We need to be able to use OHCISysBusState outside hcd-ohci.c, so move it
to its include file.
Reviewed-by: NGerd Hoffmann <kraxel@redhat.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Tested-by: NNiek Linnenbank <nieklinnenbank@gmail.com>
Message-id: 20200217204812.9857-2-linux@roeck-us.net
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The ACTLR2 and HACTLR2 AArch32 system registers didn't exist in ARMv7
or the original ARMv8.  They were later added as optional registers,
whose presence is signaled by the ID_MMFR4.AC2 field.  From ARMv8.2
they are mandatory (ie ID_MMFR4.AC2 must be non-zero).

We implemented HACTLR2 in commit 0e0456ab, but we
incorrectly made it exist for all v8 CPUs, and we didn't implement
ACTLR2 at all.

Sort this out by implementing both registers only when they are
supposed to exist, and setting the ID_MMFR4 bit for -cpu max.

Note that this removes HACTLR2 from our Cortex-A53, -A47 and -A72
CPU models; this is correct, because those CPUs do not implement
this register.

Fixes: 0e0456abSigned-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-22-peter.maydell@linaro.org

Cut-and-paste errors mean we're using FIELD_EX64() to extract fields from
some 32-bit ID register fields. Use FIELD_EX32() instead. (This makes
no difference in behaviour, it's just more consistent.)
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-21-peter.maydell@linaro.org

Now we have moved ID_MMFR4 into the ARMISARegisters struct, we
can define and use an isar_feature for the presence of the
ARMv8.2-AA32HPD feature, rather than open-coding the test.

While we're here, correct a comment typo which missed an 'A'
from the feature name.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-20-peter.maydell@linaro.org

The isar_feature_aa32_pan and isar_feature_aa32_ats1e1 functions
are supposed to be testing fields in ID_MMFR3; but a cut-and-paste
error meant we were looking at MVFR0 instead.

Fix the functions to look at the right register; this requires
us to move at least id_mmfr3 to the ARMISARegisters struct; we
choose to move all the ID_MMFRn registers for consistency.

Fixes: 3d6ad6bbSigned-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-19-peter.maydell@linaro.org

The LC bit in the PMCR_EL0 register is supposed to be:
 * read/write
 * RES1 on an AArch64-only implementation
 * an architecturally UNKNOWN value on reset
(and use of LC==0 by software is deprecated).

We were implementing it incorrectly as read-only always zero,
though we do have all the code needed to test it and behave
accordingly.

Instead make it a read-write bit which resets to 1 always, which
satisfies all the architectural requirements above.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-18-peter.maydell@linaro.org

The PMCR_EL0.DP bit is bit 5, which is 0x20, not 0x10.  0x10 is 'X'.
Correct our #define of PMCRDP and add the missing PMCRX.

We do have the correct behaviour for handling the DP bit being
set, so this fixes a guest-visible bug.

Fixes: 033614c4Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-17-peter.maydell@linaro.org

Set the ID register bits to provide ARMv8.4-PMU (and implicitly
also ARMv8.1-PMU) in the 'max' CPU.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-16-peter.maydell@linaro.org

The ARMv8.4-PMU extension adds:
 * one new required event, STALL
 * one new system register PMMIR_EL1

(There are also some more L1-cache related events, but since
we don't implement any cache we don't provide these, in the
same way we don't provide the base-PMUv3 cache events.)

The STALL event "counts every attributable cycle on which no
attributable instruction or operation was sent for execution on this
PE".  QEMU doesn't stall in this sense, so this is another
always-reads-zero event.

The PMMIR_EL1 register is a read-only register providing
implementation-specific information about the PMU; currently it has
only one field, SLOTS, which defines behaviour of the STALL_SLOT PMU
event.  Since QEMU doesn't implement the STALL_SLOT event, we can
validly make the register read zero.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-15-peter.maydell@linaro.org

The ARMv8.1-PMU extension requires:
 * the evtCount field in PMETYPER<n>_EL0 is 16 bits, not 10
 * MDCR_EL2.HPMD allows event counting to be disabled at EL2
 * two new required events, STALL_FRONTEND and STALL_BACKEND
 * ID register bits in ID_AA64DFR0_EL1 and ID_DFR0

We already implement the 16-bit evtCount field and the
HPMD bit, so all that is missing is the two new events:
  STALL_FRONTEND
   "counts every cycle counted by the CPU_CYCLES event on which no
    operation was issued because there are no operations available
    to issue to this PE from the frontend"
  STALL_BACKEND
   "counts every cycle counted by the CPU_CYCLES event on which no
    operation was issued because the backend is unable to accept
    any available operations from the frontend"

QEMU never stalls in this sense, so our implementation is trivial:
always return a zero count.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-14-peter.maydell@linaro.org

Now we have isar_feature test functions that look at fields in the
ID_AA64DFR0_EL1 and ID_DFR0 ID registers, add the code that reads
these register values from KVM so that the checks behave correctly
when we're using KVM.

