Commit Graph

68 Commits

Author SHA1 Message Date
Nicholas Piggin
dc5e072188 spapr: TCG allow up to 8-thread SMT on POWER8 and newer CPUs
PPC TCG supports SMT CPU configurations for non-hypervisor state, so
permit POWER8-10 pseries machines to enable SMT.

This requires PIR and TIR be set, because that's how sibling thread
matching is done by TCG.

spapr's nested-HV capability does not currently coexist with SMT, so
that combination is prohibited (interestingly somewhat analogous to
LPAR-per-core mode on real hardware which also does not support KVM).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
[ clg: Also test smp_threads when checking for POWER8 CPU and above ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2023-06-25 22:41:30 +02:00
Nicholas Piggin
ccc5a4c5e1 spapr: Add SPAPR_CAP_AIL_MODE_3 for AIL mode 3 support for H_SET_MODE hcall
The behaviour of the Address Translation Mode on Interrupt resource is
not consistently supported by all CPU versions or all KVM versions: KVM
HV does not support mode 2, and does not support mode 3 on POWER7 or
early POWER9 processesors. KVM PR only supports mode 0. TCG supports all
modes (0, 2, 3) on CPUs with support for the corresonding LPCR[AIL] mode.
This leads to inconsistencies in guest behaviour and could cause problems
migrating guests.

This was not noticable for Linux guests for a long time because the
kernel only uses modes 0 and 3, and it used to consider AIL-3 to be
advisory in that it would always keep the AIL-0 vectors around, so it
did not matter whether or not interrupts were delivered according to
the AIL mode. Recent Linux guests depend on AIL mode 3 working as
specified in order to support the SCV facility interrupt. If AIL-3 can
not be provided, then H_SET_MODE must return an error to Linux so it can
disable the SCV facility (failure to do so can lead to userspace being
able to crash the guest kernel).

Add the ail-mode-3 capability to specify that AIL-3 is supported. AIL-0
is implied as the baseline, and AIL-2 is no longer supported by spapr.
AIL-2 is not known to be used by any software, but support in TCG could
be restored with an ail-mode-2 capability quite easily if a regression
is reported.

Modify the H_SET_MODE Address Translation Mode on Interrupt resource
handler to check capabilities and correctly return error if not
supported.

KVM has a cap to advertise support for AIL-3.

Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20230515160216.394612-1-npiggin@gmail.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
2023-05-28 07:13:54 -03:00
Dr. David Alan Gilbert
118d4ed045 Trivial: 3 char repeat typos
Inspired by Julia Lawall's fixing of Linux
kernel comments, I looked at qemu, although I did it manually.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Klaus Jensen <k.jensen@samsung.com>
Message-Id: <20220614104045.85728-2-dgilbert@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2022-06-28 11:06:02 +02:00
Daniel Henrique Barboza
37d1953448 hw/ppc/spapr_caps.c: use g_autofree in spapr_caps_add_properties()
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220228175004.8862-6-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2022-03-02 06:51:39 +01:00
Daniel Henrique Barboza
bc940c46c9 hw/ppc/spapr_caps.c: use g_autofree in spapr_cap_get_string()
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220228175004.8862-5-danielhb413@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2022-03-02 06:51:39 +01:00
Daniel Henrique Barboza
ea8464fa27 hw/ppc/spapr_caps.c: use g_autofree in spapr_cap_set_string()
And get rid of the 'out' label since it's now unused.

Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20220228175004.8862-4-danielhb413@gmail.com>
[ clg: Fixed typo in commit log ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2022-03-02 06:51:39 +01:00
Nicholas Piggin
120f738a46 spapr: implement nested-hv capability for the virtual hypervisor
This implements the Nested KVM HV hcall API for spapr under TCG.

The L2 is switched in when the H_ENTER_NESTED hcall is made, and the
L1 is switched back in returned from the hcall when a HV exception
is sent to the vhyp. Register state is copied in and out according to
the nested KVM HV hcall API specification.

The hdecr timer is started when the L2 is switched in, and it provides
the HDEC / 0x980 return to L1.

