Commit Graph

982015 Commits

Author SHA1 Message Date
Pavel Begunkov
a528b04ea4 io_uring: fix ignoring xa_store errors
xa_store() may fail, check the result.

Cc: stable@vger.kernel.org # 5.10
Fixes: 0f2122045b ("io_uring: don't rely on weak ->files references")
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-21 13:01:10 -07:00
Antonio Quartulli
52252adede dm ebs: avoid double unlikely() notation when using IS_ERR()
The definition of IS_ERR() already applies the unlikely() notation
when checking the error status of the passed pointer. For this
reason there is no need to have the same notation outside of
IS_ERR() itself.

Clean up code by removing redundant notation.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-12-21 13:59:37 -05:00
Hyeongseok Kim
252bd12563 dm verity: skip verity work if I/O error when system is shutting down
If emergency system shutdown is called, like by thermal shutdown,
a dm device could be alive when the block device couldn't process
I/O requests anymore. In this state, the handling of I/O errors
by new dm I/O requests or by those already in-flight can lead to
a verity corruption state, which is a misjudgment.

So, skip verity work in response to I/O error when system is shutting
down.

Signed-off-by: Hyeongseok Kim <hyeongseok@gmail.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2020-12-21 13:57:25 -05:00
Linus Torvalds
8653b778e4 The core framework got some nice improvements this time around. We gained the
ability to get struct clk pointers from a struct clk_hw so that clk providers
 can consume the clks they provide, if they need to do something like that. This
 has been a long missing part of the clk provider API that will help us move
 away from exposing a struct clk pointer in the struct clk_hw. Tracepoints are
 added for the clk_set_rate() "range" functions, similar to the tracepoints we
 already have for clk_set_rate() and we added a column to debugfs to help
 developers understand the hardware enable state of clks in case firmware or
 bootloader state is different than what is expected. Overall the core changes
 are mostly improving the clk driver writing experience.
 
 At the driver level, we have the usual collection of driver updates and new
 drivers for new SoCs. This time around the Qualcomm folks introduced a good
 handful of clk drivers for various parts of three or four SoCs. The SiFive
 folks added a new clk driver for their FU740 SoCs, coming in second on the
 diffstat and then Atmel AT91 and Amlogic SoCs had lots of work done after that
 for various new features. One last thing to note in the driver area is that the
 i.MX driver has gained a new binding to support SCU clks after being on the
 list for many months. It uses a two cell binding which is sort of rare in clk
 DT bindings. Beyond that we have the usual set of driver fixes and tweaks that
 come from more testing and finding out that some configuration was wrong or
 that a driver could support being built as a module.
 
 Core:
  - Add some trace points for clk_set_rate() "range" functions
  - Add hardware enable information to clk_summary debugfs
  - Replace clk-provider.h with of_clk.h when possible
  - Add devm variant of clk_notifier_register()
  - Add clk_hw_get_clk() to generate a struct clk from a struct clk_hw
 
 New Drivers:
  - Bindings for Canaan K210 SoC clks
  - Support for SiFive FU740 PRCI
  - Camera clks on Qualcomm SC7180 SoCs
  - GCC and RPMh clks on Qualcomm SDX55 SoCs
  - RPMh clks on Qualcomm SM8350 SoCs
  - LPASS clks on Qualcomm SM8250 SoCs
 
 Updates:
  - DVFS support for AT91 clk driver
  - Update git repo branch for Renesas clock drivers
  - Add camera (CSI) and video-in (VIN) clocks on Renesas R-Car V3U
  - Add RPC (QSPI/HyperFLASH) clocks on Renesas RZ/G2M, RZ/G2N, and RZ/G2E
  - Stop using __raw_*() I/O accessors in Renesas clk drivers
  - One more conversion of DT bindings to json-schema
  - Make i.MX clk-gate2 driver more flexible
  - New two cell binding for i.MX SCU clks
  - Drop of_match_ptr() in i.MX8 clk drivers
  - Add arch dependencies for Rockchip clk drivers
  - Fix i2s on Rockchip rk3066
  - Add MIPI DSI clks on Amlogic axg and g12 SoCs
  - Support modular builds of Amlogic clk drivers
  - Fix an Amlogic Video PLL clock dependency
  - Samsung Kconfig dependencies updates for better compile test coverage
  - Refactoring of the Samsung PLL clocks driver
  - Small Tegra driver cleanups
  - Minor fixes to Ingenic and VC5 clk drivers
  - Cleanup patches to remove unused variables and plug memory leaks
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Merge tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux

Pull clk updates from Stephen Boyd:
 "The core framework got some nice improvements this time around. We
  gained the ability to get struct clk pointers from a struct clk_hw so
  that clk providers can consume the clks they provide, if they need to
  do something like that. This has been a long missing part of the clk
  provider API that will help us move away from exposing a struct clk
  pointer in the struct clk_hw. Tracepoints are added for the
  clk_set_rate() "range" functions, similar to the tracepoints we
  already have for clk_set_rate() and we added a column to debugfs to
  help developers understand the hardware enable state of clks in case
  firmware or bootloader state is different than what is expected.
  Overall the core changes are mostly improving the clk driver writing
  experience.

  At the driver level, we have the usual collection of driver updates
  and new drivers for new SoCs. This time around the Qualcomm folks
  introduced a good handful of clk drivers for various parts of three or
  four SoCs. The SiFive folks added a new clk driver for their FU740
  SoCs, coming in second on the diffstat and then Atmel AT91 and Amlogic
  SoCs had lots of work done after that for various new features. One
  last thing to note in the driver area is that the i.MX driver has
  gained a new binding to support SCU clks after being on the list for
  many months. It uses a two cell binding which is sort of rare in clk
  DT bindings. Beyond that we have the usual set of driver fixes and
  tweaks that come from more testing and finding out that some
  configuration was wrong or that a driver could support being built as
  a module.

  Summary:

  Core:
   - Add some trace points for clk_set_rate() "range" functions
   - Add hardware enable information to clk_summary debugfs
   - Replace clk-provider.h with of_clk.h when possible
   - Add devm variant of clk_notifier_register()
   - Add clk_hw_get_clk() to generate a struct clk from a struct clk_hw

  New Drivers:
   - Bindings for Canaan K210 SoC clks
   - Support for SiFive FU740 PRCI
   - Camera clks on Qualcomm SC7180 SoCs
   - GCC and RPMh clks on Qualcomm SDX55 SoCs
   - RPMh clks on Qualcomm SM8350 SoCs
   - LPASS clks on Qualcomm SM8250 SoCs

  Updates:
   - DVFS support for AT91 clk driver
   - Update git repo branch for Renesas clock drivers
   - Add camera (CSI) and video-in (VIN) clocks on Renesas R-Car V3U
   - Add RPC (QSPI/HyperFLASH) clocks on Renesas RZ/G2M, RZ/G2N, and RZ/G2E
   - Stop using __raw_*() I/O accessors in Renesas clk drivers
   - One more conversion of DT bindings to json-schema
   - Make i.MX clk-gate2 driver more flexible
   - New two cell binding for i.MX SCU clks
   - Drop of_match_ptr() in i.MX8 clk drivers
   - Add arch dependencies for Rockchip clk drivers
   - Fix i2s on Rockchip rk3066
   - Add MIPI DSI clks on Amlogic axg and g12 SoCs
   - Support modular builds of Amlogic clk drivers
   - Fix an Amlogic Video PLL clock dependency
   - Samsung Kconfig dependencies updates for better compile test coverage
   - Refactoring of the Samsung PLL clocks driver
   - Small Tegra driver cleanups
   - Minor fixes to Ingenic and VC5 clk drivers
   - Cleanup patches to remove unused variables and plug memory leaks"

* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (134 commits)
  dt-binding: clock: Document canaan,k210-clk bindings
  dt-bindings: Add Canaan vendor prefix
  clk: vc5: Use "idt,voltage-microvolt" instead of "idt,voltage-microvolts"
  clk: ingenic: Fix divider calculation with div tables
  clk: sunxi-ng: Make sure divider tables have sentinel
  clk: s2mps11: Fix a resource leak in error handling paths in the probe function
  clk: mvebu: a3700: fix the XTAL MODE pin to MPP1_9
  clk: si5351: Wait for bit clear after PLL reset
  clk: at91: sam9x60: remove atmel,osc-bypass support
  clk: at91: sama7g5: register cpu clock
  clk: at91: clk-master: re-factor master clock
  clk: at91: sama7g5: do not allow cpu pll to go higher than 1GHz
  clk: at91: sama7g5: decrease lower limit for MCK0 rate
  clk: at91: sama7g5: remove mck0 from parent list of other clocks
  clk: at91: clk-sam9x60-pll: allow runtime changes for pll
  clk: at91: sama7g5: add 5th divisor for mck0 layout and characteristics
  clk: at91: clk-master: add 5th divisor for mck master
  clk: at91: sama7g5: allow SYS and CPU PLLs to be exported and referenced in DT
  dt-bindings: clock: at91: add sama7g5 pll defines
  clk: at91: sama7g5: fix compilation error
  ...
2020-12-21 10:39:37 -08:00
Linus Torvalds
8552d28e14 Fixes include:
. cleanup of 68328 code
 . align BSS section to 32bit
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Merge tag 'm68knommu-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu

Pull m68knommu updates from Greg Ungerer:

 - cleanup of 68328 code

 - align BSS section to 32bit

* tag 'm68knommu-for-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu:
  m68k: m68328: remove duplicate code
  m68k: m68328: move platform code to separate files
  m68knommu: align BSS section to 4-byte boundaries
2020-12-21 10:35:11 -08:00
Linus Torvalds
70990afa34 9p for 5.11-rc1
- fix long-standing limitation on open-unlink-fop pattern
 - add refcount to p9_fid (fixes the above and will allow for more
 cleanups and simplifications in the future)
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Merge tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux

Pull 9p update from Dominique Martinet:

 - fix long-standing limitation on open-unlink-fop pattern

 - add refcount to p9_fid (fixes the above and will allow for more
   cleanups and simplifications in the future)

* tag '9p-for-5.11-rc1' of git://github.com/martinetd/linux:
  9p: Remove unnecessary IS_ERR() check
  9p: Uninitialized variable in v9fs_writeback_fid()
  9p: Fix writeback fid incorrectly being attached to dentry
  9p: apply review requests for fid refcounting
  9p: add refcount to p9_fid struct
  fs/9p: search open fids first
  fs/9p: track open fids
  fs/9p: fix create-unlink-getattr idiom
2020-12-21 10:28:02 -08:00
Fengfei Xi
c635b0cea6 docs: admin-guide: Fix default value of max_map_count in sysctl/vm.rst
Since the default value of sysctl_max_map_count is defined as
DEFAULT_MAX_MAP_COUNT from mm/util.c

    int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;

DEFAULT_MAX_MAP_COUNT is defined as 65530 (65535-5) in include/linux/mm.h

    #define MAPCOUNT_ELF_CORE_MARGIN        (5)
    #define DEFAULT_MAX_MAP_COUNT   (USHRT_MAX - MAPCOUNT_ELF_CORE_MARGIN)

Signed-off-by: Fengfei Xi <xi.fengfei@h3c.com>
Link: https://lore.kernel.org/r/20201210082134.36957-1-xi.fengfei@h3c.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-21 09:59:07 -07:00
Borislav Petkov
9bf19b78a2 Documentation/submitting-patches: Document the SoB chain
Document what a chain of Signed-off-by's in a patch commit message
should mean, explicitly.

This has been carved out from a tip subsystem handbook patchset by
Thomas Gleixner:

  https://lkml.kernel.org/r/20181107171010.421878737@linutronix.de

and incorporates follow-on comments.

Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20201217183756.GE23634@zn.tnic
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-21 09:52:57 -07:00
Milan Lakhani
27ab873e0c Documentation: process: Correct numbering
Renumber the steps in submit-checklist.rst as some numbers were skipped.

Signed-off-by: Milan Lakhani <milan.lakhani@codethink.co.uk>
Link: https://lore.kernel.org/r/1608064956-5512-1-git-send-email-milan.lakhani@codethink.co.uk
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-21 09:47:00 -07:00
Lee Jones
7e90285716 docs: submitting-patches: Trivial - fix grammatical error
"it is a used" does not make sense.  Should be "it is used".

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20201216134654.271508-1-lee.jones@linaro.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-21 09:44:35 -07:00
Christophe Leroy
d5c243989f powerpc/32: Fix vmap stack - Properly set r1 before activating MMU on syscall too
We need r1 to be properly set before activating MMU, otherwise any new
exception taken while saving registers into the stack in syscall
prologs will use the user stack, which is wrong and will even lockup
or crash when KUAP is selected.

Do that by switching the meaning of r11 and r1 until we have saved r1
to the stack: copy r1 into r11 and setup the new stack pointer in r1.
To avoid complicating and impacting all generic and specific prolog
code (and more), copy back r1 into r11 once r11 is save onto
the stack.

We could get rid of copying r1 back and forth at the cost of rewriting
everything to use r1 instead of r11 all the way when CONFIG_VMAP_STACK
is set, but the effort is probably not worth it for now.

Fixes: da7bb43ab9 ("powerpc/32: Fix vmap stack - Properly set r1 before activating MMU")
Cc: stable@vger.kernel.org # v5.10+
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/a3d819d5c348cee9783a311d5d3f3ba9b48fd219.1608531452.git.christophe.leroy@csgroup.eu
2020-12-21 22:24:00 +11:00
Russell King
ecbbb88727 Merge branch 'devel-stable' into for-next 2020-12-21 11:19:26 +00:00
Russell King
8cc9251737 Merge branches 'fixes' and 'misc' into for-next 2020-12-21 11:19:24 +00:00
Ard Biesheuvel
10fce53c0e ARM: 9027/1: head.S: explicitly map DT even if it lives in the first physical section
The early ATAGS/DT mapping code uses SECTION_SHIFT to mask low order
bits of R2, and decides that no ATAGS/DTB were provided if the resulting
value is 0x0.

This means that on systems where DRAM starts at 0x0 (such as Raspberry
Pi), no explicit mapping of the DT will be created if R2 points into the
first 1 MB section of memory. This was not a problem before, because the
decompressed kernel is loaded at the base of DRAM and mapped using
sections as well, and so as long as the DT is referenced via a virtual
address that uses the same translation (the linear map, in this case),
things work fine.

However, commit 7a1be318f5 ("9012/1: move device tree mapping out of
linear region") changes this, and now the DT is referenced via a virtual
address that is disjoint from the linear mapping of DRAM, and so we need
the early code to create the DT mapping unconditionally.

So let's create the early DT mapping for any value of R2 != 0x0.

Reported-by: "kernelci.org bot" <bot@kernelci.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:21 +00:00
Nathan Chancellor
0cda9bc15d ARM: 9038/1: Link with '-z norelro'
When linking a multi_v7_defconfig + CONFIG_KASAN=y kernel with
LD=ld.lld, the following error occurs:

$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- LLVM=1 zImage
ld.lld: error: section: .exit.data is not contiguous with other relro sections

LLD defaults to '-z relro', which is unneeded for the kernel because
program headers are not used nor is there any position independent code
generation or linking for ARM. Add '-z norelro' to LDFLAGS_vmlinux to
avoid this error.

Link: https://github.com/ClangBuiltLinux/linux/issues/1189

Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:21 +00:00
Geert Uytterhoeven
551b39efc6 ARM: 9037/1: uncompress: Add OF_DT_MAGIC macro
The DTB magic marker is stored as a 32-bit big-endian value, and thus
depends on the CPU's endianness.  Add a macro to define this value in
native endianness, to reduce #ifdef clutter and (future) duplication.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:21 +00:00
Geert Uytterhoeven
1ecec38547 ARM: 9036/1: uncompress: Fix dbgadtb size parameter name
The dbgadtb macro is passed the size of the appended DTB, not the end
address.

Fixes: c03e41470e ("ARM: 9010/1: uncompress: Print the location of appended DTB")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:20 +00:00
Geert Uytterhoeven
0557ac83fd ARM: 9035/1: uncompress: Add be32tocpu macro
DTB stores all values as 32-bit big-endian integers.
Add a macro to convert such values to native CPU endianness, to reduce
duplication.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:20 +00:00
Anshuman Khandual
27bde183b0 ARM: 9033/1: arm/smp: Drop the macro S(x,s)
Mapping between IPI type index and its string is direct without requiring
an additional offset. Hence the existing macro S(x, s) is now redundant
and can just be dropped. This also makes the code clean and simple.

Cc: Marc Zyngier <maz@kernel.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:19 +00:00
Anshuman Khandual
76460d613d ARM: 9032/1: arm/mm: Convert PUD level pgtable helper macros into functions
Macros used as functions can be problematic from the compiler perspective.
There was a build failure report caused primarily because of non reference
of an argument variable. Hence convert PUD level pgtable helper macros into
functions in order to avoid such problems in the future. In the process, it

fixes the argument variables sequence in set_pud() which probably remained
hidden for being a macro.

https://lore.kernel.org/linux-mm/202011020749.5XQ3Hfzc-lkp@intel.com/
https://lore.kernel.org/linux-mm/5fa49698.Vu2O3r+dU20UoEJ+%25lkp@intel.com/

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:19 +00:00
Ard Biesheuvel
6c7a6d22fc ARM: 9031/1: hyp-stub: remove unused .L__boot_cpu_mode_offset symbol
Commit aaac373317 ("ARM: kvm: replace open coded VA->PA calculations
with adr_l call") removed all uses of .L__boot_cpu_mode_offset, so there
is no longer a need to define it.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:19 +00:00
Ard Biesheuvel
3cce9d4432 ARM: 9044/1: vfp: use undef hook for VFP support detection
Commit f77ac2e378 ("ARM: 9030/1: entry: omit FP emulation for UND
exceptions taken in kernel mode") failed to take into account that there
is in fact a case where we relied on this code path: during boot, the
VFP detection code issues a read of FPSID, which will trigger an undef
exception on cores that lack VFP support.

So let's reinstate this logic using an undef hook which is registered
only for the duration of the initcall to vpf_init(), and which sets
VFP_arch to a non-zero value - as before - if no VFP support is present.

Fixes: f77ac2e378 ("ARM: 9030/1: entry: omit FP emulation for UND ...")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2020-12-21 11:19:19 +00:00
Michael Ellerman
2eda7f1100 powerpc/vdso: Fix DOTSYM for 32-bit LE VDSO
Skirmisher reported on IRC that the 32-bit LE VDSO was hanging. This
turned out to be due to a branch to self in eg. __kernel_gettimeofday.
Looking at the disassembly with objdump -dR shows why:

  00000528 <__kernel_gettimeofday>:
   528:   f0 ff 21 94     stwu    r1,-16(r1)
   52c:   a6 02 08 7c     mflr    r0
   530:   f0 ff 21 94     stwu    r1,-16(r1)
   534:   14 00 01 90     stw     r0,20(r1)
   538:   05 00 9f 42     bcl     20,4*cr7+so,53c <__kernel_gettimeofday+0x14>
   53c:   a6 02 a8 7c     mflr    r5
   540:   ff ff a5 3c     addis   r5,r5,-1
   544:   c4 fa a5 38     addi    r5,r5,-1340
   548:   f0 00 a5 38     addi    r5,r5,240
   54c:   01 00 00 48     bl      54c <__kernel_gettimeofday+0x24>
                          54c: R_PPC_REL24        .__c_kernel_gettimeofday

Because we don't process relocations for the VDSO, this branch remains
a branch from 0x54c to 0x54c.

