Commit Graph

2112 Commits

Author SHA1 Message Date
Markus Armbruster
40c2281cc3 Drop more @errp parameters after previous commit
Several functions can't fail anymore: ich9_pm_add_properties(),
device_add_bootindex_property(), ppc_compat_add_property(),
spapr_caps_add_properties(), PropertyInfo.create().  Drop their @errp
parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-16-armbru@redhat.com>
2020-05-15 07:08:14 +02:00
Markus Armbruster
d2623129a7 qom: Drop parameter @errp of object_property_add() & friends
The only way object_property_add() can fail is when a property with
the same name already exists.  Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.

Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent.  Parentage is
also under program control, so this is a programming error, too.

We have a bit over 500 callers.  Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.

The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.

Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.  ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.

When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.

Drop parameter @errp and assert the preconditions instead.

There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification".  Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
2020-05-15 07:07:58 +02:00
Markus Armbruster
7eecec7d12 qom: Drop object_property_set_description() parameter @errp
object_property_set_description() and
object_class_property_set_description() fail only when property @name
is not found.

There are 85 calls of object_property_set_description() and
object_class_property_set_description().  None of them can fail:

* 84 immediately follow the creation of the property.

* The one in spapr_rng_instance_init() refers to a property created in
  spapr_rng_class_init(), from spapr_rng_properties[].

Every one of them still gets to decide what to pass for @errp.

51 calls pass &error_abort, 32 calls pass NULL, one receives the error
and propagates it to &error_abort, and one propagates it to
&error_fatal.  I'm actually surprised none of them violates the Error
API.

What are we gaining by letting callers handle the "property not found"
error?  Use when the property is not known to exist is simpler: you
don't have to guard the call with a check.  We haven't found such a
use in 5+ years.  Until we do, let's make life a bit simpler and drop
the @errp parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-8-armbru@redhat.com>
[One semantic rebase conflict resolved]
2020-05-15 07:06:49 +02:00
Markus Armbruster
ddfb0baaf2 qom: Clean up inconsistent use of gchar * vs. char *
Uses of gchar * in qom/object.h:

* ObjectProperty member @name

  Functions that take a property name argument all use char *.  Change
  the member to match.

* ObjectProperty member @type

  Functions that take a property type argument or return it all use
  char *.  Change the member to match.

* ObjectProperty member @description

  Functions that take a property description argument all use char *.
  Change the member to match.

* object_resolve_path_component() parameter @part

  Path components are property names.  Most callers pass char *
  arguments.  Change the parameter to match.  Adjust the few callers
  that pass gchar * to pass char *.

* Return value of object_get_canonical_path_component(),
  object_get_canonical_path()

  Most callers convert their return values right back to char *.
  Change the return value to match.  Adjust the few callers where that
  would add a conversion to gchar * to use char * instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-3-armbru@redhat.com>
2020-05-15 06:26:02 +02:00
Peter Maydell
b894c6ed4a ppc patch queue for 2020-04-07
First pull request for qemu-5.1.  This includes:
  * Removal of all remaining cases where we had CAS triggered reboots
  * A number of improvements to NMI injection
  * Support for partition scoped radix translation in softmmu
  * Some fixes for NVDIMM handling
  * A handful of other minor fixes
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Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-5.1-20200507' into staging

ppc patch queue for 2020-04-07

First pull request for qemu-5.1.  This includes:
 * Removal of all remaining cases where we had CAS triggered reboots
 * A number of improvements to NMI injection
 * Support for partition scoped radix translation in softmmu
 * Some fixes for NVDIMM handling
 * A handful of other minor fixes

# gpg: Signature made Thu 07 May 2020 06:00:55 BST
# 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-5.1-20200507:
  target-ppc: fix rlwimi, rlwinm, rlwnm for Clang-9
  spapr_nvdimm: Tweak error messages
  spapr_nvdimm.c: make 'label-size' mandatory
  target/ppc: Add support for Radix partition-scoped translation
  target/ppc: Rework ppc_radix64_walk_tree() for partition-scoped translation
  target/ppc: Extend ppc_radix64_check_prot() with a 'partition_scoped' bool
  target/ppc: Introduce ppc_radix64_xlate() for Radix tree translation
  spapr: Don't allow unplug of NVLink2 devices
  target/ppc: Assert if HV mode is set when running under a pseries machine
  target/ppc: Introduce a relocation bool in ppc_radix64_handle_mmu_fault()
  target/ppc: Enforce that the root page directory size must be at least 5
  spapr: Drop CAS reboot flag
  spapr/cas: Separate CAS handling from rebuilding the FDT
  spapr: Simplify selection of radix/hash during CAS
  ppc/pnv: Add support for NMI interface
  ppc/spapr: tweak change system reset helper
  spapr: Don't check capabilities removed between CAS calls
  target/ppc: Improve syscall exception logging

