linux-stable.git/arch/arc, branch v5.9.8

ARC: stack unwinding: avoid indefinite looping

2020-11-10T11:39:10+00:00

commit 328d2168ca524d501fc4b133d6be076142bd305c upstream.

Currently stack unwinder is a while(1) loop which relies on the dwarf
unwinder to signal termination, which in turn relies on dwarf info to do
so. This in theory could cause an infinite loop if the dwarf info was
somehow messed up or the register contents were etc.

This fix thus detects the excessive looping and breaks the loop.

| Mem: 26184K used, 1009136K free, 0K shrd, 0K buff, 14416K cached
| CPU:  0.0% usr 72.8% sys  0.0% nic 27.1% idle  0.0% io  0.0% irq  0.0% sirq
| Load average: 4.33 2.60 1.11 2/74 139
|   PID  PPID USER     STAT   VSZ %VSZ CPU %CPU COMMAND
|   133     2 root     SWN      0  0.0   3 22.9 [rcu_torture_rea]
|   132     2 root     SWN      0  0.0   0 22.0 [rcu_torture_rea]
|   131     2 root     SWN      0  0.0   3 21.5 [rcu_torture_rea]
|   126     2 root     RW       0  0.0   2  5.4 [rcu_torture_wri]
|   129     2 root     SWN      0  0.0   0  0.2 [rcu_torture_fak]
|   137     2 root     SW       0  0.0   0  0.2 [rcu_torture_cbf]
|   127     2 root     SWN      0  0.0   0  0.1 [rcu_torture_fak]
|   138   115 root     R     1464  0.1   2  0.1 top
|   130     2 root     SWN      0  0.0   0  0.1 [rcu_torture_fak]
|   128     2 root     SWN      0  0.0   0  0.1 [rcu_torture_fak]
|   115     1 root     S     1472  0.1   1  0.0 -/bin/sh
|   104     1 root     S     1464  0.1   0  0.0 inetd
|     1     0 root     S     1456  0.1   2  0.0 init
|    78     1 root     S     1456  0.1   0  0.0 syslogd -O /var/log/messages
|   134     2 root     SW       0  0.0   2  0.0 [rcu_torture_sta]
|    10     2 root     IW       0  0.0   1  0.0 [rcu_preempt]
|    88     2 root     IW       0  0.0   1  0.0 [kworker/1:1-eve]
|    66     2 root     IW       0  0.0   2  0.0 [kworker/2:2-eve]
|    39     2 root     IW       0  0.0   2  0.0 [kworker/2:1-eve]
| unwinder looping too long, aborting !

Cc: 
Signed-off-by: Vineet Gupta 
Signed-off-by: Greg Kroah-Hartman

ARC: perf: redo the pct irq missing in device-tree handling

2020-11-05T10:51:47+00:00

commit 8c42a5c02bec6c7eccf08957be3c6c8fccf9790b upstream.

commit feb92d7d3813456c11dce21 "(ARC: perf: don't bail setup if pct irq
missing in device-tree)" introduced a silly brown-paper bag bug:
The assignment and comparison in an if statement were not bracketed
correctly leaving the order of evaluation undefined.

|
| if (has_interrupts && (irq = platform_get_irq(pdev, 0) >= 0)) {
|                           ^^^                         ^^^^

And given such a chance, the compiler will bite you hard, fully entitled
to generating this piece of beauty:

|
| # if (has_interrupts && (irq = platform_get_irq(pdev, 0) >= 0)) {
|
| bl.d @platform_get_irq  <-- irq returned in r0
|
| setge r2, r0, 0   	<-- r2 is bool 1 or 0 if irq >= 0 true/false
| brlt.d r0, 0, @.L114
|
| st_s	r2,[sp]    	<-- irq saved is bool 1 or 0, not actual return val
| st	1,[r3,160]   	# arc_pmu.18_29->irq <-- drops bool and assumes 1
|
| # return __request_percpu_irq(irq, handler, 0,
|
| bl.d @__request_percpu_irq;
| mov_s	r0,1	   <-- drops even bool and assumes 1 which fails

With the snafu fixed, everything is as expected.

| bl.d @platform_get_irq	<-- returns irq in r0
|
| mov_s	r2,r0
| brlt.d r2, 0, @.L112
|
| st_s	r0,[sp]			<-- irq isaved is actual return value above
| st	r0,[r13,160]	#arc_pmu.18_27->irq
|
| bl.d @__request_percpu_irq	<-- r0 unchanged so actual irq returned
| add r4,r4,r12	#, tmp363, __ptr

Cc: 
Signed-off-by: Vineet Gupta 
Signed-off-by: Greg Kroah-Hartman

ARC: [dts] fix the errors detected by dtbs_check

2020-11-05T10:51:25+00:00

[ Upstream commit 05b1be68c4d6d76970025e6139bfd735c2256ee5 ]

xxx/arc/boot/dts/axs101.dt.yaml: dw-apb-ictl@e0012000: $nodename:0: \
'dw-apb-ictl@e0012000' does not match '^interrupt-controller(@[0-9a-f,]+)*$'
 From schema: xxx/interrupt-controller/snps,dw-apb-ictl.yaml

The node name of the interrupt controller must start with
"interrupt-controller" instead of "dw-apb-ictl".

