The function eeh_pe_state_mark_with_cfg() just performs the work of
eeh_pe_state_mark() and then, conditionally, the work of
eeh_pe_state_clear(). However it is only ever called with a constant
state such that the condition is always true, so replace it by direct
calls.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Move the call to eeh_dev_to_pe() up, so that later it's clear that
"pe" isn't NULL.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Change the name of the fields in eeh_rmv_data to clarify their usage.
Change "edev_list" to "removed_vf_list" because it does not contain
generic edevs, but rather only edevs that contain virtual functions
(which need to be removed during recovery).
Similarly, change "removed" to "removed_dev_count" because it is a
count of any removed devices, not just those in the above list.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Instances of struct eeh_pe are placed in a tree structure using the
fields "child_list" and "child", so place these next to each other
in the definition.
The field "child" is a list entry, so remove the unnecessary and
misleading use of the list initializer, LIST_HEAD(), on it.
The eeh_dev struct contains two list entry fields, called "list" and
"rmv_list". Rename them to "entry" and "rmv_entry" and, as above, stop
initializing them with LIST_HEAD().
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Remove the unnecessary cast through void * on the first parameter and
remove the unused second parameter (always NULL).
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The 'bus' member of struct eeh_dev is assigned to once but never used,
so remove it.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently a flag, EEH_POSTPONED_PROBE, is used to prevent an incorrect
message "EEH: No capable adapters found" from being displayed during
the boot of powernv systems.
It is necessary because, on powernv, the call to eeh_probe_devices()
made from eeh_init() is too early and EEH can't yet be enabled. A
second call is made later from eeh_pnv_post_init(), which succeeds.
(On pseries, the first call succeeds because PCI devices are set up
early enough and no second call is made.)
This can be simplified by moving the early call to eeh_probe_devices()
from eeh_init() (where it's seen by both platforms) to
pSeries_final_fixup(), so that each platform only calls
eeh_probe_devices() once, at a point where it can succeed.
This is slightly later in the boot sequence, but but still early
enough and it is now in the same place in the sequence for both
platforms (the pcibios_fixup hook).
The display of the message can be cleaned up as well, by moving it
into eeh_probe_devices().
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
eeh_add_to_parent_pe() sometimes removes the EEH_PE_KEEP flag, but it
incorrectly removes it from pe->type, instead of pe->state.
However, rather than clearing it from the correct field, remove it.
Inspection of the code shows that it can't ever have had any effect
(even if it had been cleared from the correct field), because the
field is never tested after it is cleared by the statement in
question.
The clear statement was added by commit 807a827d4e ("powerpc/eeh:
Keep PE during hotplug"), but it didn't explain why it was necessary.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If a device is removed during EEH processing (either by a driver's
handler or as part of recovery), it can lead to a null dereference
in eeh_pe_report_edev().
To handle this, skip devices that have been removed.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
If an error occurs during an unplug operation, it's possible for
eeh_dump_dev_log() to be called when edev->pdn is null, which
currently leads to dereferencing a null pointer.
Handle this by skipping the error log for those devices.
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The boot wrapper is currently built with -Os. By building with O2 we
can meaningfully reduce the time decompressing the kernel.
I tested by comparing 10 runs of each option in Qemu and on hardware.
The kernel is compressed with KERNEL_XZ built with GCC 8.2.0-7ubuntu1.
The values are counts of the timebase.
Qemu TCG powernv Power8:
Os O2 O3
median 10221123889 6201518438 6568186825
stddev 1361267211 429090641 657930076
improvement 39.33% 35.74%
Palmetto Power8:
Os O2 O3
median 50279 50599 35790
stddev 992144533 627130655 623721078
improvement 36.79% 37.13%
Romulus Power9:
Os O2 O3
median 670312391 454733720 448881398
stddev 157569 107276 108760
improvement 32.16% 33.03%
TCG was quite noisy, with every few runs producing an outlier. Even so,
O2 is faster than O3. On hardware the numbers were less noisy and O3 is
slightly faster than O2.