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-05-07 10:55:12 +01:00
David Gibson
6c0f0cb319 spapr_nvdimm: Tweak error messages
The restrictions here (which are checked at pre-plug time) are PAPR
specific, rather than being inherent to the NVDIMM devices.  Adjust the
error messages to be clearer about this.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
Daniel Henrique Barboza
70fc9cb092 spapr_nvdimm.c: make 'label-size' mandatory
The pseries machine does not support NVDIMM modules without label.
Attempting to do so, even if the overall block size is aligned with
256MB, will seg fault the guest kernel during NVDIMM probe. This
can be avoided by forcing 'label-size' to always be present for
sPAPR NVDIMMs.

The verification was put before the alignment check because the
presence of label-size affects the alignment calculation, so
it's not optimal to warn the user about an alignment error,
then about the lack of label-size, then about a new alignment
error when the user sets a label-size.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20200413203628.31636-1-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
David Gibson
05af7c77f5 spapr: Don't allow unplug of NVLink2 devices
Currently, we can't properly handle unplug of NVLink2 devices, because we
don't have code to tear down their special memory resources.  There's not
a lot of impetus to implement that: since hardware NVLink2 devices can't
be hot unplugged, the guest side drivers don't usually support unplug
anyway.

Therefore, simply prevent unplug of NVLink2 devices.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2020-05-07 11:10:50 +10:00
Greg Kurz
087820e37f spapr: Drop CAS reboot flag
The CAS reboot flag is false by default and all the locations that
could set it to true have been dropped. This means that all code
blocks depending on the flag being set is dead code and the other
code blocks should be executed always.

Just do that and drop the now uneeded CAS reboot flag. Fix a
comment on the way to make checkpatch happy.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <158514994893.478799.11772512888322840990.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
Alexey Kardashevskiy
91067db1ab spapr/cas: Separate CAS handling from rebuilding the FDT
At the moment "ibm,client-architecture-support" ("CAS") is implemented
in SLOF and QEMU assists via the custom H_CAS hypercall which copies
an updated flatten device tree (FDT) blob to the SLOF memory which
it then uses to update its internal tree.

When we enable the OpenFirmware client interface in QEMU, we won't need
to copy the FDT to the guest as the client is expected to fetch
the device tree using the client interface.

This moves FDT rebuild out to a separate helper which is going to be
called from the "ibm,client-architecture-support" handler and leaves
writing FDT to the guest in the H_CAS handler.

This should not cause any behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20200310050733.29805-3-aik@ozlabs.ru>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <158514994229.478799.2178881312094922324.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
Greg Kurz
b4b83312e7 spapr: Simplify selection of radix/hash during CAS
The guest can select the MMU mode by setting bits 0-1 of byte 24
in OV5 to to 0b00 for hash or 0b01 for radix. As required by the
architecture, we terminate the boot process if any other value
is found there.

The usual way to negotiate features in OV5 is basically ANDing
the bitfield provided by the guest and the bitfield of features
supported by QEMU, previously populated at machine init.

For some not documented reason, MMU is treated differently : bit 1
of byte 24 (the radix/hash bit) is cleared from the guest OV5 and
explicitely set in the final negotiated OV5 if radix was requested.

Since the only expected input from the guest is the radix/hash bit
being set or not, it seems more appropriate to handle this like we
do for XIVE.

Set the radix bit in spapr->ov5 at machine init if it has a chance
to work (ie. power9, either TCG or a radix capable KVM) and rely
exclusively on spapr_ovec_intersect() to set the radix bit in
spapr->ov5_cas.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <158514993621.478799.4204740354545734293.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
Nicholas Piggin
01b552b05b ppc/pnv: Add support for NMI interface
This implements the NMI interface for the PNV machine, similarly to
commit 3431648272 ("spapr: Add support for new NMI interface") for
SPAPR.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200325144147.221875-3-npiggin@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
Nicholas Piggin
b5b7f39181 ppc/spapr: tweak change system reset helper
Rather than have the helper take an optional vector address
override, instead have its caller modify env->nip itself.
This is more consistent when adding pnv nmi support, and also
with mce injection added later.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200325144147.221875-2-npiggin@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
Greg Kurz
86962462f8 spapr: Don't check capabilities removed between CAS calls
We currently check if some capability in OV5 was removed by the guest
since the previous CAS, and we trigger a CAS reboot in that case. This
was required because it could call for a device-tree property or node
removal, that we didn't support until recently (see commit 6787d27b04
"spapr: add option vector handling in CAS-generated resets" for details).

Now that we render a full FDT at CAS and that SLOF is able to handle
node removal, we don't need to do a CAS reset in this case anymore.
Also, this check can only return true if the guest has already called
CAS since the last full system reset (otherwise spapr->ov5_cas is
empty). Linux doesn't do that so this can be considered as dead code
for the vast majority of existing setups.

Drop the check. Since the only use of the ov5_cas_old variable is
precisely the check itself, drop the variable as well.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <158514993021.478799.10928618293640651819.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-05-07 11:10:50 +10:00
Cornelia Huck
541aaa1df8 hw: add compat machines for 5.1
Add 5.1 machine types for arm/i440fx/q35/s390x/spapr.

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-id: 20200429144605.7262-1-cohuck@redhat.com
2020-05-06 10:12:16 -04:00
Markus Armbruster
0f1eddf5ed bamboo, sam460ex: Tidy up error message for unsupported RAM size
Improve

    $ ppc-softmmu/qemu-system-ppc -M sam460ex -m 4096
    qemu-system-ppc: Max 1 banks of 2048 ,1024 ,512 ,256 ,128 ,64 ,32 MB DIMM/bank supported
    qemu-system-ppc: Possible valid RAM size: 2048

to

    qemu-system-ppc: at most 1 bank of 2048, 1024, 512, 256, 128, 64, 32 MiB each supported
    Possible valid RAM size: 1024 MiB

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200422134815.1584-4-armbru@redhat.com>
Reviewed-by: BALATON Zoltan <balaton@eik.bme.hu>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-04-29 08:01:52 +02:00
Markus Armbruster
f26740c61a smbus: Fix spd_data_generate() error API violation
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL.  Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call.

spd_data_generate() can pass @errp to error_setg() more than once when
it adjusts both memory size and type.  Harmless, because no caller
passes anything that needs adjusting.  Until the previous commit,
sam460ex passed types that needed adjusting, but not sizes.

spd_data_generate()'s contract is rather awkward:

    If everything's fine, return non-null and don't set an error.

    Else, if memory size or type need adjusting, return non-null and
    set an error describing the adjustment.

    Else, return null and set an error reporting why no data can be
    generated.

Its callers treat the error as a warning even when null is returned.
They don't create the "smbus-eeprom" device then.  Suspicious.

Since the previous commit, only "everything's fine" can actually
happen.  Drop the unused code and simplify the callers.  This gets rid
of the error API violation.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200422134815.1584-3-armbru@redhat.com>
2020-04-29 08:01:52 +02:00
Markus Armbruster
fc0cfc1dec sam460ex: Suppress useless warning on -m 32 and -m 64
Requesting 32 or 64 MiB of RAM with the sam460ex machine type produces
a useless warning:

    qemu-system-ppc: warning: Memory size is too small for SDRAM type, adjusting type

This is because sam460ex_init() asks spd_data_generate() for DDR2,
which is impossible, so spd_data_generate() corrects it to DDR.

The warning goes back to commit 08fd99179a "sam460ex: Clean up SPD
EEPROM creation".

Make sam460ex_init() pass the correct SDRAM type to get rid of the
warning.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20200422134815.1584-2-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-04-29 08:01:52 +02:00
Cédric Le Goater
25f3170b06 ppc/pnv: Create BMC devices only when defaults are enabled
Commit e2392d4395 ("ppc/pnv: Create BMC devices at machine init")
introduced default BMC devices which can be a problem when the same
devices are defined on the command line with :

  -device ipmi-bmc-sim,id=bmc0 -device isa-ipmi-bt,bmc=bmc0,irq=10

QEMU fails with :

  qemu-system-ppc64: error creating device tree: node: FDT_ERR_EXISTS

Use defaults_enabled() when creating the default BMC devices to let
the user provide its own BMC devices using '-nodefaults'. If no BMC
device are provided, output a warning but let QEMU run as this is a
supported configuration. However, when multiple BMC devices are
defined, stop QEMU with a clear error as the results are unexpected.

