linux-stable.git/arch, branch v4.4.99

security/keys: add CONFIG_KEYS_COMPAT to Kconfig

2017-11-18T10:11:07+00:00

commit 47b2c3fff4932e6fc17ce13d51a43c6969714e20 upstream.

CONFIG_KEYS_COMPAT is defined in arch-specific Kconfigs and is missing for
several 64-bit architectures : mips, parisc, tile.

At the moment and for those architectures, calling in 32-bit userspace the
keyctl syscall would return an ENOSYS error.

This patch moves the CONFIG_KEYS_COMPAT option to security/keys/Kconfig, to
make sure the compatibility wrapper is registered by default for any 64-bit
architecture as long as it is configured with CONFIG_COMPAT.

[DH: Modified to remove arm64 compat enablement also as requested by Eric
 Biggers]

Signed-off-by: Bilal Amarni 
Signed-off-by: David Howells 
Reviewed-by: Arnd Bergmann 
cc: Eric Biggers 
Signed-off-by: James Morris 
Cc: James Cowgill 
Signed-off-by: Greg Kroah-Hartman

x86/oprofile/ppro: Do not use __this_cpu*() in preemptible context

2017-11-15T16:13:14+00:00

commit a743bbeef27b9176987ec0cb7f906ab0ab52d1da upstream.

The warning below says it all:

  BUG: using __this_cpu_read() in preemptible [00000000] code: swapper/0/1
  caller is __this_cpu_preempt_check
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.14.0-rc8 #4
  Call Trace:
   dump_stack
   check_preemption_disabled
   ? do_early_param
   __this_cpu_preempt_check
   arch_perfmon_init
   op_nmi_init
   ? alloc_pci_root_info
   oprofile_arch_init
   oprofile_init
   do_one_initcall
   ...

These accessors should not have been used in the first place: it is PPro so
no mixed silicon revisions and thus it can simply use boot_cpu_data.

Reported-by: Fengguang Wu 
Tested-by: Fengguang Wu 
Fix-creation-mandated-by: Linus Torvalds 
Signed-off-by: Borislav Petkov 
Signed-off-by: Thomas Gleixner 
Cc: Robert Richter 
Cc: x86@kernel.org
Signed-off-by: Greg Kroah-Hartman

MIPS: AR7: Ensure that serial ports are properly set up

2017-11-15T16:13:13+00:00

commit b084116f8587b222a2c5ef6dcd846f40f24b9420 upstream.

Without UPF_FIXED_TYPE, the data from the PORT_AR7 uart_config entry is
never copied, resulting in a dead port.

Fixes: 154615d55459 ("MIPS: AR7: Use correct UART port type")
Signed-off-by: Oswald Buddenhagen 
[jonas.gorski: add Fixes tag]
Signed-off-by: Jonas Gorski 
Reviewed-by: Florian Fainelli 
Cc: Ralf Baechle 
Cc: Greg Kroah-Hartman 
Cc: Yoshihiro YUNOMAE 
Cc: Nicolas Schichan 
Cc: Oswald Buddenhagen 
Cc: linux-mips@linux-mips.org
Cc: linux-serial@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17543/
Signed-off-by: James Hogan 
Signed-off-by: Greg Kroah-Hartman

MIPS: AR7: Defer registration of GPIO

2017-11-15T16:13:13+00:00

commit e6b03ab63b4d270e0249f96536fde632409dc1dc upstream.

When called from prom init code, ar7_gpio_init() will fail as it will
call gpiochip_add() which relies on a working kmalloc() to alloc
the gpio_desc array and kmalloc is not useable yet at prom init time.

Move ar7_gpio_init() to ar7_register_devices() (a device_initcall)
where kmalloc works.

