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Author SHA1 Message Date
Robin Murphy 175967318c mm: introduce ARCH_HAS_PTE_DEVMAP
ARCH_HAS_ZONE_DEVICE is somewhat meaningless in itself, and combined
with the long-out-of-date comment can lead to the impression than an
architecture may just enable it (since __add_pages() now "comprehends
device memory" for itself) and expect things to work.

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

Link: http://lkml.kernel.org/r/87554aa78478a02a63f2c4cf60a847279ae3eb3b.1558547956.git.robin.murphy@arm.com
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-07-16 19:23:25 -07:00
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
Aneesh Kumar K.V d6eacedd1f powerpc/book3s: Use config independent helpers for page table walk
Even when we have HugeTLB and THP disabled, kernel linear map can still be
mapped with hugepages. This is only an issue with radix translation because hash
MMU doesn't map kernel linear range in linux page table and other kernel
map areas are not mapped using hugepage.

Add config independent helpers and put WARN_ON() when we don't expect things
to be mapped via hugepages.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-05 00:43:50 +10:00
Aneesh Kumar K.V b8c8a524cc powerpc/mm: Remove unused variable declaration
Since commit 0034d395f8 ("powerpc/mm/hash64: Map all the kernel
regions in the same 0xc range") __kernel_virt_size is not used
anymore.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-05 00:20:42 +10:00
Christoph Hellwig 7eb3cf7619 powerpc/powernv: remove unused NPU DMA code
None of these routines were ever used anywhere in the kernel tree
since they were added to the kernel.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-07-01 16:26:55 +10:00
Michael Ellerman 8b8dc69514 Merge branch 'fixes' into next
Merge our fixes branch into next, this brings in a number of commits
that fix bugs we don't want to hit in next, in particular the fix for
CVE-2019-12817.
2019-07-01 14:04:39 +10:00
Nicholas Piggin d909f9109c powerpc/64s/radix: Enable HAVE_ARCH_HUGE_VMAP
This sets the HAVE_ARCH_HUGE_VMAP option, and defines the required
page table functions.

This enables huge (2MB and 1GB) ioremap mappings. I don't have a
benchmark for this change, but huge vmap will be used by a later core
kernel change to enable huge vmalloc memory mappings. This improves
cached `git diff` performance by about 5% on a 2-node POWER9 with 32MB
size dentry cache hash.

  Profiling git diff dTLB misses with a vanilla kernel:

  81.75%  git      [kernel.vmlinux]    [k] __d_lookup_rcu
   7.21%  git      [kernel.vmlinux]    [k] strncpy_from_user
   1.77%  git      [kernel.vmlinux]    [k] find_get_entry
   1.59%  git      [kernel.vmlinux]    [k] kmem_cache_free

            40,168      dTLB-miss
       0.100342754 seconds time elapsed

  With powerpc huge vmalloc:

             2,987      dTLB-miss
       0.095933138 seconds time elapsed

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-06-19 20:05:09 +10:00
Nicholas Piggin d38153f9cc powerpc/64s/radix: ioremap use ioremap_page_range
Radix can use ioremap_page_range for ioremap, after slab is available.
This makes it possible to enable huge ioremap mapping support.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-06-19 20:05:09 +10:00
Linus Torvalds fa1827d773 powerpc fixes for 5.2 #4
One fix for a regression introduced by our 32-bit KASAN support, which broke
 booting on machines with "bootx" early debugging enabled.
 
 A fix for a bug which broke kexec on 32-bit, introduced by changes to the 32-bit
 STRICT_KERNEL_RWX support in v5.1.
 
 Finally two fixes going to stable for our THP split/collapse handling,
 discovered by Nick. The first fixes random crashes and/or corruption in guests
 under sufficient load.
 
 Thanks to:
   Nicholas Piggin, Christophe Leroy, Aaro Koskinen, Mathieu Malaterre.
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Merge tag 'powerpc-5.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "One fix for a regression introduced by our 32-bit KASAN support, which
  broke booting on machines with "bootx" early debugging enabled.

  A fix for a bug which broke kexec on 32-bit, introduced by changes to
  the 32-bit STRICT_KERNEL_RWX support in v5.1.

  Finally two fixes going to stable for our THP split/collapse handling,
  discovered by Nick. The first fixes random crashes and/or corruption
  in guests under sufficient load.

  Thanks to: Nicholas Piggin, Christophe Leroy, Aaro Koskinen, Mathieu
  Malaterre"

* tag 'powerpc-5.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/32s: fix booting with CONFIG_PPC_EARLY_DEBUG_BOOTX
  powerpc/64s: __find_linux_pte() synchronization vs pmdp_invalidate()
  powerpc/64s: Fix THP PMD collapse serialisation
  powerpc: Fix kexec failure on book3s/32
2019-06-15 07:29:32 -10:00
Nicholas Piggin 33258a1db1 powerpc/64s: Fix THP PMD collapse serialisation
Commit 1b2443a547 ("powerpc/book3s64: Avoid multiple endian
conversion in pte helpers") changed the actual bitwise tests in
pte_access_permitted by using pte_write() and pte_present() helpers
rather than raw bitwise testing _PAGE_WRITE and _PAGE_PRESENT bits.