Fixes: e2392d4395 ("ppc/pnv: Create BMC devices at machine init")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20200404153655.166834-1-clg@kaod.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-04-07 08:55:11 +10:00
Peter Maydell
2025fc6766 hw/ppc/ppc440_uc.c: Remove incorrect iothread locking from dcr_write_pcie()
In dcr_write_pcie() we take the iothread lock around a call to
pcie_host_mmcfg_udpate().  This is an incorrect attempt to deal with
the bug fixed in commit 235352ee6e, where we were not taking
the iothread lock before calling device dcr read/write functions.
(It's not sufficient locking, because although the other cases in the
switch statement won't assert, there is no locking which prevents
multiple guest CPUs from trying to access the PPC460EXPCIEState
struct at the same time and corrupting data.)

Unfortunately with commit 235352ee6e we are now trying
to recursively take the iothread lock, which will assert:

  $ qemu-system-ppc -M sam460ex --display none
  **
  ERROR:/home/petmay01/linaro/qemu-from-laptop/qemu/cpus.c:1830:qemu_mutex_lock_iothread_impl: assertion failed: (!qemu_mutex_iothread_locked())
  Aborted (core dumped)

Remove the locking within dcr_write_pcie().

Fixes: 235352ee6e
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200330125228.24994-1-peter.maydell@linaro.org>
Tested-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-04-07 08:55:11 +10:00
David Gibson
7aab589976 spapr: Fix failure path for attempting to hot unplug PCI bridges
For various technical reasons we can't currently allow unplug a PCI to PCI
bridge on the pseries machine.  spapr_pci_unplug_request() correctly
generates an error message if that's attempted.

But.. if the given errp is not error_abort or error_fatal, it doesn't
actually stop trying to unplug the bridge anyway.

Fixes: 14e714900f "spapr: Allow hot plug/unplug of PCI bridges and devices under PCI bridges"
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2020-04-07 08:55:11 +10:00
Nicholas Piggin
4f7a11f93f ppc/spapr: Don't kill the guest if a recovered FWNMI machine check delivery fails
Try to be tolerant of FWNMI delivery errors if the machine check had been
recovered by the host.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200325142906.221248-5-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
[dwg: Updated comment at Greg's suggestion]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-04-07 08:55:10 +10:00
Nicholas Piggin
b90b9ecb12 ppc/spapr: Add FWNMI machine check delivery warnings
Add some messages which explain problems and guest misbehaviour that
may be difficult to diagnose in rare cases of machine checks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200325142906.221248-4-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-04-07 08:55:10 +10:00
Nicholas Piggin
6c3dd24c05 ppc/spapr: Improve FWNMI machine check delivery corner case comments
Some of the conditions are not as clearly documented as they could be.
Also the non-FWNMI case does not need a large comment.

Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200325142906.221248-3-npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-04-07 08:55:10 +10:00
Nicholas Piggin
ec010c0066 ppc/spapr: KVM FWNMI should not be enabled until guest requests it
The KVM FWNMI capability should be enabled with the "ibm,nmi-register"
rtas call. Although MCEs from KVM will be delivered as architected
interrupts to the guest before "ibm,nmi-register" is called, KVM has
different behaviour depending on whether the guest has enabled FWNMI
(it attempts to do more recovery on behalf of a non-FWNMI guest).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200325142906.221248-2-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-04-07 08:55:10 +10:00
Peter Maydell
3b4f50bd7d hw/ppc/e500.c: Handle qemu_find_file() failure
If qemu_find_file() doesn't find the BIOS it returns NULL; we were
passing that unchecked through to load_elf(), which assumes a non-NULL
pointer and may misbehave. In practice it fails with a weird message:

  $ qemu-system-ppc -M ppce500 -display none -kernel nonesuch
  Bad address
  qemu-system-ppc: could not load firmware '(null)'

Handle the failure case better:

  $ qemu-system-ppc -M ppce500 -display none -kernel nonesuch
  qemu-system-ppc: could not find firmware/kernel file 'nonesuch'

Spotted by Coverity (CID 1238954).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20200324121216.23899-1-peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-04-07 08:55:10 +10:00
Philippe Mathieu-Daudé
1583794b9b ppc/ppc405_boards: Remove unnecessary NULL check
This code is inside the "if (dinfo)" condition, so testing
again here whether it is NULL is unnecessary.

