linux-stable.git/arch/mips, branch v5.18.2

mips: use fallback for random_get_entropy() instead of just c0 random

2022-05-30T07:24:05+00:00

commit 1c99c6a7c3c599a68321b01b9ec243215ede5a68 upstream.

For situations in which we don't have a c0 counter register available,
we've been falling back to reading the c0 "random" register, which is
usually bounded by the amount of TLB entries and changes every other
cycle or so. This means it wraps extremely often. We can do better by
combining this fast-changing counter with a potentially slower-changing
counter from random_get_entropy_fallback() in the more significant bits.
This commit combines the two, taking into account that the changing bits
are in a different bit position depending on the CPU model. In addition,
we previously were falling back to 0 for ancient CPUs that Linux does
not support anyway; remove that dead path entirely.

Cc: Thomas Gleixner 
Cc: Arnd Bergmann 
Tested-by: Maciej W. Rozycki 
Acked-by: Thomas Bogendoerfer 
Signed-off-by: Jason A. Donenfeld 
Signed-off-by: Greg Kroah-Hartman

MIPS: Fix CP0 counter erratum detection for R4k CPUs

2022-04-29T13:52:00+00:00

Fix the discrepancy between the two places we check for the CP0 counter
erratum in along with the incorrect comparison of the R4400 revision
number against 0x30 which matches none and consistently consider all
R4000 and R4400 processors affected, as documented in processor errata
publications[1][2][3], following the mapping between CP0 PRId register
values and processor models:

  PRId   |  Processor Model
---------+--------------------
00000422 | R4000 Revision 2.2
00000430 | R4000 Revision 3.0
00000440 | R4400 Revision 1.0
00000450 | R4400 Revision 2.0
00000460 | R4400 Revision 3.0

No other revision of either processor has ever been spotted.

Contrary to what has been stated in commit ce202cbb9e0b ("[MIPS] Assume
R4000/R4400 newer than 3.0 don't have the mfc0 count bug") marking the
CP0 counter as buggy does not preclude it from being used as either a
clock event or a clock source device.  It just cannot be used as both at
a time, because in that case clock event interrupts will be occasionally
lost, and the use as a clock event device takes precedence.

Compare against 0x4ff in `can_use_mips_counter' so that a single machine
instruction is produced.

References:

[1] "MIPS R4000PC/SC Errata, Processor Revision 2.2 and 3.0", MIPS
    Technologies Inc., May 10, 1994, Erratum 53, p.13

[2] "MIPS R4400PC/SC Errata, Processor Revision 1.0", MIPS Technologies
    Inc., February 9, 1994, Erratum 21, p.4

[3] "MIPS R4400PC/SC Errata, Processor Revision 2.0 & 3.0", MIPS
    Technologies Inc., January 24, 1995, Erratum 14, p.3

Signed-off-by: Maciej W. Rozycki 
Fixes: ce202cbb9e0b ("[MIPS] Assume R4000/R4400 newer than 3.0 don't have the mfc0 count bug")
Cc: stable@vger.kernel.org # v2.6.24+
Reviewed-by: Philippe Mathieu-Daudé 
Signed-off-by: Thomas Bogendoerfer

Merge tag 'mips_5.18_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux

2022-04-02T19:14:38+00:00

Pull MIPS fixes from Thomas Bogendoerfer:

 - build fix for gpio

 - fix crc32 build problems

 - check for failed memory allocations

* tag 'mips_5.18_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: crypto: Fix CRC32 code
  MIPS: rb532: move GPIOD definition into C-files
  MIPS: lantiq: check the return value of kzalloc()
  mips: sgi-ip22: add a check for the return of kzalloc()

MIPS: crypto: Fix CRC32 code

2022-04-01T08:19:03+00:00

Commit 67512a8cf5a7 ("MIPS: Avoid macro redefinitions") changed how the
MIPS register macros were defined, in order to allow the code to compile
under LLVM/Clang.

The MIPS CRC32 code however wasn't updated accordingly, causing a build
bug when using a MIPS32r6 toolchain without CRC support.

Update the CRC32 code to use the macros correctly, to fix the build
failures.

Fixes: 67512a8cf5a7 ("MIPS: Avoid macro redefinitions")
Cc: 
Signed-off-by: Paul Cercueil 
Reported-by: kernel test robot 
Signed-off-by: Thomas Bogendoerfer

Merge tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

2022-03-31T18:59:03+00:00

Pull Kbuild updates from Masahiro Yamada:

 - Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
   additional flags to be passed to user-space programs.

 - Fix missing fflush() bugs in Kconfig and fixdep

 - Fix a minor bug in the comment format of the .config file

 - Make kallsyms ignore llvm's local labels, .L*

 - Fix UAPI compile-test for cross-compiling with Clang

 - Extend the LLVM= syntax to support LLVM= form for using a
   particular version of LLVm, and LLVM= form for using custom
   LLVM in a particular directory path.

