Commit Graph

5201 Commits

Author SHA1 Message Date
Hari Bathini
7b1b3b4825 powerpc/fadump: consider f/w load area
OPAL loads kernel & initrd at 512MB offset (256MB size), also exported
as ibm,opal/dump/fw-load-area. So, if boot memory size of FADump is
less than 768MB, kernel memory to be exported as '/proc/vmcore' would
be overwritten by f/w while loading kernel & initrd. To avoid such a
scenario, enforce a minimum boot memory size of 768MB on OPAL platform
and skip using FADump if a newer F/W version loads kernel & initrd
above 768MB.

Also, irrespective of RMA size, set the minimum boot memory size
expected on pseries platform at 320MB. This is to avoid inflating the
minimum memory requirements on systems with 512M/1024M RMA size.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821381414.5656.1592867278535469652.stgit@hbathini.in.ibm.com
2019-09-14 00:04:45 +10:00
Hari Bathini
bec53196ad powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel
Add a new kernel config option, CONFIG_PRESERVE_FA_DUMP that ensures
that crash data, from previously crash'ed kernel, is preserved. This
helps in cases where FADump is not enabled but the subsequent memory
preserving kernel boot is likely to process this crash data. One
typical usecase for this config option is petitboot kernel.

As OPAL allows registering address with it in the first kernel and
retrieving it after MPIPL, use it to store the top of boot memory.
A kernel that intends to preserve crash data retrieves it and avoids
using memory beyond this address.

Move arch_reserved_kernel_pages() function as it is needed for both
FA_DUMP and PRESERVE_FA_DUMP configurations.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821375751.5656.11459483669542541602.stgit@hbathini.in.ibm.com
2019-09-14 00:04:45 +10:00
Hari Bathini
e4fc48fb4d powerpc/fadump: make crash memory ranges array allocation generic
Make allocate_crash_memory_ranges() and free_crash_memory_ranges()
functions generic to reuse them for memory management of all types of
dynamic memory range arrays. This change helps in memory management
of reserved ranges array to be added later.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821369863.5656.4375667005352155892.stgit@hbathini.in.ibm.com
2019-09-14 00:04:44 +10:00
Hari Bathini
5000a17afb powerpc/fadump: process architected register state data provided by firmware
Firmware provides architected register state data at the time of crash.
Process this data and build CPU notes to append to ELF core. In case
this data is missing or in unsupported format, at least append crashing
CPU's register data, to have something to work with in the vmcore file.

Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821367702.5656.5546683836236508389.stgit@hbathini.in.ibm.com
2019-09-14 00:04:44 +10:00
Hari Bathini
2790d01d1e powerpc/fadump: reset metadata address during clean up
During kexec boot, metadata address needs to be reset to avoid running
into errors interpreting stale metadata address, in case the kexec'ed
kernel crashes before metadata address could be setup again.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821346629.5656.10783321582005237813.stgit@hbathini.in.ibm.com
2019-09-14 00:04:43 +10:00
Hari Bathini
742a265acc powerpc/fadump: register kernel metadata address with opal
OPAL allows registering address with it in the first kernel and
retrieving it after MPIPL. Setup kernel metadata and register its
address with OPAL to use it for processing the crash dump.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821345011.5656.13567765019032928471.stgit@hbathini.in.ibm.com
2019-09-14 00:04:43 +10:00
Hari Bathini
41df592872 powerpc/fadump: add fadump support on powernv
Add basic callback functions for FADump on PowerNV platform.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821342072.5656.4346362203141486452.stgit@hbathini.in.ibm.com
2019-09-14 00:04:43 +10:00
Hari Bathini
6f5f193e84 powerpc/opal: add MPIPL interface definitions
MPIPL is Memory Preserving IPL supported from POWER9. This enables the
kernel to reset the system with memory 'preserved'. Also, it supports
copying memory from a source address to some destination address during
MPIPL boot. Add MPIPL interface definitions here to leverage these f/w
features in adding FADump support for PowerNV platform.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821340710.5656.10071829040515662624.stgit@hbathini.in.ibm.com
2019-09-14 00:04:43 +10:00
Hari Bathini
41a65d1618 pseries/fadump: define RTAS register/un-register callback functions
Move platform specific register/un-register code, the RTAS calls, to
register/un-register callback functions. This would also mean moving
code that initializes and prints the platform specific FADump data.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821332856.5656.16380417702046411631.stgit@hbathini.in.ibm.com
2019-09-14 00:04:42 +10:00
Hari Bathini
d3833a7010 powerpc/fadump: introduce callbacks for platform specific operations
Introduce callback functions for platform specific operations like
register, unregister, invalidate & such. Also, define place-holders
for the same on pSeries platform.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821330286.5656.15538934400074110770.stgit@hbathini.in.ibm.com
2019-09-14 00:04:42 +10:00
Hari Bathini
0226e55275 powerpc/fadump: move rtas specific definitions to platform code
Currently, FADump is only supported on pSeries but that is going to
change soon with FADump support being added on PowerNV platform. So,
move rtas specific definitions to platform code to allow FADump
to have multiple platforms support.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821328494.5656.16219929140866195511.stgit@hbathini.in.ibm.com
2019-09-14 00:04:41 +10:00
Hari Bathini
7f0ad11d3f powerpc/fadump: declare helper functions in internal header file
Declare helper functions, that can be reused by multiple platforms,
in the internal header file.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821320487.5656.2660730464212209984.stgit@hbathini.in.ibm.com
2019-09-14 00:04:41 +10:00
Hari Bathini
961cf26a98 powerpc/fadump: add helper functions
Add helper functions to setup & free CPU notes buffer and to find if a
given memory area is contiguous. Also, use boolean as return type for
the function that finds if boot memory area is contiguous. While at
it, save the virtual address of CPU notes buffer instead of physical
address as virtual address is used often.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821318971.5656.9281936950510635858.stgit@hbathini.in.ibm.com
2019-09-14 00:04:41 +10:00
Hari Bathini
ca986d7fa7 powerpc/fadump: move internal macros/definitions to a new header
Though asm/fadump.h is meant to be used by other components dealing
with FADump, it also has macros/definitions internal to FADump code.
Move them to a new header file used within FADump code. This also
makes way for refactoring platform specific FADump code.

Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821313134.5656.6597770626574392140.stgit@hbathini.in.ibm.com
2019-09-14 00:04:41 +10:00
Michael Ellerman
dac39f7885 powerpc/64s: Remove overlaps_kvm_tmp()
kvm_tmp is now in .text and so doesn't need a special overlap check.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190911115746.12433-2-mpe@ellerman.id.au
2019-09-14 00:04:40 +10:00
Michael Ellerman
1b7f3b6c43 powerpc/eeh: Fix build with STACKTRACE=n
The build breaks when STACKTRACE=n, eg. skiroot_defconfig:

  arch/powerpc/kernel/eeh_event.c:124:23: error: implicit declaration of function 'stack_trace_save'

Fix it with some ifdefs for now.

Fixes: 25baf3d816 ("powerpc/eeh: Defer printing stack trace")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-09-14 00:01:14 +10:00
Greg Kurz
6ccb4ac2bf powerpc/xive: Fix bogus error code returned by OPAL
There's a bug in skiboot that causes the OPAL_XIVE_ALLOCATE_IRQ call
to return the 32-bit value 0xffffffff when OPAL has run out of IRQs.
Unfortunatelty, OPAL return values are signed 64-bit entities and
errors are supposed to be negative. If that happens, the linux code
confusingly treats 0xffffffff as a valid IRQ number and panics at some
point.

A fix was recently merged in skiboot:

e97391ae2bb5 ("xive: fix return value of opal_xive_allocate_irq()")

but we need a workaround anyway to support older skiboots already
in the field.

Internally convert 0xffffffff to OPAL_RESOURCE which is the usual error
returned upon resource exhaustion.

Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/156821713818.1985334.14123187368108582810.stgit@bahia.lan
2019-09-12 09:27:05 +10:00
Vasant Hegde
587164cd59 powerpc/powernv: Add new opal message type
We have OPAL_MSG_PRD message type to pass prd related messages from
OPAL to `opal-prd`. It can handle messages upto 64 bytes. We have a
requirement to send bigger than 64 bytes of data from OPAL to
`opal-prd`. Lets add new message type (OPAL_MSG_PRD2) to pass bigger
data.

Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
[mpe: Make the error string clear that it's the PRD2 event that failed]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190826065701.8853-2-hegdevasant@linux.vnet.ibm.com
2019-09-12 09:27:00 +10:00
Segher Boessenkool
aa497d4352 powerpc: Add attributes for setjmp/longjmp
The setjmp function should be declared as "returns_twice", or bad
things can happen[1]. This does not actually change generated code in
my testing.

The longjmp function should be declared as "noreturn", so that the
compiler can optimise calls to it better. This makes the generated
code a little shorter.

1: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-returns_005ftwice-function-attribute

Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c02ce4a573f3bac907e2c70957a2d1275f910013.1567605586.git.segher@kernel.crashing.org
2019-09-12 09:26:59 +10:00
Paolo Bonzini
32d1d15c52 KVM/arm updates for 5.4
- New ITS translation cache
 - Allow up to 512 CPUs to be supported with GICv3 (for real this time)
 - Now call kvm_arch_vcpu_blocking early in the blocking sequence
 - Tidy-up device mappings in S2 when DIC is available
 - Clean icache invalidation on VMID rollover
 - General cleanup
 -----BEGIN PGP SIGNATURE-----
 
 iQJDBAABCgAtFiEEn9UcU+C1Yxj9lZw9I9DQutE9ekMFAl12QlAPHG1hekBrZXJu
 ZWwub3JnAAoJECPQ0LrRPXpDXxUQAMd+GlOlmTXqEiuKudVApTkl6WIebfh0vkn6
 /1j8yNgJqRtZEY/YqE/XhAaqz1tx88VtzqSrNG4Pmrl9rDHMD9mDuk+w5UvEN2vy
 D5/nEe/wnzyVpuROBlHhsRbCRkT/6dNpnDnydwxCUqQPhfsAHnTNx6IygVzH9BHS
 D/1+KLI1imW8YziSSf6SGlIKJtk0eo5qo/aT6/mhb+e18Dobax3miItZL4mAqFPd
 tCV8fvOLb/phdSmOZuD/3XF9JOodk2ycvF9MW9Rp/FxDx9HULCXPv/3KnoHg9ca5
 QSGz1Chj0C2avaQJ4GbHZnZZjdvL2TmVxMpixocc/VZCqlO3ifRKf91t/rq4cElG
 HxLE9AX6kqW6UK66RHUQiHxjqRG8ynz8xEmlhwd7YhCLmtmJSXLTrmc2ABf64+BT
 RaexRa3h6D19fLBcMN5gpP8I48XaRpfxg6E/jCw5ZEr/8zhzLajFnE89ftgRR04f
 bSXOnj0kAhrBZ6jRTEata1MrFAt58wiaulxTxgMlnj1hHpqA3b+x6woRECAEVOlc
 6JJuzReJSBuCJL/rVtXGF31mXNnqUo+oTcDpQSle/fDtQ/44+xlYj6V/ZeFIRHAz
 nwUw9DHyZ/JMSwPNsqtdzCnLths1rNw34A7VgdVWiqiPYEcGGUnMzkRrXKMYjjJn
 LD4+Rh/e
 =0dD/
 -----END PGP SIGNATURE-----

Merge tag 'kvmarm-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm updates for 5.4

- New ITS translation cache
- Allow up to 512 CPUs to be supported with GICv3 (for real this time)
- Now call kvm_arch_vcpu_blocking early in the blocking sequence
- Tidy-up device mappings in S2 when DIC is available
- Clean icache invalidation on VMID rollover
- General cleanup
2019-09-10 19:09:14 +02:00
Jordan Niethe
67c87892e2 powerpc: Remove empty comment
Commit 2874c5fd28 ("treewide: Replace GPLv2 boilerplate/reference with
SPDX - rule 152") left an empty comment in machdep.h, as the boilerplate
was the only text in the comment. Remove the empty comment.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813051212.6387-1-jniethe5@gmail.com
2019-09-05 14:22:41 +10:00
Nicholas Piggin
2275d7b575 powerpc/64s/radix: introduce options to disable use of the tlbie instruction
Introduce two options to control the use of the tlbie instruction. A
boot time option which completely disables the kernel using the
instruction, this is currently incompatible with HASH MMU, KVM, and
coherent accelerators.

And a debugfs option can be switched at runtime and avoids using tlbie
for invalidating CPU TLBs for normal process and kernel address
mappings. Coherent accelerators are still managed with tlbie, as will
KVM partition scope translations.

Cross-CPU TLB flushing is implemented with IPIs and tlbiel. This is a
basic implementation which does not attempt to make any optimisation
beyond the tlbie implementation.

This is useful for performance testing among other things. For example
in certain situations on large systems, using IPIs may be faster than
tlbie as they can be directed rather than broadcast. Later we may also
take advantage of the IPIs to do more interesting things such as trim
the mm cpumask more aggressively.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-7-npiggin@gmail.com
2019-09-05 14:22:41 +10:00
Nicholas Piggin
fd13daea5f powerpc/64s: make mmu_partition_table_set_entry TLB flush optional
No functional change.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-4-npiggin@gmail.com
2019-09-05 14:22:40 +10:00
Nicholas Piggin
99161de3a2 powerpc/64s/radix: tidy up TLB flushing code
There should be no functional changes.

- Use calls to existing radix_tlb.c functions in flush_partition.

- Rename radix__flush_tlb_lpid to radix__flush_all_lpid and similar,
  because they flush everything, matching flush_all_mm rather than
  flush_tlb_mm for the lpid.

- Remove some unused radix_tlb.c flush primitives.

Signed-off: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-3-npiggin@gmail.com
2019-09-05 14:22:40 +10:00
Nicholas Piggin
ed6546bdc6 powerpc/64s: remove register_process_table callback
This callback is only required because the partition table init comes
before process table allocation on powernv (aka bare metal aka native).

Change the order to allocate the process table first, and remove the
callback.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-2-npiggin@gmail.com
2019-09-05 14:22:40 +10:00
Oliver O'Halloran
25baf3d816 powerpc/eeh: Defer printing stack trace
Currently we print a stack trace in the event handler to help with
debugging EEH issues. In the case of suprise hot-unplug this is unneeded,
so we want to prevent printing the stack trace unless we know it's due to
an actual device error. To accomplish this, we can save a stack trace at
the point of detection and only print it once the EEH recovery handler has
determined the freeze was due to an actual error.

Since the whole point of this is to prevent spurious EEH output we also
move a few prints out of the detection thread, or mark them as pr_debug
so anyone interested can get output from the eeh_check_dev_failure()
if they want.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903101605.2890-6-oohall@gmail.com
2019-09-05 14:22:38 +10:00
Oliver O'Halloran
5ef753ae43 powerpc/eeh: Fix race when freeing PDNs
When hot-adding devices we rely on the hotplug driver to create pci_dn's
for the devices under the hotplug slot. Converse, when hot-removing the
driver will remove the pci_dn's that it created. This is a problem because
the pci_dev is still live until it's refcount drops to zero. This can
happen if the driver is slow to tear down it's internal state. Ideally, the
driver would not attempt to perform any config accesses to the device once
it's been marked as removed, but sometimes it happens. As a result, we
might attempt to access the pci_dn for a device that has been torn down and
the kernel may crash as a result.

To fix this, don't free the pci_dn unless the corresponding pci_dev has
been released.  If the pci_dev is still live, then we mark the pci_dn with
a flag that indicates the pci_dev's release function should free it.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190903101605.2890-3-oohall@gmail.com
2019-09-05 14:22:37 +10:00
Nicholas Piggin
a243281195 powerpc/64s/exception: move head-64.h exception code to exception-64s.S
The head-64.h code should deal only with the head code sections
and offset calculations.

No generated code change except BUG line number constants.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802105709.27696-19-npiggin@gmail.com
2019-08-30 10:32:36 +10:00
Nicholas Piggin
9ca766f989 powerpc/64s/pseries: machine check convert to use common event code
The common machine_check_event data structures and queues are mostly
platform independent, with powernv decoding SRR1/DSISR/etc., into
machine_check_event objects.

This patch converts pseries to use this infrastructure by decoding
fwnmi/rtas data into machine_check_event objects.

This allows queueing to be used by a subsequent change to delay the
virtual mode handling of machine checks that occur in kernel space
where it is unsafe to switch immediately to virtual mode, similarly
to powernv.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fix implicit fallthrough warnings in mce_handle_error()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190802105709.27696-10-npiggin@gmail.com
2019-08-30 10:32:35 +10:00
Anshuman Khandual
2efbc58f15 powerpc/pseries/svm: Force SWIOTLB for secure guests
SWIOTLB checks range of incoming CPU addresses to be bounced and sees if
the device can access it through its DMA window without requiring bouncing.
In such cases it just chooses to skip bouncing. But for cases like secure
guests on powerpc platform all addresses need to be bounced into the shared
pool of memory because the host cannot access it otherwise. Hence the need
to do the bouncing is not related to device's DMA window and use of bounce
buffers is forced by setting swiotlb_force.

Also, connect the shared memory conversion functions into the
ARCH_HAS_MEM_ENCRYPT hooks and call swiotlb_update_mem_attributes() to
convert SWIOTLB's memory pool to shared memory.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
[ bauerman: Use ARCH_HAS_MEM_ENCRYPT hooks to share swiotlb memory pool. ]
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-15-bauerman@linux.ibm.com
2019-08-30 09:55:41 +10:00
Ram Pai
256ba2c168 powerpc/pseries/svm: Unshare all pages before kexecing a new kernel
A new kernel deserves a clean slate. Any pages shared with the hypervisor
is unshared before invoking the new kernel. However there are exceptions.
If the new kernel is invoked to dump the current kernel, or if there is a
explicit request to preserve the state of the current kernel, unsharing
of pages is skipped.

NOTE: While testing crashkernel, make sure at least 256M is reserved for
crashkernel. Otherwise SWIOTLB allocation will fail and crash kernel will
fail to boot.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-11-bauerman@linux.ibm.com
2019-08-30 09:55:40 +10:00
Anshuman Khandual
d5394c059d powerpc/pseries/svm: Use shared memory for Debug Trace Log (DTL)
Secure guests need to share the DTL buffers with the hypervisor. To that
end, use a kmem_cache constructor which converts the underlying buddy
allocated SLUB cache pages into shared memory.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-10-bauerman@linux.ibm.com
2019-08-30 09:55:40 +10:00
Anshuman Khandual
bd104e6db6 powerpc/pseries/svm: Use shared memory for LPPACA structures
LPPACA structures need to be shared with the host. Hence they need to be in
shared memory. Instead of allocating individual chunks of memory for a
given structure from memblock, a contiguous chunk of memory is allocated
and then converted into shared memory. Subsequent allocation requests will
come from the contiguous chunk which will be always shared memory for all
structures.

While we are able to use a kmem_cache constructor for the Debug Trace Log,
LPPACAs are allocated very early in the boot process (before SLUB is
available) so we need to use a simpler scheme here.

Introduce helper is_svm_platform() which uses the S bit of the MSR to tell
whether we're running as a secure guest.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-9-bauerman@linux.ibm.com
2019-08-30 09:55:40 +10:00
Sukadev Bhattiprolu
7f70c3815a powerpc: Introduce the MSR_S bit
Protected Execution Facility (PEF) is an architectural change for
POWER 9 that enables Secure Virtual Machines (SVMs). When enabled,
PEF adds a new higher privileged mode, called Ultravisor mode, to
POWER architecture.

The hardware changes include the following:

  * There is a new bit in the MSR that determines whether the current
    process is running in secure mode, MSR(S) bit 41. MSR(S)=1, process
    is in secure mode, MSR(s)=0 process is in normal mode.

  * The MSR(S) bit can only be set by the Ultravisor.

  * HRFID cannot be used to set the MSR(S) bit. If the hypervisor needs
    to return to a SVM it must use an ultracall. It can determine if
    the VM it is returning to is secure.

  * The privilege of a process is now determined by three MSR bits,
    MSR(S, HV, PR). In each of the tables below the modes are listed
    from least privilege to highest privilege. The higher privilege
    modes can access all the resources of the lower privilege modes.

    **Secure Mode MSR Settings**

       +---+---+---+---------------+
       | S | HV| PR|Privilege      |
       +===+===+===+===============+
       | 1 | 0 | 1 | Problem       |
       +---+---+---+---------------+
       | 1 | 0 | 0 | Privileged(OS)|
       +---+---+---+---------------+
       | 1 | 1 | 0 | Ultravisor    |
       +---+---+---+---------------+
       | 1 | 1 | 1 | Reserved      |
       +---+---+---+---------------+

    **Normal Mode MSR Settings**

       +---+---+---+---------------+
       | S | HV| PR|Privilege      |
       +===+===+===+===============+
       | 0 | 0 | 1 | Problem       |
       +---+---+---+---------------+
       | 0 | 0 | 0 | Privileged(OS)|
       +---+---+---+---------------+
       | 0 | 1 | 0 | Hypervisor    |
       +---+---+---+---------------+
       | 0 | 1 | 1 | Problem (HV)  |
       +---+---+---+---------------+

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[ cclaudio: Update the commit message ]
Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-7-bauerman@linux.ibm.com
2019-08-30 09:55:40 +10:00
Ram Pai
f7777e008c powerpc/pseries/svm: Add helpers for UV_SHARE_PAGE and UV_UNSHARE_PAGE
These functions are used when the guest wants to grant the hypervisor
access to certain pages.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-6-bauerman@linux.ibm.com
2019-08-30 09:55:40 +10:00
Ram Pai
6a9c930bd7 powerpc/prom_init: Add the ESM call to prom_init
Make the Enter-Secure-Mode (ESM) ultravisor call to switch the VM to secure
mode. Pass kernel base address and FDT address so that the Ultravisor is
able to verify the integrity of the VM using information from the ESM blob.

Add "svm=" command line option to turn on switching to secure mode.

Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[ andmike: Generate an RTAS os-term hcall when the ESM ucall fails. ]
Signed-off-by: Michael Anderson <andmike@linux.ibm.com>
[ bauerman: Cleaned up the code a bit. ]
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-5-bauerman@linux.ibm.com
2019-08-30 09:54:35 +10:00
Thiago Jung Bauermann
136bc0397a powerpc/pseries: Introduce option to build secure virtual machines
Introduce CONFIG_PPC_SVM to control support for secure guests and include
Ultravisor-related helpers when it is selected

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820021326.6884-3-bauerman@linux.ibm.com
2019-08-30 09:53:28 +10:00
Michael Ellerman
9044adca78 Merge branch 'topic/ppc-kvm' into next
Merge our ppc-kvm topic branch to bring in the Ultravisor support
patches.
2019-08-30 09:52:57 +10:00
Sukadev Bhattiprolu
6c85b7bc63 powerpc/kvm: Use UV_RETURN ucall to return to ultravisor
When an SVM makes an hypercall or incurs some other exception, the
Ultravisor usually forwards (a.k.a. reflects) the exceptions to the
Hypervisor. After processing the exception, Hypervisor uses the
UV_RETURN ultracall to return control back to the SVM.

The expected register state on entry to this ultracall is:

* Non-volatile registers are restored to their original values.
* If returning from an hypercall, register R0 contains the return value
  (unlike other ultracalls) and, registers R4 through R12 contain any
  output values of the hypercall.
* R3 contains the ultracall number, i.e UV_RETURN.
* If returning with a synthesized interrupt, R2 contains the
  synthesized interrupt number.

Thanks to input from Paul Mackerras, Ram Pai and Mike Anderson.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190822034838.27876-8-cclaudio@linux.ibm.com
2019-08-30 09:40:16 +10:00
Claudio Carvalho
5223134029 powerpc/mm: Write to PTCR only if ultravisor disabled
In ultravisor enabled systems, PTCR becomes ultravisor privileged only
for writing and an attempt to write to it will cause a Hypervisor
Emulation Assitance interrupt.

This patch uses the set_ptcr_when_no_uv() function to restrict PTCR
writing to only when ultravisor is disabled.

Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190822034838.27876-6-cclaudio@linux.ibm.com
2019-08-30 09:40:16 +10:00
Michael Anderson
139a1d2842 powerpc/mm: Use UV_WRITE_PATE ucall to register a PATE
When Ultravisor (UV) is enabled, the partition table is stored in secure
memory and can only be accessed via the UV. The Hypervisor (HV) however
maintains a copy of the partition table in normal memory to allow Nest MMU
translations to occur (for normal VMs). The HV copy includes partition
table entries (PATE)s for secure VMs which would currently be unused
(Nest MMU translations cannot access secure memory) but they would be
needed as we add functionality.

This patch adds the UV_WRITE_PATE ucall which is used to update the PATE
for a VM (both normal and secure) when Ultravisor is enabled.

Signed-off-by: Michael Anderson <andmike@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
[ cclaudio: Write the PATE in HV's table before doing that in UV's ]
Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Reviewed-by: Ryan Grimm <grimm@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190822034838.27876-5-cclaudio@linux.ibm.com
2019-08-30 09:40:15 +10:00
Claudio Carvalho
bb04ffe85e powerpc/powernv: Introduce FW_FEATURE_ULTRAVISOR
In PEF enabled systems, some of the resources which were previously
hypervisor privileged are now ultravisor privileged and controlled by
the ultravisor firmware.

This adds FW_FEATURE_ULTRAVISOR to indicate if PEF is enabled.

The host kernel can use FW_FEATURE_ULTRAVISOR, for instance, to skip
accessing resources (e.g. PTCR and LDBAR) in case PEF is enabled.

Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
[ andmike: Device node name to "ibm,ultravisor" ]
Signed-off-by: Michael Anderson <andmike@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190822034838.27876-4-cclaudio@linux.ibm.com
2019-08-30 09:40:15 +10:00
Claudio Carvalho
a49dddbdb0 powerpc/kernel: Add ucall_norets() ultravisor call handler
The ultracalls (ucalls for short) allow the Secure Virtual Machines
(SVM)s and hypervisor to request services from the ultravisor such as
accessing a register or memory region that can only be accessed when
running in ultravisor-privileged mode.

This patch adds the ucall_norets() ultravisor call handler.

The specific service needed from an ucall is specified in register
R3 (the first parameter to the ucall). Other parameters to the
ucall, if any, are specified in registers R4 through R12.

Return value of all ucalls is in register R3. Other output values
from the ucall, if any, are returned in registers R4 through R12.

Each ucall returns specific error codes, applicable in the context
of the ucall. However, like with the PowerPC Architecture Platform
Reference (PAPR), if no specific error code is defined for a particular
situation, then the ucall will fallback to an erroneous
parameter-position based code. i.e U_PARAMETER, U_P2, U_P3 etc depending
on the ucall parameter that may have caused the error.

Every host kernel (powernv) needs to be able to do ucalls in case it
ends up being run in a machine with ultravisor enabled. Otherwise, the
kernel may crash early in boot trying to access ultravisor resources,
for instance, trying to set the partition table entry 0. Secure guests
also need to be able to do ucalls and its kernel may not have
CONFIG_PPC_POWERNV=y. For that reason, the ucall.S file is placed under
arch/powerpc/kernel.

If ultravisor is not enabled, the ucalls will be redirected to the
hypervisor which must handle/fail the call.

Thanks to inputs from Ram Pai and Michael Anderson.

Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190822034838.27876-3-cclaudio@linux.ibm.com
2019-08-30 09:40:15 +10:00
Claudio Carvalho
70ed86f4de powerpc: Add PowerPC Capabilities ELF note
Add the PowerPC name and the PPC_ELFNOTE_CAPABILITIES type in the
kernel binary ELF note. This type is a bitmap that can be used to
advertise kernel capabilities to userland.

This patch also defines PPCCAP_ULTRAVISOR_BIT as being the bit zero.