Fixes: dd59bcae7 (Don't size flash memory to match backing image)
Reported-by: Coverity (CID 1421917)
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200320155740.5342-1-philmd@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-24 11:56:37 +11:00
Greg Kurz
ce05fa0fcc spapr: Fix memory leak in h_client_architecture_support()
This is the only error path that needs to free the previously allocated
ov1.

Reported-by: Coverity (CID 1421924)
Fixes: cbd0d7f363 "spapr: Fail CAS if option vector table cannot be parsed"
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <158481206205.336182.16106097429336044843.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-03-24 11:56:37 +11:00
Mahesh Salgaonkar
cb9fb64d07 ppc/spapr: Set the effective address provided flag in mc error log.
Per PAPR, it is expected to set effective address provided flag in
sub_err_type member of mc extended error log (i.e
rtas_event_log_v6_mc.sub_err_type). This somehow got missed in original
fwnmi-mce patch series. The current code just updates the effective address
but does not set the flag to indicate that it is available. Hence guest
fails to extract effective address from mce rtas log. This patch fixes
that.

Without this patch guest MCE logs fails print DAR value:

[   11.933608] Disabling lock debugging due to kernel taint
[   11.933773] MCE: CPU0: machine check (Severe) Host TLB Multihit [Recovered]
[   11.933979] MCE: CPU0: NIP: [c000000000090b34] radix__flush_tlb_range_psize+0x194/0xf00
[   11.934223] MCE: CPU0: Initiator CPU
[   11.934341] MCE: CPU0: Unknown

After the change:

[   22.454149] Disabling lock debugging due to kernel taint
[   22.454316] MCE: CPU0: machine check (Severe) Host TLB Multihit DAR: deadbeefdeadbeef [Recovered]
[   22.454605] MCE: CPU0: NIP: [c0000000003e5804] kmem_cache_alloc+0x84/0x330
[   22.454820] MCE: CPU0: Initiator CPU
[   22.454944] MCE: CPU0: Unknown

Signed-off-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Message-Id: <158451653844.22972.17999316676230071087.stgit@jupiter>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-24 11:05:37 +11:00
Peter Maydell
ce73691e25 Pull request
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Merge remote-tracking branch 'remotes/jnsnow/tags/ide-pull-request' into staging

Pull request

# gpg: Signature made Tue 17 Mar 2020 23:22:33 GMT
# gpg:                using RSA key F9B7ABDBBCACDF95BE76CBD07DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>" [full]
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/ide-pull-request:
  hw/ide: Remove unneeded inclusion of hw/ide.h
  hw/ide: Move MAX_IDE_DEVS define to hw/ide/internal.h
  hw/ide: Do ide_drive_get() within pci_ide_create_devs()
  hw/ide/pci.c: Coding style update to fix checkpatch errors
  hw/ide: Remove now unneded #include "hw/pci/pci.h" from hw/ide.h
  hw/ide: Get rid of piix4_init function
  hw/isa/piix4.c: Introduce variable to store devfn
  hw/ide: Get rid of piix3_init functions
  hd-geo-test: Clean up use of buf[] in create_qcow2_with_mbr()
  via-ide: always use legacy IRQ 14/15 routing
  via-ide: allow guests to write to PCI_CLASS_PROG
  via-ide: initialise IDE controller in legacy mode
  via-ide: ensure that PCI_INTERRUPT_LINE is hard-wired to its default value
  pci: Honour wmask when resetting PCI_INTERRUPT_LINE
  ide/via: Get rid of via_ide_init()
  via-ide: move registration of VMStateDescription to DeviceClass
  cmd646: remove unused pci_cmd646_ide_init() function
  dp264: use pci_create_simple() to initialise the cmd646 device
  cmd646: register vmstate_ide_pci VMStateDescription in DeviceClass
  cmd646: register cmd646_reset() function in DeviceClass

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-03-19 11:14:24 +00:00
Peter Maydell
b319df5537 ppc patch queue 2020-03-17
Here's my final pull request for the qemu-5.0 soft freeze.  Sorry this
 is just under the wire - I hit some last minute problems that took a
 while to fix up and retest.
 