No isar_feature function tests ID_AA64DFR1_EL1 or DBGDIDR yet, but we
add it to maintain the invariant that every field in the
ARMISARegisters struct is populated for a KVM CPU and can be relied
on.  This requirement isn't actually written down yet, so add a note
to the relevant comment.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-13-peter.maydell@linaro.org

We're going to want to read the DBGDIDR register from KVM in
a subsequent commit, which means it needs to be in the
ARMISARegisters sub-struct. Move it.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-12-peter.maydell@linaro.org

The AArch32 DBGDIDR defines properties like the number of
breakpoints, watchpoints and context-matching comparators.  On an
AArch64 CPU, the register may not even exist if AArch32 is not
supported at EL1.

Currently we hard-code use of DBGDIDR to identify the number of
breakpoints etc; this works for all our TCG CPUs, but will break if
we ever add an AArch64-only CPU.  We also have an assert() that the
AArch32 and AArch64 registers match, which currently works only by
luck for KVM because we don't populate either of these ID registers
from the KVM vCPU and so they are both zero.

Clean this up so we have functions for finding the number
of breakpoints, watchpoints and context comparators which look
in the appropriate ID register.

This allows us to drop the "check that AArch64 and AArch32 agree
on the number of breakpoints etc" asserts:
 * we no longer look at the AArch32 versions unless that's the
   right place to be looking
 * it's valid to have a CPU (eg AArch64-only) where they don't match
 * we shouldn't have been asserting the validity of ID registers
   in a codepath used with KVM anyway
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-11-peter.maydell@linaro.org

Add the 64-bit version of the "is this a v8.1 PMUv3?"
ID register check function, and the _any_ version that
checks for either AArch32 or AArch64 support. We'll use
this in a later commit.

We don't (yet) do any isar_feature checks on ID_AA64DFR1_EL1,
but we move id_aa64dfr1 into the ARMISARegisters struct with
id_aa64dfr0, for consistency.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-10-peter.maydell@linaro.org

Instead of open-coding a check on the ID_DFR0 PerfMon ID register
field, create a standardly-named isar_feature for "does AArch32 have
a v8.1 PMUv3" and use it.

This entails moving the id_dfr0 field into the ARMISARegisters struct.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-9-peter.maydell@linaro.org

We already define FIELD macros for ID_DFR0, so use them in the
one place where we're doing direct bit value manipulation.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-8-peter.maydell@linaro.org

Add FIELD() definitions for the ID_AA64DFR0_EL1 and use them
where we currently have hard-coded bit values.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-7-peter.maydell@linaro.org

Pull the code that defines the various PMU registers out
into its own function, matching the pattern we have
already for the debug registers.

Apart from one style fix to a multi-line comment, this
is purely movement of code with no changes to it.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-6-peter.maydell@linaro.org

Instead of open-coding "ARM_FEATURE_AARCH64 ? aa64_predinv: aa32_predinv",
define and use an any_predinv isar_feature test function.
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-5-peter.maydell@linaro.org

Our current usage of the isar_feature feature tests almost always
uses an _aa32_ test when the code path is known to be AArch32
specific and an _aa64_ test when the code path is known to be
AArch64 specific. There is just one exception: in the vfp_set_fpscr
helper we check aa64_fp16 to determine whether the FZ16 bit in
the FP(S)CR exists, but this code is also used for AArch32.
There are other places in future where we're likely to want
a general "does this feature exist for either AArch32 or
AArch64" check (typically where architecturally the feature exists
for both CPU states if it exists at all, but the CPU might be
AArch32-only or AArch64-only, and so only have one set of ID
registers).

Introduce a new category of isar_feature_* functions:
isar_feature_any_foo() should be tested when what we want to
know is "does this feature exist for either AArch32 or AArch64",
and always returns the logical OR of isar_feature_aa32_foo()
and isar_feature_aa64_foo().
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-4-peter.maydell@linaro.org

In take_aarch32_exception(), we know we are dealing with a CPU that
has AArch32, so the right isar_feature test is aa32_pan, not aa64_pan.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214175116.9164-3-peter.maydell@linaro.org

Enforce a convention that an isar_feature function that tests a
32-bit ID register always has _aa32_ in its name, and one that
tests a 64-bit ID register always has _aa64_ in its name.
We already follow this except for three cases: thumb_div,
arm_div and jazelle, which all need _aa32_ adding.

(As noted in the comment, isar_feature_aa32_fp16_arith()
is an exception in that it currently tests ID_AA64PFR0_EL1,
but will switch to MVFR1 once we've properly implemented
FP16 for AArch32.)
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200214175116.9164-2-peter.maydell@linaro.org

For the purpose of rebuild_hflags_a64, we do not need to compute
all of the va parameters, only tbi.  Moreover, we can compute them
in a form that is more useful to storing in hflags.

This eliminates the need for aa64_va_parameter_both, so fold that
in to aa64_va_parameter.  The remaining calls to aa64_va_parameter
are in get_phys_addr_lpae and in pauth_helper.c.

This reduces the total cpu consumption of aa64_va_parameter in a
kernel boot plus a kvm guest kernel boot from 3% to 0.5%.
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200216194343.21331-5-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Now that aa64_va_parameters_both sets select based on the number
of ranges in the regime, the ttbr1_valid check is redundant.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200216194343.21331-4-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Select should always be 0 for a regime with one range.
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200216194343.21331-3-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The psuedocode in aarch64/functions/pac/auth/Auth and
aarch64/functions/pac/strip/Strip always uses bit 55 for
extfield and do not consider if the current regime has 2 ranges.
Suggested-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 20200216194343.21331-2-richard.henderson@linaro.org
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Writes to AdvSIMD registers flush the bits above 128.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214194643.23317-5-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Writes to AdvSIMD registers flush the bits above 128.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214194643.23317-4-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Writes to AdvSIMD registers flush the bits above 128.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214194643.23317-3-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Writes to AdvSIMD registers flush the bits above 128.

Buglink: https://bugs.launchpad.net/bugs/1863247Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-id: 20200214194643.23317-2-richard.henderson@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Up to now, the z2 machine only boots if a flash image is provided.
This is not really necessary; the machine can boot from initrd or from
SD without it. At the same time, having to provide dummy flash images
is a nuisance and does not add any real value. Make it optional.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200217210903.18602-1-linux@roeck-us.net
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Up to now, the mainstone machine only boots if two flash images are
provided. This is not really necessary; the machine can boot from initrd
or from SD without it. At the same time, having to provide dummy flash
images is a nuisance and does not add any real value. Make it optional.
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200217210824.18513-1-linux@roeck-us.net
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Fix warning reported by Clang static code analyzer:

    CC      hw/misc/iotkit-secctl.o
  hw/misc/iotkit-secctl.c:343:9: warning: Value stored to 'value' is never read
          value &= 0x00f000f3;
          ^        ~~~~~~~~~~

Fixes: b3717c23
Reported-by: Clang Static Analyzer
Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20200217132922.24607-1-f4bug@amsat.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This returns a fixed but non-zero value for the chip id.
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Reviewed-by: NAndrew Jeffery <andrew@aj.id.au>
Reviewed-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200121013302.43839-3-joel@jms.id.au
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This splits the common write callback into separate ast2400 and ast2500
implementations. This makes it clearer when implementing differing
behaviour.
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Reviewed-by: NAndrew Jeffery <andrew@aj.id.au>
Reviewed-by: NCédric Le Goater <clg@kaod.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20200121013302.43839-2-joel@jms.id.au
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

ppc patch queue 2020-02-21

Here's the next patch of ppc target patches.  Highlights are:
  * Some fixes for CAS / unplug interactions
  * Remove some leaks of device trees
  * Some fixes for the PHB3 and PHB4 devices
  * Support for NVDIMMs on the pseries machine type
  * Assorted other fixes and cleanups

# gpg: Signature made Fri 21 Feb 2020 03:35:40 GMT
# gpg:                using RSA key 75F46586AE61A66CC44E87DC6C38CACA20D9B392
# gpg: Good signature from "David Gibson <david@gibson.dropbear.id.au>" [full]
# gpg:                 aka "David Gibson (Red Hat) <dgibson@redhat.com>" [full]
# gpg:                 aka "David Gibson (ozlabs.org) <dgibson@ozlabs.org>" [full]
# gpg:                 aka "David Gibson (kernel.org) <dwg@kernel.org>" [unknown]
# Primary key fingerprint: 75F4 6586 AE61 A66C C44E  87DC 6C38 CACA 20D9 B392

* remotes/dgibson/tags/ppc-for-5.0-20200221:
  hw/ppc/virtex_ml507:fix leak of fdevice tree blob
  spapr: Fix handling of unplugged devices during CAS and migration
  spapr: Don't use spapr_drc_needed() in CAS code
  ppc: free 'fdt' after reset the machine
  target/ppc/cpu.h: Clean up comments in the struct CPUPPCState definition
  target/ppc/cpu.h: Move fpu related members closer in cpu env
  target/ppc: Fix typo in comments
  spapr: Allow changing offset for -kernel image
  pnv/phb3: Add missing break statement
  pnv/phb4: Fix error path in pnv_pec_realize()
  pnv/phb3: Convert 1u to 1ull
  target/ppc/cpu.h: Remove duplicate includes
  spapr: Add Hcalls to support PAPR NVDIMM device
  spapr: Add NVDIMM device support
  nvdimm: add uuid property to nvdimm
  mem: move nvdimm_device_list to utilities
  ppc: function to setup latest class options
  ppc/pnv: Fix PCI_EXPRESS dependency
  qtest: Fix rtas dependencies
  spapr/rtas: Print message from "ibm,os-term"
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Block patches:
- qemu-img convert: New --target-is-zero parameter
- qcow2: Specify non-default compression type flag
- optionally flat output for query-named-block-nodes
- some fixes
- pseudo-creation of images on block devices is now done by a generic
  block layer function

# gpg: Signature made Thu 20 Feb 2020 16:05:34 GMT
# gpg:                using RSA key 91BEB60A30DB3E8857D11829F407DB0061D5CF40
# gpg:                issuer "mreitz@redhat.com"
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>" [full]
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/maxreitz/tags/pull-block-2020-02-20:
  iotests: Test snapshot -l field separation
  block: Fix VM size field width in snapshot dump
  iotests: Test convert -n -B to backing-less target
  qemu-img: Fix convert -n -B for backing-less targets
  iotests: Add test for image creation fallback
  iscsi: Drop iscsi_co_create_opts()
  file-posix: Drop hdev_co_create_opts()
  block: Generic file creation fallback
  block/nbd: Fix hang in .bdrv_close()
  iotests/279: Fix for non-qcow2 formats
  block/backup-top: fix flags handling
  block: always fill entire LUKS header space with zeros
  qemu-img: Add --target-is-zero to convert
  qapi: Allow getting flat output from 'query-named-block-nodes'
  iotests/147: Fix drive parameters
  iotests: Remove the superfluous 2nd check for the availability of quorum
  docs: qcow2: introduce compression type feature
  docs: improve qcow2 spec about extending image header
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The device tree blob returned by load_device_tree is malloced.
We should free it after cpu_physical_memory_write().
Reported-by: NEuler Robot <euler.robot@huawei.com>
Signed-off-by: NChen Qun <kuhn.chenqun@huawei.com>
Message-Id: <20200218091154.21696-3-kuhn.chenqun@huawei.com>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

We already detect if a device is being hot plugged before CAS to trigger
a CAS reboot and during migration to migrate the state of the associated
DRC. But hot unplugging a device is also an asynchronous operation that
requires the guest to take action. This means that if the guest is migrated
after the hot unplug event was sent but before it could release the device
with RTAS, the destination QEMU doesn't know about the pending unplug
operation and doesn't actually remove the device when the guest finally
releases it.

Similarly, if the unplug request is fired before CAS, the guest isn't
notified of the change, just like with hotplug. It ends up booting with
the device still present in the DT and configures it, just like it was
never removed. Even weirder, since the event is still queued, it will
be eventually processed when some other unrelated event is posted to
the guest.

Enhance spapr_drc_transient() to also return true if an unplug request is
pending. This fixes the issue at CAS with a CAS reboot request and
causes the DRC state to be migrated. Some extra care is still needed to
inform the destination that an unplug request is pending : migrate the
unplug_requested field of the DRC in an optional subsection. This might
break backwards migration, but this is still better than ending with
an inconsistent guest.
Signed-off-by: NGreg Kurz <groug@kaod.org>
Message-Id: <158169248798.3465937.1108351365840514270.stgit@bahia.lan>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>

We currently don't support hotplug of devices between boot and CAS. If
this happens a CAS reboot is triggered. We detect this during CAS using
the spapr_drc_needed() function which is essentially a VMStateDescription
.needed callback. Even if the condition for CAS reboot happens to be the
same as for DRC migration, it looks wrong to piggyback a migration helper
for this.

Introduce a helper with slightly more explicit name and use it in both CAS
and DRC migration code. Since a subsequent patch will enhance this helper
to cover the case of hot unplug, let's go for spapr_drc_transient(). While
here convert spapr_hotplugged_dev_before_cas() to the "transient" wording as
well.

This doesn't change any behaviour.
Signed-off-by: NGreg Kurz <groug@kaod.org>
Message-Id: <158169248180.3465937.9531405453362718771.stgit@bahia.lan>
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>