linux-toradex.git/arch/arm/lib, branch v5.11

ARM: 9022/1: Change arch/arm/lib/mem*.S to use WEAK instead of .weak

2020-11-12T14:53:19+00:00

Commit d6d51a96c7d6 ("ARM: 9014/2: Replace string mem* functions for
KASan") add .weak directives to memcpy/memmove/memset to avoid collision
with KASAN interceptors.

This does not work with LLVM's integrated assembler (the assembly snippet
`.weak memcpy ... .globl memcpy` produces a STB_GLOBAL memcpy while GNU as
produces a STB_WEAK memcpy). LLVM 12 (since https://reviews.llvm.org/D90108)
will error on such an overridden symbol binding.

Use the appropriate WEAK macro instead.

Link: https://github.com/ClangBuiltLinux/linux/issues/1190
--

Fixes: d6d51a96c7d6 ("ARM: 9014/2: Replace string mem* functions for KASan")
Reported-by: Nick Desaulniers 
Signed-off-by: Fangrui Song 
Reviewed-by: Nick Desaulniers 
Tested-by: Nick Desaulniers 
Signed-off-by: Russell King

ARM: 9014/2: Replace string mem* functions for KASan

2020-10-27T12:11:06+00:00

Functions like memset()/memmove()/memcpy() do a lot of memory
accesses.

If a bad pointer is passed to one of these functions it is important
to catch this. Compiler instrumentation cannot do this since these
functions are written in assembly.

KASan replaces these memory functions with instrumented variants.

The original functions are declared as weak symbols so that
the strong definitions in mm/kasan/kasan.c can replace them.

The original functions have aliases with a '__' prefix in their
name, so we can call the non-instrumented variant if needed.

We must use __memcpy()/__memset() in place of memcpy()/memset()
when we copy .data to RAM and when we clear .bss, because
kasan_early_init cannot be called before the initialization of
.data and .bss.

For the kernel compression and EFI libstub's custom string
libraries we need a special quirk: even if these are built
without KASan enabled, they rely on the global headers for their
custom string libraries, which means that e.g. memcpy()
will be defined to __memcpy() and we get link failures.
Since these implementations are written i C rather than
assembly we use e.g. __alias(memcpy) to redirected any
users back to the local implementation.

Cc: Andrey Ryabinin 
Cc: Alexander Potapenko 
Cc: Dmitry Vyukov 
Cc: kasan-dev@googlegroups.com
Reviewed-by: Ard Biesheuvel 
Tested-by: Ard Biesheuvel  # QEMU/KVM/mach-virt/LPAE/8G
Tested-by: Florian Fainelli  # Brahma SoCs
Tested-by: Ahmad Fatoum  # i.MX6Q
Reported-by: Russell King - ARM Linux 
Signed-off-by: Ahmad Fatoum 
Signed-off-by: Abbott Liu 
Signed-off-by: Florian Fainelli 
Signed-off-by: Linus Walleij 
Signed-off-by: Russell King

arm: propagate the calling convention changes down to csum_partial_copy_from_user()

2020-08-20T19:45:16+00:00

... and get rid of the "clean the destination on error" crap.
Simplifies the fault handlers and the function itself...

Signed-off-by: Al Viro

csum_partial_copy_nocheck(): drop the last argument

2020-08-20T19:45:14+00:00

It's always 0.  Note that we theoretically could use ~0U as well -
result will be the same modulo 0xffff, _if_ the damn thing did the
right thing for any value of initial sum; later we'll make use of
that when convenient.

However, unlike csum_and_copy_..._user(), there are instances that
did not work for arbitrary initial sums; c6x is one such.

Signed-off-by: Al Viro

mmap locking API: use coccinelle to convert mmap_sem rwsem call sites

2020-06-09T16:39:14+00:00

This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

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

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

Signed-off-by: Michel Lespinasse 
Signed-off-by: Andrew Morton 
Reviewed-by: Daniel Jordan 
Reviewed-by: Laurent Dufour 
Reviewed-by: Vlastimil Babka 
Cc: Davidlohr Bueso 
Cc: David Rientjes 
Cc: Hugh Dickins 
Cc: Jason Gunthorpe 
Cc: Jerome Glisse 
Cc: John Hubbard 
Cc: Liam Howlett 
Cc: Matthew Wilcox 
Cc: Peter Zijlstra 
Cc: Ying Han 
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds

arm/asm: add loglvl to c_backtrace()

2020-06-09T16:39:10+00:00

Currently, the log-level of show_stack() depends on a platform
realization.  It creates situations where the headers are printed with
lower log level or higher than the stacktrace (depending on a platform or
user).

Furthermore, it forces the logic decision from user to an architecture
side.  In result, some users as sysrq/kdb/etc are doing tricks with
temporary rising console_loglevel while printing their messages.  And in
result it not only may print unwanted messages from other CPUs, but also
omit printing at all in the unlucky case where the printk() was deferred.

Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier
approach than introducing more printk buffers.  Also, it will consolidate
printings with headers.

Add log level argument to c_backtrace() as a preparation for introducing
show_stack_loglvl().

[1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u

Signed-off-by: Dmitry Safonov 
Signed-off-by: Andrew Morton 
Cc: Russell King 
Cc: Will Deacon 
Link: http://lkml.kernel.org/r/20200418201944.482088-5-dima@arista.com
Signed-off-by: Linus Torvalds

arm: add support for folded p4d page tables

2020-06-05T02:06:21+00:00

Implement primitives necessary for the 4th level folding, add walks of p4d
level where appropriate, and remove __ARCH_USE_5LEVEL_HACK.

[rppt@linux.ibm.com: fix kexec]
  Link: http://lkml.kernel.org/r/20200508174232.GA759899@linux.ibm.com
Signed-off-by: Mike Rapoport 
Signed-off-by: Andrew Morton 
Tested-by: Marek Szyprowski 
Cc: Arnd Bergmann 
Cc: Benjamin Herrenschmidt 
Cc: Brian Cain 
Cc: Catalin Marinas 
Cc: Christophe Leroy 
Cc: Fenghua Yu 
Cc: Geert Uytterhoeven 
Cc: Guan Xuetao 
Cc: James Morse 
Cc: Jonas Bonn 
Cc: Julien Thierry 
Cc: Ley Foon Tan 
Cc: Marc Zyngier 
Cc: Michael Ellerman 
Cc: Paul Mackerras 
Cc: Rich Felker 
Cc: Russell King 
Cc: Stafford Horne 
Cc: Stefan Kristiansson 
Cc: Suzuki K Poulose 
Cc: Tony Luck 
Cc: Will Deacon 
Cc: Yoshinori Sato 
Link: http://lkml.kernel.org/r/20200414153455.21744-3-rppt@kernel.org
Signed-off-by: Linus Torvalds

ARM: 8958/1: rename missed uaccess .fixup section

2020-02-21T17:03:21+00:00

When the uaccess .fixup section was renamed to .text.fixup, one case was
missed. Under ld.bfd, the orphaned section was moved close to .text
(since they share the "ax" bits), so things would work normally on
uaccess faults. Under ld.lld, the orphaned section was placed outside
the .text section, making it unreachable.

Link: https://github.com/ClangBuiltLinux/linux/issues/282
Link: https://bugs.chromium.org/p/chromium/issues/detail?id=1020633#c44
Link: https://lore.kernel.org/r/nycvar.YSQ.7.76.1912032147340.17114@knanqh.ubzr
Link: https://lore.kernel.org/lkml/202002071754.F5F073F1D@keescook/

Fixes: c4a84ae39b4a5 ("ARM: 8322/1: keep .text and .fixup regions closer together")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook 
Reviewed-by: Ard Biesheuvel 
Reviewed-by: Nick Desaulniers 
Signed-off-by: Russell King

Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm

2019-09-22T16:39:09+00:00

Pull ARM updates from Russell King:

 - fix various clang build and cppcheck issues

 - switch ARM to use new common outgoing-CPU-notification code

 - add some additional explanation about the boot code

 - kbuild "make clean" fixes

 - get rid of another "(____ptrval____)", this time for the VDSO code

 - avoid treating cache maintenance faults as a write

 - add a frame pointer unwinder implementation for clang

 - add EDAC support for Aurora L2 cache

 - improve robustness of adjust_lowmem_bounds() finding the bounds of
   lowmem.

 - add reset control for AMBA primecell devices

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (24 commits)
  ARM: 8906/1: drivers/amba: add reset control to amba bus probe
  ARM: 8905/1: Emit __gnu_mcount_nc when using Clang 10.0.0 or newer
  ARM: 8904/1: skip nomap memblocks while finding the lowmem/highmem boundary
  ARM: 8903/1: ensure that usable memory in bank 0 starts from a PMD-aligned address
  ARM: 8891/1: EDAC: armada_xp: Add support for more SoCs
  ARM: 8888/1: EDAC: Add driver for the Marvell Armada XP SDRAM and L2 cache ECC
  ARM: 8892/1: EDAC: Add missing debugfs_create_x32 wrapper
  ARM: 8890/1: l2x0: add marvell,ecc-enable property for aurora
  ARM: 8889/1: dt-bindings: document marvell,ecc-enable binding
  ARM: 8886/1: l2x0: support parity-enable/disable on aurora
  ARM: 8885/1: aurora-l2: add defines for parity and ECC registers
  ARM: 8887/1: aurora-l2: add prefix to MAX_RANGE_SIZE
  ARM: 8902/1: l2c: move cache-aurora-l2.h to asm/hardware
  ARM: 8900/1: UNWINDER_FRAME_POINTER implementation for Clang
  ARM: 8898/1: mm: Don't treat faults reported from cache maintenance as writes
  ARM: 8896/1: VDSO: Don't leak kernel addresses
  ARM: 8895/1: visit mach-* and plat-* directories when cleaning
  ARM: 8894/1: boot: Replace open-coded nop with macro
  ARM: 8893/1: boot: Explain the 8 nops
  ARM: 8876/1: fix O= building with CONFIG_FPE_FASTFPE
  ...

ARM: 8900/1: UNWINDER_FRAME_POINTER implementation for Clang

2019-08-29T06:58:01+00:00

The stackframe setup when compiled with clang is different.
Since the stack unwinder expects the gcc stackframe setup it
fails to print backtraces. This patch adds support for the
clang stackframe setup.

Link: https://github.com/ClangBuiltLinux/linux/issues/35

Cc: clang-built-linux@googlegroups.com
Suggested-by: Tri Vo 
Signed-off-by: Nathan Huckleberry 
Tested-by: Nick Desaulniers 
Reviewed-by: Nick Desaulniers 
Signed-off-by: Russell King