Suggested-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Claudio Carvalho <cclaudio@linux.ibm.com>
[ maxiwell: Define the 'PowerPC' type in the elfnote.h ]
Signed-off-by: Maxiwell S. Garcia <maxiwell@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190829155021.2915-2-maxiwell@linux.ibm.com
2019-08-30 09:40:15 +10:00
Alexey Kardashevskiy
a102f139aa powerpc/powernv/ioda: Remove obsolete iommu_table_ops::exchange callbacks
As now we have xchg_no_kill/tce_kill, these are not used anymore so
remove them.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190829085252.72370-6-aik@ozlabs.ru
2019-08-30 09:40:15 +10:00
Alexey Kardashevskiy
35872480da powerpc/powernv/ioda: Split out TCE invalidation from TCE updates
At the moment updates in a TCE table are made by iommu_table_ops::exchange
which update one TCE and invalidates an entry in the PHB/NPU TCE cache
via set of registers called "TCE Kill" (hence the naming).
Writing a TCE is a simple xchg() but invalidating the TCE cache is
a relatively expensive OPAL call. Mapping a 100GB guest with PCI+NPU
passed through devices takes about 20s.

Thankfully we can do better. Since such big mappings happen at the boot
time and when memory is plugged/onlined (i.e. not often), these requests
come in 512 pages so we call call OPAL 512 times less which brings 20s
from the above to less than 10s. Also, since TCE caches can be flushed
entirely, calling OPAL for 512 TCEs helps skiboot [1] to decide whether
to flush the entire cache or not.

This implements 2 new iommu_table_ops callbacks:
- xchg_no_kill() to update a single TCE with no TCE invalidation;
- tce_kill() to invalidate multiple TCEs.
This uses the same xchg_no_kill() callback for IODA1/2.

This implements 2 new wrappers on top of the new callbacks similar to
the existing iommu_tce_xchg().

This does not use the new callbacks yet, the next patches will;
so this should not cause any behavioral change.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190829085252.72370-2-aik@ozlabs.ru
2019-08-30 09:40:14 +10:00
Christoph Hellwig
f2902a2fb4 powerpc: use the generic dma coherent remap allocator
This switches to using common code for the DMA allocations, including
potential use of the CMA allocator if configured.

Switching to the generic code enables DMA allocations from atomic
context, which is required by the DMA API documentation, and also
adds various other minor features drivers start relying upon.  It
also makes sure we have on tested code base for all architectures
that require uncached pte bits for coherent DMA allocations.

Another advantage is that consistent memory allocations now share
the general vmalloc pool instead of needing an explicit careout
from it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Christophe Leroy <christophe.leroy@c-s.fr> # tested on 8xx
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190814132230.31874-2-hch@lst.de
2019-08-28 23:19:34 +10:00
Christophe Leroy
e0291f1dec powerpc/32: drop CPU_FTR_UNIFIED_ID_CACHE
Only 601 and e200 have unified I/D cache.

Drop the feature and use CONFIG_PPC_BOOK3S_601 and CONFIG_E200.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b5902144266d2f4eed1ffea53915bd0245841e02.1566834712.git.christophe.leroy@c-s.fr
2019-08-28 23:19:33 +10:00
Christophe Leroy
88fb309409 powerpc/32s: drop CPU_FTR_USE_RTC feature
CPU_FTR_USE_RTC feature only applies to powerpc601.

Drop this feature and replace it with tests on CONFIG_PPC_BOOK3S_601.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/170411e2360861f4a95c21faad43519a08bc4040.1566834712.git.christophe.leroy@c-s.fr
2019-08-28 23:19:33 +10:00
Christophe Leroy
12c3f1fd87 powerpc/32s: get rid of CPU_FTR_601 feature
Now that 601 is exclusive from other 6xx, CPU_FTR_601 and
associated fixups are useless.

Drop this feature and use #ifdefs instead.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ecdb7194a17dbfa01865df6a82979533adc2c70b.1566834712.git.christophe.leroy@c-s.fr
2019-08-28 23:19:33 +10:00
Christophe Leroy
63ce271b5e powerpc/prom: convert PROM_BUG() to standard trap
Prior to commit 1bd98d7fbaf5 ("ppc64: Update BUG handling based on
ppc32"), BUG() family was using BUG_ILLEGAL_INSTRUCTION which
was an invalid instruction opcode to trap into program check
exception.

That commit converted them to using standard trap instructions,
but prom/prom_init and their PROM_BUG() macro were left over.
head_64.S and exception-64s.S were left aside as well.

Convert them to using the standard BUG infrastructure.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/cdaf4bbbb64c288a077845846f04b12683f8875a.1566817807.git.christophe.leroy@c-s.fr
2019-08-28 11:31:18 +10:00
Christopher M. Riedl
405efc5980 powerpc/spinlocks: Fix oops in __spin_yield() on bare metal
Booting w/ppc64le_defconfig + CONFIG_PREEMPT on bare metal results in
the oops below due to calling into __spin_yield() when not running in
an SPLPAR, which means lppaca pointers are NULL.

We fixed a similar case previously in commit a6201da34f ("powerpc:
Fix oops due to bad access of lppaca on bare metal"), by adding SPLPAR
checks in lppaca_shared_proc(). However when PREEMPT is enabled we can
call __spin_yield() directly from arch_spin_yield().

To fix it add spin_yield() and rw_yield() which check that
shared-processor LPAR is enabled before calling the SPLPAR-only
implementation of each.

  BUG: Kernel NULL pointer dereference at 0x00000100
  Faulting instruction address: 0xc000000000097f88
  Oops: Kernel access of bad area, sig: 7 [#1]
  LE PAGE_SIZE=64K MMU=Radix MMU=Hash PREEMPT SMP NR_CPUS=2048 NUMA PowerNV
  Modules linked in:
  CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.2.0-rc6-00491-g249155c20f9b #28
  NIP:  c000000000097f88 LR: c000000000c07a88 CTR: c00000000015ca10
  REGS: c0000000727079f0 TRAP: 0300   Not tainted  (5.2.0-rc6-00491-g249155c20f9b)
  MSR:  9000000002009033 <SF,HV,VEC,EE,ME,IR,DR,RI,LE>  CR: 84000424  XER: 20040000
  CFAR: c000000000c07a84 DAR: 0000000000000100 DSISR: 00080000 IRQMASK: 1
  GPR00: c000000000c07a88 c000000072707c80 c000000001546300 c00000007be38a80
  GPR04: c0000000726f0c00 0000000000000002 c00000007279c980 0000000000000100
  GPR08: c000000001581b78 0000000080000001 0000000000000008 c00000007279c9b0
  GPR12: 0000000000000000 c000000001730000 c000000000142558 0000000000000000
  GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000
  GPR24: c00000007be38a80 c000000000c002f4 0000000000000000 0000000000000000
  GPR28: c000000072221a00 c0000000726c2600 c00000007be38a80 c00000007be38a80
  NIP [c000000000097f88] __spin_yield+0x48/0xa0
  LR [c000000000c07a88] __raw_spin_lock+0xb8/0xc0
  Call Trace:
  [c000000072707c80] [c000000072221a00] 0xc000000072221a00 (unreliable)
  [c000000072707cb0] [c000000000bffb0c] __schedule+0xbc/0x850
  [c000000072707d70] [c000000000c002f4] schedule+0x54/0x130
  [c000000072707da0] [c0000000001427dc] kthreadd+0x28c/0x2b0
  [c000000072707e20] [c00000000000c1cc] ret_from_kernel_thread+0x5c/0x70
  Instruction dump:
  4d9e0020 552a043e 210a07ff 79080fe0 0b080000 3d020004 3908b878 794a1f24
  e8e80000 7ce7502a e8e70000 38e70100 <7ca03c2c> 70a70001 78a50020 4d820020
  ---[ end trace 474d6b2b8fc5cb7e ]---

Fixes: 499dcd4137 ("powerpc/64s: Allocate LPPACAs individually")
Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf>
[mpe: Reword change log a bit]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813031314.1828-4-cmr@informatik.wtf
2019-08-27 21:34:34 +10:00
Christopher M. Riedl
31391ff7ea powerpc/spinlocks: Rename SPLPAR-only spinlocks
The __rw_yield and __spin_yield locks only pertain to SPLPAR mode.
Rename them to make this relationship obvious.

Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813031314.1828-3-cmr@informatik.wtf
2019-08-27 13:03:36 +10:00
Christopher M. Riedl
d57b78353a powerpc/spinlocks: Refactor SHARED_PROCESSOR
Determining if a processor is in shared processor mode is not a constant
so don't hide it behind a #define.

Signed-off-by: Christopher M. Riedl <cmr@informatik.wtf>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813031314.1828-2-cmr@informatik.wtf
2019-08-27 13:03:36 +10:00
Christophe Leroy
d7fb5b18a5 powerpc/64: optimise LOAD_REG_IMMEDIATE_SYM()
Optimise LOAD_REG_IMMEDIATE_SYM() using a temporary register to
parallelise operations.

It reduces the path from 5 to 3 instructions.

Suggested-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/bad41ed02531bb0382420cbab50a0d7153b71767.1566311636.git.christophe.leroy@c-s.fr
2019-08-27 13:03:36 +10:00
Christophe Leroy
c691b4b83b powerpc: rewrite LOAD_REG_IMMEDIATE() as an intelligent macro
Today LOAD_REG_IMMEDIATE() is a basic #define which loads all
parts on a value into a register, including the parts that are NUL.