 - Clean up Makefiles

* tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: Make $(LLVM) more flexible
  kbuild: add --target to correctly cross-compile UAPI headers with Clang
  fixdep: use fflush() and ferror() to ensure successful write to files
  arch: syscalls: simplify uapi/kapi directory creation
  usr/include: replace extra-y with always-y
  certs: simplify empty certs creation in certs/Makefile
  certs: include certs/signing_key.x509 unconditionally
  kallsyms: ignore all local labels prefixed by '.L'
  kconfig: fix missing '# end of' for empty menu
  kconfig: add fflush() before ferror() check
  kbuild: replace $(if A,A,B) with $(or A,B)
  kbuild: Add environment variables for userprogs flags
  kbuild: unify cmd_copy and cmd_shipped

arch: syscalls: simplify uapi/kapi directory creation

2022-03-31T03:03:46+00:00

$(shell ...) expands to empty. There is no need to assign it to _dummy.

Signed-off-by: Masahiro Yamada 
Acked-by: Geert Uytterhoeven

MIPS: rb532: move GPIOD definition into C-files

2022-03-30T18:26:26+00:00

My kernel robot reports build error from drivers/iio/adc/da9150-gpadc.c,

  drivers/iio/adc/da9150-gpadc.c:254:13: error: ‘DA9150_GPADC_CHAN_0x08’
  undeclared here (not in a function); did you mean ‘DA9150_GPADC_CHAN_TBAT’?
     254 |  .channel = DA9150_GPADC_CHAN_##_id,

We define GPIOD in rb.h, in fact it should only be used in gpio.c, but
it affects the driver da9150-gpadc.c which goes against the original
intention of the design, just move it to its scope.

Fixes: 1b432840d0a4 ("MIPS: RB532: GPIO register offsets are relative to GPIOBASE")
Suggested-by: Jonathan Cameron 
Suggested-by: Andy Shevchenko 
Reported-by: k2ci 
Signed-off-by: Jackie Liu 
Signed-off-by: Thomas Bogendoerfer

MIPS: lantiq: check the return value of kzalloc()

2022-03-30T18:25:48+00:00

kzalloc() is a memory allocation function which can return NULL when
some internal memory errors happen. So it is better to check the
return value of it to prevent potential wrong memory access or
memory leak.

Signed-off-by: Xiaoke Wang 
Signed-off-by: Thomas Bogendoerfer

mips: sgi-ip22: add a check for the return of kzalloc()

2022-03-30T18:25:11+00:00

kzalloc() is a memory allocation function which can return NULL when
some internal memory errors happen. So it is better to check it to
prevent potential wrong memory access.

Signed-off-by: Xiaoke Wang 
Signed-off-by: Thomas Bogendoerfer

Merge tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

2022-03-29T00:29:53+00:00

Pull ptrace cleanups from Eric Biederman:
 "This set of changes removes tracehook.h, moves modification of all of
  the ptrace fields inside of siglock to remove races, adds a missing
  permission check to ptrace.c

  The removal of tracehook.h is quite significant as it has been a major
  source of confusion in recent years. Much of that confusion was around
  task_work and TIF_NOTIFY_SIGNAL (which I have now decoupled making the
  semantics clearer).

  For people who don't know tracehook.h is a vestiage of an attempt to
  implement uprobes like functionality that was never fully merged, and
  was later superseeded by uprobes when uprobes was merged. For many
  years now we have been removing what tracehook functionaly a little
  bit at a time. To the point where anything left in tracehook.h was
  some weird strange thing that was difficult to understand"

* tag 'ptrace-cleanups-for-v5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  ptrace: Remove duplicated include in ptrace.c
  ptrace: Check PTRACE_O_SUSPEND_SECCOMP permission on PTRACE_SEIZE
  ptrace: Return the signal to continue with from ptrace_stop
  ptrace: Move setting/clearing ptrace_message into ptrace_stop
  tracehook: Remove tracehook.h
  resume_user_mode: Move to resume_user_mode.h
  resume_user_mode: Remove #ifdef TIF_NOTIFY_RESUME in set_notify_resume
  signal: Move set_notify_signal and clear_notify_signal into sched/signal.h
  task_work: Decouple TIF_NOTIFY_SIGNAL and task_work
  task_work: Call tracehook_notify_signal from get_signal on all architectures
  task_work: Introduce task_work_pending
  task_work: Remove unnecessary include from posix_timers.h
  ptrace: Remove tracehook_signal_handler
  ptrace: Remove arch_syscall_{enter,exit}_tracehook
  ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h
  ptrace/arm: Rename tracehook_report_syscall report_syscall
  ptrace: Move ptrace_report_syscall into ptrace.h