linux.git/arch/csky, branch v6.12

mm: make arch_get_unmapped_area() take vm_flags by default

2024-09-09T23:39:13+00:00

Patch series "mm: Care about shadow stack guard gap when getting an
unmapped area", v2.

As covered in the commit log for c44357c2e76b ("x86/mm: care about shadow
stack guard gap during placement") our current mmap() implementation does
not take care to ensure that a new mapping isn't placed with existing
mappings inside it's own guard gaps.  This is particularly important for
shadow stacks since if two shadow stacks end up getting placed adjacent to
each other then they can overflow into each other which weakens the
protection offered by the feature.

On x86 there is a custom arch_get_unmapped_area() which was updated by the
above commit to cover this case by specifying a start_gap for allocations
with VM_SHADOW_STACK.  Both arm64 and RISC-V have equivalent features and
use the generic implementation of arch_get_unmapped_area() so let's make
the equivalent change there so they also don't get shadow stack pages
placed without guard pages.  The arm64 and RISC-V shadow stack
implementations are currently on the list:

   https://lore.kernel.org/r/20240829-arm64-gcs-v12-0-42fec94743
   https://lore.kernel.org/lkml/20240403234054.2020347-1-debug@rivosinc.com/

Given the addition of the use of vm_flags in the generic implementation we
also simplify the set of possibilities that have to be dealt with in the
core code by making arch_get_unmapped_area() take vm_flags as standard. 
This is a bit invasive since the prototype change touches quite a few
architectures but since the parameter is ignored the change is
straightforward, the simplification for the generic code seems worth it.


This patch (of 3):

When we introduced arch_get_unmapped_area_vmflags() in 961148704acd ("mm:
introduce arch_get_unmapped_area_vmflags()") we did so as part of properly
supporting guard pages for shadow stacks on x86_64, which uses a custom
arch_get_unmapped_area().  Equivalent features are also present on both
arm64 and RISC-V, both of which use the generic implementation of
arch_get_unmapped_area() and will require equivalent modification there. 
Rather than continue to deal with having two versions of the functions
let's bite the bullet and have all implementations of
arch_get_unmapped_area() take vm_flags as a parameter.

The new parameter is currently ignored by all implementations other than
x86.  The only caller that doesn't have a vm_flags available is
mm_get_unmapped_area(), as for the x86 implementation and the wrapper used
on other architectures this is modified to supply no flags.

No functional changes.

Link: https://lkml.kernel.org/r/20240904-mm-generic-shadow-stack-guard-v2-0-a46b8b6dc0ed@kernel.org
Link: https://lkml.kernel.org/r/20240904-mm-generic-shadow-stack-guard-v2-1-a46b8b6dc0ed@kernel.org
Signed-off-by: Mark Brown 
Acked-by: Lorenzo Stoakes 
Reviewed-by: Liam R. Howlett 
Acked-by: Helge Deller 	[parisc]
Cc: Alexander Gordeev 
Cc: Andreas Larsson 
Cc: Borislav Petkov 
Cc: Christian Borntraeger 
Cc: Christophe Leroy 
Cc: Chris Zankel 
Cc: Dave Hansen 
Cc: David S. Miller 
Cc: "Edgecombe, Rick P" 
Cc: Gerald Schaefer 
Cc: Guo Ren 
Cc: Heiko Carstens 
Cc: "H. Peter Anvin" 
Cc: Huacai Chen 
Cc: Ingo Molnar 
Cc: Ivan Kokshaysky 
Cc: James Bottomley 
Cc: John Paul Adrian Glaubitz 
Cc: Matt Turner 
Cc: Max Filippov 
Cc: Michael Ellerman 
Cc: Naveen N Rao 
Cc: Nicholas Piggin 
Cc: Richard Henderson 
Cc: Rich Felker 
Cc: Russell King 
Cc: Sven Schnelle 
Cc: Thomas Bogendoerfer 
Cc: Thomas Gleixner 
Cc: Vasily Gorbik 
Cc: Vineet Gupta 
Cc: Vlastimil Babka 
Cc: WANG Xuerui 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

mm: remove legacy install_special_mapping() code

2024-09-02T03:26:13+00:00

All relevant architectures had already been converted to the new interface
(which just has an underscore in front of the name - not very imaginative
naming), this just force-converts the stragglers.