The pte_present() change now returns true for PTEs which are
!_PAGE_PRESENT and _PAGE_INVALID, which is the combination used by
pmdp_invalidate() to synchronize access from lock-free lookups.
pte_access_permitted() is used by pmd_access_permitted(), so allowing
GUP lock free access to proceed with such PTEs breaks this
synchronisation.

This bug has been observed on a host using the hash page table MMU,
with random crashes and corruption in guests, usually together with
bad PMD messages in the host.

Fix this by adding an explicit check in pmd_access_permitted(), and
documenting the condition explicitly.

The pte_write() change should be okay, and would prevent GUP from
falling back to the slow path when encountering savedwrite PTEs, which
matches what x86 (that does not implement savedwrite) does.

Fixes: 1b2443a547 ("powerpc/book3s64: Avoid multiple endian conversion in pte helpers")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-06-07 16:26:44 +10:00
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Linus Torvalds 86a78a8b8d powerpc fixes for 5.2 #2
One fix going back to stable, for a bug on 32-bit introduced when we added
 support for THREAD_INFO_IN_TASK.
 
 A fix for a typo in a recent rework of our hugetlb code that leads to crashes on
 64-bit when using hugetlbfs with a 4K PAGE_SIZE.
 
 Two fixes for our recent rework of the address layout on 64-bit hash CPUs, both
 only triggered when userspace tries to access addresses outside the user or
 kernel address ranges.
 
 Finally a fix for a recently introduced double free in an error path in our
 cacheinfo code.
 
 Thanks to:
   Aneesh Kumar K.V, Christophe Leroy, Sachin Sant, Tobin C. Harding.
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Merge tag 'powerpc-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "One fix going back to stable, for a bug on 32-bit introduced when we
  added support for THREAD_INFO_IN_TASK.

  A fix for a typo in a recent rework of our hugetlb code that leads to
  crashes on 64-bit when using hugetlbfs with a 4K PAGE_SIZE.

  Two fixes for our recent rework of the address layout on 64-bit hash
  CPUs, both only triggered when userspace tries to access addresses
  outside the user or kernel address ranges.

  Finally a fix for a recently introduced double free in an error path
  in our cacheinfo code.

  Thanks to: Aneesh Kumar K.V, Christophe Leroy, Sachin Sant, Tobin C.
  Harding"

* tag 'powerpc-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/cacheinfo: Remove double free
  powerpc/mm/hash: Fix get_region_id() for invalid addresses
  powerpc/mm: Drop VM_BUG_ON in get_region_id()
  powerpc/mm: Fix crashes with hugepages & 4K pages
  powerpc/32s: fix flush_hash_pages() on SMP
2019-05-19 10:10:15 -07:00
Aneesh Kumar K.V c179976cf4 powerpc/mm/hash: Fix get_region_id() for invalid addresses
Accesses by userspace to random addresses outside the user or kernel
address range will generate an SLB fault. When we handle that fault we
classify the effective address into several classes, eg. user, kernel
linear, kernel virtual etc.

For addresses that are completely outside of any valid range, we
should not insert an SLB entry at all, and instead immediately an
exception.

In the past this was handled in two ways. Firstly we would check the
top nibble of the address (using REGION_ID(ea)) and that would tell us
if the address was user (0), kernel linear (c), kernel virtual (d), or
vmemmap (f). If the address didn't match any of these it was invalid.

Then for each type of address we would do a secondary check. For the
user region we check against H_PGTABLE_RANGE, for kernel linear we
would mask the top nibble of the address and then check the address
against MAX_PHYSMEM_BITS.

As part of commit 0034d395f8 ("powerpc/mm/hash64: Map all the kernel
regions in the same 0xc range") we replaced REGION_ID() with
get_region_id() and changed the masking of the top nibble to only mask
the top two bits, which introduced a bug.

Addresses less than (4 << 60) are still handled correctly, they are
either less than (1 << 60) in which case they are subject to the
H_PGTABLE_RANGE check, or they are correctly checked against
MAX_PHYSMEM_BITS.

However addresses from (4 << 60) to ((0xc << 60) - 1), are incorrectly
treated as kernel linear addresses in get_region_id(). Then the top
two bits are cleared by EA_MASK in slb_allocate_kernel() and the
address is checked against MAX_PHYSMEM_BITS, which it passes due to
the masking. The end result is we incorrectly insert SLB entries for
those addresses.

That is not actually catastrophic, having inserted the SLB entry we
will then go on to take a page fault for the address and at that point
we detect the problem and report it as a bad fault.