This means always 2 instructions on PPC32 and always 5 instructions
on PPC64. And those instructions cannot run in parallele as they are
updating the same register.

Ex: LOAD_REG_IMMEDIATE(r1,THREAD_SIZE) in head_64.S results in:

3c 20 00 00     lis     r1,0
60 21 00 00     ori     r1,r1,0
78 21 07 c6     rldicr  r1,r1,32,31
64 21 00 00     oris    r1,r1,0
60 21 40 00     ori     r1,r1,16384

Rewrite LOAD_REG_IMMEDIATE() with GAS macro in order to skip
the parts that are NUL.

Rename existing LOAD_REG_IMMEDIATE() as LOAD_REG_IMMEDIATE_SYM()
and use that one for loading value of symbols which are not known
at compile time.

Now LOAD_REG_IMMEDIATE(r1,THREAD_SIZE) in head_64.S results in:

38 20 40 00     li      r1,16384

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d60ce8dd3a383c7adbfc322bf1d53d81724a6000.1566311636.git.christophe.leroy@c-s.fr
2019-08-27 13:03:36 +10:00
Christophe Leroy
163918fc57 powerpc/mm: split out early ioremap path.
ioremap does things differently depending on whether
SLAB is available or not at different levels.

Try to separate the early path from the beginning.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3acd2dbe04b04f111475e7a59f2b6f2ab9b95ab6.1566309263.git.christophe.leroy@c-s.fr
2019-08-27 13:03:35 +10:00
Christophe Leroy
4a45b7460c powerpc/mm: refactor ioremap vm area setup.
PPC32 and PPC64 are doing the same once SLAB is available.
Create a do_ioremap() function that calls get_vm_area and
do the mapping.

For PPC64, we add the 4K PFN hack sanity check to __ioremap_caller()
in order to avoid using __ioremap_at(). Other checks in __ioremap_at()
are irrelevant for __ioremap_caller().

On PPC64, VM area is allocated in the range [ioremap_bot ; IOREMAP_END]
On PPC32, VM area is allocated in the range [VMALLOC_START ; VMALLOC_END]

Lets define IOREMAP_START is ioremap_bot for PPC64, and alias
IOREMAP_START/END to VMALLOC_START/END on PPC32

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/42e7e36ad32e0fdf76692426cc642799c9f689b8.1566309263.git.christophe.leroy@c-s.fr
2019-08-27 13:03:35 +10:00
Christophe Leroy
191e42063a powerpc/mm: refactor ioremap_range() and use ioremap_page_range()
book3s64's ioremap_range() is almost same as fallback ioremap_range(),
except that it calls radix__ioremap_range() when radix is enabled.

radix__ioremap_range() is also very similar to the other ones, expect
that it calls ioremap_page_range when slab is available.

PPC32 __ioremap_caller() have a loop doing the same thing as
ioremap_range() so use it on PPC32 as well.

Lets keep only one version of ioremap_range() which calls
ioremap_page_range() on all platforms when slab is available.

At the same time, drop the nid parameter which is not used.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4b1dca7096b01823b101be7338983578641547f1.1566309263.git.christophe.leroy@c-s.fr
2019-08-27 13:03:35 +10:00
Christophe Leroy
7cd9b317b6 powerpc/mm: make ioremap_bot common to all
Drop multiple definitions of ioremap_bot and make one common to
all subarches.

Only CONFIG_PPC_BOOK3E_64 had a global static init value for
ioremap_bot. Now ioremap_bot is set in early_init_mmu_global().

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/920eebfd9f36f14c79d1755847f5bf7c83703bdd.1566309262.git.christophe.leroy@c-s.fr
2019-08-27 13:03:34 +10:00
Christophe Leroy
14b4d97669 powerpc/mm: rework io-workaround invocation.
ppc_md.ioremap() is only used for I/O workaround on CELL platform,
so indirect function call can be avoided.

This patch reworks the io-workaround and ioremap() functions to
use the global 'io_workaround_inited' flag for the activation
of io-workaround.

When CONFIG_PPC_IO_WORKAROUNDS or CONFIG_PPC_INDIRECT_MMIO are not
selected, the I/O workaround ioremap() voids and the global flag is
not used.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5fa3ef069fbd0f152512afaae19e7a60161454cf.1566309262.git.christophe.leroy@c-s.fr
2019-08-27 13:03:34 +10:00
Christophe Leroy
492643e81e powerpc/mm: drop function __ioremap()
__ioremap() is not used anymore, drop it.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ccc439f481a0884e00a6be1bab44bab2a4477fea.1566309262.git.christophe.leroy@c-s.fr
2019-08-27 13:03:33 +10:00
Christophe Leroy
8aee077292 powerpc/mm: drop ppc_md.iounmap() and __iounmap()
ppc_md.iounmap() is never set, drop it.

Once ppc_md.iounmap() is gone, iounmap() remains the only user of
__iounmap() and iounmap() does nothing else than calling __iounmap().
So drop iounmap() and make __iounmap() the new iounmap().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/d73ba92bb7a387cc58cc34666d7f5158a45851b0.1566309262.git.christophe.leroy@c-s.fr
2019-08-27 13:03:33 +10:00
Christoph Hellwig
f0f8d7ae39 powerpc: remove the ppc44x ocm.c file
The on chip memory allocator is entirely unused in the kernel tree.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7b1668941ad1041d08b19167030868de5840b153.1566309262.git.christophe.leroy@c-s.fr
2019-08-27 13:03:33 +10:00
Paul Mackerras
2ad7a27dea KVM: PPC: Book3S: Enable XIVE native capability only if OPAL has required functions
There are some POWER9 machines where the OPAL firmware does not support
the OPAL_XIVE_GET_QUEUE_STATE and OPAL_XIVE_SET_QUEUE_STATE calls.
The impact of this is that a guest using XIVE natively will not be able
to be migrated successfully.  On the source side, the get_attr operation
on the KVM native device for the KVM_DEV_XIVE_GRP_EQ_CONFIG attribute
will fail; on the destination side, the set_attr operation for the same
attribute will fail.

This adds tests for the existence of the OPAL get/set queue state
functions, and if they are not supported, the XIVE-native KVM device
is not created and the KVM_CAP_PPC_IRQ_XIVE capability returns false.
Userspace can then either provide a software emulation of XIVE, or
else tell the guest that it does not have a XIVE controller available
to it.

Cc: stable@vger.kernel.org # v5.2+
Fixes: 3fab2d1058 ("KVM: PPC: Book3S HV: XIVE: Activate XIVE exploitation mode")
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-08-27 11:45:49 +10:00
Suraj Jitindar Singh
d22deab696 KVM: PPC: Book3S HV: Define usage types for rmap array in guest memslot
The rmap array in the guest memslot is an array of size number of guest
pages, allocated at memslot creation time. Each rmap entry in this array
is used to store information about the guest page to which it
corresponds. For example for a hpt guest it is used to store a lock bit,
rc bits, a present bit and the index of a hpt entry in the guest hpt
which maps this page. For a radix guest which is running nested guests
it is used to store a pointer to a linked list of nested rmap entries
which store the nested guest physical address which maps this guest
address and for which there is a pte in the shadow page table.

As there are currently two uses for the rmap array, and the potential
for this to expand to more in the future, define a type field (being the
top 8 bits of the rmap entry) to be used to define the type of the rmap
entry which is currently present and define two values for this field
for the two current uses of the rmap array.

Since the nested case uses the rmap entry to store a pointer, define
this type as having the two high bits set as is expected for a pointer.
Define the hpt entry type as having bit 56 set (bit 7 IBM bit ordering).

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-08-23 15:57:24 +10:00
Ingo Molnar
6c06b66e95 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU and LKMM changes from Paul E. McKenney:

 - A few more RCU flavor consolidation cleanups.

 - Miscellaneous fixes.

 - Updates to RCU's list-traversal macros improving lockdep usability.

 - Torture-test updates.

 - Forward-progress improvements for no-CBs CPUs: Avoid ignoring
   incoming callbacks during grace-period waits.

 - Forward-progress improvements for no-CBs CPUs: Use ->cblist
   structure to take advantage of others' grace periods.

 - Also added a small commit that avoids needlessly inflicting
   scheduler-clock ticks on callback-offloaded CPUs.

 - Forward-progress improvements for no-CBs CPUs: Reduce contention
   on ->nocb_lock guarding ->cblist.

 - Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass
   list to further reduce contention on ->nocb_lock guarding ->cblist.

 - LKMM updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-08-22 20:52:04 +02:00
Sam Bobroff
cef50c67c1 powerpc/eeh: Remove unused return path from eeh_pe_dev_traverse()
There are no users of the early-out return value from
eeh_pe_dev_traverse(), so remove it.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c648070f5b28fe8ca1880b48e64b267959ffd369.1565930772.git.sbobroff@linux.ibm.com
2019-08-22 23:12:47 +10:00
Sam Bobroff
1ff8f36fc7 powerpc/eeh: Convert log messages to eeh_edev_* macros
Convert existing messages, where appropriate, to use the eeh_edev_*
logging macros.

