| Age | Commit message (Collapse) | Author |
|---|
|
We have a fix to apply on top of commit 96d4f267e40f ("Remove 'type'
argument from access_ok() function"), so merge master to get it.
|
|
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
|
Old GCCs (4.6.3 at least), aren't able to follow the logic in
__kvmhv_copy_tofrom_guest_radix() and warn that old_pid is used
uninitialized:
arch/powerpc/kvm/book3s_64_mmu_radix.c:75:3: error: 'old_pid' may be
used uninitialized in this function
The logic is OK, we only use old_pid if quadrant == 1, and in that
case it has definitely be initialised, eg:
if (quadrant == 1) {
old_pid = mfspr(SPRN_PID);
...
if (quadrant == 1 && pid != old_pid)
mtspr(SPRN_PID, old_pid);
Annotate it to fix the error.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kconfig updates from Masahiro Yamada:
- support -y option for merge_config.sh to avoid downgrading =y to =m
- remove S_OTHER symbol type, and touch include/config/*.h files correctly
- fix file name and line number in lexer warnings
- fix memory leak when EOF is encountered in quotation
- resolve all shift/reduce conflicts of the parser
- warn no new line at end of file
- make 'source' statement more strict to take only string literal
- rewrite the lexer and remove the keyword lookup table
- convert to SPDX License Identifier
- compile C files independently instead of including them from zconf.y
- fix various warnings of gconfig
- misc cleanups
* tag 'kconfig-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
kconfig: surround dbg_sym_flags with #ifdef DEBUG to fix gconf warning
kconfig: split images.c out of qconf.cc/gconf.c to fix gconf warnings
kconfig: add static qualifiers to fix gconf warnings
kconfig: split the lexer out of zconf.y
kconfig: split some C files out of zconf.y
kconfig: convert to SPDX License Identifier
kconfig: remove keyword lookup table entirely
kconfig: update current_pos in the second lexer
kconfig: switch to ASSIGN_VAL state in the second lexer
kconfig: stop associating kconf_id with yylval
kconfig: refactor end token rules
kconfig: stop supporting '.' and '/' in unquoted words
treewide: surround Kconfig file paths with double quotes
microblaze: surround string default in Kconfig with double quotes
kconfig: use T_WORD instead of T_VARIABLE for variables
kconfig: use specific tokens instead of T_ASSIGN for assignments
kconfig: refactor scanning and parsing "option" properties
kconfig: use distinct tokens for type and default properties
kconfig: remove redundant token defines
kconfig: rename depends_list to comment_option_list
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- Mitigations for Spectre v2 on some Freescale (NXP) CPUs.
- A large series adding support for pass-through of Nvidia V100 GPUs
to guests on Power9.
- Another large series to enable hardware assistance for TLB table
walk on MPC8xx CPUs.
- Some preparatory changes to our DMA code, to make way for further
cleanups from Christoph.
- Several fixes for our Transactional Memory handling discovered by
fuzzing the signal return path.
- Support for generating our system call table(s) from a text file
like other architectures.
- A fix to our page fault handler so that instead of generating a
WARN_ON_ONCE, user accesses of kernel addresses instead print a
ratelimited and appropriately scary warning.
- A cosmetic change to make our unhandled page fault messages more
similar to other arches and also more compact and informative.
- Freescale updates from Scott:
"Highlights include elimination of legacy clock bindings use from
dts files, an 83xx watchdog handler, fixes to old dts interrupt
errors, and some minor cleanup."
And many clean-ups, reworks and minor fixes etc.
Thanks to: Alexandre Belloni, Alexey Kardashevskiy, Andrew Donnellan,
Aneesh Kumar K.V, Arnd Bergmann, Benjamin Herrenschmidt, Breno Leitao,
Christian Lamparter, Christophe Leroy, Christoph Hellwig, Daniel
Axtens, Darren Stevens, David Gibson, Diana Craciun, Dmitry V. Levin,
Firoz Khan, Geert Uytterhoeven, Greg Kurz, Gustavo Romero, Hari
Bathini, Joel Stanley, Kees Cook, Madhavan Srinivasan, Mahesh
Salgaonkar, Markus Elfring, Mathieu Malaterre, Michal Suchánek, Naveen
N. Rao, Nick Desaulniers, Oliver O'Halloran, Paul Mackerras, Ram Pai,
Ravi Bangoria, Rob Herring, Russell Currey, Sabyasachi Gupta, Sam
Bobroff, Satheesh Rajendran, Scott Wood, Segher Boessenkool, Stephen
Rothwell, Tang Yuantian, Thiago Jung Bauermann, Yangtao Li, Yuantian
Tang, Yue Haibing"
* tag 'powerpc-4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (201 commits)
Revert "powerpc/fsl_pci: simplify fsl_pci_dma_set_mask"
powerpc/zImage: Also check for stdout-path
powerpc: Fix HMIs on big-endian with CONFIG_RELOCATABLE=y
macintosh: Use of_node_name_{eq, prefix} for node name comparisons
ide: Use of_node_name_eq for node name comparisons
powerpc: Use of_node_name_eq for node name comparisons
powerpc/pseries/pmem: Convert to %pOFn instead of device_node.name
powerpc/mm: Remove very old comment in hash-4k.h
powerpc/pseries: Fix node leak in update_lmb_associativity_index()
powerpc/configs/85xx: Enable CONFIG_DEBUG_KERNEL
powerpc/dts/fsl: Fix dtc-flagged interrupt errors
clk: qoriq: add more compatibles strings
powerpc/fsl: Use new clockgen binding
powerpc/83xx: handle machine check caused by watchdog timer
powerpc/fsl-rio: fix spelling mistake "reserverd" -> "reserved"
powerpc/fsl_pci: simplify fsl_pci_dma_set_mask
arch/powerpc/fsl_rmu: Use dma_zalloc_coherent
vfio_pci: Add NVIDIA GV100GL [Tesla V100 SXM2] subdriver
vfio_pci: Allow regions to add own capabilities
vfio_pci: Allow mapping extra regions
...
|
|
The Kconfig lexer supports special characters such as '.' and '/' in
the parameter context. In my understanding, the reason is just to
support bare file paths in the source statement.
I do not see a good reason to complicate Kconfig for the room of
ambiguity.
The majority of code already surrounds file paths with double quotes,
and it makes sense since file paths are constant string literals.
Make it treewide consistent now.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into kvm-next
Second PPC KVM update for 4.21
This has 5 commits that fix page dirty tracking when running nested
HV KVM guests, from Suraj Jitindar Singh.
|
|
The patch is to make kvm_set_spte_hva() return int and caller can
check return value to determine flush tlb or not.
Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
This new memory does not have page structs as it is not plugged to
the host so gup() will fail anyway.
This adds 2 helpers:
- mm_iommu_newdev() to preregister the "memory device" memory so
the rest of API can still be used;
- mm_iommu_is_devmem() to know if the physical address is one of thise
new regions which we must avoid unpinning of.
This adds @mm to tce_page_is_contained() and iommu_tce_xchg() to test
if the memory is device memory to avoid pfn_to_page().
This adds a check for device memory in mm_iommu_ua_mark_dirty_rm() which
does delayed pages dirtying.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
The rc bits contained in ptes are used to track whether a page has been
accessed and whether it is dirty. The accessed bit is used to age a page
and the dirty bit to track whether a page is dirty or not.
Now that we support nested guests there are three ptes which track the
state of the same page:
- The partition-scoped page table in the L1 guest, mapping L2->L1 address
- The partition-scoped page table in the host for the L1 guest, mapping
L1->L0 address
- The shadow partition-scoped page table for the nested guest in the host,
mapping L2->L0 address
The idea is to attempt to keep the rc state of these three ptes in sync,
both when setting and when clearing rc bits.
When setting the bits we achieve consistency by:
- Initially setting the bits in the shadow page table as the 'and' of the
other two.
- When updating in software the rc bits in the shadow page table we
ensure the state is consistent with the other two locations first, and
update these before reflecting the change into the shadow page table.
i.e. only set the bits in the L2->L0 pte if also set in both the
L2->L1 and the L1->L0 pte.
When clearing the bits we achieve consistency by:
- The rc bits in the shadow page table are only cleared when discarding
a pte, and we don't need to record this as if either bit is set then
it must also be set in the pte mapping L1->L0.
- When L1 clears an rc bit in the L2->L1 mapping it __should__ issue a
tlbie instruction
- This means we will discard the pte from the shadow page table
meaning the mapping will have to be setup again.
- When setup the pte again in the shadow page table we will ensure
consistency with the L2->L1 pte.
- When the host clears an rc bit in the L1->L0 mapping we need to also
clear the bit in any ptes in the shadow page table which map the same
gfn so we will be notified if a nested guest accesses the page.
This case is what this patch specifically concerns.
- We can search the nest_rmap list for that given gfn and clear the
same bit from all corresponding ptes in shadow page tables.
- If a nested guest causes either of the rc bits to be set by software
in future then we will update the L1->L0 pte and maintain consistency.
With the process outlined above we aim to maintain consistency of the 3
pte locations where we track rc for a given guest page.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Introduce a function kvmhv_update_nest_rmap_rc_list() which for a given
nest_rmap list will traverse it, find the corresponding pte in the shadow
page tables, and if it still maps the same host page update the rc bits
accordingly.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
The shadow page table contains ptes for translations from nested guest
address to host address. Currently when creating these ptes we take the
rc bits from the pte for the L1 guest address to host address
translation. This is incorrect as we must also factor in the rc bits
from the pte for the nested guest address to L1 guest address
translation (as contained in the L1 guest partition table for the nested
guest).
By not calculating these bits correctly L1 may not have been correctly
notified when it needed to update its rc bits in the partition table it
maintains for its nested guest.
Modify the code so that the rc bits in the resultant pte for the L2->L0
translation are the 'and' of the rc bits in the L2->L1 pte and the L1->L0
pte, also accounting for whether this was a write access when setting
the dirty bit.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Nested rmap entries are used to store the translation from L1 gpa to L2
gpa when entries are inserted into the shadow (nested) page tables. This
rmap list is located by indexing the rmap array in the memslot by L1
gfn. When we come to search for these entries we only know the L1 page size
(which could be PAGE_SIZE, 2M or a 1G page) and so can only select a gfn
aligned to that size. This means that when we insert the entry, so we can
find it later, we need to align the gfn we use to select the rmap list
in which to insert the entry to L1 page size as well.