Fixes: 14e85c0e69d5 ("gpio: remove gpio_descs global array")
Signed-off-by: Jonas Gorski 
Reviewed-by: Florian Fainelli 
Cc: Ralf Baechle 
Cc: Greg Kroah-Hartman 
Cc: Yoshihiro YUNOMAE 
Cc: Nicolas Schichan 
Cc: linux-mips@linux-mips.org
Cc: linux-serial@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17542/
Signed-off-by: James Hogan 
Signed-off-by: Greg Kroah-Hartman

MIPS: SMP: Fix deadlock & online race

2017-11-15T16:13:12+00:00

commit 9e8c399a88f0b87e41a894911475ed2a8f8dff9e upstream.

Commit 6f542ebeaee0 ("MIPS: Fix race on setting and getting
cpu_online_mask") effectively reverted commit 8f46cca1e6c06 ("MIPS: SMP:
Fix possibility of deadlock when bringing CPUs online") and thus has
reinstated the possibility of deadlock.

The commit was based on testing of kernel v4.4, where the CPU hotplug
core code issued a BUG() if the starting CPU is not marked online when
the boot CPU returns from __cpu_up. The commit fixes this race (in
v4.4), but re-introduces the deadlock situation.

As noted in the commit message, upstream differs in this area. Commit
8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu bring itself fully up")
adds a completion event in the CPU hotplug core code, making this race
impossible. However, people were unhappy with relying on the core code
to do the right thing.

To address the issues both commits were trying to fix, add a second
completion event in the MIPS smp hotplug path. It removes the
possibility of a race, since the MIPS smp hotplug code now synchronises
both the boot and secondary CPUs before they return to the hotplug core
code. It also addresses the deadlock by ensuring that the secondary CPU
is not marked online before it's counters are synchronised.

This fix should also be backported to fix the race condition introduced
by the backport of commit 8f46cca1e6c06 ("MIPS: SMP: Fix possibility of
deadlock when bringing CPUs online"), through really that race only
existed before commit 8df3e07e7f21f ("cpu/hotplug: Let upcoming cpu
bring itself fully up").

Signed-off-by: Matt Redfearn 
Fixes: 6f542ebeaee0 ("MIPS: Fix race on setting and getting cpu_online_mask")
CC: Matija Glavinic Pecotic 
Patchwork: https://patchwork.linux-mips.org/patch/17376/
Signed-off-by: James Hogan 
[jhogan@kernel.org: Backported 4.1..4.9]
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix race on setting and getting cpu_online_mask

2017-11-15T16:13:12+00:00

commit 6f542ebeaee0ee552a902ce3892220fc22c7ec8e upstream.

While testing cpu hoptlug (cpu down and up in loops) on kernel 4.4, it was
observed that occasionally check for cpu online will fail in kernel/cpu.c,
_cpu_up:

https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/kernel/cpu.c?h=v4.4.79#n485
 518        /* Arch-specific enabling code. */
 519        ret = __cpu_up(cpu, idle);
 520
 521        if (ret != 0)
 522                goto out_notify;
 523        BUG_ON(!cpu_online(cpu));

Reason is race between start_secondary and _cpu_up. cpu_callin_map is set
before cpu_online_mask. In __cpu_up, cpu_callin_map is waited for, but cpu
online mask is not, resulting in race in which secondary processor started
and set cpu_callin_map, but not yet set the online mask,resulting in above
BUG being hit.

Upstream differs in the area. cpu_online check is in bringup_wait_for_ap,
which is after cpu reached AP_ONLINE_IDLE,where secondary passed its start
function. Nonetheless, fix makes start_secondary safe and not depending on
other locks throughout the code. It protects as well against cpu_online
checks put in between sometimes in the future.

Fix this by moving completion after all flags are set.

Signed-off-by: Matija Glavinic Pecotic 
Cc: Alexander Sverdlin 
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/16925/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: SMP: Use a completion event to signal CPU up

2017-11-15T16:13:12+00:00

commit a00eeede507c975087b7b8df8cf2c9f88ba285de upstream.