The only effect should be minor adjustments to the log messages, apart
from:

- A new message in pseries_eeh_probe() "Probing device" to match the
powernv case.
- The "Probing device" message in pnv_eeh_probe() is now generated
slightly later, which will mean that it is no longer emitted for
devices that aren't probed due to the initial checks.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ce505a0a7a4a5b0367f0f40f8b26e7c0a9cf4cb7.1565930772.git.sbobroff@linux.ibm.com
2019-08-22 23:12:47 +10:00
Sam Bobroff
b093f2cbed powerpc/eeh: Introduce EEH edev logging macros
Now that struct eeh_dev includes the BDFN of it's PCI device, make use
of it to replace eeh_edev_info() with a set of dev_dbg()-style macros
that only need a struct edev.

With the BDFN available without the struct pci_dev, eeh_pci_name() is
now unnecessary, so remove it.

While only the "info" level function is used here, the others will be
used in followup work.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f90ae9a53d762be7b0ccbad79e62b5a1b4f4996e.1565930772.git.sbobroff@linux.ibm.com
2019-08-22 23:12:46 +10:00
Oliver O'Halloran
7c33a994d3 powerpc/eeh: Add bdfn field to eeh_dev
Preparation for removing pci_dn from the powernv EEH code. The only
thing we really use pci_dn for is to get the bdfn of the device for
config space accesses, so adding that information to eeh_dev reduces
the need to carry around the pci_dn.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[SB: Re-wrapped commit message, fixed whitespace damage.]
Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/e458eb69a1f591d8a120782f23a8506b15d3c654.1565930772.git.sbobroff@linux.ibm.com
2019-08-22 23:12:46 +10:00
Sam Bobroff
c44e4ccada powerpc/eeh: Refactor around eeh_probe_devices()
Now that EEH support for all devices (on PowerNV and pSeries) is
provided by the pcibios bus add device hooks, eeh_probe_devices() and
eeh_addr_cache_build() are redundant and can be removed.

Move the EEH enabled message into it's own function so that it can be
called from multiple places.

Note that previously on pSeries, useless EEH sysfs files were created
for some devices that did not have EEH support and this change
prevents them from being created.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/33b0a6339d5ac88693de092d6fba984f2a5add66.1565930772.git.sbobroff@linux.ibm.com
2019-08-22 23:12:46 +10:00
Sam Bobroff
685a0bc00a powerpc/eeh: Initialize EEH address cache earlier
The EEH address cache is currently initialized and populated by a
single function: eeh_addr_cache_build().  While the initial population
of the cache can only be done once resources are allocated,
initialization (just setting up a spinlock) could be done much
earlier.

So move the initialization step into a separate function and call it
from a core_initcall (rather than a subsys initcall).

This will allow future work to make use of the cache during boot time
PCI scanning.

Signed-off-by: Sam Bobroff <sbobroff@linux.ibm.com>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0557206741bffee76cdfff042f65321f6f7a5b41.1565930772.git.sbobroff@linux.ibm.com
2019-08-22 23:11:48 +10:00
Santosh Sivaraj
42ac26d253 powerpc: add machine check safe copy_to_user
Use  memcpy_mcsafe() implementation to define copy_to_user_mcsafe()

Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-8-santosh@fossix.org
2019-08-21 22:23:49 +10:00
Balbir Singh
4d4a273854 powerpc/memcpy: Add memcpy_mcsafe for pmem
The pmem infrastructure uses memcpy_mcsafe in the pmem layer so as to
convert machine check exceptions into a return value on failure in case
a machine check exception is encountered during the memcpy. The return
value is the number of bytes remaining to be copied.

This patch largely borrows from the copyuser_power7 logic and does not add
the VMX optimizations, largely to keep the patch simple. If needed those
optimizations can be folded in.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[arbab@linux.ibm.com: Added symbol export]
Co-developed-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-7-santosh@fossix.org
2019-08-21 22:23:48 +10:00
Balbir Singh
895e3dceeb powerpc/mce: Handle UE event for memcpy_mcsafe
If we take a UE on one of the instructions with a fixup entry, set nip
to continue execution at the fixup entry. Stop processing the event
further or print it.

Co-developed-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-6-santosh@fossix.org
2019-08-21 22:23:48 +10:00
Nicholas Piggin
6bb25170d7 powerpc/64s/radix: Remove redundant pfn_pte bitop, add VM_BUG_ON
pfn_pte is never given a pte above the addressable physical memory
limit, so the masking is redundant. In case of a software bug, it
is not obviously better to silently truncate the pfn than to corrupt
the pte (either one will result in memory corruption or crashes),
so there is no reason to add this to the fast path.

Add VM_BUG_ON to catch cases where the pfn is invalid. These would
catch the create_section_mapping bug fixed by a previous commit.

  [16885.256466] ------------[ cut here ]------------
  [16885.256492] kernel BUG at arch/powerpc/include/asm/book3s/64/pgtable.h:612!
  cpu 0x0: Vector: 700 (Program Check) at [c0000000ee0a36d0]
      pc: c000000000080738: __map_kernel_page+0x248/0x6f0
      lr: c000000000080ac0: __map_kernel_page+0x5d0/0x6f0
      sp: c0000000ee0a3960
     msr: 9000000000029033
    current = 0xc0000000ec63b400
    paca    = 0xc0000000017f0000   irqmask: 0x03   irq_happened: 0x01
      pid   = 85, comm = sh
  kernel BUG at arch/powerpc/include/asm/book3s/64/pgtable.h:612!
  Linux version 5.3.0-rc1-00001-g0fe93e5f3394
  enter ? for help
  [c0000000ee0a3a00] c000000000d37378 create_physical_mapping+0x260/0x360
  [c0000000ee0a3b10] c000000000d370bc create_section_mapping+0x1c/0x3c
  [c0000000ee0a3b30] c000000000071f54 arch_add_memory+0x74/0x130

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190724084638.24982-5-npiggin@gmail.com
2019-08-20 21:22:20 +10:00
Nicholas Piggin
4dd7554a64 powerpc/64: Add VIRTUAL_BUG_ON checks for __va and __pa addresses
Ensure __va is given a physical address below PAGE_OFFSET, and __pa is
given a virtual address above PAGE_OFFSET.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190724084638.24982-4-npiggin@gmail.com
2019-08-20 21:22:20 +10:00
Nicholas Piggin
e354d7dc81 powerpc/64: allow compiler to cache 'current'
current may be cached by the compiler, so remove the volatile asm
restriction. This results in better generated code, as well as being
smaller and fewer dependent loads, it can avoid store-hit-load flushes
like this one that shows up in irq_exit():

    preempt_count_sub(HARDIRQ_OFFSET);
    if (!in_interrupt() && ...)

Which ends up as:

    ((struct thread_info *)current)->preempt_count -= HARDIRQ_OFFSET;
    if (((struct thread_info *)current)->preempt_count ...

Evaluating current twice presently means it has to be loaded twice, and
here gcc happens to pick a different register each time, then
preempt_count is accessed via that base register:

    1058:       ld      r10,2392(r13)     <-- current
    105c:       lwz     r9,0(r10)         <-- preempt_count
    1060:       addis   r9,r9,-1
    1064:       stw     r9,0(r10)         <-- preempt_count
    1068:       ld      r9,2392(r13)      <-- current
    106c:       lwz     r9,0(r9)          <-- preempt_count
    1070:       rlwinm. r9,r9,0,11,23
    1074:       bne     1090 <irq_exit+0x60>

This can frustrate store-hit-load detection heuristics and cause
flushes. Allowing the compiler to cache current in a reigster with this
patch results in the same base register being used for all accesses,
which is more likely to be detected as an alias:

    1058:       ld      r31,2392(r13)
    ...
    1070:       lwz     r9,0(r31)
    1074:       addis   r9,r9,-1
    1078:       stw     r9,0(r31)
    107c:       lwz     r9,0(r31)
    1080:       rlwinm. r9,r9,0,11,23
    1084:       bne     10a0 <irq_exit+0x60>

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190612140317.24490-1-npiggin@gmail.com
2019-08-20 21:22:15 +10:00
Christophe Leroy
7ab0b7cb89 powerpc/32: Add warning on misaligned copy_page() or clear_page()
copy_page() and clear_page() expect page aligned destination, and
use dcbz instruction to clear entire cache lines based on the
assumption that the destination is cache aligned.

As shown during analysis of a bug in BTRFS filesystem, a misaligned
copy_page() can create bugs that are difficult to locate (see Link).

Add an explicit WARNING when copy_page() or clear_page() are called
with misaligned destination.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=204371
Link: https://lore.kernel.org/r/c6cea38f90480268d439ca44a645647e260fff09.1565941808.git.christophe.leroy@c-s.fr
2019-08-20 21:22:15 +10:00
Christophe Leroy
4c1616ef03 powerpc/mm: move FSL_BOOK3 version of update_mmu_cache()
Move FSL_BOOK3E version of update_mmu_cache() at the same
place as book3e_hugetlb_preload() as update_mmu_cache() is
the only user of book3e_hugetlb_preload().

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/4d69fdc86df9c74adc71a60331a86f6afb8b5e9e.1565933217.git.christophe.leroy@c-s.fr
2019-08-20 21:22:14 +10:00
Christophe Leroy
d964211791 powerpc/mm: define empty update_mmu_cache() as static inline
Only BOOK3S and FSL_BOOK3E have a usefull update_mmu_cache().

For the others, just define it static inline.