By not doing this we were missing nested rmap entries when modifying L1
ptes which were for a page also passed through to an L2 guest.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
We already hold the kvm->mmu_lock spin lock across updating the rc bits
in the pte for the L1 guest. Continue to hold the lock across updating
the rc bits in the pte for the nested guest as well to prevent
invalidations from occurring.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
PPC KVM update for 4.21 from Paul Mackerras
The main new feature this time is support in HV nested KVM for passing
a device that is emulated by a level 0 hypervisor and presented to
level 1 as a PCI device through to a level 2 guest using VFIO.
Apart from that there are improvements for migration of radix guests
under HV KVM and some other fixes and cleanups.
|
|
Switching from the guest to host is another place
where the speculative accesses can be exploited.
Flush the branch predictor when entering KVM.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
In order to flush the branch predictor the guest kernel performs
writes to the BUCSR register which is hypervisor privilleged. However,
the branch predictor is flushed at each KVM entry, so the branch
predictor has been already flushed, so just return as soon as possible
to guest.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com>
[mpe: Tweak comment formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Previously when a device was being emulated by an L1 guest for an L2
guest, that device couldn't then be passed through to an L3 guest. This
was because the L1 guest had no method for accessing L3 memory.
The hcall H_COPY_TOFROM_GUEST provides this access. Thus this setup for
passthrough can now be allowed.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
quadrants 1 & 2
A guest cannot access quadrants 1 or 2 as this would result in an
exception. Thus introduce the hcall H_COPY_TOFROM_GUEST to be used by a
guest when it wants to perform an access to quadrants 1 or 2, for
example when it wants to access memory for one of its nested guests.
Also provide an implementation for the kvm-hv module.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Allow for a device which is being emulated at L0 (the host) for an L1
guest to be passed through to a nested (L2) guest.
The existing kvmppc_hv_emulate_mmio function can be used here. The main
challenge is that for a load the result must be stored into the L2 gpr,
not an L1 gpr as would normally be the case after going out to qemu to
complete the operation. This presents a challenge as at this point the
L2 gpr state has been written back into L1 memory.
To work around this we store the address in L1 memory of the L2 gpr
where the result of the load is to be stored and use the new io_gpr
value KVM_MMIO_REG_NESTED_GPR to indicate that this is a nested load for
which completion must be done when returning back into the kernel. Then
in kvmppc_complete_mmio_load() the resultant value is written into L1
memory at the location of the indicated L2 gpr.
Note that we don't currently let an L1 guest emulate a device for an L2
guest which is then passed through to an L3 guest.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
The functions kvmppc_st and kvmppc_ld are used to access guest memory
from the host using a guest effective address. They do so by translating
through the process table to obtain a guest real address and then using
kvm_read_guest or kvm_write_guest to make the access with the guest real
address.
This method of access however only works for L1 guests and will give the
incorrect results for a nested guest.
We can however use the store_to_eaddr and load_from_eaddr kvmppc_ops to
perform the access for a nested guesti (and a L1 guest). So attempt this
method first and fall back to the old method if this fails and we aren't
running a nested guest.
At this stage there is no fall back method to perform the access for a
nested guest and this is left as a future improvement. For now we will
return to the nested guest and rely on the fact that a translation
should be faulted in before retrying the access.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
The kvmppc_ops struct is used to store function pointers to kvm
implementation specific functions.
Introduce two new functions load_from_eaddr and store_to_eaddr to be
used to load from and store to a guest effective address respectively.
Also implement these for the kvm-hv module. If we are using the radix
mmu then we can call the functions to access quadrant 1 and 2.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
The POWER9 radix mmu has the concept of quadrants. The quadrant number
is the two high bits of the effective address and determines the fully
qualified address to be used for the translation. The fully qualified
address consists of the effective lpid, the effective pid and the
effective address. This gives then 4 possible quadrants 0, 1, 2, and 3.
When accessing these quadrants the fully qualified address is obtained
as follows:
Quadrant | Hypervisor | Guest
--------------------------------------------------------------------------
| EA[0:1] = 0b00 | EA[0:1] = 0b00
0 | effLPID = 0 | effLPID = LPIDR
| effPID = PIDR | effPID = PIDR
--------------------------------------------------------------------------
| EA[0:1] = 0b01 |
1 | effLPID = LPIDR | Invalid Access
| effPID = PIDR |
--------------------------------------------------------------------------
| EA[0:1] = 0b10 |
2 | effLPID = LPIDR | Invalid Access
| effPID = 0 |
--------------------------------------------------------------------------
| EA[0:1] = 0b11 | EA[0:1] = 0b11
3 | effLPID = 0 | effLPID = LPIDR
| effPID = 0 | effPID = 0
--------------------------------------------------------------------------
In the Guest;
Quadrant 3 is normally used to address the operating system since this
uses effPID=0 and effLPID=LPIDR, meaning the PID register doesn't need to
be switched.
Quadrant 0 is normally used to address user space since the effLPID and
effPID are taken from the corresponding registers.
In the Host;
Quadrant 0 and 3 are used as above, however the effLPID is always 0 to
address the host.
Quadrants 1 and 2 can be used by the host to address guest memory using
a guest effective address. Since the effLPID comes from the LPID register,
the host loads the LPID of the guest it would like to access (and the
PID of the process) and can perform accesses to a guest effective
address.
This means quadrant 1 can be used to address the guest user space and
quadrant 2 can be used to address the guest operating system from the
hypervisor, using a guest effective address.
Access to the quadrants can cause a Hypervisor Data Storage Interrupt
(HDSI) due to being unable to perform partition scoped translation.
Previously this could only be generated from a guest and so the code
path expects us to take the KVM trampoline in the interrupt handler.
This is no longer the case so we modify the handler to call
bad_page_fault() to check if we were expecting this fault so we can
handle it gracefully and just return with an error code. In the hash mmu
case we still raise an unknown exception since quadrants aren't defined
for the hash mmu.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
There exists a function kvm_is_radix() which is used to determine if a
kvm instance is using the radix mmu. However this only applies to the
first level (L1) guest. Add a function kvmhv_vcpu_is_radix() which can
be used to determine if the current execution context of the vcpu is
radix, accounting for if the vcpu is running a nested guest.
Currently all nested guests must be radix but this may change in the
future.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
The kvm capability KVM_CAP_SPAPR_TCE_VFIO is used to indicate the
availability of in kernel tce acceleration for vfio. However it is
currently the case that this is only available on a powernv machine,
not for a pseries machine.
Thus make this capability dependent on having the cpu feature
CPU_FTR_HVMODE.
[paulus@ozlabs.org - fixed compilation for Book E.]
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This adds code to flush the partition-scoped page tables for a radix
guest when dirty tracking is turned on or off for a memslot. Only the
guest real addresses covered by the memslot are flushed. The reason
for this is to get rid of any 2M PTEs in the partition-scoped page
tables that correspond to host transparent huge pages, so that page
dirtiness is tracked at a system page (4k or 64k) granularity rather
than a 2M granularity. The page tables are also flushed when turning
dirty tracking off so that the memslot's address space can be
repopulated with THPs if possible.
To do this, we add a new function kvmppc_radix_flush_memslot(). Since
this does what's needed for kvmppc_core_flush_memslot_hv() on a radix
guest, we now make kvmppc_core_flush_memslot_hv() call the new
kvmppc_radix_flush_memslot() rather than calling kvm_unmap_radix()
for each page in the memslot. This has the effect of fixing a bug in
that kvmppc_core_flush_memslot_hv() was previously calling
kvm_unmap_radix() without holding the kvm->mmu_lock spinlock, which
is required to be held.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This adds 'const' to the declarations for the struct kvm_memory_slot
pointer parameters of some functions, which will make it possible to
call those functions from kvmppc_core_commit_memory_region_hv()
in the next patch.
This also fixes some comments about locking.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
For radix guests, this makes KVM map guest memory as individual pages
when dirty page logging is enabled for the memslot corresponding to the
guest real address. Having a separate partition-scoped PTE for each
system page mapped to the guest means that we have a separate dirty
bit for each page, thus making the reported dirty bitmap more accurate.
Without this, if part of guest memory is backed by transparent huge
pages, the dirty status is reported at a 2MB granularity rather than
a 64kB (or 4kB) granularity for that part, causing userspace to have
to transmit more data when migrating the guest.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Currently, kvm_arch_commit_memory_region() gets called with a
parameter indicating what type of change is being made to the memslot,
but it doesn't pass it down to the platform-specific memslot commit
functions. This adds the `change' parameter to the lower-level
functions so that they can use it in future.
[paulus@ozlabs.org - fix book E also.]
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
The first such capability to be handled in virt/kvm/ will be manual
dirty page reprotection.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
|
|
When booting a kvm-pr guest on a POWER9 machine the following message is
observed:
"qemu-system-ppc64: KVM does not support 1TiB segments which guest expects"
This is because the guest is expecting to be able to use 1T segments
however we don't indicate support for it. This is because we don't set
the BOOK3S_HFLAG_MULTI_PGSIZE flag in the hflags in kvmppc_set_pvr_pr()
on POWER9.
POWER9 does indeed have support for 1T segments, so add a case for
POWER9 to the switch statement to ensure it is set.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Testing has revealed an occasional crash which appears to be caused
by a race between kvmppc_switch_mmu_to_hpt and kvm_unmap_hva_range_hv.
The symptom is a NULL pointer dereference in __find_linux_pte() called
from kvm_unmap_radix() with kvm->arch.pgtable == NULL.
Looking at kvmppc_switch_mmu_to_hpt(), it does indeed clear
kvm->arch.pgtable (via kvmppc_free_radix()) before setting
kvm->arch.radix to NULL, and there is nothing to prevent
kvm_unmap_hva_range_hv() or the other MMU callback functions from
being called concurrently with kvmppc_switch_mmu_to_hpt() or
kvmppc_switch_mmu_to_radix().
This patch therefore adds calls to spin_lock/unlock on the kvm->mmu_lock
around the assignments to kvm->arch.radix, and makes sure that the
partition-scoped radix tree or HPT is only freed after changing
kvm->arch.radix.
This also takes the kvm->mmu_lock in kvmppc_rmap_reset() to make sure
that the clearing of each rmap array (one per memslot) doesn't happen
concurrently with use of the array in the kvm_unmap_hva_range_hv()
or the other MMU callbacks.
Fixes: 18c3640cefc7 ("KVM: PPC: Book3S HV: Add infrastructure for running HPT guests on radix host")
Cc: stable@vger.kernel.org # v4.15+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
The purpose of this patch is to move platform specific
mmu-xxx.h files in platform directories like pte-xxx.h files.