The MMU re-uses the bare metal radix 2-level page table walker by
using the get_pate method to point the MMU to the nested partition
table entry. MMU faults due to partition scope errors raise HV
exceptions and accordingly are routed back to the L1.

The MMU does not tag translations for the L1 (direct) vs L2 (nested)
guests, so the TLB is flushed on any L1<->L2 transition (hcall entry
and exit).

Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
[ clg: checkpatch fixes ]
Message-Id: <20220216102545.1808018-10-npiggin@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
2022-02-18 08:34:14 +01:00
Bharata B Rao
82123b756a target/ppc: Support for H_RPT_INVALIDATE hcall
If KVM_CAP_RPT_INVALIDATE KVM capability is enabled, then

- indicate the availability of H_RPT_INVALIDATE hcall to the guest via
  ibm,hypertas-functions property.
- Enable the hcall

Both the above are done only if the new sPAPR machine capability
cap-rpt-invalidate is set.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Message-Id: <20210706112440.1449562-3-bharata@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2021-07-09 11:01:06 +10:00
Lucas Mateus Castro (alqotel)
fd1eb085da target/ppc: moved function out of mmu-hash64
The function ppc_hash64_filter_pagesizes has been moved from a function
with prototype in mmu-hash64.h and implemented in mmu-hash64.c to
a static function in hw/ppc/spapr_caps.c as it's only used in that file.

Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Message-Id: <20210506163941.106984-3-lucas.araujo@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2021-05-19 10:30:28 +10:00
Chen Qun
d6eb39b554 qtest: delete superfluous inclusions of qtest.h
There are 23 files that include the "sysemu/qtest.h",
but they do not use any qtest functions.

Signed-off-by: Chen Qun <kuhn.chenqun@huawei.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210226081414.205946-1-kuhn.chenqun@huawei.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2021-03-09 06:03:53 +01:00
Greg Kurz
35dce34fbc spapr: Add a return value to spapr_check_pagesize()
As recommended in "qapi/error.h", return true on success and false on
failure. This allows to reduce error propagation overhead in the callers.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200914123505.612812-14-groug@kaod.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-10-09 10:15:06 +11:00
Greg Kurz
19d55e2031 spapr: Forbid nested KVM-HV in pre-power9 compat mode
Nested KVM HV only works if the kernel is using the radix MMU mode, ie.
the CPU is POWER9 and it is not running in some pre-power9 compat mode.
Otherwise, the KVM HV module fails to load in the guest with -ENODEV.
It might be painful for a user to discover this late that nested cannot
work with their setup. Erroring out at machine init instead seems to be
the best we can do.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <159491948127.188975.9621435875869177751.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-08-12 13:16:27 +10:00
Greg Kurz
d9c5b5fa86 spapr: Use error_append_hint() in spapr_caps.c
We have a dedicated error API for hints. Use it instead of embedding
the hint in the error message, as recommanded in the "qapi/error.h"
header file.

While here, have cap_fwnmi_apply(), which already uses
error_append_hint(), to call ERRP_GUARD() as well.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <159594297421.8262.14314530897345809924.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-08-12 13:16:27 +10:00
Markus Armbruster
668f62ec62 error: Eliminate error_propagate() with Coccinelle, part 1
When all we do with an Error we receive into a local variable is
propagating to somewhere else, we can just as well receive it there
right away.  Convert

    if (!foo(..., &err)) {
        ...
        error_propagate(errp, err);
        ...
        return ...
    }

to

    if (!foo(..., errp)) {
        ...
        ...
        return ...
    }

where nothing else needs @err.  Coccinelle script:

    @rule1 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
         if (
    (
    -        fun(args, &err, args2)
    +        fun(args, errp, args2)
    |
    -        !fun(args, &err, args2)
    +        !fun(args, errp, args2)
    |
    -        fun(args, &err, args2) op c1
    +        fun(args, errp, args2) op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    )
         }

    @rule2 forall@
    identifier fun, err, errp, lbl;
    expression list args, args2;
    expression var;
    binary operator op;
    constant c1, c2;
    symbol false;
    @@
    -    var = fun(args, &err, args2);
    +    var = fun(args, errp, args2);
         ... when != err
         if (
    (
             var
    |
             !var
    |
             var op c1
    )
            )
         {
             ... when != err
                 when != lbl:
                 when strict
    -        error_propagate(errp, err);
             ... when != err
    (
             return;
    |
             return c2;
    |
             return false;
    |
             return var;
    )
         }

    @depends on rule1 || rule2@
    identifier err;
    @@
    -    Error *err = NULL;
         ... when != err

Not exactly elegant, I'm afraid.