 Highlights are:
  * Numerous fixes for the FWNMI feature
  * A handful of cleanups to the device tree construction code
  * Numerous fixes for the spapr-vscsi device
  * A number of fixes and cleanups for real mode (MMU off) softmmu
    handling
  * Fixes for handling of the PAPR RMA
  * Better handling of hotplug/unplug events during boot
  * Assorted other fixes
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Merge remote-tracking branch 'remotes/dgibson/tags/ppc-for-5.0-20200317' into staging

ppc patch queue 2020-03-17

Here's my final pull request for the qemu-5.0 soft freeze.  Sorry this
is just under the wire - I hit some last minute problems that took a
while to fix up and retest.

Highlights are:
 * Numerous fixes for the FWNMI feature
 * A handful of cleanups to the device tree construction code
 * Numerous fixes for the spapr-vscsi device
 * A number of fixes and cleanups for real mode (MMU off) softmmu
   handling
 * Fixes for handling of the PAPR RMA
 * Better handling of hotplug/unplug events during boot
 * Assorted other fixes

# gpg: Signature made Tue 17 Mar 2020 09:55:07 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-5.0-20200317: (45 commits)
  pseries: Update SLOF firmware image
  ppc/spapr: Ignore common "ibm,nmi-interlock" Linux bug
  ppc/spapr: Implement FWNMI System Reset delivery
  target/ppc: allow ppc_cpu_do_system_reset to take an alternate vector
  ppc/spapr: Allow FWNMI on TCG
  ppc/spapr: Fix FWNMI machine check interrupt delivery
  ppc/spapr: Add FWNMI System Reset state
  ppc/spapr: Change FWNMI names
  ppc/spapr: Fix FWNMI machine check failure handling
  spapr: Rename DT functions to newer naming convention
  spapr: Move creation of ibm,architecture-vec-5 property
  spapr: Move creation of ibm,dynamic-reconfiguration-memory dt node
  spapr/rtas: Reserve space for RTAS blob and log
  pseries: Update SLOF firmware image
  ppc/spapr: Move GPRs setup to one place
  target/ppc: Fix rlwinm on ppc64
  spapr/xive: use SPAPR_IRQ_IPI to define IPI ranges exposed to the guest
  hw/scsi/spapr_vscsi: Convert debug fprintf() to trace event
  hw/scsi/spapr_vscsi: Prevent buffer overflow
  hw/scsi/spapr_vscsi: Do not mix SRP IU size with DMA buffer size
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2020-03-18 15:07:57 +00:00
BALATON Zoltan
7d0776ca7f hw/ide: Remove unneeded inclusion of hw/ide.h
After previous clean ups we can drop direct inclusion of hw/ide.h from
several places.

Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: a3f72b663e537701c63cec5fc9cb8ed4f4249f28.1584457537.git.balaton@eik.bme.hu
Signed-off-by: John Snow <jsnow@redhat.com>
2020-03-17 12:22:36 -04:00
Philippe Mathieu-Daudé
34b7645880 hw/ppc/ppc405: Use memory_region_init_rom() with read-only regions
The scripts/coccinelle/memory-region-housekeeping.cocci reported:
* TODO [[view:./hw/ppc/ppc405_boards.c::face=ovl-face1::linb=195::colb=8::cole=30][potential use of memory_region_init_rom*() in  ./hw/ppc/ppc405_boards.c::195]]
* TODO [[view:./hw/ppc/ppc405_boards.c::face=ovl-face1::linb=464::colb=8::cole=30][potential use of memory_region_init_rom*() in  ./hw/ppc/ppc405_boards.c::464]]

We can indeed replace the memory_region_init_ram() and
memory_region_set_readonly() calls by memory_region_init_rom().

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-03-17 15:18:49 +01:00
Philippe Mathieu-Daudé
1bbd95cb08 hw/ppc: Use memory_region_init_rom() with read-only regions
This commit was produced with the Coccinelle script
scripts/coccinelle/memory-region-housekeeping.cocci.

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-03-17 15:18:47 +01:00
Nicholas Piggin
75aa803835 ppc/spapr: Ignore common "ibm,nmi-interlock" Linux bug
Linux kernels call "ibm,nmi-interlock" in their system reset handlers
contrary to PAPR. Returning an error because the CPU does not hold the
interlock here causes Linux to print warning messages. PowerVM returns
success in this case, so do the same for now.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-9-npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
0e236d3477 ppc/spapr: Implement FWNMI System Reset delivery
PAPR requires that if "ibm,nmi-register" succeeds, then the hypervisor
delivers all system reset and machine check exceptions to the registered
addresses.