In the meantime this patch creates common nohash and
nohash/32 + nohash/64 mmu.h files for future common parts.
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
https://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD
PPC KVM fixes for 4.20
This has a single 1-line patch which fixes a bug in the recently-merged
nested HV KVM support.
|
|
While running a nested guest VCPU on L0 via H_ENTER_NESTED hcall, a
pending signal in the L0 QEMU process can generate the following
sequence:
ret0 = kvmppc_pseries_do_hcall()
ret1 = kvmhv_enter_nested_guest()
ret2 = kvmhv_run_single_vcpu()
if (ret2 == -EINTR)
return H_INTERRUPT
if (ret1 == H_INTERRUPT)
kvmppc_set_gpr(vcpu, 3, 0)
return -EINTR
/* skipped: */
kvmppc_set_gpr(vcpu, 3, ret)
vcpu->arch.hcall_needed = 0
return RESUME_GUEST
which causes an exit to L0 userspace with ret0 == -EINTR.
The intention seems to be to set the hcall return value to 0 (via
VCPU r3) so that L1 will see a successful return from H_ENTER_NESTED
once we resume executing the VCPU. However, because we don't set
vcpu->arch.hcall_needed = 0, we do the following once userspace
resumes execution via kvm_arch_vcpu_ioctl_run():
...
} else if (vcpu->arch.hcall_needed) {
int i
kvmppc_set_gpr(vcpu, 3, run->papr_hcall.ret);
for (i = 0; i < 9; ++i)
kvmppc_set_gpr(vcpu, 4 + i, run->papr_hcall.args[i]);
vcpu->arch.hcall_needed = 0;
since vcpu->arch.hcall_needed == 1 indicates that userspace should
have handled the hcall and stored the return value in
run->papr_hcall.ret. Since that's not the case here, we can get an
unexpected value in VCPU r3, which can result in
kvmhv_p9_guest_entry() reporting an unexpected trap value when it
returns from H_ENTER_NESTED, causing the following register dump to
console via subsequent call to kvmppc_handle_exit_hv() in L1:
[ 350.612854] vcpu 00000000f9564cf8 (0):
[ 350.612915] pc = c00000000013eb98 msr = 8000000000009033 trap = 1
[ 350.613020] r 0 = c0000000004b9044 r16 = 0000000000000000
[ 350.613075] r 1 = c00000007cffba30 r17 = 0000000000000000
[ 350.613120] r 2 = c00000000178c100 r18 = 00007fffc24f3b50
[ 350.613166] r 3 = c00000007ef52480 r19 = 00007fffc24fff58
[ 350.613212] r 4 = 0000000000000000 r20 = 00000a1e96ece9d0
[ 350.613253] r 5 = 70616d00746f6f72 r21 = 00000a1ea117c9b0
[ 350.613295] r 6 = 0000000000000020 r22 = 00000a1ea1184360
[ 350.613338] r 7 = c0000000783be440 r23 = 0000000000000003
[ 350.613380] r 8 = fffffffffffffffc r24 = 00000a1e96e9e124
[ 350.613423] r 9 = c00000007ef52490 r25 = 00000000000007ff
[ 350.613469] r10 = 0000000000000004 r26 = c00000007eb2f7a0
[ 350.613513] r11 = b0616d0009eccdb2 r27 = c00000007cffbb10
[ 350.613556] r12 = c0000000004b9000 r28 = c00000007d83a2c0
[ 350.613597] r13 = c000000001b00000 r29 = c0000000783cdf68
[ 350.613639] r14 = 0000000000000000 r30 = 0000000000000000
[ 350.613681] r15 = 0000000000000000 r31 = c00000007cffbbf0
[ 350.613723] ctr = c0000000004b9000 lr = c0000000004b9044
[ 350.613765] srr0 = 0000772f954dd48c srr1 = 800000000280f033
[ 350.613808] sprg0 = 0000000000000000 sprg1 = c000000001b00000
[ 350.613859] sprg2 = 0000772f9565a280 sprg3 = 0000000000000000
[ 350.613911] cr = 88002848 xer = 0000000020040000 dsisr = 42000000
[ 350.613962] dar = 0000772f95390000
[ 350.614031] fault dar = c000000244b278c0 dsisr = 00000000
[ 350.614073] SLB (0 entries):
[ 350.614157] lpcr = 0040000003d40413 sdr1 = 0000000000000000 last_inst = ffffffff
[ 350.614252] trap=0x1 | pc=0xc00000000013eb98 | msr=0x8000000000009033
followed by L1's QEMU reporting the following before stopping execution
of the nested guest:
KVM: unknown exit, hardware reason 1
NIP c00000000013eb98 LR c0000000004b9044 CTR c0000000004b9000 XER 0000000020040000 CPU#0
MSR 8000000000009033 HID0 0000000000000000 HF 8000000000000000 iidx 3 didx 3
TB 00000000 00000000 DECR 00000000
GPR00 c0000000004b9044 c00000007cffba30 c00000000178c100 c00000007ef52480
GPR04 0000000000000000 70616d00746f6f72 0000000000000020 c0000000783be440
GPR08 fffffffffffffffc c00000007ef52490 0000000000000004 b0616d0009eccdb2
GPR12 c0000000004b9000 c000000001b00000 0000000000000000 0000000000000000
GPR16 0000000000000000 0000000000000000 00007fffc24f3b50 00007fffc24fff58
GPR20 00000a1e96ece9d0 00000a1ea117c9b0 00000a1ea1184360 0000000000000003
GPR24 00000a1e96e9e124 00000000000007ff c00000007eb2f7a0 c00000007cffbb10
GPR28 c00000007d83a2c0 c0000000783cdf68 0000000000000000 c00000007cffbbf0
CR 88002848 [ L L - - E L G L ] RES ffffffffffffffff
SRR0 0000772f954dd48c SRR1 800000000280f033 PVR 00000000004e1202 VRSAVE 0000000000000000
SPRG0 0000000000000000 SPRG1 c000000001b00000 SPRG2 0000772f9565a280 SPRG3 0000000000000000
SPRG4 0000000000000000 SPRG5 0000000000000000 SPRG6 0000000000000000 SPRG7 0000000000000000
HSRR0 0000000000000000 HSRR1 0000000000000000
CFAR 0000000000000000
LPCR 0000000003d40413
PTCR 0000000000000000 DAR 0000772f95390000 DSISR 0000000042000000
Fix this by setting vcpu->arch.hcall_needed = 0 to indicate completion
of H_ENTER_NESTED before we exit to L0 userspace.