The modern interface is almost identical to the old one, except instead of
the page pointer it takes a "struct vm_special_mapping" that describes the
mapping (and contains the page pointer as one member), and it returns the
resulting 'vma' instead of just the error code.

Getting rid of the old interface also gets rid of some special casing,
which had caused problems with the mremap extensions to "struct
vm_special_mapping".

[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/CAHk-=whvR+z=0=0gzgdfUiK70JTa-=+9vxD-4T=3BagXR6dciA@mail.gmail.comTested-by: Rob Landley  # arch/sh/
Link: https://lore.kernel.org/all/20240819195120.GA1113263@thelio-3990X/
Signed-off-by: Linus Torvalds 
Cc: Nathan Chancellor 
Cc: Michael Ellerman 
Cc: Anton Ivanov 
Cc: Brian Cain 
Cc: Christophe Leroy 
Cc: Dinh Nguyen 
Cc: Guo Ren 
Cc: Jeff Xu 
Cc: Johannes Berg 
Cc: John Paul Adrian Glaubitz 
Cc: Liam R. Howlett 
Cc: Nicholas Piggin 
Cc: Pedro Falcato 
Cc: Richard Weinberger 
Cc: Rich Felker 
Cc: Rob Landley 
Cc: Yoshinori Sato 
Signed-off-by: Andrew Morton

Merge tag 'ftrace-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

2024-07-18T20:36:33+00:00

Pull ftrace updates from Steven Rostedt:
 "Rewrite of function graph tracer to allow multiple users

  Up until now, the function graph tracer could only have a single user
  attached to it. If another user tried to attach to the function graph
  tracer while one was already attached, it would fail. Allowing
  function graph tracer to have more than one user has been asked for
  since 2009, but it required a rewrite to the logic to pull it off so
  it never happened. Until now!

  There's three systems that trace the return of a function. That is
  kretprobes, function graph tracer, and BPF. kretprobes and function
  graph tracing both do it similarly. The difference is that kretprobes
  uses a shadow stack per callback and function graph tracer creates a
  shadow stack for all tasks. The function graph tracer method makes it
  possible to trace the return of all functions. As kretprobes now needs
  that feature too, allowing it to use function graph tracer was needed.
  BPF also wants to trace the return of many probes and its method
  doesn't scale either. Having it use function graph tracer would
  improve that.

  By allowing function graph tracer to have multiple users allows both
  kretprobes and BPF to use function graph tracer in these cases. This
  will allow kretprobes code to be removed in the future as it's version
  will no longer be needed.

  Note, function graph tracer is only limited to 16 simultaneous users,
  due to shadow stack size and allocated slots"

* tag 'ftrace-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (49 commits)
  fgraph: Use str_plural() in test_graph_storage_single()
  function_graph: Add READ_ONCE() when accessing fgraph_array[]
  ftrace: Add missing kerneldoc parameters to unregister_ftrace_direct()
  function_graph: Everyone uses HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, remove it
  function_graph: Fix up ftrace_graph_ret_addr()
  function_graph: Make fgraph_update_pid_func() a stub for !DYNAMIC_FTRACE
  function_graph: Rename BYTE_NUMBER to CHAR_NUMBER in selftests
  fgraph: Remove some unused functions
  ftrace: Hide one more entry in stack trace when ftrace_pid is enabled
  function_graph: Do not update pid func if CONFIG_DYNAMIC_FTRACE not enabled
  function_graph: Make fgraph_do_direct static key static
  ftrace: Fix prototypes for ftrace_startup/shutdown_subops()
  ftrace: Assign RCU list variable with rcu_assign_ptr()
  ftrace: Assign ftrace_list_end to ftrace_ops_list type cast to RCU
  ftrace: Declare function_trace_op in header to quiet sparse warning
  ftrace: Add comments to ftrace_hash_move() and friends
  ftrace: Convert "inc" parameter to bool in ftrace_hash_rec_update_modify()
  ftrace: Add comments to ftrace_hash_rec_disable/enable()
  ftrace: Remove "filter_hash" parameter from __ftrace_hash_rec_update()
  ftrace: Rename dup_hash() and comment it
  ...