If a secondary CPU failed to start, for any reason, the CPU requesting
the secondary to start would get stuck in the loop waiting for the
secondary to be present in the cpu_callin_map.

Rather than that, use a completion event to signal that the secondary
CPU has started and is waiting to synchronise counters.

Since the CPU presence will no longer be marked in cpu_callin_map,
remove the redundant test from arch_cpu_idle_dead().

Signed-off-by: Matt Redfearn 
Cc: Maciej W. Rozycki 
Cc: Jiri Slaby 
Cc: Paul Gortmaker 
Cc: Chris Metcalf 
Cc: Thomas Gleixner 
Cc: Qais Yousef 
Cc: James Hogan 
Cc: Paul Burton 
Cc: Marcin Nowakowski 
Cc: Andrew Morton 
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/14502/
Signed-off-by: Ralf Baechle 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix CM region target definitions

2017-11-15T16:13:12+00:00

commit 6a6cba1d945a7511cdfaf338526871195e420762 upstream.

The default CM target field in the GCR_BASE register is encoded with 0
meaning memory & 1 being reserved. However the definitions we use for
those bits effectively get these two values backwards - likely because
they were copied from the definitions for the CM regions where the
target is encoded differently. This results in use setting up GCR_BASE
with the reserved target value by default, rather than targeting memory
as intended. Although we currently seem to get away with this it's not a
great idea to rely upon.

Fix this by changing our macros to match the documentated target values.

The incorrect encoding became used as of commit 9f98f3dd0c51 ("MIPS: Add
generic CM probe & access code") in the Linux v3.15 cycle, and was
likely carried forwards from older but unused code introduced by
commit 39b8d5254246 ("[MIPS] Add support for MIPS CMP platform.") in the
v2.6.26 cycle.

Fixes: 9f98f3dd0c51 ("MIPS: Add generic CM probe & access code")
Signed-off-by: Paul Burton 
Reported-by: Matt Redfearn 
Reviewed-by: James Hogan 
Cc: Matt Redfearn 
Cc: Ralf Baechle 
Cc: linux-mips@linux-mips.org
Cc:  # v3.15+
Patchwork: https://patchwork.linux-mips.org/patch/17562/
Signed-off-by: James Hogan 
[jhogan@kernel.org: Backported 3.15..4.13]
Signed-off-by: Greg Kroah-Hartman

MIPS: microMIPS: Fix incorrect mask in insn_table_MM

2017-11-15T16:13:12+00:00

commit 77238e76b9156d28d86c1e31c00ed2960df0e4de upstream.

It seems that this is a typo error and the proper bit masking is
"RT | RS" instead of "RS | RS".

This issue was detected with the help of Coccinelle.

Fixes: d6b3314b49e1 ("MIPS: uasm: Add lh uam instruction")
Reported-by: Julia Lawall 
Signed-off-by: Gustavo A. R. Silva 
Reviewed-by: James Hogan 
Patchwork: https://patchwork.linux-mips.org/patch/17551/
Signed-off-by: James Hogan 
[jhogan@kernel.org: Backported 3.16..4.12]
Signed-off-by: Greg Kroah-Hartman

ARM: 8720/1: ensure dump_instr() checks addr_limit

2017-11-15T16:13:12+00:00

commit b9dd05c7002ee0ca8b676428b2268c26399b5e31 upstream.

When CONFIG_DEBUG_USER is enabled, it's possible for a user to
deliberately trigger dump_instr() with a chosen kernel address.

Let's avoid problems resulting from this by using get_user() rather than
__get_user(), ensuring that we don't erroneously access kernel memory.

So that we can use the same code to dump user instructions and kernel
instructions, the common dumping code is factored out to __dump_instr(),
with the fs manipulated appropriately in dump_instr() around calls to
this.

Signed-off-by: Mark Rutland 
Signed-off-by: Russell King 
Signed-off-by: Greg Kroah-Hartman