linux-stable.git/arch/xtensa, branch v4.19.78

xtensa: add missing isync to the cpu_reset TLB code

2019-08-25T08:47:47+00:00

commit cd8869f4cb257f22b89495ca40f5281e58ba359c upstream.

ITLB entry modifications must be followed by the isync instruction
before the new entries are possibly used. cpu_reset lacks one isync
between ITLB way 6 initialization and jump to the identity mapping.
Add missing isync to xtensa cpu_reset.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: Fix section mismatch between memblock_reserve and mem_reserve

2019-06-25T03:35:56+00:00

[ Upstream commit adefd051a6707a6ca0ebad278d3c1c05c960fc3b ]

Since commit 9012d011660ea5cf2 ("compiler: allow all arches to enable
CONFIG_OPTIMIZE_INLINING"), xtensa:tinyconfig fails to build with section
mismatch errors.

WARNING: vmlinux.o(.text.unlikely+0x68): Section mismatch in reference
	from the function ___pa()
	to the function .meminit.text:memblock_reserve()
WARNING: vmlinux.o(.text.unlikely+0x74): Section mismatch in reference
	from the function mem_reserve()
	to the function .meminit.text:memblock_reserve()
FATAL: modpost: Section mismatches detected.

This was not seen prior to the above mentioned commit because mem_reserve()
was always inlined.

Mark mem_reserve(() as __init_memblock to have it reside in the same
section as memblock_reserve().

Signed-off-by: Guenter Roeck 
Message-Id: <1559220098-9955-1-git-send-email-linux@roeck-us.net>
Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: fix return_address

2019-04-17T06:38:53+00:00

commit ada770b1e74a77fff2d5f539bf6c42c25f4784db upstream.

return_address returns the address that is one level higher in the call
stack than requested in its argument, because level 0 corresponds to its
caller's return address. Use requested level as the number of stack
frames to skip.

This fixes the address reported by might_sleep and friends.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: SMP: limit number of possible CPUs by NR_CPUS

2019-03-13T21:02:29+00:00

[ Upstream commit 25384ce5f9530def39421597b1457d9462df6455 ]

This fixes the following warning at boot when the kernel is booted on a
board with more CPU cores than was configured in NR_CPUS:

  smp_init_cpus: Core Count = 8
  smp_init_cpus: Core Id = 0
  ------------[ cut here ]------------
  WARNING: CPU: 0 PID: 0 at include/linux/cpumask.h:121 smp_init_cpus+0x54/0x74
  Modules linked in:
  CPU: 0 PID: 0 Comm: swapper Not tainted 5.0.0-rc3-00015-g1459333f88a0 #124
  Call Trace:
    __warn$part$3+0x6a/0x7c
    warn_slowpath_null+0x35/0x3c
    smp_init_cpus+0x54/0x74
    setup_arch+0x1c0/0x1d0
    start_kernel+0x44/0x310
    _startup+0x107/0x107

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: SMP: mark each possible CPU as present

2019-03-13T21:02:28+00:00

[ Upstream commit 8b1c42cdd7181200dc1fff39dcb6ac1a3fac2c25 ]

Otherwise it is impossible to enable CPUs after booting with 'maxcpus'
parameter.

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: smp_lx200_defconfig: fix vectors clash

2019-03-13T21:02:28+00:00

[ Upstream commit 306b38305c0f86de7f17c5b091a95451dcc93d7d ]

Secondary CPU reset vector overlaps part of the double exception handler
code, resulting in weird crashes and hangups when running user code.
Move exception vectors one page up so that they don't clash with the
secondary CPU reset vector.

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: SMP: fix secondary CPU initialization

2019-03-13T21:02:28+00:00

[ Upstream commit 32a7726c4f4aadfabdb82440d84f88a5a2c8fe13 ]

- add missing memory barriers to the secondary CPU synchronization spin
  loops; add comment to the matching memory barrier in the boot_secondary
  and __cpu_die functions;
- use READ_ONCE/WRITE_ONCE to access cpu_start_id/cpu_start_ccount
  instead of reading/writing them directly;
- re-initialize cpu_running every time before starting secondary CPU to
  flush possible previous CPU startup results.

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: SMP: fix ccount_timer_shutdown

2019-03-13T21:02:28+00:00

[ Upstream commit 4fe8713b873fc881284722ce4ac47995de7cf62c ]

ccount_timer_shutdown is called from the atomic context in the
secondary_start_kernel, resulting in the following BUG:

BUG: sleeping function called from invalid context
in_atomic(): 1, irqs_disabled(): 1, pid: 0, name: swapper/1
Preemption disabled at:
  secondary_start_kernel+0xa1/0x130
Call Trace:
  ___might_sleep+0xe7/0xfc
  __might_sleep+0x41/0x44
  synchronize_irq+0x24/0x64
  disable_irq+0x11/0x14
  ccount_timer_shutdown+0x12/0x20
  clockevents_switch_state+0x82/0xb4
  clockevents_exchange_device+0x54/0x60
  tick_check_new_device+0x46/0x70
  clockevents_register_device+0x8c/0xc8
  clockevents_config_and_register+0x1d/0x2c
  local_timer_setup+0x75/0x7c
  secondary_start_kernel+0xb4/0x130
  should_never_return+0x32/0x35

Use disable_irq_nosync instead of disable_irq to avoid it.
This is safe because the ccount timer IRQ is per-CPU, and once IRQ is
masked the ISR will not be called.

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin

xtensa: fix get_wchan

2019-03-10T06:17:21+00:00

commit d90b88fd3653f1fb66ecc6571b860d5a5749fa56 upstream.

Stack unwinding is implemented incorrectly in xtensa get_wchan: instead
of extracting a0 and a1 registers from the spill location under the
stack pointer it extracts a word pointed to by the stack pointer and
subtracts 4 or 3 from it.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov 
Signed-off-by: Greg Kroah-Hartman

xtensa: xtfpga.dtsi: fix dtc warnings about SPI

2019-02-12T18:47:05+00:00

[ Upstream commit f37598be4e3896359e87c824be57ddddc280cc3f ]

Rename SPI controller node in the XTFPGA DTS to spi@...
This fixes the following build warnings:

arch/xtensa/boot/dts/kc705_nommu.dtb: Warning (spi_bus_bridge):
 /soc/spi-master@0d0a0000: node name for SPI buses should be 'spi'
arch/xtensa/boot/dts/kc705_nommu.dtb: Warning (spi_bus_reg):
 Failed prerequisite 'spi_bus_bridge'
arch/xtensa/boot/dts/lx200mx.dtb: Warning (spi_bus_bridge):
 /soc/spi-master@0d0a0000: node name for SPI buses should be 'spi'
arch/xtensa/boot/dts/lx200mx.dtb: Warning (spi_bus_reg):
 Failed prerequisite 'spi_bus_bridge'
arch/xtensa/boot/dts/kc705.dtb: Warning (spi_bus_bridge):
 /soc/spi-master@0d0a0000: node name for SPI buses should be 'spi'
arch/xtensa/boot/dts/kc705.dtb: Warning (spi_bus_reg):
 Failed prerequisite 'spi_bus_bridge'
arch/xtensa/boot/dts/ml605.dtb: Warning (spi_bus_bridge):
 /soc/spi-master@0d0a0000: node name for SPI buses should be 'spi'
arch/xtensa/boot/dts/ml605.dtb: Warning (spi_bus_reg):
 Failed prerequisite 'spi_bus_bridge'
arch/xtensa/boot/dts/lx60.dtb: Warning (spi_bus_bridge):
 /soc/spi-master@0d0a0000: node name for SPI buses should be 'spi'
arch/xtensa/boot/dts/lx60.dtb: Warning (spi_bus_reg):
 Failed prerequisite 'spi_bus_bridge'

Signed-off-by: Max Filippov 
Signed-off-by: Sasha Levin