Commit Graph

2458 Commits

Author SHA1 Message Date
Aneesh Kumar K.V
269e829f48 powerpc/book3s64/pkey: Disable pkey on POWER6 and before
POWER6 only supports AMR update via privileged mode (MSR[PR] = 0,
SPRN_AMR=29) The PR=1 (userspace) alias for that SPR (SPRN_AMR=13) was
only supported from POWER7. Since we don't allow userspace modifying
of AMR value we should disable pkey support on P6 and before.

The hypervisor will still report pkey support via
"ibm,processor-storage-keys". Hence also check for P7 CPU_FTR bit to
decide on pkey support.

Fixes: f491fe3fb4 ("powerpc/book3s64/pkeys: Simplify the key initialization")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-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/20200726132517.399076-1-aneesh.kumar@linux.ibm.com
2020-07-26 23:34:18 +10:00
Santosh Sivaraj
69507b984d powerpc/mm/hash64: Remove comment that is no longer valid
hash_low_64.S was removed in commit a43c0eb836 ("powerpc/mm: Convert
4k insert from asm to C") and flush_hash_page() is no longer called
from any assembly routine.

Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
[mpe: Tweak comment wording]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200721091915.205006-1-santosh@fossix.org
2020-07-23 17:43:35 +10:00
Nicholas Piggin
5c9fa16e8a powerpc/64s: Remove PROT_SAO support
ISA v3.1 does not support the SAO storage control attribute required to
implement PROT_SAO. PROT_SAO was used by specialised system software
(Lx86) that has been discontinued for about 7 years, and is not thought
to be used elsewhere, so removal should not cause problems.

We rather remove it than keep support for older processors, because
live migrating guest partitions to newer processors may not be possible
if SAO is in use (or worse allowed with silent races).

- PROT_SAO stays in the uapi header so code using it would still build.
- arch_validate_prot() is removed, the generic version rejects PROT_SAO
  so applications would get a failure at mmap() time.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop KVM change for the time being]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200703011958.1166620-3-npiggin@gmail.com
2020-07-22 00:01:25 +10:00
Aneesh Kumar K.V
482b9b3948 powerpc/book3s64/pkeys: Remove is_pkey_enabled()
There is only one caller to this function and the function is wrongly
named. Avoid further confusion w.r.t name and open code this at the
only call site. Also remove read_uamor(). There are no users for
the same after this.

Signed-off-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/20200709032946.881753-24-aneesh.kumar@linux.ibm.com
2020-07-22 00:01:22 +10:00
Aneesh Kumar K.V
e0d8e991be powerpc/book3s64/kuap: Move UAMOR setup to key init function
UAMOR values are not application-specific. The kernel initializes
its value based on different reserved keys. Remove the thread-specific
UAMOR value and don't switch the UAMOR on context switch.

Move UAMOR initialization to key initialization code and remove
thread_struct.uamor because it is not used anymore.

Before commit: 4a4a5e5d2a ("powerpc/pkeys: key allocation/deallocation must not change pkey registers")
we used to update uamor based on key allocation and free.

Signed-off-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/20200709032946.881753-20-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:59 +10:00
Aneesh Kumar K.V
000a42b35a powerpc/book3s64/keys/kuap: Reset AMR/IAMR values on kexec
As we kexec across kernels that use AMR/IAMR for different purposes
we need to ensure that new kernels get kexec'd with a reset value
of AMR/IAMR. For ex: the new kernel can use key 0 for kernel mapping and the old
AMR value prevents access to key 0.

This patch also removes reset if IAMR and AMOR in kexec_sequence. Reset of AMOR
is not needed and the IAMR reset is partial (it doesn't do the reset
on secondary cpus) and is redundant with this patch.

Signed-off-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/20200709032946.881753-19-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:59 +10:00
Aneesh Kumar K.V
7cdd3745f2 powerpc/book3s64/keys: Print information during boot.
Signed-off-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/20200709032946.881753-18-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:59 +10:00
Aneesh Kumar K.V
f7045a4511 powerpc/book3s64/pkeys: Use MMU_FTR_PKEY instead of pkey_disabled static key
Instead of pkey_disabled static key use mmu feature MMU_FTR_PKEY.

Signed-off-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/20200709032946.881753-17-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:59 +10:00
Aneesh Kumar K.V
2daf298de7 powerpc/book3s64/pkeys: Use pkey_execute_disable_supported
Use pkey_execute_disable_supported to check for execute key support instead
of pkey_disabled.

Signed-off-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/20200709032946.881753-16-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:59 +10:00
Aneesh Kumar K.V
e10cc8715d powerpc/book3s64/kuep: Add MMU_FTR_KUEP
This will be used to enable/disable Kernel Userspace Execution
Prevention (KUEP).

Signed-off-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/20200709032946.881753-15-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:58 +10:00
Aneesh Kumar K.V
d3cd91fb8d powerpc/book3s64/pkeys: Add MMU_FTR_PKEY
Parse storage keys related device tree entry in early_init_devtree
and enable MMU feature MMU_FTR_PKEY if pkeys are supported.

MMU feature is used instead of CPU feature because this enables us
to group MMU_FTR_KUAP and MMU_FTR_PKEY in asm feature fixup code.

Signed-off-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/20200709032946.881753-14-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:58 +10:00
Aneesh Kumar K.V
3e4352aeb8 powerpc/book3s64/pkeys: Mark all the pkeys above max pkey as reserved
The hypervisor can return less than max allowed pkey (for ex: 31) instead
of 32. We should mark all the pkeys above max allowed as reserved so
that we avoid the allocation of the wrong pkey(for ex: key 31 in the above
case) by userspace.

Signed-off-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/20200709032946.881753-13-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:58 +10:00
Aneesh Kumar K.V
3c8ab47362 powerpc/book3s64/pkeys: Make initial_allocation_mask static
initial_allocation_mask is not used outside this file.
Also mark reserved_allocation_mask and initial_allocation_mask __ro_after_init;

Signed-off-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/20200709032946.881753-12-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:58 +10:00
Aneesh Kumar K.V
c529afd7cb powerpc/book3s64/pkeys: Convert pkey_total to num_pkey
num_pkey now represents max number of keys supported such that we return
to userspace 0 - num_pkey - 1.

Signed-off-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/20200709032946.881753-11-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:58 +10:00
Aneesh Kumar K.V
a4678d4b47 powerpc/book3s64/pkeys: Simplify pkey disable branch
Make the default value FALSE (pkey enabled) and set to TRUE when we
find the total number of keys supported to be zero.

Signed-off-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/20200709032946.881753-10-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:58 +10:00
Aneesh Kumar K.V
718d9b3801 powerpc/book3s64/pkeys: Prevent key 1 modification from userspace.
Key 1 is marked reserved by ISA. Setup uamor to prevent userspace modification
of the same.

Signed-off-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/20200709032946.881753-8-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:58 +10:00
Aneesh Kumar K.V
f491fe3fb4 powerpc/book3s64/pkeys: Simplify the key initialization
Add documentation explaining the execute_only_key. The reservation and initialization mask
details are also explained in this patch.

No functional change in this patch.

Signed-off-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/20200709032946.881753-7-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:57 +10:00
Aneesh Kumar K.V
1f404058e2 powerpc/book3s64/pkeys: Explain key 1 reservation details
This explains the details w.r.t key 1.

Signed-off-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/20200709032946.881753-6-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:57 +10:00
Aneesh Kumar K.V
d79e7a5f26 powerpc/book3s64/pkeys: Use PVR check instead of cpu feature
We are wrongly using CPU_FTRS_POWER8 to check for P8 support. Instead, we should
use PVR value. Now considering we are using CPU_FTRS_POWER8, that
implies we returned true for P9 with older firmware. Keep the same behavior
by checking for P9 PVR value.

Fixes: cf43d3b264 ("powerpc: Enable pkey subsystem")
Signed-off-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/20200709032946.881753-2-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:57 +10:00
Aneesh Kumar K.V
af9d00e93a powerpc/mm/radix: Create separate mappings for hot-plugged memory
To enable memory unplug without splitting kernel page table
mapping, we force the max mapping size to the LMB size. LMB
size is the unit in which hypervisor will do memory add/remove
operation.

Pseries systems supports max LMB size of 256MB. Hence on pseries,
we now end up mapping memory with 2M page size instead of 1G. To improve
that we want hypervisor to hint the kernel about the hotplug
memory range. That was added that as part of

commit b6eca183e2 ("powerpc/kernel: Enables memory
hot-remove after reboot on pseries guests")

But PowerVM doesn't provide that hint yet. Once we get PowerVM
updated, we can then force the 2M mapping only to hot-pluggable
memory region using memblock_is_hotpluggable(). Till then
let's depend on LMB size for finding the mapping page size
for linear range.

With this change KVM guest will also be doing linear mapping with
2M page size.

The actual TLB benefit of mapping guest page table entries with
hugepage size can only be materialized if the partition scoped
entries are also using the same or higher page size. A guest using
1G hugetlbfs backing guest memory can have a performance impact with
the above change.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Fold in fix from Aneesh spotted by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200709131925.922266-5-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:56 +10:00
Bharata B Rao
d6d6ebfc5d powerpc/mm/radix: Remove split_kernel_mapping()
We split the page table mapping on memory unplug if the
linear range was mapped with huge page mapping (for ex: 1G)
The page table splitting code has a few issues:

1. Recursive locking
--------------------
Memory unplug path takes cpu_hotplug_lock and calls stop_machine()
for splitting the mappings. However stop_machine() takes
cpu_hotplug_lock again causing deadlock.

2. BUG: sleeping function called from in_atomic() context
---------------------------------------------------------
Memory unplug path (remove_pagetable) takes init_mm.page_table_lock
spinlock and later calls stop_machine() which does wait_for_completion()

3. Bad unlock unbalance
-----------------------
Memory unplug path takes init_mm.page_table_lock spinlock and calls
stop_machine(). The stop_machine thread function runs in a different
thread context (migration thread) which tries to release and reaquire
ptl. Releasing ptl from a different thread than which acquired it
causes bad unlock unbalance.

These problems can be avoided if we avoid mapping hot-plugged memory
with 1G mapping, thereby removing the need for splitting them during
unplug. The kernel always make sure the minimum unplug request is
SUBSECTION_SIZE for device memory and SECTION_SIZE for regular memory.

In preparation for such a change remove page table splitting support.

This essentially is a revert of
commit 4dd5f8a99e ("powerpc/mm/radix: Split linear mapping on hot-unplug")

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-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/20200709131925.922266-4-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:56 +10:00
Bharata B Rao
9ce8853b4a powerpc/mm/radix: Free PUD table when freeing pagetable
remove_pagetable() isn't freeing PUD table. This causes memory
leak during memory unplug. Fix this.

Fixes: 4b5d62ca17 ("powerpc/mm: add radix__remove_section_mapping()")
Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-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/20200709131925.922266-3-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:56 +10:00
Aneesh Kumar K.V
645d5ce2f7 powerpc/mm/radix: Fix PTE/PMD fragment count for early page table mappings
We can hit the following BUG_ON during memory unplug:

kernel BUG at arch/powerpc/mm/book3s64/pgtable.c:342!
Oops: Exception in kernel mode, sig: 5 []
LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
NIP [c000000000093308] pmd_fragment_free+0x48/0xc0
LR [c00000000147bfec] remove_pagetable+0x578/0x60c
Call Trace:
0xc000008050000000 (unreliable)
remove_pagetable+0x384/0x60c
radix__remove_section_mapping+0x18/0x2c
remove_section_mapping+0x1c/0x3c
arch_remove_memory+0x11c/0x180
try_remove_memory+0x120/0x1b0
__remove_memory+0x20/0x40
dlpar_remove_lmb+0xc0/0x114
dlpar_memory+0x8b0/0xb20
handle_dlpar_errorlog+0xc0/0x190
pseries_hp_work_fn+0x2c/0x60
process_one_work+0x30c/0x810
worker_thread+0x98/0x540
kthread+0x1c4/0x1d0
ret_from_kernel_thread+0x5c/0x74

This occurs when unplug is attempted for such memory which has
been mapped using memblock pages as part of early kernel page
table setup. We wouldn't have initialized the PMD or PTE fragment
count for those PMD or PTE pages.

This can be fixed by allocating memory in PAGE_SIZE granularity
during early page table allocation. This makes sure a specific
page is not shared for another memblock allocation and we can
free them correctly on removing page-table pages.

