[ Upstream commit 31f48f16264bc70962fb3e7ec62da64d0a2ba04a ]

When clang's -Qunused-arguments is dropped from KBUILD_CPPFLAGS, it
points out that KBUILD_AFLAGS contains a linker flag, which will be
unused:

  clang: error: -Wl,-a32: 'linker' input unused [-Werror,-Wunused-command-line-argument]

This was likely supposed to be '-Wa,-a$(BITS)'. However, this change is
unnecessary, as all supported versions of clang and gcc will pass '-a64'
or '-a32' to GNU as based on the value of '-m'; the behavior of the
latest stable release of the oldest supported major version of each
compiler is shown below and each compiler's latest release exhibits the
same behavior (GCC 12.2.0 and Clang 15.0.6).

  $ powerpc64-linux-gcc --version | head -1
  powerpc64-linux-gcc (GCC) 5.5.0

  $ powerpc64-linux-gcc -m64 -### -x assembler-with-cpp -c -o /dev/null /dev/null &| grep 'as '
  .../as -a64 -mppc64 -many -mbig -o /dev/null /tmp/cctwuBzZ.s

  $ powerpc64-linux-gcc -m32 -### -x assembler-with-cpp -c -o /dev/null /dev/null &| grep 'as '
  .../as -a32 -mppc -many -mbig -o /dev/null /tmp/ccaZP4mF.sg

  $ clang --version | head -1
  Ubuntu clang version 11.1.0-++20211011094159+1fdec59bffc1-1~exp1~20211011214622.5

  $ clang --target=powerpc64-linux-gnu -fno-integrated-as -m64 -### \
    -x assembler-with-cpp -c -o /dev/null /dev/null &| grep gnu-as
   "/usr/bin/powerpc64-linux-gnu-as" "-a64" "-mppc64" "-many" "-o" "/dev/null" "/tmp/null-80267c.s"

  $ clang --target=powerpc64-linux-gnu -fno-integrated-as -m64 -### \
    -x assembler-with-cpp -c -o /dev/null /dev/null &| grep gnu-as
   "/usr/bin/powerpc64-linux-gnu-as" "-a32" "-mppc" "-many" "-o" "/dev/null" "/tmp/null-ab8f8d.s"

Remove this flag altogether to avoid future issues.

Fixes: 1421dc6d4829 ("powerpc/kbuild: Use flags variables rather than overriding LD/CC/AS")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Linux Kernel Functional Testing <lkft@linaro.org>
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

commit d78c8e32890ef7eca79ffd67c96022c7f9d8cce4 upstream.

Clang warns:

  arch/powerpc/mm/book3s64/radix_tlb.c:1191:23: error: variable 'hstart' is uninitialized when used here
    __tlbiel_va_range(hstart, hend, pid,
                      ^~~~~~
  arch/powerpc/mm/book3s64/radix_tlb.c:1191:31: error: variable 'hend' is uninitialized when used here
    __tlbiel_va_range(hstart, hend, pid,
                              ^~~~

Rework the 'if (IS_ENABLE(CONFIG_TRANSPARENT_HUGEPAGE))' so hstart/hend
is always initialized to silence the warnings. That will also simplify
the 'else' path. Clang is getting confused with these warnings, but the
warnings is a false-positive.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220810114318.3220630-1-anders.roxell@linaro.org
Signed-off-by: Daniel Díaz <daniel.diaz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull powerpc fix from Michael Ellerman:

 - Prevent fallthrough to hash TLB flush when using radix

Thanks to Benjamin Gray and Erhard Furtner.

* tag 'powerpc-6.2-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Prevent fallthrough to hash TLB flush when using radix

In the fix reconnecting hash__tlb_flush() to tlb_flush() the
void return on radix__tlb_flush() was not restored and subsequently
falls through to the restored hash__tlb_flush().

Guard hash__tlb_flush() under an else to prevent this.

Fixes: 1665c027afb2 ("powerpc/64s: Reconnect tlb_flush() to hash__tlb_flush()")
Reported-by: "Erhard F." <erhard_f@mailbox.org>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Benjamin Gray <bgray@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230217011434.115554-1-bgray@linux.ibm.com

Pull powerpc fixes from Michael Ellerman:

 - Fix interrupt exit race with security mitigation switching.

 - Don't select ARCH_WANTS_NO_INSTR until warnings are fixed.

 - Build fix for CONFIG_NUMA=n.

Thanks to Nicholas Piggin, Randy Dunlap, and Sachin Sant.

* tag 'powerpc-6.2-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s/interrupt: Fix interrupt exit race with security mitigation switch
  powerpc/kexec_file: fix implicit decl error
  powerpc: Don't select ARCH_WANTS_NO_INSTR

The RFI and STF security mitigation options can flip the
interrupt_exit_not_reentrant static branch condition concurrently with
the interrupt exit code which tests that branch.