Still we should not be inserting those entries, or treating them as
kernel linear addresses in the first place. So fix get_region_id() to
detect addresses in that range and return an invalid region id, which
we cause use to not insert an SLB entry and directly report an
exception.

Fixes: 0034d395f8 ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Drop change to EA_MASK for now, rewrite change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-17 22:57:40 +10:00
Aneesh Kumar K.V 6457f42eb3 powerpc/mm: Drop VM_BUG_ON in get_region_id()
We call get_region_id() without validating the ea value. That means
with a wrong ea value we hit the BUG as below.

  kernel BUG at arch/powerpc/include/asm/book3s/64/hash.h:129!
  Oops: Exception in kernel mode, sig: 5 [#1]
  LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
  CPU: 0 PID: 3937 Comm: access_tests Not tainted 5.1.0
  ....
  NIP [c00000000007ba20] do_slb_fault+0x70/0x320
  LR [c00000000000896c] data_access_slb_common+0x15c/0x1a0

Fix this by removing the VM_BUG_ON. All callers make sure the returned
region id is valid and error out otherwise.

Fixes: 0034d395f8 ("powerpc/mm/hash64: Map all the kernel regions in the same 0xc range")
Reported-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-17 00:40:01 +10:00
Alexandre Ghiti 4eb0716e86 hugetlb: allow to free gigantic pages regardless of the configuration
On systems without CONTIG_ALLOC activated but that support gigantic pages,
boottime reserved gigantic pages can not be freed at all.  This patch
simply enables the possibility to hand back those pages to memory
allocator.

Link: http://lkml.kernel.org/r/20190327063626.18421-5-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Acked-by: David S. Miller <davem@davemloft.net> [sparc]
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:47 -07:00
Michael Ellerman 8150a153c0 powerpc/64s: Use early_mmu_has_feature() in set_kuap()
When implementing the KUAP support on Radix we fixed one case where
mmu_has_feature() was being called too early in boot via
__put_user_size().

However since then some new code in linux-next has created a new path
via which we can end up calling mmu_has_feature() too early.

On P9 this leads to crashes early in boot if we have both PPC_KUAP and
CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG enabled. Our early boot code
calls printk() which calls probe_kernel_read(), that does a
__copy_from_user_inatomic() which calls into set_kuap() and that uses
mmu_has_feature().

At that point in boot we haven't patched MMU features yet so the debug
code in mmu_has_feature() complains, and calls printk(). At that point
we recurse, eg:

  ...
  dump_stack+0xdc
  probe_kernel_read+0x1a4
  check_pointer+0x58
  ...
  printk+0x40
  dump_stack_print_info+0xbc
  dump_stack+0x8
  probe_kernel_read+0x1a4
  probe_kernel_read+0x19c
  check_pointer+0x58
  ...
  printk+0x40
  cpufeatures_process_feature+0xc8
  scan_cpufeatures_subnodes+0x380
  of_scan_flat_dt_subnodes+0xb4
  dt_cpu_ftrs_scan_callback+0x158
  of_scan_flat_dt+0xf0
  dt_cpu_ftrs_scan+0x3c
  early_init_devtree+0x360
  early_setup+0x9c

And so on for infinity, symptom is a dead system.

Even more fun is what happens when using the hash MMU (ie. p8 or p9
with Radix disabled), and when we don't have
CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG enabled. With the debug disabled
we don't check if static keys have been initialised, we just rely on
the jump label. But the jump label defaults to true so we just whack
the AMR even though Radix is not enabled.

Clearing the AMR is fine, but after we've done the user copy we write
(0b11 << 62) into AMR. When using hash that makes all pages with key
zero no longer readable or writable. All kernel pages implicitly have
key zero, and so all of a sudden the kernel can't read or write any of
its memory. Again dead system.

In the medium term we have several options for fixing this.
probe_kernel_read() doesn't need to touch AMR at all, it's not doing a
user access after all, but it uses __copy_from_user_inatomic() just
because it's easy, we could fix that.

It would also be safe to default to not writing to the AMR during
early boot, until we've detected features. But it's not clear that
flipping all the MMU features to static_key_false won't introduce
other bugs.

But for now just switch to early_mmu_has_feature() in set_kuap(), that
avoids all the problems with jump labels. It adds the overhead of a
global lookup and test, but that's probably trivial compared to the
writes to the AMR anyway.

Fixes: 890274c2dc ("powerpc/64s: Implement KUAP for Radix MMU")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Russell Currey <ruscur@russell.cc>
2019-05-09 14:28:56 +10:00
Rick Lindsley f39356261c powerpc/book3s/64: check for NULL pointer in pgd_alloc()
When the memset code was added to pgd_alloc(), it failed to consider
that kmem_cache_alloc() can return NULL. It's uncommon, but not
impossible under heavy memory contention. Example oops:

  Unable to handle kernel paging request for data at address 0x00000000
  Faulting instruction address: 0xc0000000000a4000
  Oops: Kernel access of bad area, sig: 11 [#1]
  LE SMP NR_CPUS=2048 NUMA pSeries
  CPU: 70 PID: 48471 Comm: entrypoint.sh Kdump: loaded Not tainted 4.14.0-115.6.1.el7a.ppc64le #1
  task: c000000334a00000 task.stack: c000000331c00000
  NIP:  c0000000000a4000 LR: c00000000012f43c CTR: 0000000000000020
  REGS: c000000331c039c0 TRAP: 0300   Not tainted  (4.14.0-115.6.1.el7a.ppc64le)
  MSR:  800000010280b033 <SF,VEC,VSX,EE,FP,ME,IR,DR,RI,LE,TM[E]>  CR: 44022840  XER: 20040000
  CFAR: c000000000008874 DAR: 0000000000000000 DSISR: 42000000 SOFTE: 1
  ...
  NIP [c0000000000a4000] memset+0x68/0x104
  LR [c00000000012f43c] mm_init+0x27c/0x2f0
  Call Trace:
    mm_init+0x260/0x2f0 (unreliable)
    copy_mm+0x11c/0x638
    copy_process.isra.28.part.29+0x6fc/0x1080
    _do_fork+0xdc/0x4c0
    ppc_clone+0x8/0xc
  Instruction dump:
  409e000c b0860000 38c60002 409d000c 90860000 38c60004 78a0d183 78a506a0
  7c0903a6 41820034 60000000 60420000 <f8860000> f8860008 f8860010 f8860018

Fixes: fc5c2f4a55 ("powerpc/mm/hash64: Zero PGD pages on allocation")
Cc: stable@vger.kernel.org # v4.16+
Signed-off-by: Rick Lindsley <ricklind@vnet.linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-07 13:24:31 +10:00
Christophe Leroy a67beca077 powerpc/32: make KVIRT_TOP dependent on FIXMAP_START
When we add KASAN shadow area, KVIRT_TOP can't be anymore fixed
at 0xfe000000.

This patch uses FIXADDR_START to define KVIRT_TOP.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:26 +10:00
Christophe Leroy 8a2cc87a24 powerpc/mm: refactor pmd_pgtable()
pmd_pgtable() is identical on the 4 subarches, refactor it.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:25 +10:00
Christophe Leroy e80789a3c1 powerpc/mm: refactor definition of pgtable_cache[]
pgtable_cache[] is the same for the 4 subarches, lets make it common.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:25 +10:00
Christophe Leroy dc096864ba powerpc/mm: refactor pte_alloc_one() and pte_free() families definition.
Functions pte_alloc_one(), pte_alloc_one_kernel(), pte_free(),
pte_free_kernel() are identical for the four subarches.

This patch moves their definition in a common place.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:25 +10:00
Christophe Leroy b0124ff57e powerpc/mm: inline pte_alloc_one_kernel() and pte_alloc_one() on PPC32
pte_alloc_one_kernel() and pte_alloc_one() are simple calls to
pte_fragment_alloc(), so they are good candidates for inlining as
already done on PPC64.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:25 +10:00
Christophe Leroy 696dffa24b powerpc/mm: move pgtable_t in asm/mmu.h
pgtable_t is now identical for all subarches, move it to the
top level asm/mmu.h

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:24 +10:00
Christophe Leroy 447def3b06 powerpc/mm: drop __bad_pte()
This has never been called (since Kernel has been in git at least),
drop it.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:24 +10:00
Christophe Leroy 723f268f19 powerpc/mm: cleanup ifdef mess in add_huge_page_size()
Introduce a subarch specific helper check_and_get_huge_psize()
to check the huge page sizes and cleanup the ifdef mess in
add_huge_page_size()

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:23 +10:00
Christophe Leroy 5fb84fec46 powerpc/mm: add a helper to populate hugepd
This patchs adds a subarch helper to populate hugepd.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:23 +10:00
Christophe Leroy 8197af22be powerpc/mm: split asm/hugetlb.h into dedicated subarch files
Three subarches support hugepages:
  - fsl book3e
  - book3s/64
  - 8xx

This patch splits asm/hugetlb.h to reduce the #ifdef mess.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:23 +10:00
Christophe Leroy 5953fb4f46 powerpc/mm: define subarch SLB_ADDR_LIMIT_DEFAULT
This patch defines a subarch specific SLB_ADDR_LIMIT_DEFAULT
to remove the #ifdefs around the setup of mm->context.slb_addr_limit

It also generalises the use of mm_ctx_set_slb_addr_limit() helper.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:23 +10:00
Christophe Leroy 877461210e powerpc/mm: get rid of mm_ctx_slice_mask_xxx()
Now that slice_mask_for_size() is in mmu.h, the mm_ctx_slice_mask_xxx()
are not needed anymore, so drop them. Note that the 8xx ones where
not used anyway.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:22 +10:00
Christophe Leroy fca5c1e9eb powerpc/mm: move slice_mask_for_size() into mmu.h
Move slice_mask_for_size() into subarch mmu.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
[mpe: Retain the BUG_ON()s, rather than converting to VM_BUG_ON()]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:22 +10:00
Aneesh Kumar K.V 5f53d28608 powerpc/mm/hash: Rename KERNEL_REGION_ID to LINEAR_MAP_REGION_ID
The region actually point to linear map. Rename the #define to
clarify thati.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:40 +10:00
Aneesh Kumar K.V 1c946c1b7f powerpc/mm/hash: Simplify the region id calculation.
This reduces multiple comparisons in get_region_id to a bit shift operation.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:40 +10:00
Aneesh Kumar K.V 0034d395f8 powerpc/mm/hash64: Map all the kernel regions in the same 0xc range
This patch maps vmalloc, IO and vmemap regions in the 0xc address range
instead of the current 0xd and 0xf range. This brings the mapping closer
to radix translation mode.

With hash 64K page size each of this region is 512TB whereas with 4K config
we are limited by the max page table range of 64TB and hence there regions
are of 16TB size.

The kernel mapping is now:

 On 4K hash

     kernel_region_map_size = 16TB
     kernel vmalloc start   = 0xc000100000000000
     kernel IO start        = 0xc000200000000000
     kernel vmemmap start   = 0xc000300000000000

64K hash, 64K radix and 4k radix:

     kernel_region_map_size = 512TB
     kernel vmalloc start   = 0xc008000000000000
     kernel IO start        = 0xc00a000000000000
     kernel vmemmap start   = 0xc00c000000000000

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Aneesh Kumar K.V a35a3c6f60 powerpc/mm/hash64: Add a variable to track the end of IO mapping
This makes it easy to update the region mapping in the later patch

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Aneesh Kumar K.V ef629cc5bf powerc/mm/hash: Reduce hash_mm_context size
Allocate subpage protect related variables only if we use the feature.
This helps in reducing the hash related mm context struct by around 4K

Before the patch
sizeof(struct hash_mm_context)  = 8288

After the patch
sizeof(struct hash_mm_context) = 4160

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Aneesh Kumar K.V 701101865f powerpc/mm: Reduce memory usage for mm_context_t for radix
Currently, our mm_context_t on book3s64 include all hash specific
context details like slice mask and subpage protection details. We
can skip allocating these with radix translation. This will help us to save
8K per mm_context with radix translation.

With the patch applied we have

sizeof(mm_context_t)  = 136
sizeof(struct hash_mm_context)  = 8288

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:39 +10:00
Aneesh Kumar K.V 60458fba46 powerpc/mm: Add helpers for accessing hash translation related variables
We want to switch to allocating them runtime only when hash translation is
enabled. Add helpers so that both book3s and nohash can be adapted to
upcoming change easily.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:38 +10:00
Aneesh Kumar K.V 4f40b15f33 powerpc/mm: Remove PPC_MM_SLICES #ifdef for book3s64
Book3s64 always have PPC_MM_SLICES enabled. So remove the unncessary #ifdef

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:38 +10:00
Aneesh Kumar K.V 6161a37307 powerpc/mm: Fix build error with FLATMEM book3s64 config
The current value of MAX_PHYSMEM_BITS cannot work with 32 bit configs.
We used to have MAX_PHYSMEM_BITS not defined without SPARSEMEM and 32
bit configs never expected a value to be set for MAX_PHYSMEM_BITS.

Dependent code such as zsmalloc derived the right values based on other
fields. Instead of finding a value that works with different configs,
use new values only for book3s_64. For 64 bit booke, use the definition
of MAX_PHYSMEM_BITS as per commit a7df61a0e2 ("[PATCH] ppc64: Increase sparsemem defaults")
That change was done in 2005 and hopefully will work with book3e 64.

Fixes: 8bc0868998 ("powerpc/mm: Only define MAX_PHYSMEM_BITS in SPARSEMEM configurations")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:12:38 +10:00
Christophe Leroy a68c31fc01 powerpc/32s: Implement Kernel Userspace Access Protection
This patch implements Kernel Userspace Access Protection for
book3s/32.

Due to limitations of the processor page protection capabilities,
the protection is only against writing. read protection cannot be
achieved using page protection.

The previous patch modifies the page protection so that RW user
pages are RW for Key 0 and RO for Key 1, and it sets Key 0 for
both user and kernel.

This patch changes userspace segment registers are set to Ku 0
and Ks 1. When kernel needs to write to RW pages, the associated
segment register is then changed to Ks 0 in order to allow write
access to the kernel.