The wrapper size increases when moving from Os. Comparing zImage.epapr
to the existing Os build using bloat-o-meter:
Before=43401, After=56837 (13KB), chg +30.96%
Before=43401, After=64305 (20KB), chg +48.16%
I chose O2 for a balance between Qemu and hardware speed up.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This will avoid auto-vectorisation when building with higher
optimisation levels.
We don't know if the machine can support VSX and even if it's present
it's probably not going to be enabled at this point in boot.
These flag were both added prior to GCC 4.6 which is the minimum
compiler version supported by upstream, thanks to Segher for the
details.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
As of commit 10c77dba40 ("powerpc/boot: Fix build failure in 32-bit
boot wrapper") the opal code is hidden behind CONFIG_PPC64_BOOT_WRAPPER,
but the boot wrapper avoids include/linux, so it does not get the normal
Kconfig flags.
We can drop the guard entirely as in commit f8e8e69cea ("powerpc/boot:
Only build OPAL code when necessary") the makefile only includes opal.c
in the build if CONFIG_PPC64_BOOT_WRAPPER is set.
Fixes: 10c77dba40 ("powerpc/boot: Fix build failure in 32-bit boot wrapper")
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently the wrapper is built without including anything in
$(src)/include/, which means there are no CONFIG_ symbols defined.
This means the platform specific serial drivers were never enabled.
We now copy the definitions into the boot directory, so any C file can
now include autoconf.h to depend on configuration options.
Fixes: 866bfc75f4 ("powerpc: conditionally compile platform-specific serial drivers")
Signed-off-by: Joel Stanley <joel@jms.id.au>
[mpe: Fix to use $(objtree) to find autoconf.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
'default n' is the default value for any bool or tristate Kconfig
setting so there is no need to write it explicitly.
Also since commit f467c5640c ("kconfig: only write '# CONFIG_FOO
is not set' for visible symbols") the Kconfig behavior is the same
regardless of 'default n' being present or not:
...
One side effect of (and the main motivation for) this change is making
the following two definitions behave exactly the same:
config FOO
bool
config FOO
bool
default n
With this change, neither of these will generate a
'# CONFIG_FOO is not set' line (assuming FOO isn't selected/implied).
That might make it clearer to people that a bare 'default n' is
redundant.
...
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently when we get an unknown RTAS event it prints the type as
"Unknown" and no other useful information. Add the raw type code to the
log message so that we have something to work off.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The powerpc kernel uses setjmp which causes a warning when building
with clang:
In file included from arch/powerpc/xmon/xmon.c:51:
./arch/powerpc/include/asm/setjmp.h:15:13: error: declaration of
built-in function 'setjmp' requires inclusion of the header <setjmp.h>
[-Werror,-Wbuiltin-requires-header]
extern long setjmp(long *);
^
./arch/powerpc/include/asm/setjmp.h:16:13: error: declaration of
built-in function 'longjmp' requires inclusion of the header <setjmp.h>
[-Werror,-Wbuiltin-requires-header]
extern void longjmp(long *, long);
^
This *is* the header and we're not using the built-in setjump but
rather the one in arch/powerpc/kernel/misc.S. As the compiler warning
does not make sense, it for the files where setjmp is used.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
[mpe: Move subdir-ccflags in xmon/Makefile to not clobber -Werror]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The "count < sizeof(struct os_area_db)" comparison is type promoted to
size_t so negative values of "count" are treated as very high values
and we accidentally return success instead of a negative error code.
This doesn't really change runtime much but it fixes a static checker
warning.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
On a Power9 box we get a few screens full of these on boot. Drop
them to pr_debug.
[ 5.993645] nest_centaur6_imc performance monitor hardware support registered
[ 5.993728] nest_centaur7_imc performance monitor hardware support registered
[ 5.996510] core_imc performance monitor hardware support registered
[ 5.996569] nest_mba0_imc performance monitor hardware support registered
[ 5.996631] nest_mba1_imc performance monitor hardware support registered
[ 5.996685] nest_mba2_imc performance monitor hardware support registered
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Reviewed-by: Stewart Smith <stewart@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
instructions_to_print var is assigned value 16 and there is no
way to change it.