Interrupt exit tests this condition to set MSR[EE|RI] for exit, then
again in the case a soft-masked interrupt is found pending, to recover
the MSR so the interrupt can be replayed before attempting to exit
again. If the condition changes between these two tests, the MSR and irq
soft-mask state will become corrupted, leading to warnings and possible
crashes. For example, if the branch is initially true then false,
MSR[EE] will be 0 but PACA_IRQ_HARD_DIS clear and EE may not get
enabled, leading to warnings in irq_64.c.

Fixes: 13799748b957 ("powerpc/64: use interrupt restart table to speed up return from interrupt")
Cc: stable@vger.kernel.org # v5.14+
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230206042240.92103-1-npiggin@gmail.com

kexec (PPC64) code calls memory_hotplug_max(). Add the header
declaration for it from <asm/mmzone.h>. Using <linux/mmzone.h> does not
work since the #include for <asm/mmzone.h> depends on CONFIG_NUMA=y,
which is not always set.

Fixes this build error/warning:

  arch/powerpc/kexec/file_load_64.c: In function 'kexec_extra_fdt_size_ppc64':
  arch/powerpc/kexec/file_load_64.c:993:33: error: implicit declaration of function 'memory_hotplug_max'
  993 |                 usm_entries = ((memory_hotplug_max() / drmem_lmb_size()) +
      |                                 ^~~~~~~~~~~~~~~~~~

Fixes: fc546faa5595 ("powerpc/kexec_file: Count hot-pluggable memory in FDT estimate")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230204172206.7662-1-rdunlap@infradead.org

Pull powerpc fixes from Michael Ellerman:
 "It's a bit of a big batch for rc6, but just because I didn't send any
  fixes the last week or two while I was on vacation, next week should
  be quieter:

   - Fix a few objtool warnings since we recently enabled objtool.

   - Fix a deadlock with the hash MMU vs perf record.

   - Fix perf profiling of asynchronous interrupt handlers.

   - Revert the IMC PMU nest_init_lock to being a mutex.

   - Two commits fixing problems with the kexec_file FDT size
     estimation.

   - Two commits fixing problems with strict RWX vs kernels running at
     non-zero.

   - Reconnect tlb_flush() to hash__tlb_flush()

  Thanks to Kajol Jain, Nicholas Piggin, Sachin Sant Sathvika Vasireddy,
  and Sourabh Jain"

* tag 'powerpc-6.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/64s: Reconnect tlb_flush() to hash__tlb_flush()
  powerpc/kexec_file: Count hot-pluggable memory in FDT estimate
  powerpc/64s/radix: Fix RWX mapping with relocated kernel
  powerpc/64s/radix: Fix crash with unaligned relocated kernel
  powerpc/kexec_file: Fix division by zero in extra size estimation
  powerpc/imc-pmu: Revert nest_init_lock to being a mutex
  powerpc/64: Fix perf profiling asynchronous interrupt handlers
  powerpc/64s: Fix local irq disable when PMIs are disabled
  powerpc/kvm: Fix unannotated intra-function call warning
  powerpc/85xx: Fix unannotated intra-function call warning

Commit 41b7a347bf14 ("powerpc: Book3S 64-bit outline-only KASAN
support") added a select of ARCH_WANTS_NO_INSTR, because it also added
some uses of noinstr. However noinstr is always defined, regardless of
ARCH_WANTS_NO_INSTR, so there's no need to select it just for that.

As PeterZ says [1]:
  Note that by selecting ARCH_WANTS_NO_INSTR you effectively state to
  abide by its rules.

As of now the powerpc code does not abide by those rules, and trips some
new warnings added by Peter in linux-next.

So until the code can be fixed to avoid those warnings, disable
ARCH_WANTS_NO_INSTR.

Note that ARCH_WANTS_NO_INSTR is also used to gate building KCOV and
parts of KCSAN. However none of the noinstr annotations in powerpc were
added for KCOV or KCSAN, instead instrumentation is blocked at the file
level using KCOV_INSTRUMENT_foo.o := n.

[1]: https://lore.kernel.org/linuxppc-dev/Y9t6yoafrO5YqVgM@hirez.programming.kicks-ass.net

Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Commit baf1ed24b27d ("powerpc/mm: Remove empty hash__ functions")
removed some empty hash MMU flushing routines, but got a bit overeager
and also removed the call to hash__tlb_flush() from tlb_flush().

In regular use this doesn't lead to any noticable breakage, which is a
little concerning. Presumably there are flushes happening via other
paths such as arch_leave_lazy_mmu_mode(), and/or a bit of luck.

Fix it by reinstating the call to hash__tlb_flush().

Fixes: baf1ed24b27d ("powerpc/mm: Remove empty hash__ functions")
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230131111407.806770-1-mpe@ellerman.id.au