csky: convert to generic syscall table

2024-07-10T12:23:38+00:00

The uapi/asm/unistd_32.h and asm/syscall_table_32.h headers can now be
generated from scripts/syscall.tbl, which makes this consistent with
the other architectures that have their own syscall.tbl.

csky has two architecture specific system calls, which I add to
the generic table.  The time32, stat64 and rlimit entries in the
syscall_abis_32 line are for system calls that were part of the generic
ABI when arch/csky got added but are no longer enabled by default for
new architectures.

Both the user visible side of asm/unistd.h and the internal syscall
table in the kernel should have the same effective contents after this.

Signed-off-by: Arnd Bergmann

clone3: drop __ARCH_WANT_SYS_CLONE3 macro

2024-07-10T12:23:38+00:00

When clone3() was introduced, it was not obvious how each architecture
deals with setting up the stack and keeping the register contents in
a fork()-like system call, so this was left for the architecture
maintainers to implement, with __ARCH_WANT_SYS_CLONE3 defined by those
that already implement it.

Five years later, we still have a few architectures left that are missing
clone3(), and the macro keeps getting in the way as it's fundamentally
different from all the other __ARCH_WANT_SYS_* macros that are meant
to provide backwards-compatibility with applications using older
syscalls that are no longer provided by default.

Address this by reversing the polarity of the macro, adding an
__ARCH_BROKEN_SYS_CLONE3 macro to all architectures that don't
already provide the syscall, and remove __ARCH_WANT_SYS_CLONE3
from all the other ones.

Acked-by: Geert Uytterhoeven 
Signed-off-by: Arnd Bergmann

csky: drop asm/gpio.h wrapper

2024-07-10T12:20:50+00:00

The asm/gpio.h header is gone now that all architectures just use
gpiolib, and so the redirect is no longer valid.

Acked-by: Guo Ren 
Signed-off-by: Arnd Bergmann

syscalls: mmap(): use unsigned offset type consistently

2024-06-25T13:57:38+00:00

Most architectures that implement the old-style mmap() with byte offset
use 'unsigned long' as the type for that offset, but microblaze and
riscv have the off_t type that is shared with userspace, matching the
prototype in include/asm-generic/syscalls.h.

Make this consistent by using an unsigned argument everywhere. This
changes the behavior slightly, as the argument is shifted to a page
number, and an user input with the top bit set would result in a
negative page offset rather than a large one as we use elsewhere.

For riscv, the 32-bit sys_mmap2() definition actually used a custom
type that is different from the global declaration, but this was
missed due to an incorrect type check.

Signed-off-by: Arnd Bergmann

csky, hexagon: fix broken sys_sync_file_range

2024-06-25T13:57:37+00:00

Both of these architectures require u64 function arguments to be
passed in even/odd pairs of registers or stack slots, which in case of
sync_file_range would result in a seven-argument system call that is
not currently possible. The system call is therefore incompatible with
all existing binaries.

While it would be possible to implement support for seven arguments
like on mips, it seems better to use a six-argument version, either
with the normal argument order but misaligned as on most architectures
or with the reordered sync_file_range2() calling conventions as on
arm and powerpc.

Cc: stable@vger.kernel.org
Acked-by: Guo Ren 
Signed-off-by: Arnd Bergmann

function_graph: Everyone uses HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, remove it

2024-06-11T15:18:24+00:00

All architectures that implement function graph also implements
HAVE_FUNCTION_GRAPH_RET_ADDR_PTR. Remove it, as it is no longer a
differentiator.

Link: https://lore.kernel.org/linux-trace-kernel/20240611031737.982047614@goodmis.org

Cc: Masami Hiramatsu 
Cc: Mark Rutland 
Cc: Mathieu Desnoyers 
Cc: Jonathan Corbet 
Cc: Catalin Marinas 
Cc: Will Deacon 
Cc: Guo Ren 
Cc: Huacai Chen 
Cc: WANG Xuerui 
Cc: Michael Ellerman 
Cc: Nicholas Piggin 
Cc: Christophe Leroy 
Cc: "Naveen N. Rao" 
Cc: Paul Walmsley 
Cc: Palmer Dabbelt 
Cc: Albert Ou 
Cc: Heiko Carstens 
Cc: Vasily Gorbik 
Cc: Alexander Gordeev 
Cc: Christian Borntraeger 
Cc: Sven Schnelle 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: "H. Peter Anvin" 
Signed-off-by: Steven Rostedt (Google)

Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-05-19T16:21:03+00:00

Pull mm updates from Andrew Morton:
"The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.
Notable series include:

- Lucas Stach has provided some page-mapping cleanup/consolidation/
maintainability work in the series "mm/treewide: Remove pXd_huge()
API".

- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
one test.

- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being
allocated: number of calls and amount of memory.

- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in
largely similar code sites.

- In his series "mm: page_alloc: freelist migratetype hygiene"
Johannes Weiner has fixed the page allocator's handling of
migratetype requests, with resulting improvements in compaction
efficiency.

- In the series "make the hugetlb migration strategy consistent"
Baolin Wang has fixed a hugetlb migration issue, which should
improve hugetlb allocation reliability.

- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when
memory almost met memcg limit".

- In the series "mm/filemap: optimize folio adding and splitting"
Kairui Song has optimized pagecache insertion, yielding ~10%
performance improvement in one test.

- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".

- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".

- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".

- More cleanups from Matthew Wilcox in the series "Various
page->flags cleanups".

- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".

- More folio conversions and cleanups in Matthew Wilcox's series:
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"

- David Hildenbrand chipped in with "fs/proc/task_mmu: convert
hugetlb functions to work on folis".

- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".

- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".

- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
series "mm/ksm: fix ksm exec support for prctl".

- Baolin Wang has implemented NUMA balancing for multi-size THPs.
This is a simple first-cut implementation for now. The series is
"support multi-size THP numa balancing".

- Cleanups to vma handling helper functions from Matthew Wilcox in
the series "Unify vma_address and vma_pgoff_address".

- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".

- Improvements to the swapping of multi-size THPs from Ryan Roberts
in the series "Swap-out mTHP without splitting".

- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"

- GUP cleanups from David Hildenbrand in "mm/gup: consistently call
it GUP-fast".

- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
path to use struct vm_fault".

- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".

- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes".
Fixes the initialization code so that migration between different
memory types works as intended.

- David Hildenbrand has improved follow_pte() and fixed an errant
driver in the series "mm: follow_pte() improvements and acrn
follow_pte() fixes".

- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".

- Folio conversions in KSM in Alex Shi's series "transfer page to
folio in KSM".

- Barry Song has added some sysfs stats for monitoring multi-size
THP's in the series "mm: add per-order mTHP alloc and swpout
counters".

- Some zswap cleanups from Yosry Ahmed in the series "zswap
same-filled and limit checking cleanups".

- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".

- Multi-size THPs get more work, this time from Lance Yang. His
series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
optimizes the freeing of these things.

- Kemeng Shi has added more userspace-visible writeback
instrumentation in the series "Improve visibility of writeback".

- Kemeng Shi then sent some maintenance work on top in the series
"Fix and cleanups to page-writeback".

- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
the series "Improve anon_vma scalability for anon VMAs". Intel's
test bot reported an improbable 3x improvement in one test.

- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"

- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"

- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as
XFAIL".

- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".

- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking""

* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
selftests: cgroup: add tests to verify the zswap writeback path
mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
mm/damon/core: fix return value from damos_wmark_metric_value
mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
selftests: cgroup: remove redundant enabling of memory controller
Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
Docs/mm/damon/design: use a list for supported filters
Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
selftests/damon: classify tests for functionalities and regressions
selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
selftests/damon: add a test for DAMOS quota goal
...