This patch replaces it by a constant.
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
When two processes crash at the same time, we sometimes encounter
interleaving in the middle of a line:
init[1]: segfault (11) at 0 nip 0 lr 0 code 1
init[1]: code: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
init[74]: segfault (11) at 10a74 nip 1000c198 lr 100078c8 code 1 in sh[10000000+14000]
XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
init[1]: code: XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
init[74]: code: 90010024 bf61000c 91490a7c 3fa01002 3be00000 7d3e4b78 3bbd0c20 3b600000
init[74]: code: 3b9d0040 7c7fe02e 2f830000 419e0028 <89230000> 2f890000 41be001c 4b7f6e79
This patch fixes it by preparing complete lines in a buffer and
printing it at once.
Fixes: 88b0fe1757 ("powerpc: Add show_user_instructions()")
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Use seq_buf_printf() not seq_buf_puts() which doesn't NULL terminate]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
As spotted by sparse:
arch/powerpc/kernel/process.c:1302:6: warning: symbol 'show_user_instructions' was not declared. Should it be static?
Fixes: 88b0fe1757 ("powerpc: Add show_user_instructions()")
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This patch fixes the following warnings, which are leftovers
from when __get_user() was replaced by probe_kernel_address().
arch/powerpc/kernel/process.c:1287:22: warning: incorrect type in argument 2 (different address spaces)
arch/powerpc/kernel/process.c:1287:22: expected void const *src
arch/powerpc/kernel/process.c:1287:22: got unsigned int [noderef] <asn:1>*<noident>
arch/powerpc/kernel/process.c:1319:21: warning: incorrect type in argument 2 (different address spaces)
arch/powerpc/kernel/process.c:1319:21: expected void const *src
arch/powerpc/kernel/process.c:1319:21: got unsigned int [noderef] <asn:1>*<noident>
Fixes: 7b051f665c ("powerpc: Use probe_kernel_address in show_instructions")
Reviewed-by: Murilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Currently _PAGE_DEVMAP bit is not preserved in mprotect(2) calls. As a
result we will see warnings such as:
BUG: Bad page map in process JobWrk0013 pte:800001803875ea25 pmd:7624381067
addr:00007f0930720000 vm_flags:280000f9 anon_vma: (null) mapping:ffff97f2384056f0 index:0
file:457-000000fe00000030-00000009-000000ca-00000001_2001.fileblock fault:xfs_filemap_fault [xfs] mmap:xfs_file_mmap [xfs] readpage: (null)
CPU: 3 PID: 15848 Comm: JobWrk0013 Tainted: G W 4.12.14-2.g7573215-default #1 SLE12-SP4 (unreleased)
Hardware name: Intel Corporation S2600WFD/S2600WFD, BIOS SE5C620.86B.01.00.0833.051120182255 05/11/2018
Call Trace:
dump_stack+0x5a/0x75
print_bad_pte+0x217/0x2c0
? enqueue_task_fair+0x76/0x9f0
_vm_normal_page+0xe5/0x100
zap_pte_range+0x148/0x740
unmap_page_range+0x39a/0x4b0
unmap_vmas+0x42/0x90
unmap_region+0x99/0xf0
? vma_gap_callbacks_rotate+0x1a/0x20
do_munmap+0x255/0x3a0
vm_munmap+0x54/0x80
SyS_munmap+0x1d/0x30
do_syscall_64+0x74/0x150
entry_SYSCALL_64_after_hwframe+0x3d/0xa2
...
when mprotect(2) gets used on DAX mappings. Also there is a wide variety
of other failures that can result from the missing _PAGE_DEVMAP flag
when the area gets used by get_user_pages() later.
Fix the problem by including _PAGE_DEVMAP in a set of flags that get
preserved by mprotect(2).
Fixes: 69660fd797 ("x86, mm: introduce _PAGE_DEVMAP")
Fixes: ebd3119793 ("powerpc/mm: Add devmap support for ppc64")
Cc: <stable@vger.kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
restore_hv_regs() is used to copy the hv_regs L1 wants to set to run the
nested (L2) guest into the vcpu structure. We need to sanitise these
values to ensure we don't let the L1 guest hypervisor do things we don't
want it to.
We don't let data address watchpoints or completed instruction address
breakpoints be set to match in hypervisor state.
We also don't let L1 enable features in the hypervisor facility status
and control register (HFSCR) for L2 which we have disabled for L1. That
is L2 will get the subset of features which the L0 hypervisor has
enabled for L1 and the features L1 wants to enable for L2. This could
mean we give L1 a hypervisor facility unavailable interrupt for a
facility it thinks it has enabled, however it shouldn't have enabled a
facility it itself doesn't have for the L2 guest.
We sanitise the registers when copying in the L2 hv_regs. We don't need
to sanitise when copying back the L1 hv_regs since these shouldn't be
able to contain invalid values as they're just what was copied out.
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>
This adds a one-reg register identifier which can be used to read and
set the virtual PTCR for the guest. This register identifies the
address and size of the virtual partition table for the guest, which
contains information about the nested guests under this guest.
Migrating this value is the only extra requirement for migrating a
guest which has nested guests (assuming of course that the destination
host supports nested virtualization in the kvm-hv module).
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>
When running as a nested hypervisor, this avoids reading hypervisor
privileged registers (specifically HFSCR, LPIDR and LPCR) at startup;
instead reasonable default values are used. This also avoids writing
LPIDR in the single-vcpu entry/exit path.
Also, this removes the check for CPU_FTR_HVMODE in kvmppc_mmu_hv_init()
since its only caller already checks this.
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>
This is only done at level 0, since only level 0 knows which physical
CPU a vcpu is running on. This does for nested guests what L0 already
did for its own guests, which is to flush the TLB on a pCPU when it
goes to run a vCPU there, and there is another vCPU in the same VM
which previously ran on this pCPU and has now started to run on another
pCPU. This is to handle the situation where the other vCPU touched
a mapping, moved to another pCPU and did a tlbiel (local-only tlbie)
on that new pCPU and thus left behind a stale TLB entry on this pCPU.
This introduces a limit on the the vcpu_token values used in the
H_ENTER_NESTED hcall -- they must now be less than NR_CPUS.
[paulus@ozlabs.org - made prev_cpu array be short[] to reduce
memory consumption.]
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>
This adds code to call the H_TLB_INVALIDATE hypercall when running as
a guest, in the cases where we need to invalidate TLBs (or other MMU
caches) as part of managing the mappings for a nested guest. Calling
H_TLB_INVALIDATE lets the nested hypervisor inform the parent
hypervisor about changes to partition-scoped page tables or the
partition table without needing to do hypervisor-privileged tlbie
instructions.
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>
When running a nested (L2) guest the guest (L1) hypervisor will use
the H_TLB_INVALIDATE hcall when it needs to change the partition
scoped page tables or the partition table which it manages. It will
use this hcall in the situations where it would use a partition-scoped
tlbie instruction if it were running in hypervisor mode.
The H_TLB_INVALIDATE hcall can invalidate different scopes:
Invalidate TLB for a given target address:
- This invalidates a single L2 -> L1 pte
- We need to invalidate any L2 -> L0 shadow_pgtable ptes which map the L2
address space which is being invalidated. This is because a single
L2 -> L1 pte may have been mapped with more than one pte in the
L2 -> L0 page tables.
Invalidate the entire TLB for a given LPID or for all LPIDs:
- Invalidate the entire shadow_pgtable for a given nested guest, or
for all nested guests.
Invalidate the PWC (page walk cache) for a given LPID or for all LPIDs:
- We don't cache the PWC, so nothing to do.
Invalidate the entire TLB, PWC and partition table for a given/all LPIDs:
- Here we re-read the partition table entry and remove the nested state
for any nested guest for which the first doubleword of the partition
table entry is now zero.
The H_TLB_INVALIDATE hcall takes as parameters the tlbie instruction
word (of which only the RIC, PRS and R fields are used), the rS value
(giving the lpid, where required) and the rB value (giving the IS, AP
and EPN values).
[paulus@ozlabs.org - adapted to having the partition table in guest
memory, added the H_TLB_INVALIDATE implementation, removed tlbie
instruction emulation, reworded the commit message.]
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>
When a host (L0) page which is mapped into a (L1) guest is in turn
mapped through to a nested (L2) guest we keep a reverse mapping (rmap)
so that these mappings can be retrieved later.
Whenever we create an entry in a shadow_pgtable for a nested guest we
create a corresponding rmap entry and add it to the list for the
L1 guest memslot at the index of the L1 guest page it maps. This means
at the L1 guest memslot we end up with lists of rmaps.
When we are notified of a host page being invalidated which has been
mapped through to a (L1) guest, we can then walk the rmap list for that
guest page, and find and invalidate all of the corresponding
shadow_pgtable entries.
In order to reduce memory consumption, we compress the information for
each rmap entry down to 52 bits -- 12 bits for the LPID and 40 bits
for the guest real page frame number -- which will fit in a single
unsigned long. To avoid a scenario where a guest can trigger
unbounded memory allocations, we scan the list when adding an entry to
see if there is already an entry with the contents we need. This can
occur, because we don't ever remove entries from the middle of a list.
A struct nested guest rmap is a list pointer and an rmap entry;
----------------
| next pointer |
----------------
| rmap entry |
----------------
Thus the rmap pointer for each guest frame number in the memslot can be
either NULL, a single entry, or a pointer to a list of nested rmap entries.
gfn memslot rmap array
-------------------------
0 | NULL | (no rmap entry)
-------------------------
1 | single rmap entry | (rmap entry with low bit set)
-------------------------
2 | list head pointer | (list of rmap entries)
-------------------------
The final entry always has the lowest bit set and is stored in the next
pointer of the last list entry, or as a single rmap entry.
With a list of rmap entries looking like;
----------------- ----------------- -------------------------
| list head ptr | ----> | next pointer | ----> | single rmap entry |
----------------- ----------------- -------------------------
| rmap entry | | rmap entry |
----------------- -------------------------
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
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>
Consider a normal (L1) guest running under the main hypervisor (L0),
and then a nested guest (L2) running under the L1 guest which is acting
as a nested hypervisor. L0 has page tables to map the address space for
L1 providing the translation from L1 real address -> L0 real address;
L1
|
| (L1 -> L0)
|
----> L0
There are also page tables in L1 used to map the address space for L2
providing the translation from L2 real address -> L1 read address. Since
the hardware can only walk a single level of page table, we need to
maintain in L0 a "shadow_pgtable" for L2 which provides the translation
from L2 real address -> L0 real address. Which looks like;
L2 L2
| |
| (L2 -> L1) |
| |
----> L1 | (L2 -> L0)
| |
| (L1 -> L0) |
| |
----> L0 --------> L0
When a page fault occurs while running a nested (L2) guest we need to
insert a pte into this "shadow_pgtable" for the L2 -> L0 mapping. To
do this we need to:
1. Walk the pgtable in L1 memory to find the L2 -> L1 mapping, and
provide a page fault to L1 if this mapping doesn't exist.
2. Use our L1 -> L0 pgtable to convert this L1 address to an L0 address,
or try to insert a pte for that mapping if it doesn't exist.
3. Now we have a L2 -> L0 mapping, insert this into our shadow_pgtable
Once this mapping exists we can take rc faults when hardware is unable
to automatically set the reference and change bits in the pte. On these
we need to:
1. Check the rc bits on the L2 -> L1 pte match, and otherwise reflect
the fault down to L1.
2. Set the rc bits in the L1 -> L0 pte which corresponds to the same
host page.
3. Set the rc bits in the L2 -> L0 pte.
As we reuse a large number of functions in book3s_64_mmu_radix.c for
this we also needed to refactor a number of these functions to take
an lpid parameter so that the correct lpid is used for tlb invalidations.
The functionality however has remained the same.
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>
When we are running as a nested hypervisor, we use a hypercall to
enter the guest rather than code in book3s_hv_rmhandlers.S. This means
that the hypercall handlers listed in hcall_real_table never get called.
There are some hypercalls that are handled there and not in
kvmppc_pseries_do_hcall(), which therefore won't get processed for
a nested guest.
To fix this, we add cases to kvmppc_pseries_do_hcall() to handle those
hypercalls, with the following exceptions:
- The HPT hypercalls (H_ENTER, H_REMOVE, etc.) are not handled because
we only support radix mode for nested guests.
- H_CEDE has to be handled specially because the cede logic in
kvmhv_run_single_vcpu assumes that it has been processed by the time
that kvmhv_p9_guest_entry() returns. Therefore we put a special
case for H_CEDE in kvmhv_p9_guest_entry().
For the XICS hypercalls, if real-mode processing is enabled, then the
virtual-mode handlers assume that they are being called only to finish
up the operation. Therefore we turn off the real-mode flag in the XICS
code when running as a nested hypervisor.
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>
This adds code to call the H_IPI and H_EOI hypercalls when we are
running as a nested hypervisor (i.e. without the CPU_FTR_HVMODE cpu
feature) and we would otherwise access the XICS interrupt controller
directly or via an OPAL call.
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>
This adds a new hypercall, H_ENTER_NESTED, which is used by a nested
hypervisor to enter one of its nested guests. The hypercall supplies
register values in two structs. Those values are copied by the level 0
(L0) hypervisor (the one which is running in hypervisor mode) into the
vcpu struct of the L1 guest, and then the guest is run until an
interrupt or error occurs which needs to be reported to L1 via the
hypercall return value.
Currently this assumes that the L0 and L1 hypervisors are the same
endianness, and the structs passed as arguments are in native
endianness. If they are of different endianness, the version number
check will fail and the hcall will be rejected.
Nested hypervisors do not support indep_threads_mode=N, so this adds
code to print a warning message if the administrator has set
indep_threads_mode=N, and treat it as Y.
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>
This starts the process of adding the code to support nested HV-style
virtualization. It defines a new H_SET_PARTITION_TABLE hypercall which
a nested hypervisor can use to set the base address and size of a
partition table in its memory (analogous to the PTCR register).
On the host (level 0 hypervisor) side, the H_SET_PARTITION_TABLE
hypercall from the guest is handled by code that saves the virtual
PTCR value for the guest.
This also adds code for creating and destroying nested guests and for
reading the partition table entry for a nested guest from L1 memory.
Each nested guest has its own shadow LPID value, different in general
from the LPID value used by the nested hypervisor to refer to it. The
shadow LPID value is allocated at nested guest creation time.
Nested hypervisor functionality is only available for a radix guest,
which therefore means a radix host on a POWER9 (or later) processor.
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>
kvmppc_unmap_pte() does a sequence of operations that are open-coded in
kvm_unmap_radix(). This extends kvmppc_unmap_pte() a little so that it
can be used by kvm_unmap_radix(), and makes kvm_unmap_radix() call it.
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>
The radix page fault handler accounts for all cases, including just
needing to insert a pte. This breaks it up into separate functions for
the two main cases; setting rc and inserting a pte.
This allows us to make the setting of rc and inserting of a pte
generic for any pgtable, not specific to the one for this guest.
[paulus@ozlabs.org - reduced diffs from previous code]
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>
kvmppc_mmu_radix_xlate() is used to translate an effective address
through the process tables. The process table and partition tables have
identical layout. Exploit this fact to make the kvmppc_mmu_radix_xlate()
function able to translate either an effective address through the
process tables or a guest real address through the partition tables.
[paulus@ozlabs.org - reduced diffs from previous code]
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>
When destroying a VM we return the LPID to the pool, however we never
zero the partition table entry. This is instead done when we reallocate
the LPID.
Zero the partition table entry on VM teardown before returning the LPID
to the pool. This means if we were running as a nested hypervisor the
real hypervisor could use this to determine when it can free resources.
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>
