LLVM stack generates GOT table when building the kernel:

ld.lld: warning: <internal>:(.got) is being placed in '.got'

According to the debug assertions, it's not zero-sized and thus can't
be handled the way it's done for x86.
Also use the ARM64 path here and place it at the end of .text section.
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

According to linker warnings, both GCC and LLVM generate '.rel.dyn'
symbols:

mips-alpine-linux-musl-ld: warning: orphan section `.rel.dyn'
from `init/main.o' being placed in section `.rel.dyn'

Link-time assertion shows that this section is sometimes empty,
sometimes not, depending on machine bitness and the compiler [0]:

  LD      .tmp_vmlinux.kallsyms1
mips64-linux-gnu-ld: Unexpected run-time relocations (.rel) detected!

Just use the ARM64 approach and declare it in vmlinux.lds.S closer
to __init_end.

[0] https://lore.kernel.org/linux-mips/20210109111259.GA4213@alpha.franken.deReported-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Commit 866b6a89 ("MIPS: Add DWARF unwinding to assembly") added
-fno-asynchronous-unwind-tables to KBUILD_CFLAGS to prevent compiler
from emitting .eh_frame symbols.
However, as MIPS heavily uses CFI, that's not enough. Use the
approach taken for x86 (as it also uses CFI) and explicitly put CFI
symbols into the .debug_frame section (except for VDSO).
This allows us to drop .eh_frame from DISCARDS as it's no longer
being generated.

Fixes: 866b6a89 ("MIPS: Add DWARF unwinding to assembly")
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Discard GNU attributes (MIPS FP type, GNU Hash etc.) at link time
as kernel doesn't use it at all.
Solves a dozen of the following ld warnings (one per every file):

mips-alpine-linux-musl-ld: warning: orphan section `.gnu.attributes'
from `arch/mips/kernel/head.o' being placed in section
`.gnu.attributes'
mips-alpine-linux-musl-ld: warning: orphan section `.gnu.attributes'
from `init/main.o' being placed in section `.gnu.attributes'
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

A number of symbols from arch/mips/kernel/cps-vec.S is explicitly
placed into '.text.cps-vec' section.
There are no direct references to this section, so there's no need
to form it. '.balign 0x1000' directive will work anyway.

Moreover, this section was being placed in vmlinux differently
depending on CONFIG_LD_DEAD_CODE_DATA_ELIMINATION:
 - with this option enabled, '.text.cps-vec' was being caught
   by '.text.[0-9a-zA-Z_]*' from include/asm-generic/vmlinux.lds.h;
 - without this option, '.text.cps-vec' was being caught
   by discouraging '.text.*' from arch/mips/kernel/vmlinux.lds.S.

'.text.*' should not be used in vmlinux linker scripts at all as it
silently catches any orphan text sections.
So, remove both '.section .text.cps-vec' and '.text.*' from cps-vec.S
and vmlinux.lds.S respectively. As said, this does not affect related
functions alignment:

80116000 T mips_cps_core_entry
80116028 t not_nmi
80116200 T excep_tlbfill
80116280 T excep_xtlbfill
80116300 T excep_cache
80116380 T excep_genex
80116400 T excep_intex
80116480 T excep_ejtag
80116490 T mips_cps_core_init
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

MIPS uses its own declaration of rwdata, and thus it should be kept
in sync with the asm-generic one. Currently PAGE_ALIGNED_DATA() is
missing from the linker script, which emits the following ld
warnings:

mips-alpine-linux-musl-ld: warning: orphan section
`.data..page_aligned' from `arch/mips/kernel/vdso.o' being placed
in section `.data..page_aligned'
mips-alpine-linux-musl-ld: warning: orphan section
`.data..page_aligned' from `arch/mips/vdso/vdso-image.o' being placed
in section `.data..page_aligned'

Add the necessary declaration, so the mentioned structures will be
placed in vmlinux as intended:

ffffffff80630580 D __end_once
ffffffff80630580 D __start___dyndbg
ffffffff80630580 D __start_once
ffffffff80630580 D __stop___dyndbg
ffffffff80634000 d mips_vdso_data
ffffffff80638000 d vdso_data
ffffffff80638580 D _gp
ffffffff8063c000 T __init_begin
ffffffff8063c000 D _edata
ffffffff8063c000 T _sinittext

->

ffffffff805a4000 D __end_init_task
ffffffff805a4000 D __nosave_begin
ffffffff805a4000 D __nosave_end
ffffffff805a4000 d mips_vdso_data
ffffffff805a8000 d vdso_data
ffffffff805ac000 D mmlist_lock
ffffffff805ac080 D tasklist_lock

Fixes: ebb5e78c ("MIPS: Initial implementation of a VDSO")
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Cc: stable@vger.kernel.org # 4.4+
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Add support for more interrupt controllers by switching from
of_irq_init() to irqchip_init() in Lantiq's arch_init_irq(). This
requires switching the ICU interrupt controller to use
IRQCHIP_DECLARE(), like a real irqchip driver would do.

This is needed for future changes when new irqchip drivers are
implemented:
- a dedicated driver for the EIU interrupt controller
- a driver for the MSI PIC (Programmable Interrupt Controller) found on
  VRX200 and newer SoCs
- ..or any other driver which uses IRQCHIP_DECLARE
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Document the Lantiq Xway SoC DMA Controller DT bindings.
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Document the Lantiq Xway SoC series External Bus Unit (EBU) bindings.
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Document the Lantiq Xway SoC series Clock Generation Unit (CGU) bindings.
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Document the Lantiq Xway SoC series Power Management Unit (PMU) bindings.
Signed-off-by: Aleksander Jan Bajkowski <olek2@wp.pl>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Unlike most other architectures, MIPS defines ffz() below ffs().
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

unistd_nr_{n32,n64,o32}.h are needed only by include/asm/unistd.h,
which is a kernel-side header file, and their contents is generally
not for userland use.
Move their target destination from include/generated/uapi/asm/ to
include/generated/asm/ to disable exporting them as UAPI headers.
Signed-off-by: Alexander Lobakin <alobakin@pm.me>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

When building xway_defconfig with clang:

arch/mips/lantiq/irq.c:305:48: error: use of logical '&&' with constant
operand [-Werror,-Wconstant-logical-operand]
        if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0) && LTQ_EBU_PCC_ISTAT)
                                                      ^ ~~~~~~~~~~~~~~~~~
arch/mips/lantiq/irq.c:305:48: note: use '&' for a bitwise operation
        if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0) && LTQ_EBU_PCC_ISTAT)
                                                      ^~
                                                      &
arch/mips/lantiq/irq.c:305:48: note: remove constant to silence this
warning
        if ((irq == LTQ_ICU_EBU_IRQ) && (module == 0) && LTQ_EBU_PCC_ISTAT)
                                                     ~^~~~~~~~~~~~~~~~~~~~
1 error generated.

Explicitly compare the constant LTQ_EBU_PCC_ISTAT against 0 to fix the
warning. Additionally, remove the unnecessary parentheses as this is a
simple conditional statement and shorthand '== 0' to '!'.

Fixes: 3645da02 ("OF: MIPS: lantiq: implement irq_domain support")
Link: https://github.com/ClangBuiltLinux/linux/issues/807Reported-by: Dmitry Golovin <dima@golovin.in>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

This commit fixes the following checkpatch warnings:

    WARNING: externs should be avoided in .c files

    This is a warning for placing declarations in a ".c" file.
    This fix removes the declaration in ".c" and adds it to
    the common header file.
Signed-off-by: Yanteng Si <siyanteng@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Commit 2ee1503e ("MIPS: zboot: head.S clean up").

After .noreorder removed, clear BSS fall into endless loop. The bne
instruction will add nop to the delay slot at compile time. So a0
register will not increment by 4. Fix it and clear BSS from _edata
to (_end - 1).
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Most of the prom_free_prom_memory functions are empty. With
a new weak prom_free_prom_memory() we can remove all of them.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>

When building with clang, the following section mismatch warning occurs:

WARNING: modpost: vmlinux.o(.text+0x24490): Section mismatch in
reference from the function r4k_cache_init() to the function
.init.text:loongson2_sc_init()

This should have been fixed with commit ad4fddef ("mips: fix Section
mismatch in reference") but it was missed. Remove the improper __init
annotation like that commit did.

Fixes: 078a55fc ("MIPS: Delete __cpuinit/__CPUINIT usage from MIPS code")
Link: https://github.com/ClangBuiltLinux/linux/issues/787Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

When building xway_defconfig with clang:

arch/mips/lantiq/prom.c:82:23: error: array comparison always evaluates
to true [-Werror,-Wtautological-compare]
        else if (__dtb_start != __dtb_end)
                             ^
1 error generated.

These are not true arrays, they are linker defined symbols, which are
just addresses. Using the address of operator silences the warning
and does not change the resulting assembly with either clang/ld.lld
or gcc/ld (tested with diff + objdump -Dr). Do the same thing across
the entire MIPS subsystem to ensure there are no more warnings around
this type of comparison.

Link: https://github.com/ClangBuiltLinux/linux/issues/1232Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

This patch fixes:
"WARNING: Block comments use a trailing */ on a separate line"
by checkpatch.pl
Signed-off-by: siyanteng <siyanteng@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

RM7000 IRQ driver never got really used by any of the platform,
and rm9k_cpu_irq_init only exist in a header.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

According to Hardware Reference Manual, OCTEON III
are mostly same as previous OCTEON models. So just
enable them and extend supported event code.
0x3e and 0x3f still reserved.
Signed-off-by: Jia Qingtong <jiaqingtong97@163.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

cluster is required for cacheinfo to set shared_cpu_map correctly.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Victim Cache is defined by Loongson as per-core unified
private Cache.
Add this into cacheinfo and make cache levels selfincrement
instead of hardcode levels.
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Tested-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

.cprestore is removed as we don't expect Position Independent
zboot ELF.

.noreorder is also removed and rest instructions are massaged
to improve readability.

t9 register is used for indirect jump as MIPS ABI requirement.

start label is removed as it already defined in LEAF.
Reported-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Reviewed-by: Huacai Chen <chenhuacai@kernel.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

In the current code, we can not build under !CONFIG_NUMA and !CONFIG_SMP
on the Loongson64 platform, it seems bad for the users who just want to
use pure single core (not nosmp) to debug, so do the following things to
give them a chance:

(1) Do not select NUMA and SMP for MACH_LOONGSON64 in Kconfig, make NUMA
depends on SMP, and then just set them in the loongson3_defconfig.
(2) Move szmem() from numa.c to init.c and add prom_init_memory() under
!CONFIG_NUMA.
(3) Clean up szmem() due to the statements of case SYSTEM_RAM_LOW and
SYSTEM_RAM_HIGH are the same.
(4) Remove the useless declaration of prom_init_memory() and add the
declaration of szmem() in loongson.h to avoid build error.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

After commit 9cce844a ("MIPS: CPU#0 is not hotpluggable"),
c->hotpluggable is 0 for CPU 0 and it will not generate a control
file in sysfs for this CPU:

[root@linux loongson]# cat /sys/devices/system/cpu/cpu0/online
cat: /sys/devices/system/cpu/cpu0/online: No such file or directory
[root@linux loongson]# echo 0 > /sys/devices/system/cpu/cpu0/online
bash: /sys/devices/system/cpu/cpu0/online: Permission denied

So no need to check CPU 0 in cps_cpu_disable(), just remove it.
Reported-by: liwei (GF) <liwei391@huawei.com>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Replace a comma between expression statements by a semicolon.
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Replace a comma between expression statements by a semicolon.
Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

Since commit 36e2c742 ("fs: don't allow splice read/write without
explicit ops") we've required that file operation structures explicitly
enable splice support, rather than falling back to the default handlers.

Most /proc files use the indirect 'struct proc_ops' to describe their
file operations, and were fixed up to support splice earlier in commits
40be821d..b24c30c6, but the mountinfo files interact with the
VFS directly using their own 'struct file_operations' and got missed as
a result.

This adds the necessary support for splice to work for /proc/*/mountinfo
and friends.
Reported-by: Joan Bruguera Micó <joanbrugueram@gmail.com>
Reported-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=209971
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull NTB fixes from Jon Mason:
 "Bug fix for IDT NTB and Intel NTB LTR management support"

* tag 'ntb-5.11' of git://github.com/jonmason/ntb:
  ntb: intel: add Intel NTB LTR vendor support for gen4 NTB
  ntb: idt: fix error check in ntb_hw_idt.c

Pull crypto fixes from Herbert Xu:
 "Fix a number of autobuild failures due to missing Kconfig
  dependencies"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: qat - add CRYPTO_AES to Kconfig dependencies
  crypto: keembay - Add dependency on HAS_IOMEM
  crypto: keembay - CRYPTO_DEV_KEEMBAY_OCS_AES_SM4 should depend on ARCH_KEEMBAY

Pull objtool fix from Ingo Molnar:
 "Fix a segfault that occurs when built with Clang"

* tag 'objtool-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix seg fault with Clang non-section symbols

Pull locking fixes from Ingo Molnar:
 "Misc fixes/updates:

   - Fix static keys usage in module __init sections

   - Add separate MAINTAINERS entry for static branches/calls

   - Fix lockdep splat with CONFIG_PREEMPTIRQ_EVENTS=y tracing"

* tag 'locking-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  softirq: Avoid bad tracing / lockdep interaction
  jump_label/static_call: Add MAINTAINERS
  jump_label: Fix usage in module __init

Pull timer fixes from Ingo Molnar:
 "Update/fix two CPU sanity checks in the hotplug and the boot code, and
  fix a typo in the Kconfig help text.

  [ Context: the first two commits are the result of an ongoing
    annotation+review work of (intentional) tick_do_timer_cpu() data
    races reported by KCSAN, but the annotations aren't fully cooked
    yet ]"

* tag 'timers-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Fix spelling mistake in Kconfig "fullfill" -> "fulfill"
  tick/sched: Remove bogus boot "safety" check
  tick: Remove pointless cpu valid check in hotplug code

Pull scheduler fix from Ingo Molnar:
 "Fix a context switch performance regression"

* tag 'sched-urgent-2020-12-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Optimize finish_lock_switch()

Commit c9a3c4e6 ("mfd: ab8500-debugfs: Remove extraneous curly
brace") removed a left-over curly brace that caused build failures, but
Joe Perches points out that the subsequent 'seq_putc()' should also be
removed, because the commit that caused all these problems already added
the final '\n' to the seq_printf() above it.
Reported-by: Joe Perches <joe@perches.com>
Fixes: 886c8121 ("mfd: ab8500-debugfs: Remove the racy fiddling with irq_desc")
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull PCI fixes from Bjorn Helgaas:

 - Fix a tegra enumeration regression (Rob Herring)

 - Fix a designware-host check that warned on *success*, not failure
   (Alexander Lobakin)

* tag 'pci-v5.11-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: dwc: Fix inverted condition of DMA mask setup warning
  PCI: tegra: Fix host link initialization

Clang errors:

  drivers/mfd/ab8500-debugfs.c:1526:2: error: non-void function does not return a value [-Werror,-Wreturn-type]
          }
          ^
  drivers/mfd/ab8500-debugfs.c:1528:2: error: expected identifier or '('
  return 0;
          ^
  drivers/mfd/ab8500-debugfs.c:1529:1: error: extraneous closing brace ('}')
  }
  ^
  3 errors generated.

The cleanup in ab8500_interrupts_show left a curly brace around, remove
it to fix the error.

Fixes: 886c8121 ("mfd: ab8500-debugfs: Remove the racy fiddling with irq_desc")
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>