linux-stable.git/arch/arm, branch v4.4.233

ARM: 8992/1: Fix unwind_frame for clang-built kernels

2020-08-21T08:53:04+00:00

commit b4d5ec9b39f8b31d98f65bc5577b5d15d93795d7 upstream.

Since clang does not push pc and sp in function prologues, the current
implementation of unwind_frame does not work. By using the previous
frame's lr/fp instead of saved pc/sp we get valid unwinds on clang-built
kernels.

The bounds check on next frame pointer must be changed as well since
there are 8 less bytes between frames.

This fixes /proc//stack.

Link: https://github.com/ClangBuiltLinux/linux/issues/912

Reported-by: Miles Chen 
Tested-by: Miles Chen 
Cc: stable@vger.kernel.org
Reviewed-by: Nick Desaulniers 
Signed-off-by: Nathan Huckleberry 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman

ARM: socfpga: PM: add missing put_device() call in socfpga_setup_ocram_self_refresh()

2020-08-21T08:52:58+00:00

[ Upstream commit 3ad7b4e8f89d6bcc9887ca701cf2745a6aedb1a0 ]

if of_find_device_by_node() succeed, socfpga_setup_ocram_self_refresh
doesn't have a corresponding put_device(). Thus add a jump target to
fix the exception handling for this function implementation.

Fixes: 44fd8c7d4005 ("ARM: socfpga: support suspend to ram")
Signed-off-by: Yu Kuai 
Signed-off-by: Dinh Nguyen 
Signed-off-by: Sasha Levin

ARM: at91: pm: add missing put_device() call in at91_pm_sram_init()

2020-08-21T08:52:58+00:00

[ Upstream commit f87a4f022c44e5b87e842a9f3e644fba87e8385f ]

if of_find_device_by_node() succeed, at91_pm_sram_init() doesn't have
a corresponding put_device(). Thus add a jump target to fix the exception
handling for this function implementation.

Fixes: d2e467905596 ("ARM: at91: pm: use the mmio-sram pool to access SRAM")
Signed-off-by: yu kuai 
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20200604123301.3905837-1-yukuai3@huawei.com
Signed-off-by: Sasha Levin

ARM: percpu.h: fix build error

2020-08-21T08:52:54+00:00

commit aa54ea903abb02303bf55855fb51e3fcee135d70 upstream.

Fix build error for the case:
  defined(CONFIG_SMP) && !defined(CONFIG_CPU_V6)

config: keystone_defconfig

  CC      arch/arm/kernel/signal.o
  In file included from ../include/linux/random.h:14,
                    from ../arch/arm/kernel/signal.c:8:
  ../arch/arm/include/asm/percpu.h: In function ‘__my_cpu_offset’:
  ../arch/arm/include/asm/percpu.h:29:34: error: ‘current_stack_pointer’ undeclared (first use in this function); did you mean ‘user_stack_pointer’?
      : "Q" (*(const unsigned long *)current_stack_pointer));
                                     ^~~~~~~~~~~~~~~~~~~~~
                                     user_stack_pointer

Fixes: f227e3ec3b5c ("random32: update the net random state on interrupt and activity")
Signed-off-by: Grygorii Strashko 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

ARM: 8986/1: hw_breakpoint: Don't invoke overflow handler on uaccess watchpoints

2020-08-21T08:52:53+00:00

[ Upstream commit eec13b42d41b0f3339dcf0c4da43734427c68620 ]

Unprivileged memory accesses generated by the so-called "translated"
instructions (e.g. LDRT) in kernel mode can cause user watchpoints to fire
unexpectedly. In such cases, the hw_breakpoint logic will invoke the user
overflow handler which will typically raise a SIGTRAP back to the current
task. This is futile when returning back to the kernel because (a) the
signal won't have been delivered and (b) userspace can't handle the thing
anyway.

Avoid invoking the user overflow handler for watchpoints triggered by
kernel uaccess routines, and instead single-step over the faulting
instruction as we would if no overflow handler had been installed.

