It's generic enough to be used from the XIVE2 router and avoid more
duplication.
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20210809134547.689560-9-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
These will be shared with the XIVE2 router.
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20210809134547.689560-8-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
When the QEMU PowerNV machine was introduced, multi chip support
modeled a two socket system with dual chip modules as found on some P8
Tuleta systems (8286-42A). But this is hardly used and not relevant
for QEMU. Use a simple index instead.
With this change, we can now increase the max socket number to 16 as
found on high end systems.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20210809134547.689560-5-clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There is no need to keep the DD1 chip model as it will never be
publicly available.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20210809134547.689560-3-clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Coverity reported issues which are caused by mixing of signed return codes
from DTC and unsigned return codes of the client interface.
This introduces PROM_ERROR and makes distinction between the error types.
This fixes NEGATIVE_RETURNS, OVERRUN issues reported by Coverity.
This adds a comment about the return parameters number in the VOF hcall.
The reason for such counting is to keep the numbers look the same in
vof_client_handle() and the Linux (an OF client).
vmc->client_architecture_support() returns target_ulong and we want to
propagate this to the client (for example H_MULTI_THREADS_ACTIVE).
The VOF path to do_client_architecture_support() needs chopping off
the top 32bit but SLOF's H_CAS does not; and either way the return values
are either 0 or 32bit negative error code. For now this chops
the top 32bits.
This makes "claim" fail if the allocated address is above 4GB as
the client interface is 32bit. This still allows claiming memory above
4GB as potentially initrd can be put there and the client can read
the address from the FDT's "available" property.
Fixes: CID 1458139, 1458138, 1458137, 1458133, 1458132
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20210720050726.2737405-1-aik@ozlabs.ru>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
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>
This addresses the comments from v22.
The functional changes are (the VOF ones need retesting with Pegasos2):
(VOF) setprop will start failing if the machine class callback
did not handle it;
(VOF) unit addresses are lowered in path_offset();
(SPAPR) /chosen/bootargs is initialized from kernel_cmdline if
the client did not change it.
Fixes: 5c991e5d4378 ("spapr: Implement Open Firmware client interface")
Cc: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20210708065625.548396-1-aik@ozlabs.ru>
Tested-by: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There are several new L1D cache flush bits added to the hcall which reflect
hardware security features for speculative cache access issues.
These behaviours are now being specified as negative in order to simplify
patched kernel compatibility with older firmware (a new problem found in
existing systems would automatically be vulnerable).
[dwg: Technically this changes behaviour for existing machine types.
After discussion with Nick, we've determined this is safe, because
the worst that will happen if a guest gets the wrong information due
to a migration is that it will perform some unnecessary workarounds,
but will remain correct and secure (well, as secure as it was going
to be anyway). In addition the change only affects cap-cfpc=safe
which is not enabled by default, and in fact is not possible to set
on any current hardware (though it's expected it will be possible on
POWER10)]
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20210615044107.1481608-1-npiggin@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The PAPR platform describes an OS environment that's presented by
a combination of a hypervisor and firmware. The features it specifies
require collaboration between the firmware and the hypervisor.
Since the beginning, the runtime component of the firmware (RTAS) has
been implemented as a 20 byte shim which simply forwards it to
a hypercall implemented in qemu. The boot time firmware component is
SLOF - but a build that's specific to qemu, and has always needed to be
updated in sync with it. Even though we've managed to limit the amount
of runtime communication we need between qemu and SLOF, there's some,
and it has become increasingly awkward to handle as we've implemented
new features.
This implements a boot time OF client interface (CI) which is
enabled by a new "x-vof" pseries machine option (stands for "Virtual Open
Firmware). When enabled, QEMU implements the custom H_OF_CLIENT hcall
which implements Open Firmware Client Interface (OF CI). This allows
using a smaller stateless firmware which does not have to manage
the device tree.
The new "vof.bin" firmware image is included with source code under
pc-bios/. It also includes RTAS blob.
This implements a handful of CI methods just to get -kernel/-initrd
working. In particular, this implements the device tree fetching and
simple memory allocator - "claim" (an OF CI memory allocator) and updates
"/memory@0/available" to report the client about available memory.
This implements changing some device tree properties which we know how
to deal with, the rest is ignored. To allow changes, this skips
fdt_pack() when x-vof=on as not packing the blob leaves some room for
appending.
In absence of SLOF, this assigns phandles to device tree nodes to make
device tree traversing work.
When x-vof=on, this adds "/chosen" every time QEMU (re)builds a tree.
This adds basic instances support which are managed by a hash map
ihandle -> [phandle].
Before the guest started, the used memory is:
0..e60 - the initial firmware
8000..10000 - stack
400000.. - kernel
3ea0000.. - initramdisk
This OF CI does not implement "interpret".
Unlike SLOF, this does not format uninitialized nvram. Instead, this
includes a disk image with pre-formatted nvram.
With this basic support, this can only boot into kernel directly.
However this is just enough for the petitboot kernel and initradmdisk to
boot from any possible source. Note this requires reasonably recent guest
kernel with:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=df5be5be8735
The immediate benefit is much faster booting time which especially
crucial with fully emulated early CPU bring up environments. Also this
may come handy when/if GRUB-in-the-userspace sees light of the day.
This separates VOF and sPAPR in a hope that VOF bits may be reused by
other POWERPC boards which do not support pSeries.
This assumes potential support for booting from QEMU backends
such as blockdev or netdev without devices/drivers used.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20210625055155.2252896-1-aik@ozlabs.ru>
Reviewed-by: BALATON Zoltan <balaton@eik.bme.hu>
[dwg: Adjusted some includes which broke compile in some more obscure
compilation setups]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
QEMU reserves space for RTAS via /rtas/rtas-size which tells the client
how much space the RTAS requires to work which includes the RTAS binary
blob implementing RTAS runtime. Because pseries supports FWNMI which
requires plenty of space, QEMU reserves more than 2KB which is
enough for the RTAS blob as it is just 20 bytes (under QEMU).
Since FWNMI reset delivery was added, RTAS_SIZE macro is not used anymore.
This replaces RTAS_SIZE with RTAS_MIN_SIZE and uses it in
the /rtas/rtas-size calculation to account for the RTAS blob.
Fixes: 0e236d3477 ("ppc/spapr: Implement FWNMI System Reset delivery")
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20210622070336.1463250-1-aik@ozlabs.ru>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The subsequent patches add definitions which tend to get
the compilation to cyclic dependency. So, prepare with
forward declarations, move the definitions and clean up.
Signed-off-by: Shivaprasad G Bhat <sbhat@linux.ibm.com>
Message-Id: <162133925415.610.11584121797866216417.stgit@4f1e6f2bd33e>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
QEMU 6.0 moved all the -boot variables to the machine. Especially, the
removal of the boot_order static changed the handling of '-boot once'
from:
if (boot_once) {
qemu_boot_set(boot_once, &error_fatal);
qemu_register_reset(restore_boot_order, g_strdup(boot_order));
}
to
if (current_machine->boot_once) {
qemu_boot_set(current_machine->boot_once, &error_fatal);
qemu_register_reset(restore_boot_order,
g_strdup(current_machine->boot_order));
}
This means that we now register as subsequent boot order a copy
of current_machine->boot_once that was just set with the previous
call to qemu_boot_set(), i.e. we never transition away from the
once boot order.
It is certainly fragile^Wwrong for the spapr code to hijack a
field of the base machine type object like that. The boot order
rework simply turned this software boundary violation into an
actual bug.
Have the spapr code to handle that with its own field in
SpaprMachineState. Also kfree() the initial boot device
string when "once" was used.
Fixes: 4b7acd2ac8 ("vl: clean up -boot variables")
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1960119
Cc: pbonzini@redhat.com
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210521160735.1901914-1-groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The hypercalls h_enter, h_remove, h_bulk_remove, h_protect, and h_read,
have been moved to spapr_softmmu.c with the functions they depend on. The
functions is_ram_address and push_sregs_to_kvm_pr are not static anymore
as functions on both spapr_hcall.c and spapr_softmmu.c depend on them.
The hypercalls h_resize_hpt_prepare and h_resize_hpt_commit have been
divided, the KVM part stayed in spapr_hcall.c while the softmmu part
was moved to spapr_softmmu.c
Signed-off-by: Lucas Mateus Castro (alqotel) <lucas.araujo@eldorado.org.br>
Message-Id: <20210506163941.106984-2-lucas.araujo@eldorado.org.br>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
A following patch will make use of it.