In the meantime, simplify the FSL_BOOK3E related ifdef as
book3e_hugetlb_preload() only exists when CONFIG_PPC_FSL_BOOK3E
is selected.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/668aba4db6b9af6d8a151174e11a4289f1a6bbcd.1565933217.git.christophe.leroy@c-s.fr
2019-08-20 21:22:14 +10:00
Christophe Leroy
38a0d0cdb4 powerpc/futex: Fix warning: 'oldval' may be used uninitialized in this function
We see warnings such as:
  kernel/futex.c: In function 'do_futex':
  kernel/futex.c:1676:17: warning: 'oldval' may be used uninitialized in this function [-Wmaybe-uninitialized]
     return oldval == cmparg;
                   ^
  kernel/futex.c:1651:6: note: 'oldval' was declared here
    int oldval, ret;
        ^

This is because arch_futex_atomic_op_inuser() only sets *oval if ret
is 0 and GCC doesn't see that it will only use it when ret is 0.

Anyway, the non-zero ret path is an error path that won't suffer from
setting *oval, and as *oval is a local var in futex_atomic_op_inuser()
it will have no impact.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: reword change log slightly]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/86b72f0c134367b214910b27b9a6dd3321af93bb.1565774657.git.christophe.leroy@c-s.fr
2019-08-20 21:22:12 +10:00
Christophe Leroy
65e701b2d2 powerpc/ptdump: drop non vital #ifdefs
hashpagetable.c is only compiled when CONFIG_PPC_BOOK3S_64 is
defined, so drop the test and its 'else' branch.

Use IS_ENABLED(CONFIG_PPC_PSERIES) instead of #ifdef, this allows the
code to be checked at any build. It is still optimised out by GCC.

Use IS_ENABLED(CONFIG_PPC_64K_PAGES) instead of #ifdef.

Use IS_ENABLED(CONFIG_SPARSEMEN_VMEMMAP) instead of #ifdef.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c8998ed32e4e3954b56a8dacecfe43319a2a0483.1565786091.git.christophe.leroy@c-s.fr
2019-08-20 21:22:09 +10:00
Cédric Le Goater
b4868ff55d powerpc/xive: Fix dump of XIVE interrupt under pseries
The xmon 'dxi' command calls OPAL to query the XIVE configuration of a
interrupt. This can only be done on baremetal (PowerNV) and it will
crash a pseries machine.

Introduce a new XIVE get_irq_config() operation which implements a
different query depending on the platform, PowerNV or pseries, and
modify xmon to use a top level wrapper.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190814154754.23682-3-clg@kaod.org
2019-08-19 13:20:24 +10:00
Alexey Kardashevskiy
201ed7f327 powerpc/powernv/ioda2: Create bigger default window with 64k IOMMU pages
At the moment we create a small window only for 32bit devices, the window
maps 0..2GB of the PCI space only. For other devices we either use
a sketchy bypass or hardware bypass but the former can only work if
the amount of RAM is no bigger than the device's DMA mask and the latter
requires devices to support at least 59bit DMA.

This extends the default DMA window to the maximum size possible to allow
a wider DMA mask than just 32bit. The default window size is now limited
by the the iommu_table::it_map allocation bitmap which is a contiguous
array, 1 bit per an IOMMU page.

This increases the default IOMMU page size from hard coded 4K to
the system page size to allow wider DMA masks.

This increases the level number to not exceed the max order allocation
limit per TCE level. By the same time, this keeps minimal levels number
as 2 in order to save memory.

As the extended window now overlaps the 32bit MMIO region, this adds
an area reservation to iommu_init_table().

After this change the default window size is 0x80000000000==1<<43 so
devices limited to DMA mask smaller than the amount of system RAM can
still use more than just 2GB of memory for DMA.

This is an optimization and not a bug fix for DMA API usage.

With the on-demand allocation of indirect TCE table levels enabled and
2 levels, the first TCE level size is just
1<<ceil((log2(0x7ffffffffff+1)-16)/2)=16384 TCEs or 2 system pages.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190718051139.74787-5-aik@ozlabs.ru
2019-08-19 13:20:23 +10:00
Michael Ellerman
1a47908e0f Merge branch 'topic/ppc-kvm' into next
Merge our ppc-kvm topic branch. This contains several fixes for the XIVE
interrupt controller that we are sharing with the KVM tree.
2019-08-19 13:19:43 +10:00
Michael Ellerman
4215fa2d7d Merge branch 'fixes' into next
Merge in our fixes branch, which brings in clone3() as well as some
implicit fallthrough fixes we want in next.
2019-08-19 12:43:13 +10:00
Paul Mackerras
da15c03b04 powerpc/xive: Implement get_irqchip_state method for XIVE to fix shutdown race
Testing has revealed the existence of a race condition where a XIVE
interrupt being shut down can be in one of the XIVE interrupt queues
(of which there are up to 8 per CPU, one for each priority) at the
point where free_irq() is called.  If this happens, can return an
interrupt number which has been shut down.  This can lead to various
symptoms:

- irq_to_desc(irq) can be NULL.  In this case, no end-of-interrupt
  function gets called, resulting in the CPU's elevated interrupt
  priority (numerically lowered CPPR) never gets reset.  That then
  means that the CPU stops processing interrupts, causing device
  timeouts and other errors in various device drivers.

- The irq descriptor or related data structures can be in the process
  of being freed as the interrupt code is using them.  This typically
  leads to crashes due to bad pointer dereferences.

This race is basically what commit 62e0468650 ("genirq: Add optional
hardware synchronization for shutdown", 2019-06-28) is intended to
fix, given a get_irqchip_state() method for the interrupt controller
being used.  It works by polling the interrupt controller when an
interrupt is being freed until the controller says it is not pending.

With XIVE, the PQ bits of the interrupt source indicate the state of
the interrupt source, and in particular the P bit goes from 0 to 1 at
the point where the hardware writes an entry into the interrupt queue
that this interrupt is directed towards.  Normally, the code will then
process the interrupt and do an end-of-interrupt (EOI) operation which
will reset PQ to 00 (assuming another interrupt hasn't been generated
in the meantime).  However, there are situations where the code resets
P even though a queue entry exists (for example, by setting PQ to 01,
which disables the interrupt source), and also situations where the
code leaves P at 1 after removing the queue entry (for example, this
is done for escalation interrupts so they cannot fire again until
they are explicitly re-enabled).

The code already has a 'saved_p' flag for the interrupt source which
indicates that a queue entry exists, although it isn't maintained
consistently.  This patch adds a 'stale_p' flag to indicate that
P has been left at 1 after processing a queue entry, and adds code
to set and clear saved_p and stale_p as necessary to maintain a
consistent indication of whether a queue entry may or may not exist.

With this, we can implement xive_get_irqchip_state() by looking at
stale_p, saved_p and the ESB PQ bits for the interrupt.

There is some additional code to handle escalation interrupts
properly; because they are enabled and disabled in KVM assembly code,
which does not have access to the xive_irq_data struct for the
escalation interrupt.  Hence, stale_p may be incorrect when the
escalation interrupt is freed in kvmppc_xive_{,native_}cleanup_vcpu().
Fortunately, we can fix it up by looking at vcpu->arch.xive_esc_on,
with some careful attention to barriers in order to ensure the correct
result if xive_esc_irq() races with kvmppc_xive_cleanup_vcpu().

Finally, this adds code to make noise on the console (pr_crit and
WARN_ON(1)) if we find an interrupt queue entry for an interrupt
which does not have a descriptor.  While this won't catch the race
reliably, if it does get triggered it will be an indication that
the race is occurring and needs to be debugged.

Fixes: 243e25112d ("powerpc/xive: Native exploitation of the XIVE interrupt controller")
Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190813100648.GE9567@blackberry
2019-08-16 14:16:59 +10:00
Denis Efremov
b8074aa246 PCI: Convert pci_resource_to_user() to a weak function
Convert pci_resource_to_user() to a weak function so the existing
architecture-specific implementations will automatically override the
generic one.  This allows us to remove HAVE_ARCH_PCI_RESOURCE_TO_USER
definitions and avoid the conditional compilation for this single function.

Link: https://lore.kernel.org/r/20190729101401.28068-1-efremov@linux.com
Link: https://lore.kernel.org/r/20190729101401.28068-2-efremov@linux.com
Link: https://lore.kernel.org/r/20190729101401.28068-3-efremov@linux.com
Link: https://lore.kernel.org/r/20190729101401.28068-4-efremov@linux.com
Link: https://lore.kernel.org/r/20190729101401.28068-5-efremov@linux.com
Link: https://lore.kernel.org/r/20190729101401.28068-6-efremov@linux.com
Signed-off-by: Denis Efremov <efremov@linux.com>
[bhelgaas: squash into one commit]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Paul Burton <paul.burton@mips.com>	# MIPS
2019-08-08 15:12:07 -05:00
Leo Yan
45880f7b7b error-injection: Consolidate override function definition
The function override_function_with_return() is defined separately for
each architecture and every architecture's definition is almost same
with each other.  E.g. x86 and powerpc both define function in its own
asm/error-injection.h header and override_function_with_return() has
the same definition, the only difference is that x86 defines an extra
function just_return_func() but it is specific for x86 and is only used
by x86's override_function_with_return(), so don't need to export this
function.

This patch consolidates override_function_with_return() definition into
asm-generic/error-injection.h header, thus all architectures can use the
common definition.  As result, the architecture specific headers are
removed; the include/linux/error-injection.h header also changes to
include asm-generic/error-injection.h header rather than architecture
header, furthermore, it includes linux/compiler.h for successful
compilation.

Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-07 13:52:43 +01:00
Andrew Donnellan
08a456aa64 powerpc/powernv: Move SCOM access code into powernv platform
The powernv platform is the only one that directly accesses SCOMs.
Move the support code to platforms/powernv, and get rid of the
PPC_SCOM Kconfig option, as SCOM support is always selected when
compiling for powernv.