With the preceding patch to prohibit R_PPC_REL24 relocations, we
instead get a build failure:

  0000054c R_PPC_REL24       .__c_kernel_gettimeofday
  00000598 R_PPC_REL24       .__c_kernel_clock_gettime
  000005e4 R_PPC_REL24       .__c_kernel_clock_gettime64
  00000630 R_PPC_REL24       .__c_kernel_clock_getres
  0000067c R_PPC_REL24       .__c_kernel_time
  arch/powerpc/kernel/vdso32/vdso32.so.dbg: dynamic relocations are not supported

The root cause is that we're branching to `.__c_kernel_gettimeofday`.
But this is 32-bit LE code, which doesn't use function descriptors, so
there are no dot symbols.

The reason we're trying to branch to a dot symbol is because we're
using the DOTSYM macro, but the ifdefs we use to define the DOTSYM
macro do not currently work for 32-bit LE.

So like previous commits we need to differentiate if the current
compilation unit is 64-bit, rather than the kernel as a whole. ie.
switch from CONFIG_PPC64 to __powerpc64__.

With that fixed 32-bit LE code gets the empty version of DOTSYM, which
just resolves to the original symbol name, leading to a direct branch
and no relocations:

  000003f8 <__kernel_gettimeofday>:
   3f8:   f0 ff 21 94     stwu    r1,-16(r1)
   3fc:   a6 02 08 7c     mflr    r0
   400:   f0 ff 21 94     stwu    r1,-16(r1)
   404:   14 00 01 90     stw     r0,20(r1)
   408:   05 00 9f 42     bcl     20,4*cr7+so,40c <__kernel_gettimeofday+0x14>
   40c:   a6 02 a8 7c     mflr    r5
   410:   ff ff a5 3c     addis   r5,r5,-1
   414:   f4 fb a5 38     addi    r5,r5,-1036
   418:   f0 00 a5 38     addi    r5,r5,240
   41c:   85 06 00 48     bl      aa0 <__c_kernel_gettimeofday>

Fixes: ab037dd87a ("powerpc/vdso: Switch VDSO to generic C implementation.")
Reported-by: "Will Springer <skirmisher@protonmail.com>"
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201218111619.1206391-3-mpe@ellerman.id.au
2020-12-21 22:06:26 +11:00
Michael Ellerman
107521e803 powerpc/vdso: Don't pass 64-bit ABI cflags to 32-bit VDSO
When building the 32-bit VDSO, we are building 32-bit code as part of
a 64-bit kernel build. That requires us to tweak the cflags to trick
the compiler into building 32-bit code for us. The main way we do that
is by passing -m32, but there are other options that affect code
generation and ABI selection.

In particular when building vgettimeofday.c, we end up passing
-mcall-aixdesc because it's in KBUILD_CFLAGS, which causes the
compiler to generate function descriptors, and dot symbols, eg:

  $ nm arch/powerpc/kernel/vdso32/vgettimeofday.o
  000005d0 T .__c_kernel_clock_getres
  00000024 D __c_kernel_clock_getres
  ...

We get away with that at the moment because we also use the DOTSYM
macro, and that is also incorrectly prepending a '.' in 32-bit VDSO
code due to a separate bug.

But we shouldn't be generating function descriptors for this file,
there's no 32-bit ABI that includes function descriptors, so the
resulting object file is some frankenstein and it's surprising that it
even links.

So filter out all the ABI-related options we add to CFLAGS for 64-bit
builds, so that they're not used when building 32-bit code. With that
we only see regular text symbols:

  $ nm arch/powerpc/kernel/vdso32/vgettimeofday.o                                                                                                                                     michael@alpine1-p1
  000005d0 T __c_kernel_clock_getres
  00000000 T __c_kernel_clock_gettime
  00000200 T __c_kernel_clock_gettime64
  00000410 T __c_kernel_gettimeofday
  00000650 T __c_kernel_time

Fixes: ab037dd87a ("powerpc/vdso: Switch VDSO to generic C implementation.")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201218111619.1206391-2-mpe@ellerman.id.au
2020-12-21 22:06:26 +11:00
Michael Ellerman
42ed6d56ad powerpc/vdso: Block R_PPC_REL24 relocations
Add R_PPC_REL24 relocations to the list of relocations we do NOT
support in the VDSO.

These are generated in some cases and we do not support relocating
them at runtime, so if they appear then the VDSO will not work at
runtime, therefore it's preferable to break the build if we see them.

Fixes: ab037dd87a ("powerpc/vdso: Switch VDSO to generic C implementation.")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201218111619.1206391-1-mpe@ellerman.id.au
2020-12-21 22:06:25 +11:00
Cédric Le Goater
9014eab6a3 powerpc/smp: Add __init to init_big_cores()
It fixes this link warning:

WARNING: modpost: vmlinux.o(.text.unlikely+0x2d98): Section mismatch in reference from the function init_big_cores.isra.0() to the function .init.text:init_thread_group_cache_map()
The function init_big_cores.isra.0() references
the function __init init_thread_group_cache_map().
This is often because init_big_cores.isra.0 lacks a __init
annotation or the annotation of init_thread_group_cache_map is wrong.

Fixes: 425752c63b ("powerpc: Detect the presence of big-cores via "ibm, thread-groups"")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201221074154.403779-1-clg@kaod.org
2020-12-21 22:06:10 +11:00
Christophe Leroy
0faa22f09c powerpc/time: Force inlining of get_tb()
Force inlining of get_tb() in order to avoid getting
following function in vdso32, leading to suboptimal
performance in clock_gettime()

00000688 <.get_tb>:
 688:	7c 6d 42 a6 	mftbu   r3
 68c:	7c 8c 42 a6 	mftb    r4
 690:	7d 2d 42 a6 	mftbu   r9
 694:	7c 03 48 40 	cmplw   r3,r9
 698:	40 e2 ff f0 	bne+    688 <.get_tb>
 69c:	4e 80 00 20 	blr

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/df05d53eed1210cf1aa76d1fb44aa0fab29c018e.1608488286.git.christophe.leroy@csgroup.eu
2020-12-21 22:06:10 +11:00
Michael Ellerman
b36f835b63 powerpc/boot: Fix build of dts/fsl
The lkp robot reported that some configs fail to build, for example
mpc85xx_smp_defconfig, with:

  cc1: fatal error: opening output file arch/powerpc/boot/dts/fsl/.mpc8540ads.dtb.dts.tmp: No such file or directory

This bisects to:
  cc8a51ca6f ("kbuild: always create directories of targets")

Although that commit claims to be about in-tree builds, it somehow
breaks out-of-tree builds. But presumably it's just exposing a latent
bug in our Makefiles.

We can fix it by adding to targets for dts/fsl in the same way that we
do for dts.

Fixes: cc8a51ca6f ("kbuild: always create directories of targets")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20201215032906.473460-1-mpe@ellerman.id.au
2020-12-21 22:06:09 +11:00
Rafael J. Wysocki
e40ad84c26 cpufreq: intel_pstate: Use most recent guaranteed performance values
When turbo has been disabled by the BIOS, but HWP_CAP.GUARANTEED is
changed later, user space may want to take advantage of this increased
guaranteed performance.

HWP_CAP.GUARANTEED is not a static value.  It can be adjusted by an
out-of-band agent or during an Intel Speed Select performance level
change.  The HWP_CAP.MAX is still the maximum achievable performance
with turbo disabled by the BIOS, so HWP_CAP.GUARANTEED can still
change as long as it remains less than or equal to HWP_CAP.MAX.

When HWP_CAP.GUARANTEED is changed, the sysfs base_frequency
attribute shows the most recent guaranteed frequency value. This
attribute can be used by user space software to update the scaling
min/max limits of the CPU.

Currently, the ->setpolicy() callback already uses the latest
HWP_CAP values when setting HWP_REQ, but the ->verify() callback will
restrict the user settings to the to old guaranteed performance value
which prevents user space from making use of the extra CPU capacity
theoretically available to it after increasing HWP_CAP.GUARANTEED.

To address this, read HWP_CAP in intel_pstate_verify_cpu_policy()
to obtain the maximum P-state that can be used and use that to
confine the policy max limit instead of using the cached and
possibly stale pstate.max_freq value for this purpose.

For consistency, update intel_pstate_update_perf_limits() to use the
maximum available P-state returned by intel_pstate_get_hwp_max() to
compute the maximum frequency instead of using the return value of
intel_pstate_get_max_freq() which, again, may be stale.

This issue is a side-effect of fixing the scaling frequency limits in
commit eacc9c5a92 ("cpufreq: intel_pstate: Fix intel_pstate_get_hwp_max()
for turbo disabled") which corrected the setting of the reduced scaling
frequency values, but caused stale HWP_CAP.GUARANTEED to be used in
the case at hand.

Fixes: eacc9c5a92 ("cpufreq: intel_pstate: Fix intel_pstate_get_hwp_max() for turbo disabled")
Reported-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Tested-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: 5.8+ <stable@vger.kernel.org> # 5.8+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-12-21 10:51:00 +01:00
Takashi Iwai
525d9c57d0 ALSA: usb-audio: Add alias entry for ASUS PRIME TRX40 PRO-S
ASUS PRIME TRX40 PRO-S mobo with 0b05:1918 needs the same quirk alias
for another ASUS mobo (0b05:1917) for the proper mixer mapping, etc.
Add the corresponding entry.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=210783
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201221080159.24468-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-12-21 09:02:33 +01:00
YangHui
8b7c764e06 ALSA: core: Remove redundant comments
Remove redundant comments

Signed-off-by: YangHui <yanghui.def@gmail.com>
Link: https://lore.kernel.org/r/1608531727-5433-1-git-send-email-yanghui.def@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-12-21 08:55:15 +01:00
Masahiro Yamada
90d39628ac kconfig: doc: fix $(fileno) to $(filename)
This is a typo.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 16:01:44 +09:00
Masahiro Yamada
135b4957ea kconfig: fix return value of do_error_if()
$(error-if,...) is expanded to an empty string. Currently, it relies on
eval_clause() returning xstrdup("") when all attempts for expansion fail,
but the correct implementation is to make do_error_if() return xstrdup("").

Fixes: 1d6272e6fe ("kconfig: add 'info', 'warning-if', and 'error-if' built-in functions")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 14:48:54 +09:00
Geert Uytterhoeven
18084e435f Documentation/kbuild: Document platform dependency practises
Document best practises for using architecture and platform dependencies.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Geert Uytterhoeven
c613583b6a Documentation/kbuild: Document COMPILE_TEST dependencies
Document best practises for using COMPILE_TEST dependencies.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Marco Elver
9ab55d7f24 genksyms: Ignore module scoped _Static_assert()
The C11 _Static_assert() keyword may be used at module scope, and we
need to teach genksyms about it to not abort with an error. We currently
have a growing number of static_assert() (but also direct usage of
_Static_assert()) users at module scope:

	git grep -E '^_Static_assert\(|^static_assert\(' | grep -v '^tools' | wc -l
	135

More recently, when enabling CONFIG_MODVERSIONS with CONFIG_KCSAN, we
observe a number of warnings:

	WARNING: modpost: EXPORT symbol "<..all kcsan symbols..>" [vmlinux] [...]

When running a preprocessed source through 'genksyms -w' a number of
syntax errors point at usage of static_assert()s. In the case of
kernel/kcsan/encoding.h, new static_assert()s had been introduced which
used expressions that appear to cause genksyms to not even be able to
recover from the syntax error gracefully (as it appears was the case
previously).

Therefore, make genksyms ignore all _Static_assert() and the contained
expression. With the fix, usage of _Static_assert() no longer cause
"syntax error" all over the kernel, and the above modpost warnings for
KCSAN are gone, too.

Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Quentin Perret
b9ed847b5a modpost: turn static exports into error
Using EXPORT_SYMBOL*() on static functions is fundamentally wrong.
Modpost currently reports that as a warning, but clearly this is not a
pattern we should allow, and all in-tree occurences should have been
fixed by now. So, promote the warn() message to error() to make sure
this never happens again.

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Masahiro Yamada
c7299d98c0 modpost: turn section mismatches to error from fatal()
There is code that reports static EXPORT_SYMBOL a few lines below.
It is not a good idea to bail out here.

I renamed sec_mismatch_fatal to sec_mismatch_warn_only (with logical
inversion) to match to CONFIG_SECTION_MISMATCH_WARN_ONLY.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Masahiro Yamada
d6d692fa21 modpost: change license incompatibility to error() from fatal()
Change fatal() to error() to continue running to report more possible
issues.

There is no difference in the fact that modpost will fail anyway.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Masahiro Yamada
1d6cd39293 modpost: turn missing MODULE_LICENSE() into error
Do not create modules with no license tag.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Masahiro Yamada
0fd3fbadd9 modpost: refactor error handling and clarify error/fatal difference
We have 3 log functions. fatal() is special because it lets modpost bail
out immediately. The difference between warn() and error() is the only
prefix parts ("WARNING:" vs "ERROR:").

In my understanding, the expected handling of error() is to propagate
the return code of the function to the exit code of modpost, as
check_exports() etc. already does. This is a good manner in general
because we should display as many error messages as possible in a
single run of modpost.

What is annoying about fatal() is that it kills modpost at the first
error. People would need to run Kbuild again and again until they fix
all errors.

But, unfortunately, people tend to do:
"This case should not be allowed. Let's replace warn() with fatal()."

One of the reasons is probably it is tedious to manually hoist the error
code to the main() function.

This commit refactors error() so any single call for it automatically
makes modpost return the error code.

I also added comments in modpost.h for warn(), error(), and fatal().

Please use fatal() only when you have a strong reason to do so.
For example:

  - Memory shortage (i.e. malloc() etc. has failed)
  - The ELF file is broken, and there is no point to continue parsing
  - Something really odd has happened

For general coding errors, please use error().

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Tested-by: Quentin Perret <qperret@google.com>
2020-12-21 13:57:08 +09:00
Masahiro Yamada
bc72d723ec modpost: rename merror() to error()
The log function names, warn(), merror(), fatal() are inconsistent.

Commit 2a11665945 ("kbuild: distinguish between errors and warnings
in modpost") intentionally chose merror() to avoid the conflict with
the library function error(). See man page of error(3).

But, we are already causing the conflict with warn() because it is also
a library function. See man page of warn(3). err() would be a problem
for the same reason.

The common technique to work around name conflicts is to use macros.
For example:

    /* in a header */
    #define error(fmt, ...)  __error(fmt, ##__VA_ARGS__)
    #define warn(fmt, ...)   __warn(fmt, ##__VA_ARGS__)

    /* function definition */
    void __error(const char *fmt, ...)
    {
            <our implementation>
    }

    void __warn(const char *fmt, ...)
    {
            <our implementation>
    }

In this way, we can implement our own warn() and error(), still we can
include <error.h> and <err.h> with no problem.

And, commit 93c95e526a ("modpost: rework and consolidate logging
interface") already did that.

Since the log functions are all macros, we can use error() without
causing "conflicting types" errors.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Dominique Martinet
436e980e2e kbuild: don't hardcode depmod path
depmod is not guaranteed to be in /sbin, just let make look for
it in the path like all the other invoked programs

Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:08 +09:00
Masahiro Yamada
c0ea806f87 kbuild: doc: document subdir-y syntax
There is no explanation about subdir-y.

Let's document it.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2020-12-21 13:57:07 +09:00
Masahiro Yamada
d0e628cd81 kbuild: doc: clarify the difference between extra-y and always-y
The difference between extra-y and always-y is obscure.

Basically, Kbuild builds targets listed in extra-y and always-y in
visited Makefiles without relying on any dependency.

The difference is that extra-y is used to list the targets needed for
vmlinux whereas always-y is used to list the targets that must be always
built irrespective of final targets.

Kbuild skips extra-y when it is building only modules (i.e.
'make modules'). This is the long-standing behavior since extra-y was
introduced in 2003, and it is explained in that commit log [1].

For clarification, this is the extra-y vs always-y table:

                  extra-y    always-y
  'make'             y          y
  'make vmlinux'     y          y
  'make modules'     n          y

Kbuild skips extra-y also when building external modules since obviously
it never builds vmlinux.

Unfortunately, extra-y is wrongly used in many places of upstream code,
and even in external modules.

Using extra-y in external module Makefiles is wrong. What you should
use is probably always-y or 'targets'.

The current documentation for extra-y is misleading. I rewrote it, and
moved it to the section 3.7.

always-y is not documented anywhere. I added.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/commit/?id=f94e5fd7e5d09a56a60670a9bb211a791654bba8

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2020-12-21 13:57:07 +09:00
Masahiro Yamada
39bb232ae6 kbuild: doc: split if_changed explanation to a separate section
The if_changed macro is currently explained in the section
"Commands useful for building a boot image", but the use of
if_changed is not limited to the boot image.

It is often used together with custom rules. Let's split it as a
separate section, and insert it after the "Custom Rules" section.

I slightly reworded the explanation, re-numbered to fill the <deleted>
section, and also fixed the broken indentation of the Note: part.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:07 +09:00
Masahiro Yamada
41cac0834f kbuild: doc: merge 'Special Rules' and 'Custom kbuild commands' sections
The two sections "3.10 Special Rules" and "7.8 Custom kbuild commands"
are related because you must understand both of them when you write
custom rules.

Actually I do not understand the policy about what to go into
"3 The kbuild files" and what into "7 Architecture Makefile".

This commit reworks the custom rule explanation as follows:

 - Merged "7.8 Custom kbuild commands" into "3.10 Special Rules".

 - Reword "Special Rules" to "Custom Rules" for consistency.

 - Update the example for kecho because the blackfin Makefile
   does not exist any more.

 - Replace the example for cmd_<command> with a simpler one.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:07 +09:00
Masahiro Yamada
23b53061ad kbuild: doc: fix 'List directories to visit when descending' section
Fix stale information:

 - Fix the section number in the reference from 6.4 to 7.4.

 - Remove init-y and net-y. They were removed by commit 23febe375d
   ("kbuild: merge init-y into core-y") and commit 95fb6317b3
   ("kbuild: merge net-y and virt-y into drivers-y"), respectively.

 - Update the example because arch/sparc64/Makefile does not exit.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:57:07 +09:00
Masahiro Yamada
8c4d9b145b kbuild: doc: replace arch/$(ARCH)/ with arch/$(SRCARCH)/
Precisely speaking, the arch directory is specified by $(SRCARCH),
not $(ARCH).

In old days, $(ARCH) actually matched to the arch directory because
32-bit and 64-bit were supported as separate architectures.

Most architectures (except arm/arm64) were unified like follows:

    arch/i386, arch/x86_64    ->  arch/x86
    arch/sh, arch/sh64        ->  arch/sh
    arch/sparc, arch/sparc64  ->  arch/sparc

To not break the user interface, commit 6752ed90da ("Kbuild: allow
arch/xxx to use a different source path") introduced SRCARCH to point
to the arch directory, still allowing to pass in the former ARCH=i386
or ARCH=x86_64.

Update the documents for preciseness, and add the explanation of SRCARCH.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
2020-12-21 13:56:58 +09:00
Masahiro Yamada
b044a535d9 kbuild: doc: update the description about kbuild Makefiles
This line was written in 2003. Now we have much more Makefiles.

The number of Makefiles is not important. The point is we have a
Makefile in (almost) every directory.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-12-21 13:55:29 +09:00