Cc: 
Fixes: f81ef4a920c8 ("ARM: 6356/1: hw-breakpoint: add ARM backend for the hw-breakpoint framework")
Reported-by: Luis Machado 
Tested-by: Luis Machado 
Signed-off-by: Will Deacon 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

ARM: imx5: add missing put_device() call in imx_suspend_alloc_ocram()

2020-06-30T00:08:01+00:00

[ Upstream commit 586745f1598ccf71b0a5a6df2222dee0a865954e ]

if of_find_device_by_node() succeed, imx_suspend_alloc_ocram() doesn't
have a corresponding put_device(). Thus add a jump target to fix the
exception handling for this function implementation.

Fixes: 1579c7b9fe01 ("ARM: imx53: Set DDR pins to high impedance when in suspend to RAM.")
Signed-off-by: yu kuai 
Signed-off-by: Shawn Guo 
Signed-off-by: Sasha Levin

ARM: tegra: Correct PL310 Auxiliary Control Register initialization

2020-06-20T08:23:24+00:00

commit 35509737c8f958944e059d501255a0bf18361ba0 upstream.

The PL310 Auxiliary Control Register shouldn't have the "Full line of
zero" optimization bit being set before L2 cache is enabled. The L2X0
driver takes care of enabling the optimization by itself.

This patch fixes a noisy error message on Tegra20 and Tegra30 telling
that cache optimization is erroneously enabled without enabling it for
the CPU:

	L2C-310: enabling full line of zeros but not enabled in Cortex-A9

Cc: 
Signed-off-by: Dmitry Osipenko 
Tested-by: Nicolas Chauvet 
Signed-off-by: Thierry Reding 
Signed-off-by: Greg Kroah-Hartman

ARM: 8978/1: mm: make act_mm() respect THREAD_SIZE

2020-06-20T08:23:20+00:00

[ Upstream commit e1de94380af588bdf6ad6f0cc1f75004c35bc096 ]

Recent work with KASan exposed the folling hard-coded bitmask
in arch/arm/mm/proc-macros.S:

  bic     rd, sp, #8128
  bic     rd, rd, #63

This forms the bitmask 0x1FFF that is coinciding with
(PAGE_SIZE << THREAD_SIZE_ORDER) - 1, this code was assuming
that THREAD_SIZE is always 8K (8192).

As KASan was increasing THREAD_SIZE_ORDER to 2, I ran into
this bug.

Fix it by this little oneline suggested by Ard:

  bic     rd, sp, #(THREAD_SIZE - 1) & ~63

Where THREAD_SIZE is defined using THREAD_SIZE_ORDER.

We have to also include  since the THREAD_SIZE
expands to use the _AC() macro.

Cc: Ard Biesheuvel 
Cc: Florian Fainelli 
Suggested-by: Ard Biesheuvel 
Signed-off-by: Linus Walleij 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

ARM: 8977/1: ptrace: Fix mask for thumb breakpoint hook

2020-06-20T08:23:15+00:00

[ Upstream commit 3866f217aaa81bf7165c7f27362eee5d7919c496 ]

call_undef_hook() in traps.c applies the same instr_mask for both 16-bit
and 32-bit thumb instructions. If instr_mask then is only 16 bits wide
(0xffff as opposed to 0xffffffff), the first half-word of 32-bit thumb
instructions will be masked out. This makes the function match 32-bit
thumb instructions where the second half-word is equal to instr_val,
regardless of the first half-word.

The result in this case is that all undefined 32-bit thumb instructions
with the second half-word equal to 0xde01 (udf #1) work as breakpoints
and will raise a SIGTRAP instead of a SIGILL, instead of just the one
intended 16-bit instruction. An example of such an instruction is
0xeaa0de01, which is unallocated according to Arm ARM and should raise a
SIGILL, but instead raises a SIGTRAP.

This patch fixes the issue by setting all the bits in instr_mask, which
will still match the intended 16-bit thumb instruction (where the
upper half is always 0), but not any 32-bit thumb instructions.

Cc: Oleg Nesterov 
Signed-off-by: Fredrik Strupe 
Signed-off-by: Russell King 
Signed-off-by: Sasha Levin

ARM: futex: Address build warning

2020-05-27T14:40:24+00:00

[ Upstream commit 8101b5a1531f3390b3a69fa7934c70a8fd6566ad ]

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
Signed-off-by: Sasha Levin