Commit graph

56 commits

Author SHA1 Message Date
Michael Ellerman
20045f0155 powerpc/64s/radix: Don't warn on copros in radix__tlb_flush()
Sachin reported a warning when running the inject-ra-err selftest:

  # selftests: powerpc/mce: inject-ra-err
  Disabling lock debugging due to kernel taint
  MCE: CPU19: machine check (Severe)  Real address Load/Store (foreign/control memory) [Not recovered]
  MCE: CPU19: PID: 5254 Comm: inject-ra-err NIP: [0000000010000e48]
  MCE: CPU19: Initiator CPU
  MCE: CPU19: Unknown
  ------------[ cut here ]------------
  WARNING: CPU: 19 PID: 5254 at arch/powerpc/mm/book3s64/radix_tlb.c:1221 radix__tlb_flush+0x160/0x180
  CPU: 19 PID: 5254 Comm: inject-ra-err Kdump: loaded Tainted: G   M        E      6.6.0-rc3-00055-g9ed22ae6be81 #4
  Hardware name: IBM,9080-HEX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1030.20 (NH1030_058) hv:phyp pSeries
  ...
  NIP radix__tlb_flush+0x160/0x180
  LR  radix__tlb_flush+0x104/0x180
  Call Trace:
    radix__tlb_flush+0xf4/0x180 (unreliable)
    tlb_finish_mmu+0x15c/0x1e0
    exit_mmap+0x1a0/0x510
    __mmput+0x60/0x1e0
    exit_mm+0xdc/0x170
    do_exit+0x2bc/0x5a0
    do_group_exit+0x4c/0xc0
    sys_exit_group+0x28/0x30
    system_call_exception+0x138/0x330
    system_call_vectored_common+0x15c/0x2ec

And bisected it to commit e43c0a0c3c ("powerpc/64s/radix: combine
final TLB flush and lazy tlb mm shootdown IPIs"), which added a warning
in radix__tlb_flush() if mm->context.copros is still elevated.

However it's possible for the copros count to be elevated if a process
exits without first closing file descriptors that are associated with a
copro, eg. VAS.

If the process exits with a VAS file still open, the release callback
is queued up for exit_task_work() via:
  exit_files()
    put_files_struct()
      close_files()
        filp_close()
          fput()

And called via:
  exit_task_work()
    ____fput()
      __fput()
        file->f_op->release(inode, file)
          coproc_release()
            vas_user_win_ops->close_win()
              vas_deallocate_window()
                mm_context_remove_vas_window()
                  mm_context_remove_copro()

But that is after exit_mm() has been called from do_exit() and triggered
the warning.

Fix it by dropping the warning, and always calling __flush_all_mm().

In the normal case of no copros, that will result in a call to
_tlbiel_pid(mm->context.id, RIC_FLUSH_ALL) just as the current code
does.

If the copros count is elevated then it will cause a global flush, which
should flush translations from any copros. Note that the process table
entry was cleared in arch_exit_mmap(), so copros should not be able to
fetch any new translations.

Fixes: e43c0a0c3c ("powerpc/64s/radix: combine final TLB flush and lazy tlb mm shootdown IPIs")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Closes: https://lore.kernel.org/all/A8E52547-4BF1-47CE-8AEA-BC5A9D7E3567@linux.ibm.com/
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Link: https://msgid.link/20231017121527.1574104-1-mpe@ellerman.id.au
2023-10-18 09:45:52 +11:00
Linus Torvalds
4ad0a4c234 powerpc updates for 6.6
- Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
    configured SMT state when hotplugging CPUs into the system.
 
  - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the Radix
    MMU to avoid a broadcast TLBIE flush on exit.
 
  - Drop the exclusion between ptrace/perf watchpoints, and drop the now unused
    associated arch hooks.
 
  - Add support for the "nohlt" command line option to disable CPU idle.
 
  - Add support for -fpatchable-function-entry for ftrace, with GCC >= 13.1.
 
  - Rework memory block size determination, and support 256MB size on systems
    with GPUs that have hotpluggable memory.
 
  - Various other small features and fixes.
 
 Thanks to: Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira Rajeev,
 Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam Menghani, Geoff Levand,
 Hari Bathini, Immad Mir, Jialin Zhang, Joel Stanley, Jordan Niethe, Justin
 Stitt, Kajol Jain, Kees Cook, Krzysztof Kozlowski, Laurent Dufour, Liang He,
 Linus Walleij, Mahesh Salgaonkar, Masahiro Yamada, Michal Suchanek, Nageswara
 R Sastry, Nathan Chancellor, Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick
 Desaulniers, Omar Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell
 Currey, Sourabh Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav
 Jain, Xiongfeng Wang, Yuan Tan, Zhang Rui, Zheng Zengkai.
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Merge tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Add HOTPLUG_SMT support (/sys/devices/system/cpu/smt) and honour the
   configured SMT state when hotplugging CPUs into the system

 - Combine final TLB flush and lazy TLB mm shootdown IPIs when using the
   Radix MMU to avoid a broadcast TLBIE flush on exit

 - Drop the exclusion between ptrace/perf watchpoints, and drop the now
   unused associated arch hooks

 - Add support for the "nohlt" command line option to disable CPU idle

 - Add support for -fpatchable-function-entry for ftrace, with GCC >=
   13.1

 - Rework memory block size determination, and support 256MB size on
   systems with GPUs that have hotpluggable memory

 - Various other small features and fixes

Thanks to Andrew Donnellan, Aneesh Kumar K.V, Arnd Bergmann, Athira
Rajeev, Benjamin Gray, Christophe Leroy, Frederic Barrat, Gautam
Menghani, Geoff Levand, Hari Bathini, Immad Mir, Jialin Zhang, Joel
Stanley, Jordan Niethe, Justin Stitt, Kajol Jain, Kees Cook, Krzysztof
Kozlowski, Laurent Dufour, Liang He, Linus Walleij, Mahesh Salgaonkar,
Masahiro Yamada, Michal Suchanek, Nageswara R Sastry, Nathan Chancellor,
Nathan Lynch, Naveen N Rao, Nicholas Piggin, Nick Desaulniers, Omar
Sandoval, Randy Dunlap, Reza Arbab, Rob Herring, Russell Currey, Sourabh
Jain, Thomas Gleixner, Trevor Woerner, Uwe Kleine-König, Vaibhav Jain,
Xiongfeng Wang, Yuan Tan, Zhang Rui, and Zheng Zengkai.