Signed-off-by: Fabiano Rosas <farosas@linux.ibm.com>
Message-Id: <20210505001130.3999968-2-farosas@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Certain SMP topologies stress, e.g. 1 thread/core, 2048 cores and
1 socket, stress the current maximum size of the pSeries FDT:
Calling ibm,client-architecture-support...qemu-system-ppc64: error
creating device tree: (fdt_setprop(fdt, offset,
"ibm,processor-segment-sizes", segs, sizeof(segs))): FDT_ERR_NOSPACE
2048 is the default NR_CPUS value for the pSeries kernel. It's expected
that users will want QEMU to be able to handle this kind of
configuration.
Bumping FDT_MAX_SIZE to 2MB is enough for these setups to be created.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210408204049.221802-3-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Power10 is introducing second DAWR. Use real register names (with
suffix 0) from ISA for current macros and variables used by Qemu.
One exception to this is KVM_REG_PPC_DAWR[X]. This is from kernel
uapi header and thus not changed in kernel as well as Qemu.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20210412114433.129702-3-ravi.bangoria@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Add support for H_SCM_HEALTH hcall described at [1] for spapr
nvdimms. This enables guest to detect the 'unarmed' status of a
specific spapr nvdimm identified by its DRC and if its unarmed, mark
the region backed by the nvdimm as read-only.
The patch adds h_scm_health() to handle the H_SCM_HEALTH hcall which
returns two 64-bit bitmaps (health bitmap, health bitmap mask) derived
from 'struct nvdimm->unarmed' member.
Linux kernel side changes to enable handling of 'unarmed' nvdimms for
ppc64 are proposed at [2].
References:
[1] "Hypercall Op-codes (hcalls)"
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/powerpc/papr_hcalls.rst#n220
[2] "powerpc/papr_scm: Mark nvdimm as unarmed if needed during probe"
https://lore.kernel.org/linux-nvdimm/20210329113103.476760-1-vaibhav@linux.ibm.com/
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Message-Id: <20210402102128.213943-1-vaibhav@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The pseries machines introduced the concept of 'unplug timeout' for CPU
hotunplugs. The idea was to circunvent a deficiency in the pSeries
specification (PAPR), that currently does not define a proper way for
the hotunplug to fail. If the guest refuses to release the CPU (see [1]
for an example) there is no way for QEMU to detect the failure.
Further discussions about how to send a QAPI event to inform about the
hotunplug timeout [2] exposed problems that weren't predicted back when
the idea was developed. Other QEMU machines don't have any type of
hotunplug timeout mechanism for any device, e.g. ACPI based machines
have a way to make hotunplug errors visible to the hypervisor. This
would make this timeout mechanism exclusive to pSeries, which is not
ideal.
The real problem is that a QAPI event that reports hotunplug timeouts
puts the management layer (namely Libvirt) in a weird spot. We're not
telling that the hotunplug failed, because we can't be 100% sure of
that, and yet we're resetting the unplug state back, preventing any
DEVICE_DEL events to reach out in case the guest decides to release the
device. Libvirt would need to inspect the guest itself to see if the
device was released or not, otherwise the internal domain states will be
inconsistent. Moreover, Libvirt already has an 'unplug timeout'
concept, and a QEMU side timeout would need to be juggled together with
the existing Libvirt timeout.
All this considered, this solution ended up creating more trouble than
it solved. This patch reverts the 3 commits that introduced the timeout
mechanism for CPU hotplugs in pSeries machines.
This reverts commit 4515a5f786
"qemu_timer.c: add timer_deadline_ms() helper"
This reverts commit d1c2e3ce3d
"spapr_drc.c: add hotunplug timeout for CPUs"
This reverts commit 51254ffb32
"spapr_drc.c: introduce unplug_timeout_timer"
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1911414
[2] https://lists.gnu.org/archive/html/qemu-devel/2021-03/msg04682.html
CC: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210401000437.131140-2-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There is no H_REGISTER_PROCESS_TABLE, it is H_REGISTER_PROC_TBL handler
for which is still called h_register_process_table() though.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20210225032335.64245-1-aik@ozlabs.ru>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Next batch of patches for the ppc target and machine types. Includes:
* Several cleanups for sm501 from Peter Maydell
* An update to the SLOF guest firmware
* Improved handling of hotplug failures in spapr, associated cleanups
to the hotplug handling code
* Several etsec fixes and cleanups from Bin Meng
* Assorted other fixes and cleanups
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Merge remote-tracking branch 'remotes/dg-gitlab/tags/ppc-for-6.0-20210310' into staging
ppc patch queue for 2021-03-10
Next batch of patches for the ppc target and machine types. Includes:
* Several cleanups for sm501 from Peter Maydell
* An update to the SLOF guest firmware
* Improved handling of hotplug failures in spapr, associated cleanups
to the hotplug handling code
* Several etsec fixes and cleanups from Bin Meng
* Assorted other fixes and cleanups
# gpg: Signature made Wed 10 Mar 2021 04:08:53 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/dg-gitlab/tags/ppc-for-6.0-20210310:
spapr.c: send QAPI event when memory hotunplug fails
spapr.c: remove duplicated assert in spapr_memory_unplug_request()
target/ppc: fix icount support on Book-e vms accessing SPRs
qemu_timer.c: add timer_deadline_ms() helper
spapr_pci.c: add 'unplug already in progress' message for PCI unplug
spapr.c: add 'unplug already in progress' message for PHB unplug
hw/ppc: e500: Add missing <ranges> in the eTSEC node
hw/net: fsl_etsec: Fix build error when HEX_DUMP is on
spapr_drc.c: use DRC reconfiguration to cleanup DIMM unplug state
spapr_drc.c: add hotunplug timeout for CPUs
spapr_drc.c: introduce unplug_timeout_timer
target/ppc: Fix bcdsub. emulation when result overflows
docs/system: Extend PPC section
spapr: rename spapr_drc_detach() to spapr_drc_unplug_request()
spapr_drc.c: use spapr_drc_release() in isolate_physical/set_unusable
pseries: Update SLOF firmware image
spapr_drc.c: do not call spapr_drc_detach() in drc_isolate_logical()
hw/display/sm501: Inline template header into C file
hw/display/sm501: Expand out macros in template header
hw/display/sm501: Remove dead code for non-32-bit RGB surfaces
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Recent changes allowed the pSeries machine to rollback the hotunplug
process for the DIMM when the guest kernel signals, via a
reconfiguration of the DR connector, that it's not going to release the
LMBs.
Let's also warn QAPI listerners about it. One place to do it would be
right after the unplug state is cleaned up,
spapr_clear_pending_dimm_unplug_state(). This would mean that the
function is now doing more than cleaning up the pending dimm state
though.
This patch does the following changes in spapr.c:
- send a QAPI event to inform that we experienced a failure in the
hotunplug of the DIMM;
- rename spapr_clear_pending_dimm_unplug_state() to
spapr_memory_unplug_rollback(). This is a better fit for what the
function is now doing, and it makes callers care more about what the
function goal is and less about spapr.c internals such as clearing
the pending dimm unplug state.
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210302141019.153729-3-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Handling errors in memory hotunplug in the pSeries machine is more
complex than any other device type, because there are all the
complications that other devices has, and more.
For instance, determining a timeout for a DIMM hotunplug must consider
if it's a Hash-MMU or a Radix-MMU guest, because Hash guests takes
longer to hotunplug DIMMs. The size of the DIMM is also a factor, given
that longer DIMMs naturally takes longer to be hotunplugged from the
kernel. And there's also the guest memory usage to be considered: if
there's a process that is consuming memory that would be lost by the
DIMM unplug, the kernel will postpone the unplug process until the
process finishes, and then initiate the regular hotunplug process. The
first two considerations are manageable, but the last one is a deal
breaker.
There is no sane way for the pSeries machine to determine the memory
load in the guest when attempting a DIMM hotunplug - and even if there
was a way, the guest can start using all the RAM in the middle of the
unplug process and invalidate our previous assumptions - and in result
we can't even begin to calculate a timeout for the operation. This means
that we can't implement a viable timeout mechanism for memory unplug in
pSeries.
Going back to why we would consider an unplug timeout, the reason is
that we can't know if the kernel is giving up the unplug. Turns out
that, sometimes, we can. Consider a failed memory hotunplug attempt
where the kernel will error out with the following message:
'pseries-hotplug-mem: Memory indexed-count-remove failed, adding any
removed LMBs'
This happens when there is a LMB that the kernel gave up in removing,
and the LMBs previously marked for removal are now being added back.
This happens in the pseries kernel in [1], dlpar_memory_remove_by_ic()
into dlpar_add_lmb(), and after that update_lmb_associativity_index().
In this function, the kernel is configuring the LMB DRC connector again.
Note that this is a valid usage in LOPAR, as stated in section
"ibm,configure-connector RTAS Call":
'A subsequent sequence of calls to ibm,configure-connector with the same
entry from the “ibm,drc-indexes” or “ibm,drc-info” property will restart
the configuration of devices which were not completely configured.'
We can use this kernel behavior in our favor. If a DRC connector
reconfiguration for a LMB that we marked as unplug pending happens, this
indicates that the kernel changed its mind about the unplug and is
reasserting that it will keep using all the LMBs of the DIMM. In this
case, it's safe to assume that the whole DIMM device unplug was
cancelled.
This patch hops into rtas_ibm_configure_connector() and, in the scenario
described above, clear the unplug state for the DIMM device. This will
not solve all the problems we still have with memory unplug, but it will
cover this case where the kernel reconfigures LMBs after a failed
unplug. We are a bit more resilient, without using an unreliable
timeout, and we didn't make the remaining error cases any worse.
[1] arch/powerpc/platforms/pseries/hotplug-memory.c
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210222194531.62717-6-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There is a reliable way to make a CPU hotunplug fail in the pseries
machine. Hotplug a CPU A, then offline all other CPUs inside the guest
but A. When trying to hotunplug A the guest kernel will refuse to do it,
because A is now the last online CPU of the guest. PAPR has no 'error
callback' in this situation to report back to the platform, so the guest
kernel will deny the unplug in silent and QEMU will never know what
happened. The unplug pending state of A will remain until the guest is
shutdown or rebooted.
Previous attempts of fixing it (see [1] and [2]) were aimed at trying to
mitigate the effects of the problem. In [1] we were trying to guess
which guest CPUs were online to forbid hotunplug of the last online CPU
in the QEMU layer, avoiding the scenario described above because QEMU is
now failing in behalf of the guest. This is not robust because the last
online CPU of the guest can change while we're in the middle of the
unplug process, and our initial assumptions are now invalid. In [2] we
were accepting that our unplug process is uncertain and the user should
be allowed to spam the IRQ hotunplug queue of the guest in case the CPU
hotunplug fails.
This patch presents another alternative, using the timeout
infrastructure introduced in the previous patch. CPU hotunplugs in the
pSeries machine will now timeout after 15 seconds. This is a long time
for a single CPU unplug to occur, regardless of guest load - although
the user is *strongly* encouraged to *not* hotunplug devices from a
guest under high load - and we can be sure that something went wrong if
it takes longer than that for the guest to release the CPU (the same
can't be said about memory hotunplug - more on that in the next patch).
Timing out the unplug operation will reset the unplug state of the CPU
and allow the user to try it again, regardless of the error situation
that prevented the hotunplug to occur. Of all the not so pretty
fixes/mitigations for CPU hotunplug errors in pSeries, timing out the
operation is an admission that we have no control in the process, and
must assume the worst case if the operation doesn't succeed in a
sensible time frame.
[1] https://lists.gnu.org/archive/html/qemu-devel/2021-01/msg03353.html
[2] https://lists.gnu.org/archive/html/qemu-devel/2021-01/msg04400.html
Reported-by: Xujun Ma <xuma@redhat.com>
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1911414
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210222194531.62717-5-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The LoPAR spec provides no way for the guest kernel to report failure of
hotplug/hotunplug events. This wouldn't be bad if those operations were
granted to always succeed, but that's far for the reality.
What ends up happening is that, in the case of a failed hotunplug,
regardless of whether it was a QEMU error or a guest misbehavior, the
pSeries machine is retaining the unplug state of the device in the
running guest. This state is cleanup in machine reset, where it is
assumed that this state represents a device that is pending unplug, and
the device is hotunpluged from the board. Until the reset occurs, any
hotunplug operation of the same device is forbid because there is a
pending unplug state.
This behavior has at least one undesirable side effect. A long standing
pending unplug state is, more often than not, the result of a hotunplug
error. The user had to dealt with it, since retrying to unplug the
device is noy allowed, and then in the machine reset we're removing the
device from the guest. This means that we're failing the user twice -
failed to hotunplug when asked, then hotunplugged without notice.
Solutions to this problem range between trying to predict when the
hotunplug will fail and forbid the operation from the QEMU layer, from
opening up the IRQ queue to allow for multiple hotunplug attempts, from
telling the users to 'reboot the machine if something goes wrong'. The
first solution is flawed because we can't fully predict guest behavior
from QEMU, the second solution is a trial and error remediation that
counts on a hope that the unplug will eventually succeed, and the third
is ... well.
This patch introduces a crude, but effective solution to hotunplug
errors in the pSeries machine. For each unplug done, we'll timeout after
some time. If a certain amount of time passes, we'll cleanup the
hotunplug state from the machine. During the timeout period, any unplug
operations in the same device will still be blocked. After that, we'll
assume that the guest failed the operation, and allow the user to try
again. If the timeout is too short we'll prevent legitimate hotunplug
situations to occur, so we'll need to overestimate the regular time an
unplug operation takes to succeed to account that.
The true solution for the hotunplug errors in the pSeries machines is a
PAPR change to allow for the guest to warn the platform about it. For
now, the work done in this timeout design can be used for the new PAPR
'abort hcall' in the future, given that for both cases we'll need code
to cleanup the existing unplug states of the DRCs.
At this moment we're adding the basic wiring of the timer into the DRC.
Next patch will use the timer to timeout failed CPU hotunplugs.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210222194531.62717-4-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
spapr_drc_detach() is not the best name for what the function does. The
function does not detach the DRC, it makes an uncommited attempt to do
it. It'll mark the DRC as pending unplug, via the 'unplug_request'
flag, and only if the DRC state is drck->empty_state it will detach the
DRC, via spapr_drc_release().
This is a contrast with its pair spapr_drc_attach(), where the function
is indeed creating the DRC QOM object. If you know what
spapr_drc_attach() does, you can be misled into thinking that
spapr_drc_detach() is removing the DRC from QEMU internal state, which
isn't true.
The current role of this function is better described as a request for
detach, since there's no guarantee that we're going to detach the DRC in
the end. Rename the function to spapr_drc_unplug_request to reflect
what is is doing.
The initial idea was to change the name to spapr_drc_detach_request(),
and later on change the unplug_request flag to detach_request. However,
unplug_request is a migratable boolean for a long time now and renaming
it is not worth the trouble. spapr_drc_unplug_request() setting
drc->unplug_request is more natural than spapr_drc_detach_request
setting drc->unplug_request.
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210222194531.62717-3-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
We forward-declare Object typedef in "qemu/typedefs.h" since commit
ca27b5eb7c ("qom/object: Move Object typedef to 'qemu/typedefs.h'").
Use it everywhere to make the code simpler.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210225182003.3629342-1-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
We'll need to check the initial value given to spapr->gpu_numa_id when
building the rtas DT, so put it in a helper for easier access and to
avoid repetition.
Tested-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210128174213.1349181-3-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This function is used only in spapr_numa.c.
Tested-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210128174213.1349181-2-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This to map the PNOR from the machine init handler directly and finish
the cleanup of the LPC model.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20210126171059.307867-8-clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
ENDs allocated by OPAL for the HW thread VPs are tagged as owned by FW.
Dump the state in 'info pic'.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20210126171059.307867-3-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Some upcoming POWER machines have a system called PEF (Protected
Execution Facility) which uses a small ultravisor to allow guests to
run in a way that they can't be eavesdropped by the hypervisor. The
effect is roughly similar to AMD SEV, although the mechanisms are
quite different.
Most of the work of this is done between the guest, KVM and the
ultravisor, with little need for involvement by qemu. However qemu
does need to tell KVM to allow secure VMs.
Because the availability of secure mode is a guest visible difference
which depends on having the right hardware and firmware, we don't
enable this by default. In order to run a secure guest you need to
create a "pef-guest" object and set the confidential-guest-support
property to point to it.
Note that this just *allows* secure guests, the architecture of PEF is
such that the guest still needs to talk to the ultravisor to enter
secure mode. Qemu has no direct way of knowing if the guest is in
secure mode, and certainly can't know until well after machine
creation time.
To start a PEF-capable guest, use the command line options:
-object pef-guest,id=pef0 -machine confidential-guest-support=pef0
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
The function is called only inside spapr_hcall.c.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210114180628.1675603-3-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This whitespace was messing with lots of diffs if you happen
to use an editor that eliminates trailing whitespaces on file
save.
Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20210114180628.1675603-2-danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Since commit 1e8b5b1aa1 ("spapr: Allow memory unplug to always succeed")
trying to unplug memory from a guest that doesn't support it (eg. rhel6)
no longer generates an error like it used to. Instead, it leaves the
memory around : only a subsequent reboot or manual use of drmgr within
the guest can complete the hot-unplug sequence. A flag was added to
SpaprMachineClass so that this new behavior only applies to the default
machine type.
We can do better. CAS processes all pending hot-unplug requests. This
means that we don't really care about what the guest supports if
the hot-unplug request happens before CAS.
All guests that we care for, even old ones, set enough bits in OV5
that lead to a non-empty bitmap in spapr->ov5_cas. Use that as a
heuristic to decide if CAS has already occured or not.
Always accept unplug requests that happen before CAS since CAS will
process them. Restore the previous behavior of rejecting them after
CAS when we know that the guest doesn't support memory hot-unplug.
This behavior is suitable for all machine types : this allows to
drop the pre_6_0_memory_unplug flag.
Fixes: 1e8b5b1aa1 ("spapr: Allow memory unplug to always succeed")
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <161012708715.801107.11418801796987916516.stgit@bahia.lan>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Now we've converted all the callsites to directly create the QOM UIC
device themselves, the ppcuic_init() function is unused and can be
removed. The enum defining PPCUIC symbolic constants can be moved
to the ppc-uic.h header where it more naturally belongs.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Tested-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-Id: <20210108171212.16500-5-peter.maydell@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
No need to expose the way DRCs are traversed outside of spapr_drc.c.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201218103400.689660-4-groug@kaod.org>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Documentation of object_property_iter_init() clearly stipulates that
"it is forbidden to modify the property list while iterating". But this
is exactly what we do when resetting transient DR connectors during CAS.
The call to spapr_drc_reset() can finalize the hot-unplug sequence of a
PHB or a PCI bridge, both of which will then in turn destroy their PCI
DRCs. This could potentially invalidate the iterator. It is pure luck
that this haven't caused any issues so far.
Change spapr_drc_reset() to return true if it caused a device to be
removed. Restart from scratch in this case. This can potentially
increase the overall DRC reset time, especially with a high maxmem
which generates a lot of LMB DRCs. But this kind of setup is rare,
and so is the use case of rebooting a guest while doing hot-unplug.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201218103400.689660-3-groug@kaod.org>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Non-transient DRCs are either in the empty or the ready state,
which means spapr_drc_reset() doesn't change their state. It
is thus not needed to do any checking. Call spapr_drc_reset()
unconditionally and squash spapr_drc_transient() into its
only user, spapr_drc_needed().
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201218103400.689660-2-groug@kaod.org>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Running a guest with 128 NUMA nodes crashes QEMU:
../../util/error.c:59: error_setv: Assertion `*errp == NULL' failed.
The crash happens when setting the FWNMI migration blocker:
2861 if (spapr_get_cap(spapr, SPAPR_CAP_FWNMI) == SPAPR_CAP_ON) {
2862 /* Create the error string for live migration blocker */
2863 error_setg(&spapr->fwnmi_migration_blocker,
2864 "A machine check is being handled during migration. The handler"
2865 "may run and log hardware error on the destination");
2866 }
Inspection reveals that papr->fwnmi_migration_blocker isn't NULL:
(gdb) p spapr->fwnmi_migration_blocker
$1 = (Error *) 0x8000000004000000
Since this is the only place where papr->fwnmi_migration_blocker is
set, this means someone wrote there in our back. Further analysis
points to spapr_numa_associativity_init(), especially the part
that initializes the associative arrays for NVLink GPUs:
max_nodes_with_gpus = nb_numa_nodes + NVGPU_MAX_NUM;
ie. max_nodes_with_gpus = 128 + 6, but the array isn't sized to
accommodate the 6 extra nodes:
struct SpaprMachineState {
.
.
.
uint32_t numa_assoc_array[MAX_NODES][NUMA_ASSOC_SIZE];
Error *fwnmi_migration_blocker;
};
and the following loops happily overwrite spapr->fwnmi_migration_blocker,
and probably more:
for (i = nb_numa_nodes; i < max_nodes_with_gpus; i++) {
spapr->numa_assoc_array[i][0] = cpu_to_be32(MAX_DISTANCE_REF_POINTS);
for (j = 1; j < MAX_DISTANCE_REF_POINTS; j++) {
uint32_t gpu_assoc = smc->pre_5_1_assoc_refpoints ?
SPAPR_GPU_NUMA_ID : cpu_to_be32(i);
spapr->numa_assoc_array[i][j] = gpu_assoc;
}
spapr->numa_assoc_array[i][MAX_DISTANCE_REF_POINTS] = cpu_to_be32(i);
}
Fix the size of the array. This requires "hw/ppc/spapr.h" to see
NVGPU_MAX_NUM. Including "hw/pci-host/spapr.h" introduces a
circular dependency that breaks the build, so this moves the
definition of NVGPU_MAX_NUM to "hw/ppc/spapr.h" instead.
Reported-by: Min Deng <mdeng@redhat.com>
BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1908693
Fixes: dd7e1d7ae4 ("spapr_numa: move NVLink2 associativity handling to spapr_numa.c")
Cc: danielhb413@gmail.com
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160829960428.734871.12634150161215429514.stgit@bahia.lan>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
It is currently impossible to hot-unplug a memory device between
machine reset and CAS.
(qemu) device_del dimm1
Error: Memory hot unplug not supported for this guest
This limitation was introduced in order to provide an explicit
error path for older guests that didn't support hot-plug event
sources (and thus memory hot-unplug).
The linux kernel has been supporting these since 4.11. All recent
enough guests are thus capable of handling the removal of a memory
device at all time, including during early boot.
Lift the limitation for the latest machine type. This means that
trying to unplug memory from a guest that doesn't support it will
likely just do nothing and the memory will only get removed at
next reboot. Such older guests can still get the existing behavior
by using an older machine type.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160794035064.23292.17560963281911312439.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This allows to drop a user of qdev_get_machine().
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201209170052.1431440-4-groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
All users are passing &error_abort already. Document the fact
that spapr_drc_attach() should only be passed a free DRC, which
is supposedly the case if appropriate checking is done earlier.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201201113728.885700-5-groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Read documentation in "qapi/error.h" and changelog of commit
e3fe3988d7 ("error: Document Error API usage rules") for
rationale.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201120234208.683521-7-groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Pre-plug of a memory device, be it an NVDIMM or a PC-DIMM, ensures
that the memory slot is available and that addresses don't overlap
with existing memory regions. The corresponding DRCs in the LMB
and PMEM namespaces are thus necessarily attachable at plug time.
Pass &error_abort to spapr_drc_attach() in spapr_add_lmbs() and
spapr_add_nvdimm(). This allows to greatly simplify error handling
on the plug path.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201120234208.683521-3-groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Never used from the start.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20201120174646.619395-6-groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.
This patch contains all the files, whose maintainer I could not get
from ‘get_maintainer.pl’ script.
Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Message-Id: <20201023124424.20177-1-chetan4windows@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
[thuth: Adapted exec.c and qdev-monitor.c to new location]
Signed-off-by: Thomas Huth <thuth@redhat.com>
There is no "version 2" of the "Lesser" General Public License.
It is either "GPL version 2.0" or "Lesser GPL version 2.1".
This patch replaces all occurrences of "Lesser GPL version 2" with
"Lesser GPL version 2.1" in comment section.
Signed-off-by: Chetan Pant <chetan4windows@gmail.com>
Message-Id: <20201016145346.27167-1-chetan4windows@gmail.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
spapr_reallocate_hpt() has three users, two of which pass &error_fatal
and the third one, htab_load(), passes &local_err, uses it to detect
failures and simply propagates -EINVAL up to vmstate_load(), which will
cause QEMU to exit. It is thus confusing that spapr_reallocate_hpt()
doesn't return right away when an error is detected in some cases. Also,
the comment suggesting that the caller is welcome to try to carry on
seems like a remnant in this respect.
This can be improved:
- change spapr_reallocate_hpt() to always report a negative errno on
failure, either as reported by KVM or -ENOSPC if the HPT is smaller
than what was asked,
- use that to detect failures in htab_load() which is preferred over
checking &local_err,
- propagate this negative errno to vmstate_load() because it is more
accurate than propagating -EINVAL for all possible errors.
[dwg: Fix compile error due to omitted prelim patch]
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160371605460.305923.5890143959901241157.stgit@bahia.lan>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
As recommended in "qapi/error.h", add a bool return value to
spapr_add_lmbs() and spapr_add_nvdimm(), and use them instead
of local_err in spapr_memory_plug().
This allows to get rid of the error propagation overhead.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <160309734178.2739814.3488437759887793902.stgit@bahia.lan>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