Fixes: 360cae313702 ("KVM: PPC: Book3S HV: Nested guest entry via hypercall")
Cc: linuxppc-dev@ozlabs.org
Cc: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
TRACE_INCLUDE_PATH and TRACE_INCLUDE_FILE are used by
<trace/define_trace.h>, so like that #include, they should
be outside #ifdef protection.
They also need to be #undefed before defining, in case multiple trace
headers are included by the same C file. This became the case on
book3e after commit cf4a6085151a ("powerpc/mm: Add missing tracepoint for
tlbie"), leading to the following build error:
CC arch/powerpc/kvm/powerpc.o
In file included from arch/powerpc/kvm/powerpc.c:51:0:
arch/powerpc/kvm/trace.h:9:0: error: "TRACE_INCLUDE_PATH" redefined
[-Werror]
#define TRACE_INCLUDE_PATH .
^
In file included from arch/powerpc/kvm/../mm/mmu_decl.h:25:0,
from arch/powerpc/kvm/powerpc.c:48:
./arch/powerpc/include/asm/trace.h:224:0: note: this is the location of
the previous definition
#define TRACE_INCLUDE_PATH asm
^
cc1: all warnings being treated as errors
Reported-by: Christian Zigotzky <chzigotzky@xenosoft.de>
Signed-off-by: Scott Wood <oss@buserror.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Some things that I missed due to travel, or that came in late.
Two fixes also going to stable:
- A revert of a buggy change to the 8xx TLB miss handlers.
- Our flushing of SPE (Signal Processing Engine) registers on fork
was broken.
Other changes:
- A change to the KVM decrementer emulation to use proper APIs.
- Some cleanups to the way we do code patching in the 8xx code.
- Expose the maximum possible memory for the system in
/proc/powerpc/lparcfg.
- Merge some updates from Scott: "a couple device tree updates, and a
fix for a missing prototype warning"
A few other minor fixes and a handful of fixes for our selftests.
Thanks to: Aravinda Prasad, Breno Leitao, Camelia Groza, Christophe
Leroy, Felipe Rechia, Joel Stanley, Naveen N. Rao, Paul Mackerras,
Scott Wood, Tyrel Datwyler"
* tag 'powerpc-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (21 commits)
selftests/powerpc: Fix compilation issue due to asm label
selftests/powerpc/cache_shape: Fix out-of-tree build
selftests/powerpc/switch_endian: Fix out-of-tree build
selftests/powerpc/pmu: Link ebb tests with -no-pie
selftests/powerpc/signal: Fix out-of-tree build
selftests/powerpc/ptrace: Fix out-of-tree build
powerpc/xmon: Relax frame size for clang
selftests: powerpc: Fix warning for security subdir
selftests/powerpc: Relax L1d miss targets for rfi_flush test
powerpc/process: Fix flush_all_to_thread for SPE
powerpc/pseries: add missing cpumask.h include file
selftests/powerpc: Fix ptrace tm failure
KVM: PPC: Use exported tb_to_ns() function in decrementer emulation
powerpc/pseries: Export maximum memory value
powerpc/8xx: Use patch_site for perf counters setup
powerpc/8xx: Use patch_site for memory setup patching
powerpc/code-patching: Add a helper to get the address of a patch_site
Revert "powerpc/8xx: Use L1 entry APG to handle _PAGE_ACCESSED for CONFIG_SWAP"
powerpc/8xx: add missing header in 8xx_mmu.c
powerpc/8xx: Add DT node for using the SEC engine of the MPC885
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"Notable changes:
- A large series to rewrite our SLB miss handling, replacing a lot of
fairly complicated asm with much fewer lines of C.
- Following on from that, we now maintain a cache of SLB entries for
each process and preload them on context switch. Leading to a 27%
speedup for our context switch benchmark on Power9.
- Improvements to our handling of SLB multi-hit errors. We now print
more debug information when they occur, and try to continue running
by flushing the SLB and reloading, rather than treating them as
fatal.
- Enable THP migration on 64-bit Book3S machines (eg. Power7/8/9).
