linux-stable.git/arch/arm/include, branch v5.7.2

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

2020-05-26T00:11:39+00:00

Pull ARM fixes from Russell King:

 - correct value of decompressor tag size in header

 - fix DACR value when we have nested exceptions

 - fix a missing newline on a kernel message

 - fix mask for ptrace thumb breakpoint hook

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: 8977/1: ptrace: Fix mask for thumb breakpoint hook
  ARM: 8973/1: Add missing newline terminator to kernel message
  ARM: uaccess: fix DACR mismatch with nested exceptions
  ARM: uaccess: integrate uaccess_save and uaccess_restore
  ARM: uaccess: consolidate uaccess asm to asm/uaccess-asm.h
  ARM: 8970/1: decompressor: increase tag size

Merge branch 'uaccess' into fixes

2020-05-07T19:53:53+00:00

ARM: futex: Address build warning

2020-05-06T22:41:47+00:00

Stephen reported the following build warning on a ARM multi_v7_defconfig
build with GCC 9.2.1:

kernel/futex.c: In function 'do_futex':
kernel/futex.c:1676:17: warning: 'oldval' may be used uninitialized in this function [-Wmaybe-uninitialized]
 1676 |   return oldval == cmparg;
      |          ~~~~~~~^~~~~~~~~
kernel/futex.c:1652:6: note: 'oldval' was declared here
 1652 |  int oldval, ret;
      |      ^~~~~~

introduced by commit a08971e9488d ("futex: arch_futex_atomic_op_inuser()
calling conventions change").

While that change should not make any difference it confuses GCC which
fails to work out that oldval is not referenced when the return value is
not zero.

GCC fails to properly analyze arch_futex_atomic_op_inuser(). It's not the
early return, the issue is with the assembly macros. GCC fails to detect
that those either set 'ret' to 0 and set oldval or set 'ret' to -EFAULT
which makes oldval uninteresting. The store to the callsite supplied oldval
pointer is conditional on ret == 0.

The straight forward way to solve this is to make the store unconditional.

Aside of addressing the build warning this makes sense anyway because it
removes the conditional from the fastpath. In the error case the stored
value is uninteresting and the extra store does not matter at all.

Reported-by: Stephen Rothwell 
Signed-off-by: Thomas Gleixner 
Link: https://lkml.kernel.org/r/87pncao2ph.fsf@nanos.tec.linutronix.de

ARM: uaccess: fix DACR mismatch with nested exceptions

2020-05-03T16:30:27+00:00

Tomas Paukrt reports that his SAM9X60 based system (ARM926, ARMv5TJ)
fails to fix up alignment faults, eventually resulting in a kernel
oops.

The problem occurs when using CONFIG_CPU_USE_DOMAINS with commit
e6978e4bf181 ("ARM: save and reset the address limit when entering an
exception").  This is because the address limit is set back to
TASK_SIZE on exception entry, and, although it is restored on exception
exit, the domain register is not.

Hence, this sequence can occur:

  interrupt
    pt_regs->addr_limit = addr_limit		// USER_DS
    addr_limit = USER_DS
    alignment exception
    __probe_kernel_read()
      old_fs = get_fs()				// USER_DS
      set_fs(KERNEL_DS)
        addr_limit = KERNEL_DS
        dacr.kernel = DOMAIN_MANAGER
        interrupt
          pt_regs->addr_limit = addr_limit	// KERNEL_DS
          addr_limit = USER_DS
          alignment exception
          __probe_kernel_read()
            old_fs = get_fs()			// USER_DS
            set_fs(KERNEL_DS)
              addr_limit = KERNEL_DS
              dacr.kernel = DOMAIN_MANAGER
            ...
            set_fs(old_fs)
              addr_limit = USER_DS
              dacr.kernel = DOMAIN_CLIENT
          ...
          addr_limit = pt_regs->addr_limit	// KERNEL_DS
        interrupt returns

At this point, addr_limit is correctly restored to KERNEL_DS for
__probe_kernel_read() to continue execution, but dacr.kernel is not,
it has been reset by the set_fs(old_fs) to DOMAIN_CLIENT.

This would not have happened prior to the mentioned commit, because
addr_limit would remain KERNEL_DS, so get_fs() would have returned
KERNEL_DS, and so would correctly nest.

This commit fixes the problem by also saving the DACR on exception
entry if either CONFIG_CPU_SW_DOMAIN_PAN or CONFIG_CPU_USE_DOMAINS are
enabled, and resetting the DACR appropriately on exception entry to
match addr_limit and PAN settings.

Fixes: e6978e4bf181 ("ARM: save and reset the address limit when entering an exception")
Reported-by: Tomas Paukrt 
Signed-off-by: Russell King

ARM: uaccess: integrate uaccess_save and uaccess_restore

2020-05-03T16:30:26+00:00

Integrate uaccess_save / uaccess_restore macros into the new
uaccess_entry / uaccess_exit macros respectively.

Signed-off-by: Russell King

ARM: uaccess: consolidate uaccess asm to asm/uaccess-asm.h

2020-05-03T16:30:24+00:00

Consolidate the user access assembly code to asm/uaccess-asm.h.  This
moves the csdb, check_uaccess, uaccess_mask_range_ptr, uaccess_enable,
uaccess_disable, uaccess_save, uaccess_restore macros, and creates two
new ones for exception entry and exit - uaccess_entry and uaccess_exit.

This makes the uaccess_save and uaccess_restore macros private to
asm/uaccess-asm.h.

Signed-off-by: Russell King

arch: split MODULE_ARCH_VERMAGIC definitions out to

2020-04-23T01:50:26+00:00

As the bug report [1] pointed out,  must be included
after .

I believe we should not impose any include order restriction. We often
sort include directives alphabetically, but it is just coding style
convention. Technically, we can include header files in any order by
making every header self-contained.

Currently, arch-specific MODULE_ARCH_VERMAGIC is defined in
, which is not included from .

Hence, the straight-forward fix-up would be as follows:

|--- a/include/linux/vermagic.h
|+++ b/include/linux/vermagic.h
|@@ -1,5 +1,6 @@
| /* SPDX-License-Identifier: GPL-2.0 */
| #include 
|+#include 
|
| /* Simply sanity version stamp for modules. */
| #ifdef CONFIG_SMP

This works enough, but for further cleanups, I split MODULE_ARCH_VERMAGIC
definitions into .

With this,  and  will be orthogonal,
and the location of MODULE_ARCH_VERMAGIC definitions will be consistent.

For arc and ia64, MODULE_PROC_FAMILY is only used for defining
MODULE_ARCH_VERMAGIC. I squashed it.

For hexagon, nds32, and xtensa, I removed  entirely
because they contained nothing but MODULE_ARCH_VERMAGIC definition.
Kbuild will automatically generate  at build-time,
wrapping .

[1] https://lore.kernel.org/lkml/20200411155623.GA22175@zn.tnic

Reported-by: Borislav Petkov 
Signed-off-by: Masahiro Yamada 
Acked-by: Jessica Yu

mm/special: create generic fallbacks for pte_special() and pte_mkspecial()

2020-04-10T22:36:21+00:00

Currently there are many platforms that dont enable ARCH_HAS_PTE_SPECIAL
but required to define quite similar fallback stubs for special page
table entry helpers such as pte_special() and pte_mkspecial(), as they
get build in generic MM without a config check.  This creates two
generic fallback stub definitions for these helpers, eliminating much
code duplication.

mips platform has a special case where pte_special() and pte_mkspecial()
visibility is wider than what ARCH_HAS_PTE_SPECIAL enablement requires.
This restricts those symbol visibility in order to avoid redefinitions
which is now exposed through this new generic stubs and subsequent build
failure.  arm platform set_pte_at() definition needs to be moved into a
C file just to prevent a build failure.

[anshuman.khandual@arm.com: use defined(CONFIG_ARCH_HAS_PTE_SPECIAL) in mips per Thomas]
  Link: http://lkml.kernel.org/r/1583851924-21603-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual 
Signed-off-by: Andrew Morton 
Acked-by: Guo Ren 			[csky]
Acked-by: Geert Uytterhoeven 	[m68k]
Acked-by: Stafford Horne 		[openrisc]
Acked-by: Helge Deller 			[parisc]
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: Russell King 
Cc: Brian Cain 
Cc: Tony Luck 
Cc: Fenghua Yu 
Cc: Sam Creasey 
Cc: Michal Simek 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: Nick Hu 
Cc: Greentime Hu 
Cc: Vincent Chen 
Cc: Ley Foon Tan 
Cc: Jonas Bonn 
Cc: Stefan Kristiansson 
Cc: "James E.J. Bottomley" 
Cc: "David S. Miller" 
Cc: Jeff Dike 
Cc: Richard Weinberger 
Cc: Anton Ivanov 
Cc: Guan Xuetao 
Cc: Chris Zankel 
Cc: Max Filippov 
Cc: Thomas Bogendoerfer 
Link: http://lkml.kernel.org/r/1583802551-15406-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds

mm/vma: define a default value for VM_DATA_DEFAULT_FLAGS

2020-04-10T22:36:21+00:00

There are many platforms with exact same value for VM_DATA_DEFAULT_FLAGS
This creates a default value for VM_DATA_DEFAULT_FLAGS in line with the
existing VM_STACK_DEFAULT_FLAGS.  While here, also define some more
macros with standard VMA access flag combinations that are used
frequently across many platforms.  Apart from simplification, this
reduces code duplication as well.

Signed-off-by: Anshuman Khandual 
Signed-off-by: Andrew Morton 
Reviewed-by: Vlastimil Babka 
Acked-by: Geert Uytterhoeven 
Cc: Richard Henderson 
Cc: Vineet Gupta 
Cc: Russell King 
Cc: Catalin Marinas 
Cc: Mark Salter 
Cc: Guo Ren 
Cc: Yoshinori Sato 
Cc: Brian Cain 
Cc: Tony Luck 
Cc: Michal Simek 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: Nick Hu 
Cc: Ley Foon Tan 
Cc: Jonas Bonn 
Cc: "James E.J. Bottomley" 
Cc: Michael Ellerman 
Cc: Paul Walmsley 
Cc: Heiko Carstens 
Cc: Rich Felker 
Cc: "David S. Miller" 
Cc: Guan Xuetao 
Cc: Thomas Gleixner 
Cc: Jeff Dike 
Cc: Chris Zankel 
Link: http://lkml.kernel.org/r/1583391014-8170-2-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Linus Torvalds

Merge tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping

2020-04-04T17:12:47+00:00

Pull dma-mapping updates from Christoph Hellwig:

 - fix an integer overflow in the coherent pool (Kevin Grandemange)

 - provide support for in-place uncached remapping and use that for
   openrisc

 - fix the arm coherent allocator to take the bus limit into account

* tag 'dma-mapping-5.7' of git://git.infradead.org/users/hch/dma-mapping:
  ARM/dma-mapping: merge __dma_supported into arm_dma_supported
  ARM/dma-mapping: take the bus limit into account in __dma_alloc
  ARM/dma-mapping: remove get_coherent_dma_mask
  openrisc: use the generic in-place uncached DMA allocator
  dma-direct: provide a arch_dma_clear_uncached hook
  dma-direct: make uncached_kernel_address more general
  dma-direct: consolidate the error handling in dma_direct_alloc_pages
  dma-direct: remove the cached_kernel_address hook
  dma-coherent: fix integer overflow in the reserved-memory dma allocation