Since we now do PAGE_SIZE allocations for both PUD table and
PMD table (Note that PTE table allocation is already of PAGE_SIZE),
we end up allocating more memory for the same amount of system RAM.
Here is a comparision of how much more we need for a 64T and 2G
system after this patch:

1. 64T system
-------------
64T RAM would need 64G for vmemmap with struct page size being 64B.

128 PUD tables for 64T memory (1G mappings)
1 PUD table and 64 PMD tables for 64G vmemmap (2M mappings)

With default PUD[PMD]_TABLE_SIZE(4K), (128+1+64)*4K=772K
With PAGE_SIZE(64K) table allocations, (128+1+64)*64K=12352K

2. 2G system
------------
2G RAM would need 2M for vmemmap with struct page size being 64B.

1 PUD table for 2G memory (1G mapping)
1 PUD table and 1 PMD table for 2M vmemmap (2M mappings)

With default PUD[PMD]_TABLE_SIZE(4K), (1+1+1)*4K=12K
With new PAGE_SIZE(64K) table allocations, (1+1+1)*64K=192K

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-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/20200709131925.922266-2-aneesh.kumar@linux.ibm.com
2020-07-20 22:57:56 +10:00
Michael Ellerman
ef9f7cfaa5 Merge branch 'fixes' into next
Merge our fixes branch, primarily to bring in the ebb selftests build
fix and the pkey fix, which is a dependency for some future work.
2020-07-18 22:43:55 +10:00
Nathan Lynch
cdf082c457 powerpc/numa: remove arch_update_cpu_topology
Since arch_update_cpu_topology() doesn't do anything on powerpc now,
remove it and associated dead code.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-15-nathanl@linux.ibm.com
2020-07-16 13:12:39 +10:00
Nathan Lynch
042ef7cc43 powerpc/numa: remove prrn_is_enabled()
All users of this prrn_is_enabled() are gone; remove it.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-14-nathanl@linux.ibm.com
2020-07-16 13:12:39 +10:00
Nathan Lynch
1835303e56 powerpc/numa: remove start/stop_topology_update()
These APIs have become no-ops, so remove them and all call sites.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-12-nathanl@linux.ibm.com
2020-07-16 13:12:38 +10:00
Nathan Lynch
b1815aeac7 powerpc/numa: remove timed_topology_update()
timed_topology_update is a no-op now, so remove it and all call sites.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-11-nathanl@linux.ibm.com
2020-07-16 13:12:37 +10:00
Nathan Lynch
893ec6461f powerpc/numa: stub out numa_update_cpu_topology()
Previous changes have removed the code which sets bits in
cpu_associativity_changes_mask and thus it is never modifed at
runtime. From this we can reason that numa_update_cpu_topology()
always returns 0 without doing anything. Remove the body of
numa_update_cpu_topology() and remove all code which becomes
unreachable as a result.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-10-nathanl@linux.ibm.com
2020-07-16 13:12:37 +10:00
Nathan Lynch
9fb8b5fd1b powerpc/numa: remove vphn_enabled and prrn_enabled internal flags
These flags are always zero now; remove them and suitably adjust the
remaining references to them.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-9-nathanl@linux.ibm.com
2020-07-16 13:12:37 +10:00
Nathan Lynch
6325cb4a4e powerpc/numa: remove unreachable topology workqueue code
Since vphn_enabled is always 0, we can remove the call to
topology_schedule_update() and remove the code which becomes
unreachable as a result.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-8-nathanl@linux.ibm.com
2020-07-16 13:12:36 +10:00
Nathan Lynch
50e0cf3742 powerpc/numa: remove unreachable topology timer code
Since vphn_enabled is always 0, we can stub out
timed_topology_update() and remove the code which becomes unreachable.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-7-nathanl@linux.ibm.com
2020-07-16 13:12:36 +10:00
Nathan Lynch
e6eacf8eb4 powerpc/numa: make vphn_enabled, prrn_enabled flags const
Previous changes have made it so these flags are never changed;
enforce this by making them const.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-6-nathanl@linux.ibm.com
2020-07-16 13:12:36 +10:00
Nathan Lynch
7d35bef96a powerpc/numa: remove unreachable topology update code
Since the topology_updates_enabled flag is now always false, remove it
and the code which has become unreachable. This is the minimum change
that prevents 'defined but unused' warnings emitted by the compiler
after stubbing out the start/stop_topology_updates() functions.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-5-nathanl@linux.ibm.com
2020-07-16 13:12:35 +10:00
Nathan Lynch
c30f931e89 powerpc/numa: remove ability to enable topology updates
Remove the /proc/powerpc/topology_updates interface and the
topology_updates=on/off command line argument. The internal
topology_updates_enabled flag remains for now, but always false.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-4-nathanl@linux.ibm.com
2020-07-16 13:12:35 +10:00
Nicholas Piggin
dd3d9aa558 powerpc/mm/book3s64/radix: Off-load TLB invalidations to host when !GTSE
When platform doesn't support GTSE, let TLB invalidation requests
for radix guests be off-loaded to the host using H_RPT_INVALIDATE
hcall.

	[hcall wrapper, error path handling and renames]

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200703053608.12884-4-bharata@linux.ibm.com
2020-07-16 13:00:21 +10:00
Bharata B Rao
029ab30b4c powerpc/mm: Enable radix GTSE only if supported.
Make GTSE an MMU feature and enable it by default for radix.
However for guest, conditionally enable it if hypervisor supports
it via OV5 vector. Let prom_init ask for radix GTSE only if the
support exists.

Having GTSE as an MMU feature will make it easy to enable radix
without GTSE. Currently radix assumes GTSE is enabled by default.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.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/20200703053608.12884-2-bharata@linux.ibm.com
2020-07-16 13:00:21 +10:00
Christophe Leroy
41ea93cf7b powerpc/kasan: Fix shadow pages allocation failure
Doing kasan pages allocation in MMU_init is too early, kernel doesn't
have access yet to the entire memory space and memblock_alloc() fails
when the kernel is a bit big.

Do it from kasan_init() instead.

Fixes: 2edb16efc8 ("powerpc/32: Add KASAN support")
Fixes: d2a91cef9b ("powerpc/kasan: Fix shadow pages allocation failure")
Cc: stable@vger.kernel.org
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=208181
Link: https://lore.kernel.org/r/63048fcea8a1c02f75429ba3152f80f7853f87fc.1593690707.git.christophe.leroy@csgroup.eu
2020-07-15 12:04:39 +10:00
Christophe Leroy
b506923ee4 Revert "powerpc/kasan: Fix shadow pages allocation failure"
This reverts commit d2a91cef9b.

This commit moved too much work in kasan_init(). The allocation
of shadow pages has to be moved for the reason explained in that
patch, but the allocation of page tables still need to be done
before switching to the final hash table.

First revert the incorrect commit, following patch redoes it
properly.

Fixes: d2a91cef9b ("powerpc/kasan: Fix shadow pages allocation failure")
Cc: stable@vger.kernel.org
Reported-by: Erhard F. <erhard_f@mailbox.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=208181
Link: https://lore.kernel.org/r/3667deb0911affbf999b99f87c31c77d5e870cd2.1593690707.git.christophe.leroy@csgroup.eu
2020-07-15 12:04:39 +10:00
Aneesh Kumar K.V
192b6a7805 powerpc/book3s64/pkeys: Fix pkey_access_permitted() for execute disable pkey
Even if the IAMR value denies execute access, the current code returns
true from pkey_access_permitted() for an execute permission check, if
the AMR read pkey bit is cleared.

This results in repeated page fault loop with a test like below:

  #define _GNU_SOURCE
  #include <errno.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <signal.h>
  #include <inttypes.h>

  #include <assert.h>
  #include <malloc.h>
  #include <unistd.h>
  #include <pthread.h>
  #include <sys/mman.h>

  #ifdef SYS_pkey_mprotect
  #undef SYS_pkey_mprotect
  #endif

  #ifdef SYS_pkey_alloc
  #undef SYS_pkey_alloc
  #endif

  #ifdef SYS_pkey_free
  #undef SYS_pkey_free
  #endif

  #undef PKEY_DISABLE_EXECUTE
  #define PKEY_DISABLE_EXECUTE	0x4

  #define SYS_pkey_mprotect	386
  #define SYS_pkey_alloc		384
  #define SYS_pkey_free		385

  #define PPC_INST_NOP		0x60000000
  #define PPC_INST_BLR		0x4e800020
  #define PROT_RWX		(PROT_READ | PROT_WRITE | PROT_EXEC)

  static int sys_pkey_mprotect(void *addr, size_t len, int prot, int pkey)
  {
  	return syscall(SYS_pkey_mprotect, addr, len, prot, pkey);
  }

  static int sys_pkey_alloc(unsigned long flags, unsigned long access_rights)
  {
  	return syscall(SYS_pkey_alloc, flags, access_rights);
  }

  static int sys_pkey_free(int pkey)
  {
  	return syscall(SYS_pkey_free, pkey);
  }

  static void do_execute(void *region)
  {
  	/* jump to region */
  	asm volatile(
  		"mtctr	%0;"
  		"bctrl"
  		: : "r"(region) : "ctr", "lr");
  }

  static void do_protect(void *region)
  {
  	size_t pgsize;
  	int i, pkey;

  	pgsize = getpagesize();

  	pkey = sys_pkey_alloc(0, PKEY_DISABLE_EXECUTE);
  	assert (pkey > 0);

  	/* perform mprotect */
  	assert(!sys_pkey_mprotect(region, pgsize, PROT_RWX, pkey));
  	do_execute(region);

  	/* free pkey */
  	assert(!sys_pkey_free(pkey));

  }

  int main(int argc, char **argv)
  {
  	size_t pgsize, numinsns;
  	unsigned int *region;
  	int i;

  	/* allocate memory region to protect */
  	pgsize = getpagesize();
  	region = memalign(pgsize, pgsize);
  	assert(region != NULL);
  	assert(!mprotect(region, pgsize, PROT_RWX));

  	/* fill page with NOPs with a BLR at the end */
  	numinsns = pgsize / sizeof(region[0]);
  	for (i = 0; i < numinsns - 1; i++)
  		region[i] = PPC_INST_NOP;
  	region[i] = PPC_INST_BLR;

  	do_protect(region);

  	return EXIT_SUCCESS;
  }

The fix is to only check the IAMR for an execute check, the AMR value
is not relevant.

Fixes: f2407ef3ba ("powerpc: helper to validate key-access permissions of a pte")
Cc: stable@vger.kernel.org # v4.16+
Reported-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Add detail to change log, tweak wording & formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200712132047.1038594-1-aneesh.kumar@linux.ibm.com
2020-07-13 16:07:17 +10:00
Aneesh Kumar K.V
19ab500edb powerpc/mm/pkeys: Make pkey access check work on execute_only_key
Jan reported that LTP mmap03 was getting stuck in a page fault loop
after commit c46241a370 ("powerpc/pkeys: Check vma before returning
key fault error to the user"), as well as a minimised reproducer:

  #include <fcntl.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <sys/mman.h>

  int main(int ac, char **av)
  {
  	int page_sz = getpagesize();
  	int fildes;
  	char *addr;

  	fildes = open("tempfile", O_WRONLY | O_CREAT, 0666);
  	write(fildes, &fildes, sizeof(fildes));
  	close(fildes);

  	fildes = open("tempfile", O_RDONLY);
  	unlink("tempfile");

  	addr = mmap(0, page_sz, PROT_EXEC, MAP_FILE | MAP_PRIVATE, fildes, 0);

  	printf("%d\n", *addr);
  	return 0;
  }

And noticed that access_pkey_error() in page fault handler now always
seem to return false:

  __do_page_fault
    access_pkey_error(is_pkey: 1, is_exec: 0, is_write: 0)
      arch_vma_access_permitted
	pkey_access_permitted
	  if (!is_pkey_enabled(pkey))
	    return true
      return false

pkey_access_permitted() should not check if the pkey is available in
UAMOR (using is_pkey_enabled()). The kernel needs to do that check
only when allocating keys. This also makes sure the execute_only_key
which is marked as non-manageable via UAMOR is handled correctly in
pkey_access_permitted(), and fixes the bug.