System Resets are delivered with registers set to the architected state,
and with no interlock.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-8-npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
9aa2528070 target/ppc: allow ppc_cpu_do_system_reset to take an alternate vector
Provide for an alternate delivery location, -1 defaults to the
architected address.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-7-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
89ba45652b ppc/spapr: Allow FWNMI on TCG
There should no longer be a reason to prevent TCG providing FWNMI.
System Reset interrupts are generated to the guest with nmi monitor
command and H_SIGNAL_SYS_RESET. Machine Checks can not be injected
currently, but this could be implemented with the mce monitor cmd
similarly to i386.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-6-npiggin@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
[dwg: Re-enable FWNMI in qtests, since that now works]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
ad77c6ca0c ppc/spapr: Fix FWNMI machine check interrupt delivery
FWNMI machine check delivery misses a few things that will make it fail
with TCG at least (which we would like to allow in future to improve
testing).

It's not nice to scatter interrupt delivery logic around the tree, so
move it to excp_helper.c and share code where possible.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-5-npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
edfdbf9c6b ppc/spapr: Add FWNMI System Reset state
The FWNMI option must deliver system reset interrupts to their
registered address, and there are a few constraints on the handler
addresses specified in PAPR. Add the system reset address state and
checks.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-4-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviwed-by: Mahesh Salgaonkar <mahesh@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
8af7e1fe6f ppc/spapr: Change FWNMI names
The option is called "FWNMI", and it involves more than just machine
checks, also machine checks can be delivered without the FWNMI option,
so re-name various things to reflect that.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-3-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:22 +11:00
Nicholas Piggin
bae9dc4f28 ppc/spapr: Fix FWNMI machine check failure handling
ppc_cpu_do_system_reset delivers a system rreset interrupt to the guest,
which is certainly not what is intended here. Panic the guest like other
failure cases here do.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20200316142613.121089-2-npiggin@gmail.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 17:00:21 +11:00
David Gibson
91335a5e15 spapr: Rename DT functions to newer naming convention
In the spapr code we've been gradually moving towards a convention that
functions which create pieces of the device tree are called spapr_dt_*().
This patch speeds that along by renaming most of the things that don't yet
match that so that they do.

For now we leave the *_dt_populate() functions which are actual methods
used in the DRCClass::dt_populate method.

While we're there we remove a few comments that don't really say anything
useful.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2020-03-17 17:00:19 +11:00
David Gibson
1e0e11085a spapr: Move creation of ibm,architecture-vec-5 property
This is currently called from spapr_dt_cas_updates() which is a hang
over from when we created this only as a diff to the DT at CAS time.
Now that we fully rebuild the DT at CAS time, just create it along
with the rest of the properties in /chosen.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2020-03-17 16:59:22 +11:00
David Gibson
fa523f0dd3 spapr: Move creation of ibm,dynamic-reconfiguration-memory dt node
Currently this node with information about hotpluggable memory is created
from spapr_dt_cas_updates().  But that's just a hangover from when we
created it only as a diff to the device tree at CAS time.  Now that we
fully rebuild the DT as CAS time, it makes more sense to create this along
with the rest of the memory information in the device tree.

So, move it to spapr_populate_memory().  The patch is huge, but it's nearly
all just code motion.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
2020-03-17 15:08:50 +11:00
Alexey Kardashevskiy
4dba872219 spapr/rtas: Reserve space for RTAS blob and log
At the moment SLOF reserves space for RTAS and instantiates the RTAS blob
which is 20 bytes binary blob calling an hypercall. The rest of the RTAS
area is a log which SLOF has no idea about but QEMU does.

This moves RTAS sizing to QEMU and this overrides the size from SLOF.
The only remaining problem is that SLOF copies the number of bytes it
reserved (2KB for now) so QEMU needs to reserve at least this much;
SLOF will be fixed separately to check that rtas-size from QEMU is
enough for those 20 bytes for the H_RTAS hcall.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20200316011841.99970-1-aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 15:08:50 +11:00
Alexey Kardashevskiy
395a20d3cc ppc/spapr: Move GPRs setup to one place
At the moment "pseries" starts in SLOF which only expects the FDT blob
pointer in r3. As we are going to introduce a OpenFirmware support in
QEMU, we will be booting OF clients directly and these expect a stack
pointer in r1, Linux looks at r3/r4 for the initramdisk location
(although vmlinux can find this from the device tree but zImage from
distro kernels cannot).