In order to avoid having the read all segment registers when
locking/unlocking the access, some data is kept in the thread_struct
and saved on stack on exceptions. The field identifies both the
first unlocked segment and the first segment following the last
unlocked one. When no segment is unlocked, it contains value 0.

As the hash_page() function is not able to easily determine if a
protfault is due to a bad kernel access to userspace, protfaults
need to be handled by handle_page_fault when KUAP is set.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Drop allow_read/write_to/from_user() as they're now in kup.h,
      and adapt allow_user_access() to do nothing when to == NULL]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:11:47 +10:00
Christophe Leroy f342adca3a powerpc/32s: Prepare Kernel Userspace Access Protection
This patch prepares Kernel Userspace Access Protection for
book3s/32.

Due to limitations of the processor page protection capabilities,
the protection is only against writing. read protection cannot be
achieved using page protection.

book3s/32 provides the following values for PP bits:

PP00 provides RW for Key 0 and NA for Key 1
PP01 provides RW for Key 0 and RO for Key 1
PP10 provides RW for all
PP11 provides RO for all

Today PP10 is used for RW pages and PP11 for RO pages, and user
segment register's Kp and Ks are set to 1. This patch modifies
page protection to use PP01 for RW pages and sets user segment
registers to Kp 0 and Ks 0.

This will allow to setup Userspace write access protection by
settng Ks to 1 in the following patch.

Kernel space segment registers remain unchanged.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:11:46 +10:00
Christophe Leroy 31ed2b13c4 powerpc/32s: Implement Kernel Userspace Execution Prevention.
To implement Kernel Userspace Execution Prevention, this patch
sets NX bit on all user segments on kernel entry and clears NX bit
on all user segments on kernel exit.

Note that powerpc 601 doesn't have the NX bit, so KUEP will not
work on it. A warning is displayed at startup.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:11:46 +10:00
Michael Ellerman 5e5be3aed2 powerpc/mm: Detect bad KUAP faults
When KUAP is enabled we have logic to detect page faults that occur
outside of a valid user access region and are blocked by the AMR.

What we don't have at the moment is logic to detect a fault *within* a
valid user access region, that has been incorrectly blocked by AMR.
This is not meant to ever happen, but it can if we incorrectly
save/restore the AMR, or if the AMR was overwritten for some other
reason.

Currently if that happens we assume it's just a regular fault that
will be corrected by handling the fault normally, so we just return.
But there is nothing the fault handling code can do to fix it, so the
fault just happens again and we spin forever, leading to soft lockups.

So add some logic to detect that case and WARN() if we ever see it.
Arguably it should be a BUG(), but it's more polite to fail the access
and let the kernel continue, rather than taking down the box. There
should be no data integrity issue with failing the fault rather than
BUG'ing, as we're just going to disallow an access that should have
been allowed.

To make the code a little easier to follow, unroll the condition at
the end of bad_kernel_fault() and comment each case, before adding the
call to bad_kuap_fault().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:06:04 +10:00
Michael Ellerman 890274c2dc powerpc/64s: Implement KUAP for Radix MMU
Kernel Userspace Access Prevention utilises a feature of the Radix MMU
which disallows read and write access to userspace addresses. By
utilising this, the kernel is prevented from accessing user data from
outside of trusted paths that perform proper safety checks, such as
copy_{to/from}_user() and friends.

Userspace access is disabled from early boot and is only enabled when
performing an operation like copy_{to/from}_user(). The register that
controls this (AMR) does not prevent userspace from accessing itself,
so there is no need to save and restore when entering and exiting
userspace.

When entering the kernel from the kernel we save AMR and if it is not
blocking user access (because eg. we faulted doing a user access) we
reblock user access for the duration of the exception (ie. the page
fault) and then restore the AMR when returning back to the kernel.

This feature can be tested by using the lkdtm driver (CONFIG_LKDTM=y)
and performing the following:

  # (echo ACCESS_USERSPACE) > [debugfs]/provoke-crash/DIRECT

If enabled, this should send SIGSEGV to the thread.

We also add paranoid checking of AMR in switch and syscall return
under CONFIG_PPC_KUAP_DEBUG.

Co-authored-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Russell Currey <ruscur@russell.cc>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21 23:06:02 +10:00
Qian Cai bff25143da powerpc/mm: Silence unused-but-set-variable warnings
pte_unmap() compiles away on some powerpc platforms, so silence the
warnings below by making it a static inline function.

  mm/memory.c: In function 'copy_pte_range':
  mm/memory.c:820:24: warning: variable 'orig_dst_pte' set but not used
  mm/memory.c:820:9: warning: variable 'orig_src_pte' set but not used
  mm/madvise.c: In function 'madvise_free_pte_range':
  mm/madvise.c:318:9: warning: variable 'orig_pte' set but not used
  mm/swap_state.c: In function 'swap_ra_info':
  mm/swap_state.c:634:15: warning: variable 'orig_pte' set but not used

Suggested-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Qian Cai <cai@lca.pw>
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-20 22:02:26 +10:00
Michael Ellerman eea86aa417 powerpc/mm/64: Document the sizes of/sizes mapped by Pxx_INDEX_SIZE
Add comments describing the size in bytes of the various levels of the
page table tree, and the size of the virtual address space mapped by
each level, to make it clear what the sizes are without having to also
look up other definitions.