The "when != lbl:" is necessary to avoid transforming

         if (fun(args, &err)) {
             goto out
         }
         ...
     out:
         error_propagate(errp, err);

even though other paths to label out still need the error_propagate().
For an actual example, see sclp_realize().

Without the "when strict", Coccinelle transforms vfio_msix_setup(),
incorrectly.  I don't know what exactly "when strict" does, only that
it helps here.

The match of return is narrower than what I want, but I can't figure
out how to express "return where the operand doesn't use @err".  For
an example where it's too narrow, see vfio_intx_enable().

Silently fails to convert hw/arm/armsse.c, because Coccinelle gets
confused by ARMSSE being used both as typedef and function-like macro
there.  Converted manually.

Line breaks tidied up manually.  One nested declaration of @local_err
deleted manually.  Preexisting unwanted blank line dropped in
hw/riscv/sifive_e.c.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20200707160613.848843-35-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Markus Armbruster
62a35aaa31 qapi: Use returned bool to check for failure, Coccinelle part
The previous commit enables conversion of

    visit_foo(..., &err);
    if (err) {
        ...
    }

to

    if (!visit_foo(..., errp)) {
        ...
    }

for visitor functions that now return true / false on success / error.
Coccinelle script:

    @@
    identifier fun =~ "check_list|input_type_enum|lv_start_struct|lv_type_bool|lv_type_int64|lv_type_str|lv_type_uint64|output_type_enum|parse_type_bool|parse_type_int64|parse_type_null|parse_type_number|parse_type_size|parse_type_str|parse_type_uint64|print_type_bool|print_type_int64|print_type_null|print_type_number|print_type_size|print_type_str|print_type_uint64|qapi_clone_start_alternate|qapi_clone_start_list|qapi_clone_start_struct|qapi_clone_type_bool|qapi_clone_type_int64|qapi_clone_type_null|qapi_clone_type_number|qapi_clone_type_str|qapi_clone_type_uint64|qapi_dealloc_start_list|qapi_dealloc_start_struct|qapi_dealloc_type_anything|qapi_dealloc_type_bool|qapi_dealloc_type_int64|qapi_dealloc_type_null|qapi_dealloc_type_number|qapi_dealloc_type_str|qapi_dealloc_type_uint64|qobject_input_check_list|qobject_input_check_struct|qobject_input_start_alternate|qobject_input_start_list|qobject_input_start_struct|qobject_input_type_any|qobject_input_type_bool|qobject_input_type_bool_keyval|qobject_input_type_int64|qobject_input_type_int64_keyval|qobject_input_type_null|qobject_input_type_number|qobject_input_type_number_keyval|qobject_input_type_size_keyval|qobject_input_type_str|qobject_input_type_str_keyval|qobject_input_type_uint64|qobject_input_type_uint64_keyval|qobject_output_start_list|qobject_output_start_struct|qobject_output_type_any|qobject_output_type_bool|qobject_output_type_int64|qobject_output_type_null|qobject_output_type_number|qobject_output_type_str|qobject_output_type_uint64|start_list|visit_check_list|visit_check_struct|visit_start_alternate|visit_start_list|visit_start_struct|visit_type_.*";
    expression list args;
    typedef Error;
    Error *err;
    @@
    -    fun(args, &err);
    -    if (err)
    +    if (!fun(args, &err))
         {
             ...
         }

A few line breaks tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-19-armbru@redhat.com>
2020-07-10 15:18:08 +02:00
Greg Kurz
a816f2d6b8 spapr: Simplify some warning printing paths in spapr_caps.c
We obviously only want to print a warning in these cases, but this is done
in a rather convoluted manner. Just use warn_report() instead.

Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <159188281098.70166.18387926536399257573.stgit@bahia.lan>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-06-26 09:22:29 +10:00
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
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
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
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
Aravinda Prasad
f03496bc12 ppc: spapr: Handle "ibm,nmi-register" and "ibm,nmi-interlock" RTAS calls
This patch adds support in QEMU to handle "ibm,nmi-register"
and "ibm,nmi-interlock" RTAS calls.

The machine check notification address is saved when the
OS issues "ibm,nmi-register" RTAS call.

This patch also handles the case when multiple processors
experience machine check at or about the same time by
handling "ibm,nmi-interlock" call. In such cases, as per
PAPR, subsequent processors serialize waiting for the first
processor to issue the "ibm,nmi-interlock" call. The second
processor that also received a machine check error waits
till the first processor is done reading the error log.
The first processor issues "ibm,nmi-interlock" call
when the error log is consumed.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
[Register fwnmi RTAS calls in core_rtas_register_types()
 where other RTAS calls are registered]
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Message-Id: <20200130184423.20519-6-ganeshgr@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-03 11:33:11 +11:00
Aravinda Prasad
9d953ce447 ppc: spapr: Introduce FWNMI capability
Introduce fwnmi an spapr capability and add a helper function
which tries to enable it, which would be used by following patch
of the series. This patch by itself does not change the existing
behavior.

Signed-off-by: Aravinda Prasad <arawinda.p@gmail.com>
[eliminate cap_ppc_fwnmi, add fwnmi cap to migration state
 and reprhase the commit message]
Signed-off-by: Ganesh Goudar <ganeshgr@linux.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20200130184423.20519-3-ganeshgr@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2020-02-03 11:33:10 +11:00
David Gibson
37965dfe4d spapr: Enable DD2.3 accelerated count cache flush in pseries-5.0 machine
For POWER9 DD2.2 cpus, the best current Spectre v2 indirect branch
mitigation is "count cache disabled", which is configured with:
    -machine cap-ibs=fixed-ccd
However, this option isn't available on DD2.3 CPUs with KVM, because they
don't have the count cache disabled.

For POWER9 DD2.3 cpus, it is "count cache flush with assist", configured
with:
    -machine cap-ibs=workaround,cap-ccf-assist=on
However this option isn't available on DD2.2 CPUs with KVM, because they
don't have the special CCF assist instruction this relies on.

On current machine types, we default to "count cache flush w/o assist",
that is:
    -machine cap-ibs=workaround,cap-ccf-assist=off
This runs, with mitigation on both DD2.2 and DD2.3 host cpus, but has a
fairly significant performance impact.

It turns out we can do better.  The special instruction that CCF assist
uses to trigger a count cache flush is a no-op on earlier CPUs, rather than
trapping or causing other badness.  It doesn't, of itself, implement the
mitigation, but *if* we have count-cache-disabled, then the count cache
flush is unnecessary, and so using the count cache flush mitigation is
harmless.

Therefore for the new pseries-5.0 machine type, enable cap-ccf-assist by
default.  Along with that, suppress throwing an error if cap-ccf-assist
is selected but KVM doesn't support it, as long as KVM *is* giving us
count-cache-disabled.  To allow TCG to work out of the box, even though it
doesn't implement the ccf flush assist, downgrade the error in that case to
a warning.  This matches several Spectre mitigations where we allow TCG
to operate for debugging, since we don't really make guarantees about TCG
security properties anyway.

While we're there, make the TCG warning for this case match that for other
mitigations.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: Michael Ellerman <mpe@ellerman.id.au>
2020-02-03 11:33:02 +11:00
Shivaprasad G Bhat
d758880586 ppc: fix memory leak in spapr_caps_add_properties
Free the capability name string after setting
the capability.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <156335156198.82682.8756968724044750843.stgit@lep8c.aus.stglabs.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-08-21 17:17:11 +10:00
Daniel Black
f92be77fea spapr: quantify error messages regarding capability settings
Its not immediately obvious how cap-X=Y setting need to be applied
to the command line so, for spapr capability error messages, this
has been clarified to:

 appending -machine cap-X=Y

The wrong value messages have been left as is, as the user has found
the right location.

Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Daniel Black <daniel@linux.ibm.com>
Message-Id: <20190812071044.30806-1-daniel@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-08-21 11:32:11 +10:00
Markus Armbruster
d645427057 Include migration/vmstate.h less
In my "build everything" tree, changing migration/vmstate.h triggers a
recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).

hw/hw.h supposedly includes it for convenience.  Several other headers
include it just to get VMStateDescription.  The previous commit made
that unnecessary.

Include migration/vmstate.h only where it's still needed.  Touching it
now recompiles only some 1600 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-16-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Markus Armbruster
14a48c1d0d qemu-common: Move tcg_enabled() etc. to sysemu/tcg.h
Other accelerators have their own headers: sysemu/hax.h, sysemu/hvf.h,
sysemu/kvm.h, sysemu/whpx.h.  Only tcg_enabled() & friends sit in
qemu-common.h.  This necessitates inclusion of qemu-common.h into
headers, which is against the rules spelled out in qemu-common.h's
file comment.

Move tcg_enabled() & friends into their own header sysemu/tcg.h, and
adjust #include directives.

Cc: Richard Henderson <rth@twiddle.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190523143508.25387-2-armbru@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
[Rebased with conflicts resolved automatically, except for
accel/tcg/tcg-all.c]
2019-06-11 20:22:09 +02:00
Greg Kurz
3725ef1a94 spapr: Don't migrate the hpt_maxpagesize cap to older machine types
Commit 0b8c89be7f7b added the hpt_maxpagesize capability to the migration
stream. This is okay for new machine types but it breaks backward migration
to older QEMUs, which don't expect the extra subsection.

Add a compatibility boolean flag to the sPAPR machine class and use it to
skip migration of the capability for machine types 4.0 and older. This
fixes migration to an older QEMU. Note that the destination will emit a
warning:

qemu-system-ppc64: warning: cap-hpt-max-page-size lower level (16) in incoming stream than on destination (24)

This is expected and harmless though. It is okay to migrate from a lower
HPT maximum page size (64k) to a greater one (16M).

Fixes: 0b8c89be7f7b "spapr: Add forgotten capability to migration stream"
Based-on: <20190522074016.10521-3-clg@kaod.org>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <155853262675.1158324.17301777846476373459.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-05-29 11:39:47 +10:00
David Gibson
64d4a53431 spapr: Add forgotten capability to migration stream
spapr machine capabilities are supposed to be sent in the migration stream
so that we can sanity check the source and destination have compatible
configuration.  Unfortunately, when we added the hpt-max-page-size
capability, we forgot to add it to the migration state.  This means that we
can generate spurious warnings when both ends are configured for large
pages, or potentially fail to warn if the source is configured for huge
pages, but the destination is not.

Fixes: 2309832afd "spapr: Maximum (HPT) pagesize property"

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2019-05-29 11:39:45 +10:00
David Hildenbrand
905b7ee4d6 exec: Introduce qemu_maxrampagesize() and rename qemu_getrampagesize()
Rename qemu_getrampagesize() to qemu_minrampagesize(). While at it,
properly rename find_max_supported_pagesize() to
find_min_backend_pagesize().

s390x is actually interested into the maximum ram pagesize, so
introduce and use qemu_maxrampagesize().

Add a TODO, indicating that looking at any mapped memory backends is not
100% correct in some cases.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20190417113143.5551-3-david@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
2019-04-25 13:47:27 +02:00
David Gibson
ce2918cbc3 spapr: Use CamelCase properly
The qemu coding standard is to use CamelCase for type and structure names,
and the pseries code follows that... sort of.  There are quite a lot of
places where we bend the rules in order to preserve the capitalization of
internal acronyms like "PHB", "TCE", "DIMM" and most commonly "sPAPR".

That was a bad idea - it frequently leads to names ending up with hard to
read clusters of capital letters, and means they don't catch the eye as
type identifiers, which is kind of the point of the CamelCase convention in
the first place.