- Add support for physical memory up to 2PB in the linear mapping on
64-bit Book3S. We only support up to 512TB as regular system
memory, otherwise the percpu allocator runs out of vmalloc space.
- Add stack protector support for 32 and 64-bit, with a per-task
canary.
- Add support for PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP.
- Support recognising "big cores" on Power9, where two SMT4 cores are
presented to us as a single SMT8 core.
- A large series to cleanup some of our ioremap handling and PTE
flags.
- Add a driver for the PAPR SCM (storage class memory) interface,
allowing guests to operate on SCM devices (acked by Dan).
- Changes to our ftrace code to handle very large kernels, where we
need to use a trampoline to get to ftrace_caller().
And many other smaller enhancements and cleanups.
Thanks to: Alan Modra, Alistair Popple, Aneesh Kumar K.V, Anton
Blanchard, Aravinda Prasad, Bartlomiej Zolnierkiewicz, Benjamin
Herrenschmidt, Breno Leitao, Cédric Le Goater, Christophe Leroy,
Christophe Lombard, Dan Carpenter, Daniel Axtens, Finn Thain, Gautham
R. Shenoy, Gustavo Romero, Haren Myneni, Hari Bathini, Jia Hongtao,
Joel Stanley, John Allen, Laurent Dufour, Madhavan Srinivasan, Mahesh
Salgaonkar, Mark Hairgrove, Masahiro Yamada, Michael Bringmann,
Michael Neuling, Michal Suchanek, Murilo Opsfelder Araujo, Nathan
Fontenot, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Oliver
O'Halloran, Paul Mackerras, Petr Vorel, Rashmica Gupta, Reza Arbab,
Rob Herring, Sam Bobroff, Samuel Mendoza-Jonas, Scott Wood, Stan
Johnson, Stephen Rothwell, Stewart Smith, Suraj Jitindar Singh, Tyrel
Datwyler, Vaibhav Jain, Vasant Hegde, YueHaibing, zhong jiang"
* tag 'powerpc-4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (221 commits)
Revert "selftests/powerpc: Fix out-of-tree build errors"
powerpc/msi: Fix compile error on mpc83xx
powerpc: Fix stack protector crashes on CPU hotplug
powerpc/traps: restore recoverability of machine_check interrupts
powerpc/64/module: REL32 relocation range check
powerpc/64s/radix: Fix radix__flush_tlb_collapsed_pmd double flushing pmd
selftests/powerpc: Add a test of wild bctr
powerpc/mm: Fix page table dump to work on Radix
powerpc/mm/radix: Display if mappings are exec or not
powerpc/mm/radix: Simplify split mapping logic
powerpc/mm/radix: Remove the retry in the split mapping logic
powerpc/mm/radix: Fix small page at boundary when splitting
powerpc/mm/radix: Fix overuse of small pages in splitting logic
powerpc/mm/radix: Fix off-by-one in split mapping logic
powerpc/ftrace: Handle large kernel configs
powerpc/mm: Fix WARN_ON with THP NUMA migration
selftests/powerpc: Fix out-of-tree build errors
powerpc/time: no steal_time when CONFIG_PPC_SPLPAR is not selected
powerpc/time: Only set CONFIG_ARCH_HAS_SCALED_CPUTIME on PPC64
powerpc/time: isolate scaled cputime accounting in dedicated functions.
...
|
|
This changes the KVM code that emulates the decrementer function to do
the conversion of decrementer values to time intervals in nanoseconds
by calling the tb_to_ns() function exported by the powerpc timer code,
in preference to open-coded arithmetic using values from the
decrementer_clockevent struct. Similarly, the HV-KVM code that did
the same conversion using arithmetic on tb_ticks_per_sec also now
uses tb_to_ns().
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
Pull KVM updates from Radim Krčmář:
"ARM:
- Improved guest IPA space support (32 to 52 bits)
- RAS event delivery for 32bit
- PMU fixes
- Guest entry hardening
- Various cleanups
- Port of dirty_log_test selftest
PPC:
- Nested HV KVM support for radix guests on POWER9. The performance
is much better than with PR KVM. Migration and arbitrary level of
nesting is supported.
- Disable nested HV-KVM on early POWER9 chips that need a particular
hardware bug workaround
- One VM per core mode to prevent potential data leaks
- PCI pass-through optimization
- merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base
s390:
- Initial version of AP crypto virtualization via vfio-mdev
- Improvement for vfio-ap
- Set the host program identifier
- Optimize page table locking
x86:
- Enable nested virtualization by default
- Implement Hyper-V IPI hypercalls
- Improve #PF and #DB handling
- Allow guests to use Enlightened VMCS
- Add migration selftests for VMCS and Enlightened VMCS
- Allow coalesced PIO accesses
- Add an option to perform nested VMCS host state consistency check
through hardware
- Automatic tuning of lapic_timer_advance_ns
- Many fixes, minor improvements, and cleanups"
* tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned
Revert "kvm: x86: optimize dr6 restore"
KVM: PPC: Optimize clearing TCEs for sparse tables
x86/kvm/nVMX: tweak shadow fields
selftests/kvm: add missing executables to .gitignore
KVM: arm64: Safety check PSTATE when entering guest and handle IL
KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips
arm/arm64: KVM: Enable 32 bits kvm vcpu events support
arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension()
KVM: arm64: Fix caching of host MDCR_EL2 value
KVM: VMX: enable nested virtualization by default
KVM/x86: Use 32bit xor to clear registers in svm.c
kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD
kvm: vmx: Defer setting of DR6 until #DB delivery
kvm: x86: Defer setting of CR2 until #PF delivery
kvm: x86: Add payload operands to kvm_multiple_exception
kvm: x86: Add exception payload fields to kvm_vcpu_events
kvm: x86: Add has_payload and payload to kvm_queued_exception
KVM: Documentation: Fix omission in struct kvm_vcpu_events
KVM: selftests: add Enlightened VMCS test
...
|
|
The powernv platform maintains 2 TCE tables for VFIO - a hardware TCE
table and a table with userspace addresses. These tables are radix trees,
we allocate indirect levels when they are written to. Since
the memory allocation is problematic in real mode, we have 2 accessors
to the entries:
- for virtual mode: it allocates the memory and it is always expected
to return non-NULL;
- fr real mode: it does not allocate and can return NULL.
Also, DMA windows can span to up to 55 bits of the address space and since
we never have this much RAM, such windows are sparse. However currently
the SPAPR TCE IOMMU driver walks through all TCEs to unpin DMA memory.
Since we maintain a userspace addresses table for VFIO which is a mirror
of the hardware table, we can use it to know which parts of the DMA
window have not been mapped and skip these so does this patch.
The bare metal systems do not have this problem as they use a bypass mode
of a PHB which maps RAM directly.
This helps a lot with sparse DMA windows, reducing the shutdown time from
about 3 minutes per 1 billion TCEs to a few seconds for 32GB sparse guest.
Just skipping the last level seems to be good enough.
As non-allocating accessor is used now in virtual mode as well, rename it
from IOMMU_TABLE_USERSPACE_ENTRY_RM (real mode) to _RO (read only).
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This disables the use of the streamlined entry path for radix guests
on early POWER9 chips that need the workaround added in commit
a25bd72badfa ("powerpc/mm/radix: Workaround prefetch issue with KVM",
2017-07-24), because the streamlined entry path does not include
that workaround. This also means that we can't do nested HV-KVM
on those chips.
Since the chips that need that workaround are the same ones that can't
run both radix and HPT guests at the same time on different threads of
a core, we use the existing 'no_mixing_hpt_and_radix' variable that
identifies those chips to identify when we can't use the new guest
entry path, and when we can't do nested virtualization.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
Back when I added -Werror in commit ba55bd74360e ("powerpc: Add
configurable -Werror for arch/powerpc") I did it by adding it to most
of the arch Makefiles.
At the time we excluded math-emu, because apparently it didn't build
cleanly. But that seems to have been fixed somewhere in the interim.
So move the -Werror addition to the top-level of the arch, this saves
us from repeating it in every Makefile and means we won't forget to
add it to any new sub-dirs.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
This adds a KVM_PPC_NO_HASH flag to the flags field of the
kvm_ppc_smmu_info struct, and arranges for it to be set when
running as a nested hypervisor, as an unambiguous indication
to userspace that HPT guests are not supported. Reporting the
KVM_CAP_PPC_MMU_HASH_V3 capability as false could be taken as
indicating only that the new HPT features in ISA V3.0 are not
supported, leaving it ambiguous whether pre-V3.0 HPT features
are supported.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
With this, userspace can enable a KVM-HV guest to run nested guests
under it.
The administrator can control whether any nested guests can be run;
setting the "nested" module parameter to false prevents any guests
becoming nested hypervisors (that is, any attempt to enable the nested
capability on a guest will fail). Guests which are already nested
hypervisors will continue to be so.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This merges in the "ppc-kvm" topic branch of the powerpc tree to get a
series of commits that touch both general arch/powerpc code and KVM
code. These commits will be merged both via the KVM tree and the
powerpc tree.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
|
|
This adds a list of valid shadow PTEs for each nested guest to
the 'radix' file for the guest in debugfs. This can be useful for
debugging.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
With this, the KVM-HV module can be loaded in a guest running under
KVM-HV, and if the hypervisor supports nested virtualization, this
guest can now act as a nested hypervisor and run nested guests.
This also adds some checks to inform userspace that HPT guests are not
supported by nested hypervisors (by returning false for the
KVM_CAP_PPC_MMU_HASH_V3 capability), and to prevent userspace from
configuring a guest to use HPT mode.
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
|
The hcall H_ENTER_NESTED takes two parameters: the address in L1 guest
memory of a hv_regs struct and the address of a pt_regs struct. The
hcall requests the L0 hypervisor to use the register values in these
structs to run a L2 guest and to return the exit state of the L2 guest
in these structs. These are in the endianness of the L1 guest, rather
than being always big-endian as is usually the case for PAPR
hypercalls.
This is convenient because it means that the L1 guest can pass the
address of the regs field in its kvm_vcpu_arch struct. This also
improves performance slightly by avoiding the need for two copies of
the pt_regs struct.
When reading/writing these structures, this patch handles the case
where the endianness of the L1 guest differs from that of the L0
hypervisor, by byteswapping the structures after reading and before
writing them back.
Since all the fields of the pt_regs are of the same type, i.e.,
unsigned long, we treat it as an array of unsigned longs. The fields
of struct hv_guest_state are not all the same, so its fields are
byteswapped individually.
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
|