The code that calculates the sizes actually uses sizeof(pgd_t) etc.,
so in theory these comments could skew vs the code, but the size of
pgd_t etc. is unlikely to change very often.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-20 22:02:11 +10:00
Linus Torvalds a9c55d58bc powerpc fixes for 5.1 #2
One fix to prevent runtime allocation of 16GB pages when running in a VM (as
 opposed to bare metal), because it doesn't work.
 
 A small fix to our recently added KCOV support to exempt some more code from
 being instrumented.
 
 Plus a few minor build fixes, a small dead code removal and a defconfig update.
 
 Thanks to:
   Alexey Kardashevskiy, Aneesh Kumar K.V, Christophe Leroy, Jason Yan, Joel
   Stanley, Mahesh Salgaonkar, Mathieu Malaterre.
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Merge tag 'powerpc-5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fixes from Michael Ellerman:
 "One fix to prevent runtime allocation of 16GB pages when running in a
  VM (as opposed to bare metal), because it doesn't work.

  A small fix to our recently added KCOV support to exempt some more
  code from being instrumented.

  Plus a few minor build fixes, a small dead code removal and a
  defconfig update.

  Thanks to: Alexey Kardashevskiy, Aneesh Kumar K.V, Christophe Leroy,
  Jason Yan, Joel Stanley, Mahesh Salgaonkar, Mathieu Malaterre"

* tag 'powerpc-5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Include <asm/nmi.h> header file to fix a warning
  powerpc/powernv: Fix compile without CONFIG_TRACEPOINTS
  powerpc/mm: Disable kcov for SLB routines
  powerpc: remove dead code in head_fsl_booke.S
  powerpc/configs: Sync skiroot defconfig
  powerpc/hugetlb: Don't do runtime allocation of 16G pages in LPAR configuration
2019-03-16 10:45:17 -07:00
Linus Torvalds 6c3ac11343 powerpc updates for 5.1
Notable changes:
 
  - Enable THREAD_INFO_IN_TASK to move thread_info off the stack.
 
  - A big series from Christoph reworking our DMA code to use more of the generic
    infrastructure, as he said:
    "This series switches the powerpc port to use the generic swiotlb and
     noncoherent dma ops, and to use more generic code for the coherent direct
     mapping, as well as removing a lot of dead code."
 
  - Increase our vmalloc space to 512T with the Hash MMU on modern CPUs, allowing
    us to support machines with larger amounts of total RAM or distance between
    nodes.
 
  - Two series from Christophe, one to optimise TLB miss handlers on 6xx, and
    another to optimise the way STRICT_KERNEL_RWX is implemented on some 32-bit
    CPUs.
 
  - Support for KCOV coverage instrumentation which means we can run syzkaller
    and discover even more bugs in our code.
 
 And as always many clean-ups, reworks and minor fixes etc.
 
 Thanks to:
  Alan Modra, Alexey Kardashevskiy, Alistair Popple, Andrea Arcangeli, Andrew
  Donnellan, Aneesh Kumar K.V, Aravinda Prasad, Balbir Singh, Brajeswar Ghosh,
  Breno Leitao, Christian Lamparter, Christian Zigotzky, Christophe Leroy,
  Christoph Hellwig, Corentin Labbe, Daniel Axtens, David Gibson, Diana Craciun,
  Firoz Khan, Gustavo A. R. Silva, Igor Stoppa, Joe Lawrence, Joel Stanley,
  Jonathan Neuschäfer, Jordan Niethe, Laurent Dufour, Madhavan Srinivasan, Mahesh
  Salgaonkar, Mark Cave-Ayland, Masahiro Yamada, Mathieu Malaterre, Matteo Croce,
  Meelis Roos, Michael W. Bringmann, Nathan Chancellor, Nathan Fontenot, Nicholas
  Piggin, Nick Desaulniers, Nicolai Stange, Oliver O'Halloran, Paul Mackerras,
  Peter Xu, PrasannaKumar Muralidharan, Qian Cai, Rashmica Gupta, Reza Arbab,
  Robert P. J. Day, Russell Currey, Sabyasachi Gupta, Sam Bobroff, Sandipan Das,
  Sergey Senozhatsky, Souptick Joarder, Stewart Smith, Tyrel Datwyler, Vaibhav
  Jain, YueHaibing.
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Merge tag 'powerpc-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Notable changes:

   - Enable THREAD_INFO_IN_TASK to move thread_info off the stack.

   - A big series from Christoph reworking our DMA code to use more of
     the generic infrastructure, as he said:
       "This series switches the powerpc port to use the generic swiotlb
        and noncoherent dma ops, and to use more generic code for the
        coherent direct mapping, as well as removing a lot of dead
        code."

   - Increase our vmalloc space to 512T with the Hash MMU on modern
     CPUs, allowing us to support machines with larger amounts of total
     RAM or distance between nodes.

   - Two series from Christophe, one to optimise TLB miss handlers on
     6xx, and another to optimise the way STRICT_KERNEL_RWX is
     implemented on some 32-bit CPUs.

   - Support for KCOV coverage instrumentation which means we can run
     syzkaller and discover even more bugs in our code.

  And as always many clean-ups, reworks and minor fixes etc.

  Thanks to: Alan Modra, Alexey Kardashevskiy, Alistair Popple, Andrea
  Arcangeli, Andrew Donnellan, Aneesh Kumar K.V, Aravinda Prasad, Balbir
  Singh, Brajeswar Ghosh, Breno Leitao, Christian Lamparter, Christian
  Zigotzky, Christophe Leroy, Christoph Hellwig, Corentin Labbe, Daniel
  Axtens, David Gibson, Diana Craciun, Firoz Khan, Gustavo A. R. Silva,
  Igor Stoppa, Joe Lawrence, Joel Stanley, Jonathan Neuschäfer, Jordan
  Niethe, Laurent Dufour, Madhavan Srinivasan, Mahesh Salgaonkar, Mark
  Cave-Ayland, Masahiro Yamada, Mathieu Malaterre, Matteo Croce, Meelis
  Roos, Michael W. Bringmann, Nathan Chancellor, Nathan Fontenot,
  Nicholas Piggin, Nick Desaulniers, Nicolai Stange, Oliver O'Halloran,
  Paul Mackerras, Peter Xu, PrasannaKumar Muralidharan, Qian Cai,
  Rashmica Gupta, Reza Arbab, Robert P. J. Day, Russell Currey,
  Sabyasachi Gupta, Sam Bobroff, Sandipan Das, Sergey Senozhatsky,
  Souptick Joarder, Stewart Smith, Tyrel Datwyler, Vaibhav Jain,
  YueHaibing"

* tag 'powerpc-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (200 commits)
  powerpc/32: Clear on-stack exception marker upon exception return
  powerpc: Remove export of save_stack_trace_tsk_reliable()
  powerpc/mm: fix "section_base" set but not used
  powerpc/mm: Fix "sz" set but not used warning
  powerpc/mm: Check secondary hash page table
  powerpc: remove nargs from __SYSCALL
  powerpc/64s: Fix unrelocated interrupt trampoline address test
  powerpc/powernv/ioda: Fix locked_vm counting for memory used by IOMMU tables
  powerpc/fsl: Fix the flush of branch predictor.
  powerpc/powernv: Make opal log only readable by root
  powerpc/xmon: Fix opcode being uninitialized in print_insn_powerpc
  powerpc/powernv: move OPAL call wrapper tracing and interrupt handling to C
  powerpc/64s: Fix data interrupts vs d-side MCE reentrancy
  powerpc/64s: Prepare to handle data interrupts vs d-side MCE reentrancy
  powerpc/64s: system reset interrupt preserve HSRRs
  powerpc/64s: Fix HV NMI vs HV interrupt recoverability test
  powerpc/mm/hash: Handle mmap_min_addr correctly in get_unmapped_area topdown search
  powerpc/hugetlb: Handle mmap_min_addr correctly in get_unmapped_area callback
  selftests/powerpc: Remove duplicate header
  powerpc sstep: Add support for modsd, modud instructions
  ...
2019-03-07 12:56:26 -08:00
Aneesh Kumar K.V 8ef5cbde6d arch/powerpc/mm/hugetlb: NestMMU workaround for hugetlb mprotect RW upgrade
NestMMU requires us to mark the pte invalid and flush the tlb when we do
a RW upgrade of pte.  We fixed a variant of this in the fault path in
bd5050e38a ("powerpc/mm/radix: Change pte relax sequence to handle
nest MMU hang").

Link: http://lkml.kernel.org/r/20190116085035.29729-6-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:18 -08:00
Aneesh Kumar K.V 5b323367ef arch/powerpc/mm: Nest MMU workaround for mprotect RW upgrade
NestMMU requires us to mark the pte invalid and flush the tlb when we do
a RW upgrade of pte.  We fixed a variant of this in the fault path in
bd5050e38a ("powerpc/mm/radix: Change pte relax sequence to handle
nest MMU hang").

Do the same for mprotect upgrades.

Hugetlb is handled in the next patch.

Link: http://lkml.kernel.org/r/20190116085035.29729-4-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-03-05 21:07:18 -08:00