In short, keeping type identifiers look like CamelCase is more important
than preserving standard capitalization of internal "words".  So, this
patch renames a heap of spapr internal type names to a more standard
CamelCase.

In addition to case changes, we also make some other identifier renames:
  VIOsPAPR* -> SpaprVio*
    The reverse word ordering was only ever used to mitigate the capital
    cluster, so revert to the natural ordering.
  VIOsPAPRVTYDevice -> SpaprVioVty
  VIOsPAPRVLANDevice -> SpaprVioVlan
    Brevity, since the "Device" didn't add useful information
  sPAPRDRConnector -> SpaprDrc
  sPAPRDRConnectorClass -> SpaprDrcClass
    Brevity, and makes it clearer this is the same thing as a "DRC"
    mentioned in many other places in the code

This is 100% a mechanical search-and-replace patch.  It will, however,
conflict with essentially any and all outstanding patches touching the
spapr code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 14:33:05 +11:00
Suraj Jitindar Singh
006e9d3618 target/ppc/tcg: make spapr_caps apply cap-[cfpc/sbbc/ibs] non-fatal for tcg
The spapr_caps cap-cfpc, cap-sbbc and cap-ibs are used to control the
availability of certain mitigations to the guest. These haven't been
implemented under TCG, it is unlikely they ever will be, and it is unclear
as to whether they even need to be.

As such, make failure to apply these capabilities under TCG non-fatal.
Instead we print a warning message to the user but still allow the guest
to continue.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301044609.9626-2-sjitindarsingh@gmail.com>
[dwg: Small style fix]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 14:32:54 +11:00
Suraj Jitindar Singh
8ff43ee404 target/ppc/spapr: Add SPAPR_CAP_CCF_ASSIST
Introduce a new spapr_cap SPAPR_CAP_CCF_ASSIST to be used to indicate
the requirement for a hw-assisted version of the count cache flush
workaround.

The count cache flush workaround is a software workaround which can be
used to flush the count cache on context switch. Some revisions of
hardware may have a hardware accelerated flush, in which case the
software flush can be shortened. This cap is used to set the
availability of such hardware acceleration for the count cache flush
routine.

The availability of such hardware acceleration is indicated by the
H_CPU_CHAR_BCCTR_FLUSH_ASSIST flag being set in the characteristics
returned from the KVM_PPC_GET_CPU_CHAR ioctl.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301031912.28809-2-sjitindarsingh@gmail.com>
[dwg: Small style fixes]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
399b2896d4 target/ppc/spapr: Add workaround option to SPAPR_CAP_IBS
The spapr_cap SPAPR_CAP_IBS is used to indicate the level of capability
for mitigations for indirect branch speculation. Currently the available
values are broken (default), fixed-ibs (fixed by serialising indirect
branches) and fixed-ccd (fixed by diabling the count cache).

Introduce a new value for this capability denoted workaround, meaning that
software can work around the issue by flushing the count cache on
context switch. This option is available if the hypervisor sets the
H_CPU_BEHAV_FLUSH_COUNT_CACHE flag in the cpu behaviours returned from
the KVM_PPC_GET_CPU_CHAR ioctl.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301031912.28809-1-sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
edaa799559 target/ppc/spapr: Enable the large decrementer for pseries-4.0
Enable the large decrementer by default for the pseries-4.0 machine type.
It is disabled again by default_caps_with_cpu() for pre-POWER9 cpus
since they don't support the large decrementer.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301024317.22137-4-sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
7d050527e3 target/ppc: Implement large decrementer support for KVM
Implement support to allow KVM guests to take advantage of the large
decrementer introduced on POWER9 cpus.

To determine if the host can support the requested large decrementer
size, we check it matches that specified in the ibm,dec-bits device-tree
property. We also need to enable it in KVM by setting the LPCR_LD bit in
the LPCR. Note that to do this we need to try and set the bit, then read
it back to check the host allowed us to set it, if so we can use it but
if we were unable to set it the host cannot support it and we must not
use the large decrementer.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190301024317.22137-3-sjitindarsingh@gmail.com>
[dwg: Small style fixes]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
a8dafa5251 target/ppc: Implement large decrementer support for TCG
Prior to POWER9 the decrementer was a 32-bit register which decremented
with each tick of the timebase. From POWER9 onwards the decrementer can
be set to operate in a mode called large decrementer where it acts as a
n-bit decrementing register which is visible as a 64-bit register, that
is the value of the decrementer is sign extended to 64 bits (where n is
implementation dependant).

The mode in which the decrementer operates is controlled by the LPCR_LD
bit in the logical paritition control register (LPCR).

>From POWER9 onwards the HDEC (hypervisor decrementer) was enlarged to
h-bits, also sign extended to 64 bits (where h is implementation
dependant). Note this isn't configurable and is always enabled.

On POWER9 the large decrementer and hdec are both 56 bits, as
represented by the lrg_decr_bits cpu class property. Since they are the
same size we only add one property for now, which could be extended in
the case they ever differ in the future.

We also add the lrg_decr_bits property for POWER5+/7/8 since it is used
to determine the size of the hdec, which is only generated on the
POWER5+ processor and later. On these processors it is 32 bits.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190301024317.22137-2-sjitindarsingh@gmail.com>
[dwg: Small style fixes]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
c982f5cf9a target/ppc/spapr: Add SPAPR_CAP_LARGE_DECREMENTER
Add spapr_cap SPAPR_CAP_LARGE_DECREMENTER to be used to control the
availability of the large decrementer for a guest.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Message-Id: <20190301024317.22137-1-sjitindarsingh@gmail.com>
[dwg: Trivial style fix]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-03-12 12:07:49 +11:00
Suraj Jitindar Singh
b9a477b725 ppc/spapr_caps: Add SPAPR_CAP_NESTED_KVM_HV
Add the spapr cap SPAPR_CAP_NESTED_KVM_HV to be used to control the
availability of nested kvm-hv to the level 1 (L1) guest.

Assuming a hypervisor with support enabled an L1 guest can be allowed to
use the kvm-hv module (and thus run it's own kvm-hv guests) by setting:
-machine pseries,cap-nested-hv=true
or disabled with:
-machine pseries,cap-nested-hv=false

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-11-08 13:08:35 +11:00
Greg Kurz
e89372951d spapr: compute default value of "hpt-max-page-size" later
It is currently not possible to run a pseries-2.12 or older machine
with HV KVM. QEMU prints the following and exits right away.

qemu-system-ppc64: KVM doesn't support for base page shift 34

The "hpt-max-page-size" capability was recently added to spapr to hide
host configuration details from HPT mode guests. Its default value for
newer machine types is 64k.

For backwards compatibility, pseries-2.12 and older machine types need
a different value. This is handled as usual in a class init function.
The default value is 16G, ie, all page sizes supported by POWER7 and
newer CPUs, but HV KVM requires guest pages to be hpa contiguous as
well as gpa contiguous. The default value is the page size used to
back the guest RAM in this case.

Unfortunately kvmppc_hpt_needs_host_contiguous_pages()->kvm_enabled() is
called way before KVM init and returns false, even if the user requested
KVM. We thus end up selecting 16G, which isn't supported by HV KVM. The
default value must be set during machine init, because we can safely
assume that KVM is initialized at this point.

We fix this by moving the logic to default_caps_with_cpu(). Since the
user cannot pass cap-hpt-max-page-size=0, we set the default to 0 in
the pseries-2.12 class init function and use that as a flag to do the
real work.

Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-07-03 10:20:15 +10:00
David Gibson
9dceda5fc3 spapr: Limit available pagesizes to provide a consistent guest environment
KVM HV has some limitations (deriving from the hardware) that mean not all
host-cpu supported pagesizes may be usable in the guest.  At present this
means that KVM guests and TCG guests may see different available page sizes
even if they notionally have the same vcpu model.  This is confusing and
also prevents migration between TCG and KVM.

This patch makes the environment consistent by always allowing the same set
of pagesizes.  Since we can't remove the KVM limitations, we do this by
always applying the same limitations it has, even to TCG guests.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-06-22 14:19:07 +10:00
David Gibson
123eec6552 spapr: Use maximum page size capability to simplify memory backend checking
The way we used to handle KVM allowable guest pagesizes for PAPR guests
required some convoluted checking of memory attached to the guest.

The allowable pagesizes advertised to the guest cpus depended on the memory
which was attached at boot, but then we needed to ensure that any memory
later hotplugged didn't change which pagesizes were allowed.

Now that we have an explicit machine option to control the allowable
maximum pagesize we can simplify this.  We just check all memory backends
against that declared pagesize.  We check base and cold-plugged memory at
reset time, and hotplugged memory at pre_plug() time.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-06-22 14:19:07 +10:00
David Gibson
2309832afd spapr: Maximum (HPT) pagesize property
The way the POWER Hash Page Table (HPT) MMU is virtualized by KVM HV means
that every page that the guest puts in the pagetables must be truly
physically contiguous, not just GPA-contiguous.  In effect this means that
an HPT guest can't use any pagesizes greater than the host page size used
to back its memory.

At present we handle this by changing what we advertise to the guest based
on the backing pagesizes.  This is pretty bad, because it means the guest
sees a different environment depending on what should be host configuration
details.

As a start on fixing this, we add a new capability parameter to the
pseries machine type which gives the maximum allowed pagesizes for an
HPT guest.  For now we just create and validate the parameter without
making it do anything.

For backwards compatibility, on older machine types we set it to the max
available page size for the host.  For the 3.0 machine type, we fix it to
16, the intention being to only allow HPT pagesizes up to 64kiB by default
in future.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
2018-06-22 14:19:07 +10:00
David Gibson
e2e4f64118 spapr: Add cpu_apply hook to capabilities
spapr capabilities have an apply hook to actually activate (or deactivate)
the feature in the system at reset time.  However, a number of capabilities
affect the setup of cpus, and need to be applied to each of them -
including hotplugged cpus for extra complication.  To make this simpler,
add an optional cpu_apply hook that is called from spapr_cpu_reset().

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2018-06-21 21:22:53 +10:00
David Gibson
9f6edd066e spapr: Compute effective capability values earlier
Previously, the effective values of the various spapr capability flags
were only determined at machine reset time.  That was a lazy way of making
sure it was after cpu initialization so it could use the cpu object to
inform the defaults.

But we've now improved the compat checking code so that we don't need to
instantiate the cpus to use it.  That lets us move the resolution of the
capability defaults much earlier.

This is going to be necessary for some future capabilities.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2018-06-21 21:22:53 +10:00
David Gibson
ad99d04c76 target/ppc: Allow cpu compatiblity checks based on type, not instance
ppc_check_compat() is used in a number of places to check if a cpu object
supports a certain compatiblity mode, subject to various constraints.

It takes a PowerPCCPU *, however it really only depends on the cpu's class.
We have upcoming cases where it would be useful to make compatibility
checks before we fully instantiate the cpu objects.

ppc_type_check_compat() will now make an equivalent check, but based on a
CPU's QOM typename instead of an instantiated CPU object.

We make use of the new interface in several places in spapr, where we're
essentially making a global check, rather than one specific to a particular
cpu.  This avoids some ugly uses of first_cpu to grab a "representative"
instance.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
2018-06-21 21:22:53 +10:00
Suraj Jitindar Singh
b2540203bd ppc/spapr_caps: Don't disable cap_cfpc on POWER8 by default
In default_caps_with_cpu() we set spapr_cap_cfpc to broken for POWER8
processors and before.

Since we no longer require private l1d cache on POWER8 for this cap to
be set to workaround change this to default to broken for POWER7
processors and before.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-06-16 16:32:33 +10:00
Suraj Jitindar Singh
813f3cf655 ppc/spapr-caps: Define the pseries-2.12-sxxm machine type
The sxxm (speculative execution exploit mitigation) machine type is a
variant of the 2.12 machine type with workarounds for speculative
execution vulnerabilities enabled by default.

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2018-03-06 13:16:29 +11:00