This extends spapr_cpu_set_entry_state() to take more registers. This
should cause no behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20200310050733.29805-2-aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-03-17 15:08:50 +11:00
David Gibson
425f0b7adb spapr: Clean up RMA size calculation
Move the calculation of the Real Mode Area (RMA) size into a helper
function.  While we're there clean it up and correct it in a few ways:
  * Add comments making it clearer where the various constraints come from
  * Remove a pointless check that the RMA fits within Node 0 (we've just
    clamped it so that it does)

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-03-17 15:08:47 +11:00
David Gibson
1052ab67f4 spapr: Don't clamp RMA to 16GiB on new machine types
In spapr_machine_init() we clamp the size of the RMA to 16GiB and the
comment saying why doesn't make a whole lot of sense.  In fact, this was
done because the real mode handling code elsewhere limited the RMA in TCG
mode to the maximum value configurable in LPCR[RMLS], 16GiB.

But,
 * Actually LPCR[RMLS] has been able to encode a 256GiB size for a very
   long time, we just didn't implement it properly in the softmmu
 * LPCR[RMLS] shouldn't really be relevant anyway, it only was because we
   used to abuse the RMOR based translation mode in order to handle the
   fact that we're not modelling the hypervisor parts of the cpu

We've now removed those limitations in the modelling so the 16GiB clamp no
longer serves a function.  However, we can't just remove the limit
universally: that would break migration to earlier qemu versions, where
the 16GiB RMLS limit still applies, no matter how bad the reasons for it
are.

So, we replace the 16GiB clamp, with a clamp to a limit defined in the
machine type class.  We set it to 16 GiB for machine types 4.2 and earlier,
but set it to 0 meaning unlimited for the new 5.0 machine type.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2020-03-17 09:41:15 +11:00
David Gibson
8897ea5a9f spapr: Don't attempt to clamp RMA to VRMA constraint
The Real Mode Area (RMA) is the part of memory which a guest can access
when in real (MMU off) mode.  Of course, for a guest under KVM, the MMU
isn't really turned off, it's just in a special translation mode - Virtual
Real Mode Area (VRMA) - which looks like real mode in guest mode.

The mechanics of how this works when using the hash MMU (HPT) put a
constraint on the size of the RMA, which depends on the size of the
HPT.  So, the latter part of spapr_setup_hpt_and_vrma() clamps the RMA
we advertise to the guest based on this VRMA limit.

There are several things wrong with this:
 1) spapr_setup_hpt_and_vrma() doesn't actually clamp, it takes the minimum
    of Node 0 memory size and the VRMA limit.  That will *often* work the
    same as clamping, but there can be other constraints on RMA size which
    supersede Node 0 memory size.  We have real bugs caused by this
    (currently worked around in the guest kernel)
 2) Some callers of spapr_setup_hpt_and_vrma() are in a situation where
    we're past the point that we can actually advertise an RMA limit to the
    guest
 3) But most fundamentally, the VRMA limit depends on host configuration
    (page size) which shouldn't be visible to the guest, but this partially
    exposes it.  This can cause problems with migration in certain edge
    cases, although we will mostly get away with it.

In practice, this clamping is almost never applied anyway.  With 64kiB
pages and the normal rules for sizing of the HPT, the theoretical VRMA
limit will be 4x(guest memory size) and so never hit.  It will hit with
4kiB pages, where it will be (guest memory size)/4.  However all mainstream
distro kernels for POWER have used a 64kiB page size for at least 10 years.

So, simply replace this logic with a check that the RMA we've calculated
based only on guest visible configuration will fit within the host implied
VRMA limit.  This can break if running HPT guests on a host kernel with
4kiB page size.  As noted that's very rare.  There also exist several
possible workarounds:
  * Change the host kernel to use 64kiB pages
  * Use radix MMU (RPT) guests instead of HPT
  * Use 64kiB hugepages on the host to back guest memory
  * Increase the guest memory size so that the RMA hits one of the fixed
    limits before the RMA limit.  This is relatively easy on POWER8 which
    has a 16GiB limit, harder on POWER9 which has a 1TiB limit.
  * Use a guest NUMA configuration which artificially constrains the RMA
    within the VRMA limit (the RMA must always fit within Node 0).

Previously, on KVM, we also temporarily reduced the rma_size to 256M so
that the we'd load the kernel and initrd safely, regardless of the VRMA
limit.  This was a) confusing, b) could significantly limit the size of
images we could load and c) introduced a behavioural difference between
KVM and TCG.  So we remove that as well.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
2020-03-17 09:41:15 +11:00