* tag 'powerpc-6.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (135 commits)
  macintosh/ams: linux/platform_device.h is needed
  powerpc/xmon: Reapply "Relax frame size for clang"
  powerpc/mm/book3s64: Use 256M as the upper limit with coherent device memory attached
  powerpc/mm/book3s64: Fix build error with SPARSEMEM disabled
  powerpc/iommu: Fix notifiers being shared by PCI and VIO buses
  powerpc/mpc5xxx: Add missing fwnode_handle_put()
  powerpc/config: Disable SLAB_DEBUG_ON in skiroot
  powerpc/pseries: Remove unused hcall tracing instruction
  powerpc/pseries: Fix hcall tracepoints with JUMP_LABEL=n
  powerpc: dts: add missing space before {
  powerpc/eeh: Use pci_dev_id() to simplify the code
  powerpc/64s: Move CPU -mtune options into Kconfig
  powerpc/powermac: Fix unused function warning
  powerpc/pseries: Rework lppaca_shared_proc() to avoid DEBUG_PREEMPT
  powerpc: Don't include lppaca.h in paca.h
  powerpc/pseries: Move hcall_vphn() prototype into vphn.h
  powerpc/pseries: Move VPHN constants into vphn.h
  cxl: Drop unused detach_spa()
  powerpc: Drop zalloc_maybe_bootmem()
  powerpc/powernv: Use struct opal_prd_msg in more places
  ...
2023-08-31 12:43:10 -07:00
Aneesh Kumar K.V
27af67f356 powerpc/book3s64/mm: enable transparent pud hugepage
This is enabled only with radix translation and 1G hugepage size.  This
will be used with devdax device memory with a namespace alignment of 1G.

Anon transparent hugepage is not supported even though we do have helpers
checking pud_trans_huge().  We should never find that return true.  The
only expected pte bit combination is _PAGE_PTE | _PAGE_DEVMAP.

Some of the helpers are never expected to get called on hash translation
and hence is marked to call BUG() in such a case.

Link: https://lkml.kernel.org/r/20230724190759.483013-10-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Joao Martins <joao.m.martins@oracle.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:12:55 -07:00
Alistair Popple
1af5a81099 mmu_notifiers: rename invalidate_range notifier
There are two main use cases for mmu notifiers.  One is by KVM which uses
mmu_notifier_invalidate_range_start()/end() to manage a software TLB.

The other is to manage hardware TLBs which need to use the
invalidate_range() callback because HW can establish new TLB entries at
any time.  Hence using start/end() can lead to memory corruption as these
callbacks happen too soon/late during page unmap.

mmu notifier users should therefore either use the start()/end() callbacks
or the invalidate_range() callbacks.  To make this usage clearer rename
the invalidate_range() callback to arch_invalidate_secondary_tlbs() and
update documention.

Link: https://lkml.kernel.org/r/6f77248cd25545c8020a54b4e567e8b72be4dca1.1690292440.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Suggested-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Cc: Frederic Barrat <fbarrat@linux.ibm.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nicolin Chen <nicolinc@nvidia.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zhi Wang <zhi.wang.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:12:41 -07:00
Alistair Popple
6bbd42e2df mmu_notifiers: call invalidate_range() when invalidating TLBs
The invalidate_range() is going to become an architecture specific mmu
notifier used to keep the TLB of secondary MMUs such as an IOMMU in sync
with the CPU page tables.  Currently it is called from separate code paths
to the main CPU TLB invalidations.  This can lead to a secondary TLB not
getting invalidated when required and makes it hard to reason about when
exactly the secondary TLB is invalidated.

To fix this move the notifier call to the architecture specific TLB
maintenance functions for architectures that have secondary MMUs requiring
explicit software invalidations.

This fixes a SMMU bug on ARM64.  On ARM64 PTE permission upgrades require
a TLB invalidation.  This invalidation is done by the architecture
specific ptep_set_access_flags() which calls flush_tlb_page() if required.
However this doesn't call the notifier resulting in infinite faults being
generated by devices using the SMMU if it has previously cached a
read-only PTE in it's TLB.

Moving the invalidations into the TLB invalidation functions ensures all
invalidations happen at the same time as the CPU invalidation.  The
architecture specific flush_tlb_all() routines do not call the notifier as
none of the IOMMUs require this.

Link: https://lkml.kernel.org/r/0287ae32d91393a582897d6c4db6f7456b1001f2.1690292440.git-series.apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Suggested-by: Jason Gunthorpe <jgg@ziepe.ca>
Tested-by: SeongJae Park <sj@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Andrew Donnellan <ajd@linux.ibm.com>
Cc: Chaitanya Kumar Borah <chaitanya.kumar.borah@intel.com>
Cc: Frederic Barrat <fbarrat@linux.ibm.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Nicolin Chen <nicolinc@nvidia.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Zhi Wang <zhi.wang.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-18 10:12:41 -07:00
Christophe Leroy
4a9dd8f292 powerpc/radix: Move some functions into #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
With skiboot_defconfig, Clang reports:

  CC      arch/powerpc/mm/book3s64/radix_tlb.o
arch/powerpc/mm/book3s64/radix_tlb.c:419:20: error: unused function '_tlbie_pid_lpid' [-Werror,-Wunused-function]
static inline void _tlbie_pid_lpid(unsigned long pid, unsigned long lpid,
                   ^
arch/powerpc/mm/book3s64/radix_tlb.c:663:20: error: unused function '_tlbie_va_range_lpid' [-Werror,-Wunused-function]
static inline void _tlbie_va_range_lpid(unsigned long start, unsigned long end,
                   ^

This is because those functions are only called from functions
enclosed in a #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE

Move below functions inside that #ifdef
* __tlbie_pid_lpid(unsigned long pid,
* __tlbie_va_lpid(unsigned long va, unsigned long pid,
* fixup_tlbie_pid_lpid(unsigned long pid, unsigned long lpid)
* _tlbie_pid_lpid(unsigned long pid, unsigned long lpid,
* fixup_tlbie_va_range_lpid(unsigned long va,
* __tlbie_va_range_lpid(unsigned long start, unsigned long end,
* _tlbie_va_range_lpid(unsigned long start, unsigned long end,

Fixes: f0c6fbbb90 ("KVM: PPC: Book3S HV: Add support for H_RPT_INVALIDATE")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202307260802.Mjr99P5O-lkp@intel.com/
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/3d72efd39f986ee939d068af69fdce28bd600766.1691568093.git.christophe.leroy@csgroup.eu
2023-08-14 21:54:04 +10:00
Nicholas Piggin
e43c0a0c3c powerpc/64s/radix: combine final TLB flush and lazy tlb mm shootdown IPIs
This performs lazy tlb mm shootdown when doing the exit TLB flush when
all mm users go away and user mappings are removed, which avoids having
to do the lazy tlb mm shootdown IPIs on the final mmput when all kernel
references disappear.

powerpc/64s uses a broadcast TLBIE for the exit TLB flush if remote CPUs
need to be invalidated (unless TLBIE is disabled), so this doesn't
necessarily save IPIs but it does avoid a broadcast TLBIE which is quite
expensive.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Squash in preempt_disable/enable() fix from Nick]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230524060821.148015-5-npiggin@gmail.com
2023-08-02 22:22:19 +10:00
Nicholas Piggin
f74b2a6c01 powerpc/64s: Use dec_mm_active_cpus helper
Avoid open-coded atomic_dec on mm->context.active_cpus and use the
function made for it. Add CONFIG_DEBUG_VM underflow checking on the
counter.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230524060821.148015-3-npiggin@gmail.com
2023-08-02 22:22:18 +10:00
Nicholas Piggin
dfaed3e1fa powerpc/64s/radix: Fix exit lazy tlb mm switch with irqs enabled
Switching mm and tinkering with current->active_mm should be done with
irqs disabled. There is a path where exit_lazy_flush_tlb can be called
with irqs enabled:

    exit_lazy_flush_tlb
    flush_type_needed
    __flush_all_mm
    tlb_finish_mmu
    exit_mmap

Which results in the switching being done with irqs enabled, which is
incorrect.

Fixes: a665eec0a2 ("powerpc/64s/radix: Fix mm_cpumask trimming race vs kthread_use_mm")
Cc: stable@vger.kernel.org # v5.10+
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Link: https://lore.kernel.org/linuxppc-dev/A9A5D83D-BA70-47A4-BCB4-30C1AE19BC22@linux.ibm.com/
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230607005601.583293-1-npiggin@gmail.com
2023-06-09 16:35:52 +10:00
Nicholas Piggin
aa464ba9a1 lazy tlb: introduce lazy tlb mm refcount helper functions
Add explicit _lazy_tlb annotated functions for lazy tlb mm refcounting. 
This makes the lazy tlb mm references more obvious, and allows the
refcounting scheme to be modified in later changes.  There is no
functional change with this patch.

Link: https://lkml.kernel.org/r/20230203071837.1136453-3-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nadav Amit <nadav.amit@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-28 16:20:08 -07:00
Anders Roxell
d78c8e3289 powerpc/mm: Rearrange if-else block to avoid clang warning
Clang warns:

  arch/powerpc/mm/book3s64/radix_tlb.c:1191:23: error: variable 'hstart' is uninitialized when used here
    __tlbiel_va_range(hstart, hend, pid,
                      ^~~~~~
  arch/powerpc/mm/book3s64/radix_tlb.c:1191:31: error: variable 'hend' is uninitialized when used here
    __tlbiel_va_range(hstart, hend, pid,
                              ^~~~

Rework the 'if (IS_ENABLE(CONFIG_TRANSPARENT_HUGEPAGE))' so hstart/hend
is always initialized to silence the warnings. That will also simplify
the 'else' path. Clang is getting confused with these warnings, but the
warnings is a false-positive.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220810114318.3220630-1-anders.roxell@linaro.org
2023-02-16 23:53:16 +11:00
Nicholas Piggin
dcfecb989a powerpc/64s/radix: Remove TLB_FLUSH_ALL test from range flushes
This looks like it came across from x86, but x86 uses TLB_FLUSH_ALL as
a parameter to internal functions. Powerpc never sets it anywhere.

Remove the associated logic and leave a warning for now.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230203111718.1149852-4-npiggin@gmail.com
2023-02-08 21:42:12 +11:00
Nicholas Piggin
d01dc25e47 powerpc/64s/radix: mm->context.id should always be valid
The MMU_NO_CONTEXT checks are an unnecessary complication. Make
these warn to prepare to remove them in future.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230203111718.1149852-3-npiggin@gmail.com
2023-02-08 21:42:12 +11:00
Nicholas Piggin
45abf5d94b powerpc/64s/radix: Remove need_flush_all test from radix__tlb_flush
need_flush_all is only set by arch code to instruct generic tlb_flush
to flush all. It is never set by powerpc, so it can be removed.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230203111718.1149852-2-npiggin@gmail.com
2023-02-08 21:42:12 +11:00
Nicholas Piggin
abf0878ce9 powerpc/64s: POWER10 nest MMU does not require flush escalation workaround
Per (non-public) Nest MMU Workbook, POWER10 and POWER9P NMMU does not
cache PTEs in PWC, so does not require PWC flush to invalidate these
translations.

Skip the workaround on POWER10 and later.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220525022358.780745-2-npiggin@gmail.com
2022-07-27 21:36:04 +10:00
Julia Lawall
1fd02f6605 powerpc: fix typos in comments
Various spelling mistakes in comments.
Detected with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220430185654.5855-1-Julia.Lawall@inria.fr
2022-05-05 22:12:44 +10:00
Aneesh Kumar K.V
dbf77fed8b powerpc: rename powerpc_debugfs_root to arch_debugfs_dir
No functional change in this patch. arch_debugfs_dir is the generic kernel
name declared in linux/debugfs.h for arch-specific debugfs directory.
Architectures like x86/s390 already use the name. Rename powerpc
specific powerpc_debugfs_root to arch_debugfs_dir.

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/20210812132831.233794-2-aneesh.kumar@linux.ibm.com
2021-08-13 22:04:26 +10:00
Aneesh Kumar K.V
3e188b1ae8 powerpc/book3s64/radix: make tlb_single_page_flush_ceiling a debugfs entry
Similar to x86/s390 add a debugfs file to tune tlb_single_page_flush_ceiling.
Also add a debugfs entry for tlb_local_single_page_flush_ceiling.

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/20210812132831.233794-1-aneesh.kumar@linux.ibm.com
2021-08-13 22:04:26 +10:00
Aneesh Kumar K.V
cec6515abb powerpc/book3s64/mm: update flush_tlb_range to flush page walk cache
flush_tlb_range is special in that we don't specify the page size used for
the translation.  Hence when flushing TLB we flush the translation cache
for all possible page sizes.  The kernel also uses the same interface when
moving page tables around.  Such a move requires us to flush the page walk
cache.

Instead of adding another interface to force page walk cache flush, update
flush_tlb_range to flush page walk cache if the range flushed is more than
the PMD range.  A page table move will always involve an invalidate range
more than PMD_SIZE.

Running microbenchmark with mprotect and parallel memory access didn't
show any observable performance impact.

Link: https://lkml.kernel.org/r/20210616045735.374532-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Kalesh Singh <kaleshsingh@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:23 -07:00
Michael Ellerman
a736143afd Merge branch 'topic/ppc-kvm' into next
Pull in some more ppc KVM patches we are keeping in our topic branch.

In particular this brings in the series to add H_RPT_INVALIDATE.
2021-06-23 00:19:08 +10:00
Bharata B Rao
53324b51c5 KVM: PPC: Book3S HV: Nested support in H_RPT_INVALIDATE
Enable support for process-scoped invalidations from nested
guests and partition-scoped invalidations for nested guests.

Process-scoped invalidations for any level of nested guests
are handled by implementing H_RPT_INVALIDATE handler in the
nested guest exit path in L0.

Partition-scoped invalidation requests are forwarded to the
right nested guest, handled there and passed down to L0
for eventual handling.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
[aneesh: Nested guest partition-scoped invalidation changes]
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Squash in fixup patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210621085003.904767-5-bharata@linux.ibm.com
2021-06-22 23:35:37 +10:00
Bharata B Rao
f0c6fbbb90 KVM: PPC: Book3S HV: Add support for H_RPT_INVALIDATE
H_RPT_INVALIDATE does two types of TLB invalidations:

1. Process-scoped invalidations for guests when LPCR[GTSE]=0.
   This is currently not used in KVM as GTSE is not usually
   disabled in KVM.
2. Partition-scoped invalidations that an L1 hypervisor does on
   behalf of an L2 guest. This is currently handled
   by H_TLB_INVALIDATE hcall and this new replaces the old that.

This commit enables process-scoped invalidations for L1 guests.
Support for process-scoped and partition-scoped invalidations
from/for nested guests will be added separately.

Process scoped tlbie invalidations from L1 and nested guests
need RS register for TLBIE instruction to contain both PID and
LPID.  This patch introduces primitives that execute tlbie
instruction with both PID and LPID set in prepartion for
H_RPT_INVALIDATE hcall.

A description of H_RPT_INVALIDATE follows:

int64   /* H_Success: Return code on successful completion */
        /* H_Busy - repeat the call with the same */
        /* H_Parameter, H_P2, H_P3, H_P4, H_P5 : Invalid
	   parameters */
hcall(const uint64 H_RPT_INVALIDATE, /* Invalidate RPT
					translation
					lookaside information */
      uint64 id,        /* PID/LPID to invalidate */
      uint64 target,    /* Invalidation target */
      uint64 type,      /* Type of lookaside information */
      uint64 pg_sizes,  /* Page sizes */
      uint64 start,     /* Start of Effective Address (EA)
			   range (inclusive) */
      uint64 end)       /* End of EA range (exclusive) */

Invalidation targets (target)
-----------------------------
Core MMU        0x01 /* All virtual processors in the
			partition */
Core local MMU  0x02 /* Current virtual processor */
Nest MMU        0x04 /* All nest/accelerator agents
			in use by the partition */

A combination of the above can be specified,
except core and core local.

