linux-toradex.git/lib, branch v5.12-rc3

kasan: fix KASAN_STACK dependency for HW_TAGS

2021-03-13T19:27:31+00:00

There's a runtime failure when running HW_TAGS-enabled kernel built with
GCC on hardware that doesn't support MTE.  GCC-built kernels always have
CONFIG_KASAN_STACK enabled, even though stack instrumentation isn't
supported by HW_TAGS.  Having that config enabled causes KASAN to issue
MTE-only instructions to unpoison kernel stacks, which causes the failure.

Fix the issue by disallowing CONFIG_KASAN_STACK when HW_TAGS is used.

(The commit that introduced CONFIG_KASAN_HW_TAGS specified proper
 dependency for CONFIG_KASAN_STACK_ENABLE but not for CONFIG_KASAN_STACK.)

Link: https://lkml.kernel.org/r/59e75426241dbb5611277758c8d4d6f5f9298dac.1615215441.git.andreyknvl@google.com
Fixes: 6a63a63ff1ac ("kasan: introduce CONFIG_KASAN_HW_TAGS")
Signed-off-by: Andrey Konovalov 
Reported-by: Catalin Marinas 
Cc: 
Cc: Will Deacon 
Cc: Vincenzo Frascino 
Cc: Dmitry Vyukov 
Cc: Andrey Ryabinin 
Cc: Alexander Potapenko 
Cc: Marco Elver 
Cc: Peter Collingbourne 
Cc: Evgenii Stepanov 
Cc: Branislav Rankov 
Cc: Kevin Brodsky 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge git://git.kernel.org:/pub/scm/linux/kernel/git/davem/sparc

2021-03-09T06:01:58+00:00

Pull sparc updates from David Miller:
 "Just some more random bits from Al, including a conversion over to
  generic extables"

* git://git.kernel.org:/pub/scm/linux/kernel/git/davem/sparc:
  sparc32: take ->thread.flags out
  sparc32: get rid of fake_swapper_regs
  sparc64: get rid of fake_swapper_regs
  sparc32: switch to generic extables
  sparc32: switch copy_user.S away from range exception table entries
  sparc32: get rid of range exception table entries in checksum_32.S
  sparc32: switch __bzero() away from range exception table entries
  sparc32: kill lookup_fault()
  sparc32: don't bother with lookup_fault() in __bzero()

Merge branch 'kmap-conversion-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

2021-03-01T19:24:18+00:00

Pull kmap conversion updates from David Sterba:
 "This contains changes regarding kmap API use and eg conversion from
  kmap_atomic to kmap_local_page.

  The API belongs to memory management but to save cross-tree
  dependency headaches we've agreed to take it through the btrfs tree
  because there are some trivial conversions possible, while the rest
  will need some time and getting the easy cases out of the way would be
  convenient.

  The changes can be grouped:

   - function exports, new helpers

   - new VM_BUG_ON for additional verification; it's been discussed if
     it should be VM_BUG_ON or BUG_ON, the former was chosen due to
     performance reasons

   - code replaced by relevant helpers"

[ This is an updated version of a request that originally came in during
  the merge window, but I asked for some updates:

    https://lore.kernel.org/lkml/cover.1614090658.git.dsterba@suse.com/

  which is why this got merge after the merge window closed.  - Linus ]

* 'kmap-conversion-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: use copy_highpage() instead of 2 kmaps()
  btrfs: use memcpy_[to|from]_page() and kmap_local_page()
  mm/highmem: Add VM_BUG_ON() to mem*_page() calls
  mm/highmem: Introduce memcpy_page(), memmove_page(), and memset_page()
  mm/highmem: Convert memcpy_[to|from]_page() to kmap_local_page()
  mm/highmem: Lift memcpy_[to|from]_page to core

Merge branch 'work.sparc32' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2021-02-27T00:16:24+00:00

ubsan: remove overflow checks

2021-02-26T17:41:05+00:00

Since GCC 8.0 -fsanitize=signed-integer-overflow doesn't work with
-fwrapv.  -fwrapv makes signed overflows defines and GCC essentially
disables ubsan checks.  On GCC < 8.0 -fwrapv doesn't have influence on
-fsanitize=signed-integer-overflow setting, so it kinda works but
generates false-positves and violates uaccess rules:

lib/iov_iter.o: warning: objtool: iovec_from_user()+0x22d: call to
__ubsan_handle_add_overflow() with UACCESS enabled

Disable signed overflow checks to avoid these problems.  Remove unsigned
overflow checks as well.  Unsigned overflow appeared as side effect of
commit cdf8a76fda4a ("ubsan: move cc-option tests into Kconfig"), but it
never worked (kernel doesn't boot).  And unsigned overflows are allowed by
C standard, so it just pointless.