This also means that the Kconfig item for CONFIG_SCOM_DEBUGFS will
show up in menuconfig in the platform menu, rather than at the root,
which is a much better location.

Signed-off-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190509051119.7694-1-ajd@linux.ibm.com
2019-08-05 18:53:03 +10:00
Herbert Xu
155e4db324 asm-generic: Remove redundant arch-specific rules for simd.h
Now that simd.h is in include/asm-generic/Kbuild we don't need
the arch-specific Kbuild rules for them.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 82cb548568 ("asm-generic: make simd.h a mandatory...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2019-08-02 14:45:15 +10:00
Joel Fernandes (Google)
0a5b99f578 treewide: Rename rcu_dereference_raw_notrace() to _check()
The rcu_dereference_raw_notrace() API name is confusing.  It is equivalent
to rcu_dereference_raw() except that it also does sparse pointer checking.

There are only a few users of rcu_dereference_raw_notrace(). This patches
renames all of them to be rcu_dereference_raw_check() with the "_check()"
indicating sparse checking.

Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Fix checkpatch warnings about parentheses. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-08-01 14:16:21 -07:00
Michael Ellerman
ed4289e8b4 Revert "powerpc: slightly improve cache helpers"
This reverts commit 6c5875843b.

It triggers a probable compiler bug on clang which leads to crashes.

With GCC it allows the compiler to use a more efficient register
allocation but current GCC versions never do that at any of the current
call sites, so there's no benefit.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-31 22:56:27 +10:00
Michael Ellerman
cee3536d24 powerpc: Wire up clone3 syscall
Wire up the new clone3 syscall added in commit 7f192e3cd3 ("fork:
add clone3").

This requires a ppc_clone3 wrapper, in order to save the non-volatile
GPRs before calling into the generic syscall code. Otherwise we hit
the BUG_ON in CHECK_FULL_REGS in copy_thread().

Lightly tested using Christian's test code on a Power8 LE VM.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Christian Brauner <christian@brauner.io>
Link: https://lore.kernel.org/r/20190724140259.23554-1-mpe@ellerman.id.au
2019-07-29 09:34:27 +10:00
Linus Torvalds
bed38c3e2d powerpc fixes for 5.3 #2
An assortment of non-regression fixes that have accumulated since the start of
 the merge window.
 
 A fix for a user triggerable oops on machines where transactional memory is
 disabled, eg. Power9 bare metal, Power8 with TM disabled on the command line, or
 all Power7 or earlier machines.
 
 Three fixes for handling of PMU and power saving registers when running nested
 KVM on Power9.
 
 Two fixes for bugs found while stress testing the XIVE interrupt controller
 code, also on Power9.
 
 A fix to allow guests to boot under Qemu/KVM on Power9 using the the Hash MMU
 with >= 1TB of memory.
 
 Two fixes for bugs in the recent DMA cleanup, one of which could lead to
 checkstops.
 
 And finally three fixes for the PAPR SCM nvdimm driver.
 
 Thanks to:
   Alexey Kardashevskiy, Andrea Arcangeli, Cédric Le Goater, Christoph Hellwig,
   David Gibson, Gautham R. Shenoy, Michael Neuling, Oliver O'Halloran,, Satheesh
   Rajendran, Shawn Anastasio, Suraj Jitindar Singh, Vaibhav Jain.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJdOF2iAAoJEFHr6jzI4aWAVmsQAJ//UY1a+lz39y/5jmkybJbH
 HVnja6ZhsKd3+ZAnljGmqr1zuwDmy8+X3pT+1832zBBm4Z1cNKj1c0wuK5fuhAfq
 o0XkO0N9GFcQu8HUPb5wSBOoyXwK0qUhExfCVobl7YsDAyAI2//nSQTwxNX3W4Hv
 P7hz48pBbiqRzQAOSHV8ZlcOBETbSVAXeNalSXrXqSJmXQbVWCQcd6vucMSwZ7S5
 ZiiL/gCBoO0kd0ZQRsGXCbwcjcR4NlTDN0M40og8Y9KTDkId8HdmJyXW3tMcZo/g
 W3LeMR94bUh/KrK88lMBrRXKUlxL+loZKWZaeNlA5+ShCYk/ZafkKri/QUX/glOq
 ahm8uqokdZ5VS1tgSYoJIKdA5qMGvv8V+CpHRJnZqaEhUCduQa5XmWPnDnEKkDt0
 94VBsk0D2vHYKyygv5JMgYHQVlU7XrQF8fw2pKShpqLMY7ZMpeDDmKN9AuzxhawF
 9b7HigbwNt5LvNJ0xn097KW+svCK7i3ZgiQe83W36wjSl2ystgjJ3T7yrH6Q1rKH
 o4loEGA4gASTDjTmWQM20lHT1xQHY4fQBC/wi/67as3m0TDeGXYI0fOZC5qtEBFr
 Ln/0e78VMhut/RWicDlRveszef1MCi1warR9R4I/bQ8M6O1BzHYsQ9zr6H111uxL
 vQ92Yp8G2PoqN7wlFlSG
 =Yc9T
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "An assortment of non-regression fixes that have accumulated since the
  start of the merge window.

   - A fix for a user triggerable oops on machines where transactional
     memory is disabled, eg. Power9 bare metal, Power8 with TM disabled
     on the command line, or all Power7 or earlier machines.

   - Three fixes for handling of PMU and power saving registers when
     running nested KVM on Power9.

   - Two fixes for bugs found while stress testing the XIVE interrupt
     controller code, also on Power9.

   - A fix to allow guests to boot under Qemu/KVM on Power9 using the
     the Hash MMU with >= 1TB of memory.

   - Two fixes for bugs in the recent DMA cleanup, one of which could
     lead to checkstops.

   - And finally three fixes for the PAPR SCM nvdimm driver.

  Thanks to: Alexey Kardashevskiy, Andrea Arcangeli, Cédric Le Goater,
  Christoph Hellwig, David Gibson, Gautham R. Shenoy, Michael Neuling,
  Oliver O'Halloran, Satheesh Rajendran, Shawn Anastasio, Suraj Jitindar
  Singh, Vaibhav Jain"

* tag 'powerpc-5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/papr_scm: Force a scm-unbind if initial scm-bind fails
  powerpc/papr_scm: Update drc_pmem_unbind() to use H_SCM_UNBIND_ALL
  powerpc/pseries: Update SCM hcall op-codes in hvcall.h
  powerpc/tm: Fix oops on sigreturn on systems without TM
  powerpc/dma: Fix invalid DMA mmap behavior
  KVM: PPC: Book3S HV: XIVE: fix rollback when kvmppc_xive_create fails
  powerpc/xive: Fix loop exit-condition in xive_find_target_in_mask()
  powerpc: fix off by one in max_zone_pfn initialization for ZONE_DMA
  KVM: PPC: Book3S HV: Save and restore guest visible PSSCR bits on pseries
  powerpc/pmu: Set pmcregs_in_use in paca when running as LPAR
  KVM: PPC: Book3S HV: Always save guest pmu for guest capable of nesting
  powerpc/mm: Limit rma_size to 1TB when running without HV mode
2019-07-24 09:58:39 -07:00
Vaibhav Jain
6d140e7569 powerpc/pseries: Update SCM hcall op-codes in hvcall.h
Update the hvcalls.h to include op-codes for new hcalls introduce to
manage SCM memory. Also update existing hcall definitions to reflect
current papr specification for SCM.

The removed hcall op-codes H_SCM_MEM_QUERY, H_SCM_BLOCK_CLEAR were
transient proposals and there support was never implemented by
Power-VM nor they were used anywhere in Linux kernel. Hence we don't
expect anyone to be impacted by this change.

Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190629160610.23402-2-vaibhav@linux.ibm.com
2019-07-22 23:31:00 +10:00
Robin Murphy
175967318c mm: introduce ARCH_HAS_PTE_DEVMAP
ARCH_HAS_ZONE_DEVICE is somewhat meaningless in itself, and combined
with the long-out-of-date comment can lead to the impression than an
architecture may just enable it (since __add_pages() now "comprehends
device memory" for itself) and expect things to work.

In practice, however, ZONE_DEVICE users have little chance of
functioning correctly without __HAVE_ARCH_PTE_DEVMAP, so let's clean
that up the same way as ARCH_HAS_PTE_SPECIAL and make it the proper
dependency so the real situation is clearer.

Link: http://lkml.kernel.org/r/87554aa78478a02a63f2c4cf60a847279ae3eb3b.1558547956.git.robin.murphy@arm.com
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16 19:23:25 -07:00
Dmitry V. Levin
f296f1df6e powerpc: define syscall_get_error()
syscall_get_error() is required to be implemented on this architecture in
addition to already implemented syscall_get_nr(), syscall_get_arguments(),
syscall_get_return_value(), and syscall_get_arch() functions in order to
extend the generic ptrace API with PTRACE_GET_SYSCALL_INFO request.

Link: http://lkml.kernel.org/r/20190510152824.GE28558@altlinux.org
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Elvira Khabirova <lineprinter@altlinux.org>
Cc: Eugene Syromyatnikov <esyr@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Helge Deller <deller@gmx.de>	[parisc]
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: kbuild test robot <lkp@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vincent Chen <deanbo422@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16 19:23:24 -07:00