Type of translation to invalidate (type)
---------------------------------------
NESTED       0x0001  /* invalidate nested guest partition-scope */
TLB          0x0002  /* Invalidate TLB */
PWC          0x0004  /* Invalidate Page Walk Cache */
PRT          0x0008  /* Invalidate caching of Process Table
			Entries if NESTED is clear */
PAT          0x0008  /* Invalidate caching of Partition Table
			Entries if NESTED is set */

A combination of the above can be specified.

Page size mask (pages)
----------------------
4K              0x01
64K             0x02
2M              0x04
1G              0x08
All sizes       (-1UL)

A combination of the above can be specified.
All page sizes can be selected with -1.

Semantics: Invalidate radix tree lookaside information
           matching the parameters given.
* Return H_P2, H_P3 or H_P4 if target, type, or pageSizes parameters
  are different from the defined values.
* Return H_PARAMETER if NESTED is set and pid is not a valid nested
  LPID allocated to this partition
* Return H_P5 if (start, end) doesn't form a valid range. Start and
  end should be a valid Quadrant address and  end > start.
* Return H_NotSupported if the partition is not in running in radix
  translation mode.
* May invalidate more translation information than requested.
* If start = 0 and end = -1, set the range to cover all valid
  addresses. Else start and end should be aligned to 4kB (lower 11
  bits clear).
* If NESTED is clear, then invalidate process scoped lookaside
  information. Else pid specifies a nested LPID, and the invalidation
  is performed   on nested guest partition table and nested guest
  partition scope real addresses.
* If pid = 0 and NESTED is clear, then valid addresses are quadrant 3
  and quadrant 0 spaces, Else valid addresses are quadrant 0.
* Pages which are fully covered by the range are to be invalidated.
  Those which are partially covered are considered outside
  invalidation range, which allows a caller to optimally invalidate
  ranges that may   contain mixed page sizes.
* Return H_SUCCESS on success.

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/20210621085003.904767-4-bharata@linux.ibm.com
2021-06-21 22:54:27 +10:00
Michael Ellerman
3c53642324 Merge branch 'topic/ppc-kvm' into next
Merge some powerpc KVM patches from our topic branch.

In particular this brings in Nick's big series rewriting parts of the
guest entry/exit path in C.

Conflicts:
	arch/powerpc/kernel/security.c
	arch/powerpc/kvm/book3s_hv_rmhandlers.S
2021-06-17 16:51:38 +10:00
Aneesh Kumar K.V
07d8ad6fd8 powerpc/mm/book3s64: Fix possible build error
Update _tlbiel_pid() such that we can avoid build errors like below when
using this function in other places.

arch/powerpc/mm/book3s64/radix_tlb.c: In function ‘__radix__flush_tlb_range_psize’:
arch/powerpc/mm/book3s64/radix_tlb.c:114:2: warning: ‘asm’ operand 3 probably does not match constraints
  114 |  asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
      |  ^~~
arch/powerpc/mm/book3s64/radix_tlb.c:114:2: error: impossible constraint in ‘asm’
make[4]: *** [scripts/Makefile.build:271: arch/powerpc/mm/book3s64/radix_tlb.o] Error 1
m

With this fix, we can also drop the __always_inline in __radix_flush_tlb_range_psize
which was added by commit e12d6d7d46 ("powerpc/mm/radix: mark __radix__flush_tlb_range_psize() as __always_inline")

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210610083639.387365-1-aneesh.kumar@linux.ibm.com
2021-06-17 16:25:50 +10:00
Nicholas Piggin
2e1ae9cd56 KVM: PPC: Book3S HV: Implement radix prefetch workaround by disabling MMU
Rather than partition the guest PID space + flush a rogue guest PID to
work around this problem, instead fix it by always disabling the MMU when
switching in or out of guest MMU context in HV mode.

This may be a bit less efficient, but it is a lot less complicated and
allows the P9 path to trivally implement the workaround too. Newer CPUs
are not subject to this issue.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210528090752.3542186-22-npiggin@gmail.com
2021-06-10 22:12:14 +10:00
Michael Ellerman
2bb421a3d9 powerpc/mm/64s: Fix no previous prototype warning
As reported by lkp:

  arch/powerpc/mm/book3s64/radix_tlb.c:646:6: warning: no previous
  prototype for function 'exit_lazy_flush_tlb'

Fix it by moving the prototype into the existing header.

Fixes: 032b7f0893 ("powerpc/64s/radix: serialize_against_pte_lookup IPIs trim mm_cpumask")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210210130804.3190952-2-mpe@ellerman.id.au
2021-02-11 23:28:51 +11:00
Nicholas Piggin
032b7f0893 powerpc/64s/radix: serialize_against_pte_lookup IPIs trim mm_cpumask
serialize_against_pte_lookup() performs IPIs to all CPUs in mm_cpumask.
Take this opportunity to try trim the CPU out of mm_cpumask. This can
reduce the cost of future serialize_against_pte_lookup() and/or the
cost of future TLB flushes.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201217134731.488135-7-npiggin@gmail.com
2021-02-09 01:09:45 +11:00
Nicholas Piggin
9393544842 powerpc/64s/radix: occasionally attempt to trim mm_cpumask
A single-threaded process that is flushing its own address space is
so far the only case where the mm_cpumask is attempted to be trimmed.
This patch expands that to flush in other situations, multi-threaded
processes and external sources. For now it's a relatively simple
occasional trim attempt. The main aim is to add the mechanism,
tweaking and tuning can come with more data.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201217134731.488135-6-npiggin@gmail.com
2021-02-09 01:09:45 +11:00
Nicholas Piggin
780de40601 powerpc/64s/radix: Allow mm_cpumask trimming from external sources
mm_cpumask trimming is currently restricted to be issued by the current
thread of a single-threaded mm. This patch relaxes that and allows the
mask to be trimmed from any context.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201217134731.488135-5-npiggin@gmail.com
2021-02-09 01:09:44 +11:00
Nicholas Piggin
54bb503345 powerpc/64s/radix: Check for no TLB flush required
If there are no CPUs in mm_cpumask, no TLB flush is required at all.
This patch adds a check for this case.

Currently it's not tested for, in fact mm_is_thread_local() returns
false if the current CPU is not in mm_cpumask, so it's treated as a
global flush.

This can come up in some cases like exec failure before the new mm has
ever been switched to. This patch reduces TLBIE instructions required
to build a kernel from about 120,000 to 45,000. Another situation it
could help is page reclaim, KSM, THP, etc., (i.e., asynch operations
external to the process) where the process is sleeping and has all TLBs
flushed out of all CPUs.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201217134731.488135-4-npiggin@gmail.com
2021-02-09 01:09:44 +11:00
Nicholas Piggin
26418b36a1 powerpc/64s/radix: refactor TLB flush type selection
The logic to decide what kind of TLB flush is required (local, global,
or IPI) is spread multiple times over the several kinds of TLB flushes.

Move it all into a single function which may issue IPIs if necessary,
and also returns a flush type that is to be used.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201217134731.488135-3-npiggin@gmail.com
2021-02-09 01:09:44 +11:00
Nicholas Piggin
a2496049f1 powerpc/64s/radix: add warning and comments in mm_cpumask trim
Add a comment explaining part of the logic for mm_cpumask trimming, and
add a (hopefully graceful) check and warning in case something gets it
wrong.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201217134731.488135-2-npiggin@gmail.com
2021-02-09 01:09:44 +11:00
Aneesh Kumar K.V
e80639405c powerpc/mm: Update tlbiel loop on POWER10
With POWER10, single tlbiel instruction invalidates all the congruence
class of the TLB and hence we need to issue only one tlbiel with SET=0.

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/20201007053305.232879-1-aneesh.kumar@linux.ibm.com
2020-11-19 14:50:15 +11:00
Nicholas Piggin
05504b4256 powerpc/64s: Add cp_abort after tlbiel to invalidate copy-buffer address
The copy buffer is implemented as a real address in the nest which is
translated from EA by copy, and used for memory access by paste. This
requires that it be invalidated by TLB invalidation.

TLBIE does invalidate the copy buffer, but TLBIEL does not. Add
cp_abort to the tlbiel sequence.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Fixup whitespace and comment formatting]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200916030234.4110379-2-npiggin@gmail.com
2020-10-06 23:22:23 +11:00
Nicholas Piggin
a665eec0a2 powerpc/64s/radix: Fix mm_cpumask trimming race vs kthread_use_mm
Commit 0cef77c779 ("powerpc/64s/radix: flush remote CPUs out of
single-threaded mm_cpumask") added a mechanism to trim the mm_cpumask of
a process under certain conditions. One of the assumptions is that
mm_users would not be incremented via a reference outside the process
context with mmget_not_zero() then go on to kthread_use_mm() via that
reference.

That invariant was broken by io_uring code (see previous sparc64 fix),
but I'll point Fixes: to the original powerpc commit because we are
changing that assumption going forward, so this will make backports
match up.

Fix this by no longer relying on that assumption, but by having each CPU
check the mm is not being used, and clearing their own bit from the mask
only if it hasn't been switched-to by the time the IPI is processed.

This relies on commit 38cf307c1f ("mm: fix kthread_use_mm() vs TLB
invalidate") and ARCH_WANT_IRQS_OFF_ACTIVATE_MM to disable irqs over mm
switch sequences.

Fixes: 0cef77c779 ("powerpc/64s/radix: flush remote CPUs out of single-threaded mm_cpumask")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Depends-on: 38cf307c1f ("mm: fix kthread_use_mm() vs TLB invalidate")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200914045219.3736466-5-npiggin@gmail.com
2020-09-16 12:24:37 +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
Aneesh Kumar K.V
8f53f9c0f6 powerpc/book3s64/radix/tlb: Determine hugepage flush correctly
With a 64K page size flush with start and end:

  (start, end) = (721f680d0000, 721f680e0000)

results in:

  (hstart, hend) = (721f68200000, 721f68000000)

ie. hstart is above hend, which indicates no huge page flush is
needed.

However the current logic incorrectly sets hflush = true in this case,
because hstart != hend.

That causes us to call __tlbie_va_range() passing hstart/hend, to do a
huge page flush even though we don't need to. __tlbie_va_range() will
skip the actual tlbie operation for start > end. But it will still end
up calling fixup_tlbie_va_range() and doing the TLB fixups in there,
which is harmless but unnecessary work.

Reported-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Drop else case, hflush is already false, flesh out change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200513030616.152288-1-aneesh.kumar@linux.ibm.com
2020-05-20 23:39:55 +10:00
Nicholas Piggin
993cfecc59 powerpc/64s/radix: Fix CONFIG_SMP=n build
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200302010410.2957362-1-npiggin@gmail.com
2020-03-18 00:05:54 +11:00
Jordan Niethe
736bcdd3a9 powerpc/mm: Remove kvm radix prefetch workaround for Power9 DD2.2
Commit a25bd72bad ("powerpc/mm/radix: Workaround prefetch issue with
KVM") introduced a number of workarounds as coming out of a guest with
the mmu enabled would make the cpu would start running in hypervisor
state with the PID value from the guest. The cpu will then start
prefetching for the hypervisor with that PID value.

In Power9 DD2.2 the cpu behaviour was modified to fix this. When
accessing Quadrant 0 in hypervisor mode with LPID != 0 prefetching will
not be performed. This means that we can get rid of the workarounds for
Power9 DD2.2 and later revisions. Add a new cpu feature
CPU_FTR_P9_RADIX_PREFETCH_BUG to indicate if the workarounds are needed.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191206031722.25781-1-jniethe5@gmail.com
2020-01-26 00:11:37 +11:00
Aneesh Kumar K.V
864edb758c powerpc/mm/book3s64/radix: Flush the full mm even when need_flush_all is set
With the previous patch, we should now not be using need_flush_all for
powerpc. But then make sure we force a PID tlbie flush with RIC=2 if
we ever find need_flush_all set. Also don't reset it after a mmu
gather flush.

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/20191024075801.22434-3-aneesh.kumar@linux.ibm.com
2019-11-05 22:24:18 +11:00
Aneesh Kumar K.V
52162ec784 powerpc/mm/book3s64/radix: Use freed_tables instead of need_flush_all
With commit 22a61c3c4f ("asm-generic/tlb: Track freeing of
page-table directories in struct mmu_gather") we now track whether we
freed page table in mmu_gather. Use that to decide whether to flush
Page Walk Cache.

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/20191024075801.22434-2-aneesh.kumar@linux.ibm.com
2019-11-05 22:23:55 +11:00
Aneesh Kumar K.V
a42d6ba8c5 powerpc/mm/book3s64/radix: Remove unused code.
mm_tlb_flush_nested change was added in the mmu gather tlb flush to
handle the case of parallel pte invalidate happening with mmap_sem
held in read mode. This fix was done by commit
02390f66bd ("powerpc/64s/radix: Fix MADV_[FREE|DONTNEED] TLB flush
miss problem with THP") and the problem is explained in detail in
commit 99baac21e4 ("mm: fix MADV_[FREE|DONTNEED] TLB flush miss
problem")

This was later updated by commit 7a30df49f6 ("mm: mmu_gather: remove
__tlb_reset_range() for force flush") to do a full mm flush rather
than a range flush. By commit dd2283f260 ("mm: mmap: zap pages with
read mmap_sem in munmap") we are also now allowing a page table free
in mmap_sem read mode which means we should do a PWC flush too. Our
current full mm flush imply a PWC flush.

With all the above change the mm_tlb_flush_nested(mm) branch in
radix__tlb_flush will never be taken because for the nested case we
would have taken the if (tlb->fullmm) branch. This patch removes the
unused code. Also, remove the gflush change in
__radix__flush_tlb_range that was added to handle the range tlb flush
code. We only check for THP there because hugetlb is flushed via a
different code path where page size is explicitly specified.

This is a partial revert of commit 02390f66bd ("powerpc/64s/radix:
Fix MADV_[FREE|DONTNEED] TLB flush miss problem with THP")

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/20191024075801.22434-1-aneesh.kumar@linux.ibm.com
2019-11-05 22:23:17 +11:00
Aneesh Kumar K.V
047e6575ae powerpc/mm: Fixup tlbie vs mtpidr/mtlpidr ordering issue on POWER9
On POWER9, under some circumstances, a broadcast TLB invalidation will
fail to invalidate the ERAT cache on some threads when there are
parallel mtpidr/mtlpidr happening on other threads of the same core.
This can cause stores to continue to go to a page after it's unmapped.

The workaround is to force an ERAT flush using PID=0 or LPID=0 tlbie
flush. This additional TLB flush will cause the ERAT cache
invalidation. Since we are using PID=0 or LPID=0, we don't get
filtered out by the TLB snoop filtering logic.

We need to still follow this up with another tlbie to take care of
store vs tlbie ordering issue explained in commit:
a5d4b5891c ("powerpc/mm: Fixup tlbie vs store ordering issue on
POWER9"). The presence of ERAT cache implies we can still get new
stores and they may miss store queue marking flush.

Cc: stable@vger.kernel.org
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/20190924035254.24612-3-aneesh.kumar@linux.ibm.com
2019-09-24 20:58:55 +10:00
Aneesh Kumar K.V
09ce98cacd powerpc/book3s64/radix: Rename CPU_FTR_P9_TLBIE_BUG feature flag
Rename the #define to indicate this is related to store vs tlbie
ordering issue. In the next patch, we will be adding another feature
flag that is used to handles ERAT flush vs tlbie ordering issue.

Fixes: a5d4b5891c ("powerpc/mm: Fixup tlbie vs store ordering issue on POWER9")
Cc: stable@vger.kernel.org # v4.16+
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/20190924035254.24612-2-aneesh.kumar@linux.ibm.com
2019-09-24 20:58:47 +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
7e71c428a6 powerpc/64s/pseries: radix flush translations before MMU is enabled at boot
Radix guests are responsible for managing their own translation caches,
so make them match bare metal radix and hash, and make each CPU flush
all its translations right before enabling its MMU.

Radix guests may not flush partition scope translations, so in
tlbiel_all, make these flushes conditional on CPU_FTR_HVMODE. Process
scope translations are the only type visible to the guest.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190902152931.17840-5-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
Linus Torvalds
192f0f8e9d powerpc updates for 5.3
Notable changes:
 
  - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver, as well
    as some other functions only used by drivers that haven't (yet?) made it
    upstream.
 
  - A fix for a bug in our handling of hardware watchpoints (eg. perf record -e
    mem: ...) which could lead to register corruption and kernel crashes.
 
  - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for vmalloc
    when using the Radix MMU.
 
  - A large but incremental rewrite of our exception handling code to use gas
    macros rather than multiple levels of nested CPP macros.
 
 And the usual small fixes, cleanups and improvements.
 
 Thanks to:
   Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab, Aneesh Kumar K.V, Anju
   T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Cédric Le Goater,
   Christian Lamparter, Christophe Leroy, Christophe Lombard, Christoph Hellwig,
   Daniel Axtens, Denis Efremov, Enrico Weigelt, Frederic Barrat, Gautham R.
   Shenoy, Geert Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg
   Kurz, Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
   Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N. Rao,
   Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi Bangoria,
   Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher Boessenkool, Shaokun
   Zhang, Shawn Anastasio, Stewart Smith, Suraj Jitindar Singh, Thiago Jung
   Bauermann, YueHaibing.
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Merge tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Removal of the NPU DMA code, used by the out-of-tree Nvidia driver,
     as well as some other functions only used by drivers that haven't
     (yet?) made it upstream.

   - A fix for a bug in our handling of hardware watchpoints (eg. perf
     record -e mem: ...) which could lead to register corruption and
     kernel crashes.

   - Enable HAVE_ARCH_HUGE_VMAP, which allows us to use large pages for
     vmalloc when using the Radix MMU.

   - A large but incremental rewrite of our exception handling code to
     use gas macros rather than multiple levels of nested CPP macros.

  And the usual small fixes, cleanups and improvements.

  Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Andreas Schwab,
  Aneesh Kumar K.V, Anju T Sudhakar, Anton Blanchard, Arnd Bergmann,
  Athira Rajeev, Cédric Le Goater, Christian Lamparter, Christophe
  Leroy, Christophe Lombard, Christoph Hellwig, Daniel Axtens, Denis
  Efremov, Enrico Weigelt, Frederic Barrat, Gautham R. Shenoy, Geert
  Uytterhoeven, Geliang Tang, Gen Zhang, Greg Kroah-Hartman, Greg Kurz,
  Gustavo Romero, Krzysztof Kozlowski, Madhavan Srinivasan, Masahiro
  Yamada, Mathieu Malaterre, Michael Neuling, Nathan Lynch, Naveen N.
  Rao, Nicholas Piggin, Nishad Kamdar, Oliver O'Halloran, Qian Cai, Ravi
  Bangoria, Sachin Sant, Sam Bobroff, Satheesh Rajendran, Segher
  Boessenkool, Shaokun Zhang, Shawn Anastasio, Stewart Smith, Suraj
  Jitindar Singh, Thiago Jung Bauermann, YueHaibing"

* tag 'powerpc-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (163 commits)
  powerpc/powernv/idle: Fix restore of SPRN_LDBAR for POWER9 stop state.
  powerpc/eeh: Handle hugepages in ioremap space
  ocxl: Update for AFU descriptor template version 1.1
  powerpc/boot: pass CONFIG options in a simpler and more robust way
  powerpc/boot: add {get, put}_unaligned_be32 to xz_config.h
  powerpc/irq: Don't WARN continuously in arch_local_irq_restore()
  powerpc/module64: Use symbolic instructions names.
  powerpc/module32: Use symbolic instructions names.
  powerpc: Move PPC_HA() PPC_HI() and PPC_LO() to ppc-opcode.h
  powerpc/module64: Fix comment in R_PPC64_ENTRY handling
  powerpc/boot: Add lzo support for uImage
  powerpc/boot: Add lzma support for uImage
  powerpc/boot: don't force gzipped uImage
  powerpc/8xx: Add microcode patch to move SMC parameter RAM.
  powerpc/8xx: Use IO accessors in microcode programming.
  powerpc/8xx: replace #ifdefs by IS_ENABLED() in microcode.c
  powerpc/8xx: refactor programming of microcode CPM params.
  powerpc/8xx: refactor printing of microcode patch name.
  powerpc/8xx: Refactor microcode write
  powerpc/8xx: refactor writing of CPM microcode arrays
  ...
2019-07-13 16:08:36 -07:00
Alastair D'Silva
60e8523e2e ocxl: Allow contexts to be attached with a NULL mm
If an OpenCAPI context is to be used directly by a kernel driver, there
may not be a suitable mm to use.

The patch makes the mm parameter to ocxl_context_attach optional.

Signed-off-by: Alastair D'Silva <alastair@d-silva.org>
Acked-by: Andrew Donnellan <ajd@linux.ibm.com>
Acked-by: Frederic Barrat <fbarrat@linux.ibm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Link: https://lore.kernel.org/r/20190620041203.12274-1-alastair@au1.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-07-03 21:29:47 +02:00
Masahiro Yamada
6d3ca7e736 powerpc/mm: mark more tlb functions as __always_inline
With CONFIG_OPTIMIZE_INLINING enabled, Laura Abbott reported error
with gcc 9.1.1:

  arch/powerpc/mm/book3s64/radix_tlb.c: In function '_tlbiel_pid':
  arch/powerpc/mm/book3s64/radix_tlb.c:104:2: warning: asm operand 3 probably doesn't match constraints
    104 |  asm volatile(PPC_TLBIEL(%0, %4, %3, %2, %1)
        |  ^~~
  arch/powerpc/mm/book3s64/radix_tlb.c:104:2: error: impossible constraint in 'asm'

Fixing _tlbiel_pid() is enough to address the warning above, but I
inlined more functions to fix all potential issues.

To meet the "i" (immediate) constraint for the asm operands, functions
propagating "ric" must be always inlined.

Fixes: 9012d01166 ("compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-03 20:49:50 +10:00