Signed-off-by: Zhen Lei 
Signed-off-by: Vineet Gupta 
Signed-off-by: Sasha Levin

arc: plat-hsdk: fix kconfig dependency warning when !RESET_CONTROLLER

2020-10-29T09:11:40+00:00

[ Upstream commit 63bcf87cb1c57956e1179f1a78dde625c7e3cba7 ]

When ARC_SOC_HSDK is enabled and RESET_CONTROLLER is disabled, it results
in the following Kbuild warning:

WARNING: unmet direct dependencies detected for RESET_HSDK
  Depends on [n]: RESET_CONTROLLER [=n] && HAS_IOMEM [=y] && (ARC_SOC_HSDK [=y] || COMPILE_TEST [=n])
  Selected by [y]:
  - ARC_SOC_HSDK [=y] && ISA_ARCV2 [=y]

The reason is that ARC_SOC_HSDK selects RESET_HSDK without depending on or
selecting RESET_CONTROLLER while RESET_HSDK is subordinate to
RESET_CONTROLLER.

Honor the kconfig menu hierarchy to remove kconfig dependency warnings.

Fixes: a528629dfd3b ("ARC: [plat-hsdk] select CONFIG_RESET_HSDK from Kconfig")
Signed-off-by: Necip Fazil Yildiran 
Signed-off-by: Vineet Gupta 
Signed-off-by: Sasha Levin

Merge tag 'arc-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc

2020-09-05T20:46:14+00:00

Pull ARC fixes from Vineet Gupta:

 - HSDK-4xd Dev system: perf driver updates for sampling interrupt

 - HSDK* Dev System: Ethernet broken [Evgeniy Didin]

 - HIGHMEM broken (2 memory banks) [Mike Rapoport]

 - show_regs() rewrite once and for all

 - Other minor fixes

* tag 'arc-5.9-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
  ARC: [plat-hsdk]: Switch ethernet phy-mode to rgmii-id
  arc: fix memory initialization for systems with two memory banks
  irqchip/eznps: Fix build error for !ARC700 builds
  ARC: show_regs: fix r12 printing and simplify
  ARC: HSDK: wireup perf irq
  ARC: perf: don't bail setup if pct irq missing in device-tree
  ARC: pgalloc.h: delete a duplicated word + other fixes

ARC: [plat-hsdk]: Switch ethernet phy-mode to rgmii-id

2020-09-01T18:59:04+00:00

HSDK board has Micrel KSZ9031, recent commit
bcf3440c6dd ("net: phy: micrel: add phy-mode support for the KSZ9031 PHY")
caused a breakdown of Ethernet.
Using 'phy-mode = "rgmii"' is not correct because accodring RGMII
specification it is necessary to have delay on RX (PHY to MAX)
which is not generated in case of "rgmii".
Using "rgmii-id" adds necessary delay and solves the issue.

Also adding name of PHY placed on HSDK board.

Signed-off-by: Evgeniy Didin 
Cc: Eugeniy Paltsev 
Cc: Alexey Brodkin 
Signed-off-by: Vineet Gupta

arc: fix memory initialization for systems with two memory banks

2020-09-01T18:23:50+00:00

Rework of memory map initialization broke initialization of ARC systems
with two memory banks. Before these changes, memblock was not aware of
nodes configuration and the memory map was always allocated from the
"lowmem" bank. After the addition of node information to memblock, the core
mm attempts to allocate the memory map for the "highmem" bank from its
node. The access to this memory using __va() fails because it can be only
accessed using kmap.

Anther problem that was uncovered is that {min,max}_high_pfn are calculated
from u64 high_mem_start variable which prevents truncation to 32-bit
physical address and the PFN values are above the node and zone boundaries.

Use phys_addr_t type for high_mem_start and high_mem_size to ensure
correspondence between PFNs and highmem zone boundaries and reserve the
entire highmem bank until mem_init() to avoid accesses to it before highmem
is enabled.

To test this:
1. Enable HIGHMEM in ARC config
2. Enable 2 memory banks in haps_hs.dts (uncomment the 2nd bank)

Fixes: 51930df5801e ("mm: free_area_init: allow defining max_zone_pfn in descending order")
Cc: stable@vger.kernel.org   [5.8]
Signed-off-by: Mike Rapoport 
Signed-off-by: Vineet Gupta 
[vgupta: added instructions to test highmem]

irqchip/eznps: Fix build error for !ARC700 builds

2020-08-27T20:15:17+00:00

eznps driver is supposed to be platform independent however it ends up
including stuff from inside arch/arc headers leading to rand config
build errors.

The quick hack to fix this (proper fix is too much chrun for non active
user-base) is to add following to nps platform agnostic header.
 - copy AUX_IENABLE from arch/arc header
 - move CTOP_AUX_IACK from arch/arc/plat-eznps/*/**

Reported-by: kernel test robot 
Reported-by: Sebastian Andrzej Siewior 
Link: https://lkml.kernel.org/r/20200824095831.5lpkmkafelnvlpi2@linutronix.de
Signed-off-by: Vineet Gupta

ARC: show_regs: fix r12 printing and simplify

2020-08-27T20:11:37+00:00

when working on ARC64, spotted an issue in ARCv2 reg file printing.
print_reg_file() assumes contiguous reg-file whereas in ARCv2 they are
not: r12 comes before r0-r11 due to hardware auto-save. Apparently this
issue has been present since v2 port submission.

To avoid bolting hacks for this discontinuity while looping through
pt_regs, just ditching the loop and print pt_regs directly.

Signed-off-by: Vineet Gupta

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva