1
  Call Trace:
   dump_stack+0x67/0x95
   __this_cpu_preempt_check+0xd2/0xe0
   nested_vmx_enter_non_root_mode+0xebd/0x1790 [kvm_intel]
   nested_vmx_run+0xda/0x2b0 [kvm_intel]
   handle_vmlaunch+0x13/0x20 [kvm_intel]
   vmx_handle_exit+0xbd/0x660 [kvm_intel]
   kvm_arch_vcpu_ioctl_run+0xa2c/0x1e50 [kvm]
   kvm_vcpu_ioctl+0x3ad/0x6d0 [kvm]
   do_vfs_ioctl+0xa5/0x6e0
   ksys_ioctl+0x6d/0x80
   __x64_sys_ioctl+0x1a/0x20
   do_syscall_64+0x6f/0x6c0
   entry_SYSCALL_64_after_hwframe+0x49/0xbe

Accessing per-cpu variable should disable preemption, this patch extends the
preemption disable region for __this_cpu_read().

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Fixes: 52017608 ("KVM: nVMX: add option to perform early consistency checks via H/W")
Cc: stable@vger.kernel.org
Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

s390 does not have memremap, even though in this particular case it
would be useful.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>