Fixes: c46241a370 ("powerpc/pkeys: Check vma before returning key fault error to the user")
Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Include bug report details etc. in the change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200627070147.297535-1-aneesh.kumar@linux.ibm.com
2020-06-29 16:17:02 +10:00
Arseny Solokha
7e4773f73d powerpc/fsl_booke/32: Fix build with CONFIG_RANDOMIZE_BASE
Building the current 5.8 kernel for an e500 machine with
CONFIG_RANDOMIZE_BASE=y and CONFIG_BLOCK=n yields the following
failure:

  arch/powerpc/mm/nohash/kaslr_booke.c: In function 'kaslr_early_init':
  arch/powerpc/mm/nohash/kaslr_booke.c:387:2: error: implicit
  declaration of function 'flush_icache_range'; did you mean 'flush_tlb_range'?

Indeed, including asm/cacheflush.h into kaslr_booke.c fixes the build.

Fixes: 2b0e86cc5d ("powerpc/fsl_booke/32: implement KASLR infrastructure")
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Arseny Solokha <asolokha@kb.kras.ru>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Acked-by: Scott Wood <oss@buserror.net>
[mpe: Tweak change log to mention CONFIG_BLOCK=n]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200613162801.1946619-1-asolokha@kb.kras.ru
2020-06-22 20:41:52 +10:00
Aneesh Kumar K.V
86590e524e powerpc/mm/book3s64: Skip 16G page reservation with radix
With hash translation, the hypervisor can hint the LPAR about 16GB contiguous range
via ibm,expected#pages. The kernel marks the range specified in the device tree
as reserved. Avoid doing this when using radix translation. Radix translation
only supports 1G gigantic hugepage and kernel can do the 1G gigantic hugepage
allocation via early memblock reservation. This can be done because with radix
translation pages are not required to be contiguous on the host.

Signed-off-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/20200622064019.16682-1-aneesh.kumar@linux.ibm.com
2020-06-22 20:29:51 +10:00
Christophe Leroy
7c466b0807 powerpc/ptdump: Fix build failure in hashpagetable.c
H_SUCCESS is only defined when CONFIG_PPC_PSERIES is defined.

!= H_SUCCESS means != 0. Modify the test accordingly.

Fixes: 65e701b2d2 ("powerpc/ptdump: drop non vital #ifdefs")
Cc: stable@vger.kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/795158fc1d2b3dff3bf7347881947a887ea9391a.1592227105.git.christophe.leroy@csgroup.eu
2020-06-22 10:37:58 +10:00
Joe Perches
55bd9ac468 powerpc/mm: Fix typo in IS_ENABLED()
IS_ENABLED() matches names exactly, so the missing "CONFIG_" prefix
means this code would never be built.

Also fixes a missing newline in pr_warn().

Fixes: 970d54f99c ("powerpc/book3s64/hash: Disable 16M linear mapping size if not aligned")
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/202006050717.A2F9809E@keescook
2020-06-22 10:37:58 +10:00
Andrew Morton
78c24f7bee arch/powerpc/mm/pgtable.c: another missed conversion
Fixes: e05c7b1f2b ("mm: pgtable: add shortcuts for accessing kernel PMD and PTE")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-10 14:44:46 -07:00
Michel Lespinasse
c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse
d8ed45c5dc mmap locking API: use coccinelle to convert mmap_sem rwsem call sites
This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Mike Rapoport
e05c7b1f2b mm: pgtable: add shortcuts for accessing kernel PMD and PTE
The powerpc 32-bit implementation of pgtable has nice shortcuts for
accessing kernel PMD and PTE for a given virtual address.  Make these
helpers available for all architectures.

[rppt@linux.ibm.com: microblaze: fix page table traversal in setup_rt_frame()]
  Link: http://lkml.kernel.org/r/20200518191511.GD1118872@kernel.org
[akpm@linux-foundation.org: s/pmd_ptr_k/pmd_off_k/ in various powerpc places]

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-9-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport
65fddcfca8 mm: reorder includes after introduction of linux/pgtable.h
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s <file> <header>" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include <linux/%s>" % sys.argv[2]
	moved = False
	in_hdrs = False

	with open(sys.argv[1], "r") as f:
	    lines = f.readlines()
	    for _line in lines:
		line = _line.rstrip('
')
		if line == hdr_to_move:
		    continue
		if line.startswith("#include <linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00