Link: https://lkml.kernel.org/r/20210209232348.20510-1-ryabinin.a.a@gmail.com
Signed-off-by: Andrey Ryabinin 
Acked-by: Peter Zijlstra (Intel) 
Cc: Josh Poimboeuf 
Cc: Randy Dunlap 
Cc: Stephen Rothwell 
Cc: Dmitry Vyukov 
Cc: Kees Cook 
Cc: Alexander Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/cmdline: remove an unneeded local variable in next_arg()

2021-02-26T17:41:04+00:00

The local variable 'next' is unneeded because you can simply advance the
existing pointer 'args'.

Link: https://lkml.kernel.org/r/20210201014707.3828753-1-masahiroy@kernel.org
Signed-off-by: Masahiro Yamada 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: stackdepot: fix ignoring return value warning

2021-02-26T17:41:04+00:00

Fix the below ignoring return value warning for kstrtobool in
is_stack_depot_disabled function.

lib/stackdepot.c: In function 'is_stack_depot_disabled':
lib/stackdepot.c:154:2: warning: ignoring return value of 'kstrtobool'
declared with attribute 'warn_unused_result' [-Wunused-result]

Link: https://lkml.kernel.org/r/1612163048-28026-1-git-send-email-vjitta@codeaurora.org
Fixes: b9779abb09a8 ("lib: stackdepot: add support to disable stack depot")
Signed-off-by: Vijayanand Jitta 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: stackdepot: add support to disable stack depot

2021-02-26T17:41:04+00:00

Add a kernel parameter stack_depot_disable to disable stack depot.  So
that stack hash table doesn't consume any memory when stack depot is
disabled.

The use case is CONFIG_PAGE_OWNER without page_owner=on.  Without this
patch, stackdepot will consume the memory for the hashtable.  By default,
it's 8M which is never trivial.

With this option, in CONFIG_PAGE_OWNER configured system, page_owner=off,
stack_depot_disable in kernel command line, we could save the wasted
memory for the hashtable.

[akpm@linux-foundation.org: fix CONFIG_STACKDEPOT=n build]

Link: https://lkml.kernel.org/r/1611749198-24316-2-git-send-email-vjitta@codeaurora.org
Signed-off-by: Vinayak Menon 
Signed-off-by: Vijayanand Jitta 
Cc: Alexander Potapenko 
Cc: Minchan Kim 
Cc: Yogesh Lal 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: stackdepot: add support to configure STACK_HASH_SIZE

2021-02-26T17:41:04+00:00

Use CONFIG_STACK_HASH_ORDER to configure STACK_HASH_SIZE.

Aim is to have configurable value for  STACK_HASH_SIZE,
so depend on use case one can configure it.

One example is of Page Owner, CONFIG_PAGE_OWNER works only if
page_owner=on via kernel parameter on CONFIG_PAGE_OWNER configured system.
Thus, unless admin enable it via command line option, the stackdepot will
just waste 8M memory without any customer.

Making it configurable and use lower value helps to enable features like
CONFIG_PAGE_OWNER without any significant overhead.

Link: https://lkml.kernel.org/r/1611749198-24316-1-git-send-email-vjitta@codeaurora.org
Signed-off-by: Yogesh Lal 
Signed-off-by: Vinayak Menon 
Signed-off-by: Vijayanand Jitta 
Reviewed-by: Minchan Kim 
Reviewed-by: Alexander Potapenko 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib/genalloc.c: change return type to unsigned long for bitmap_set_ll

2021-02-26T17:41:04+00:00

Just as bitmap_clear_ll(), change return type to unsigned long
for bitmap_set_ll to avoid the possible overflow in future.

Link: https://lkml.kernel.org/r/20210105031644.2771-1-sjhuang@iluvatar.ai
Signed-off-by: Huang Shijie 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds