When taking an SError or Debug exception from EL0, we run the C
handler for these exceptions before updating the context tracking
code and unmasking lower priority interrupts.

When booting with nohz_full lockdep tells us we got this wrong:
| =============================
| WARNING: suspicious RCU usage
| 5.3.0-rc2-00010-gb4b5e9dcb11b-dirty #11271 Not tainted
| -----------------------------
| include/linux/rcupdate.h:643 rcu_read_unlock() used illegally wh!
|
| other info that might help us debug this:
|
|
| RCU used illegally from idle CPU!
| rcu_scheduler_active = 2, debug_locks = 1
| RCU used illegally from extended quiescent state!
| 1 lock held by a.out/432:
|  #0: 00000000c7a79515 (rcu_read_lock){....}, at: brk_handler+0x00
|
| stack backtrace:
| CPU: 1 PID: 432 Comm: a.out Not tainted 5.3.0-rc2-00010-gb4b5e9d1
| Hardware name: ARM LTD ARM Juno Development Platform/ARM Juno De8
| Call trace:
|  dump_backtrace+0x0/0x140
|  show_stack+0x14/0x20
|  dump_stack+0xbc/0x104
|  lockdep_rcu_suspicious+0xf8/0x108
|  brk_handler+0x164/0x1b0
|  do_debug_exception+0x11c/0x278
|  el0_dbg+0x14/0x20

Moving the ct_user_exit calls to be before do_debug_exception() means
they are also before trace_hardirqs_off() has been updated. Add a new
ct_user_exit_irqoff macro to avoid the context-tracking code using
irqsave/restore before we've updated trace_hardirqs_off(). To be
consistent, do this everywhere.

The C helper is called enter_from_user_mode() to match x86 in the hope
we can merge them into kernel/context_tracking.c later.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 6c81fe79 ("arm64: enable context tracking")
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

This reverts commit 71c67a31.

Commit 117acf5c ("powerpc/Makefile: Always pass --synthetic to nm if
supported") removed the only conditional definition of $(NM), so we can
revert our temporary bodge to avoid Kconfig recursion and go back to
passing $(NM) through to the 'tools-support-relr.sh' when detecting
support for RELR relocations.
Signed-off-by: Will Deacon <will@kernel.org>

Back in 2004 we added logic to arch/ppc64/Makefile to pass
the --synthetic option to nm, if it was supported by nm.

Then in 2005 when arch/ppc64 and arch/ppc were merged, the logic to
add --synthetic was moved inside an #ifdef CONFIG_PPC64 block within
arch/powerpc/Makefile, and has remained there since.

That was fine, though crufty, until recently when a change to
init/Kconfig added a config time check that uses $(NM). On powerpc
that leads to an infinite loop because Kconfig uses $(NM) to calculate
some values, then the powerpc Makefile changes $(NM), which Kconfig
notices and restarts.

The original commit that added --synthetic simply said:
  On new toolchains we need to use nm --synthetic or we miss code
  symbols.

And the nm man page says that the --synthetic option causes nm to:
  Include synthetic symbols in the output. These are special symbols
  created by the linker for various purposes.

So it seems safe to always pass --synthetic if nm supports it, ie. on
32-bit and 64-bit, it just means 32-bit kernels might have more
symbols reported (and in practice I see no extra symbols). Making it
unconditional avoids the #ifdef CONFIG_PPC64, which in turn avoids the
infinite loop.
Debugged-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Will Deacon <will@kernel.org>

No module currently messed with clearing or setting the execute
permission of kernel memory, and none really should.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Will Deacon <will@kernel.org>

It seems that LLVM's linker does not correctly handle variable assignments
involving section positions that are updated during the SECTIONS
parsing. Commit aa69fb62 ("arm64/efi: Mark __efistub_stext_offset as
an absolute symbol explicitly") ran into this too, but found a different
workaround.

However, this was not enough, as other variables were also miscalculated
which manifested as boot failures under UEFI where __efistub__end was
not taking the correct _end value (they should be the same):

$ ld.lld -EL -maarch64elf --no-undefined -X -shared \
	-Bsymbolic -z notext -z norelro --no-apply-dynamic-relocs \
	-o vmlinux.lld -T poc.lds --whole-archive vmlinux.o && \
  readelf -Ws vmlinux.lld | egrep '\b(__efistub_|)_end\b'
368272: ffff000002218000     0 NOTYPE  LOCAL  HIDDEN    38 __efistub__end
368322: ffff000012318000     0 NOTYPE  GLOBAL DEFAULT   38 _end

$ aarch64-linux-gnu-ld.bfd -EL -maarch64elf --no-undefined -X -shared \
	-Bsymbolic -z notext -z norelro --no-apply-dynamic-relocs \
	-o vmlinux.bfd -T poc.lds --whole-archive vmlinux.o && \
  readelf -Ws vmlinux.bfd | egrep '\b(__efistub_|)_end\b'
338124: ffff000012318000     0 NOTYPE  LOCAL  DEFAULT  ABS __efistub__end
383812: ffff000012318000     0 NOTYPE  GLOBAL DEFAULT 15325 _end

To work around this, all of the __efistub_-prefixed variable assignments
need to be moved after the linker script's SECTIONS entry. As it turns
out, this also solves the problem fixed in commit aa69fb62, so those
changes are reverted here.

Link: https://github.com/ClangBuiltLinux/linux/issues/634
Link: https://bugs.llvm.org/show_bug.cgi?id=42990Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will@kernel.org>

Strengthen the wording in the documentation for cpu_enable() to make it
more obvious to readers not already familiar with the code when the core
will call this callback and that this is intentional.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
[will: minor tweak to emphasis in the comment]
Signed-off-by: Will Deacon <will@kernel.org>

All instances of struct sys64_hook contain compile-time constant data,
and are never inentionally modified, so let's make them all const.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

The aarch64_insn_encoding_class[] array contains compile-time constant
data, and is never intentionally modified, so let's mark it as const.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

The icache_policy_str[] array contains compile-time constant data, and
is never intentionally modified, so let's mark it as const.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

GCC unescapes escaped string section names while Clang does not. Because
__section uses the `#` stringification operator for the section name, it
doesn't need to be escaped.

This antipattern was found with:
$ grep -e __section\(\" -e __section__\(\" -r
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Will Deacon <will@kernel.org>

The ptrace trace SVE flags are prefixed with SVE_PT_*. Update the
comment accordingly.
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

This change prints the hexadecimal EC value in mem_abort_decode(),
which makes it easier to lookup the corresponding EC in
the ARM Architecture Reference Manual.

The commit 1f9b8936 ("arm64: Decode information from ESR upon mem
faults") prints useful information when memory abort occurs. It would
be easier to lookup "0x25" instead of "DABT" in the document. Then we
can check the corresponding ISS.

For example:
Current	info	  	Document
		  	EC	Exception class
"CP15 MCR/MRC"		0x3	"MCR or MRC access to CP15a..."
"ASIMD"			0x7	"Access to SIMD or floating-point..."
"DABT (current EL)" 	0x25	"Data Abort taken without..."
...

Before:
Unable to handle kernel paging request at virtual address 000000000000c000
Mem abort info:
  ESR = 0x96000046
  Exception class = DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000046
  CM = 0, WnR = 1

After:
Unable to handle kernel paging request at virtual address 000000000000c000
Mem abort info:
  ESR = 0x96000046
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
Data abort info:
  ISV = 0, ISS = 0x00000046
  CM = 0, WnR = 1

Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: James Morse <james.morse@arm.com>
Acked-by: Mark Rutland <Mark.rutland@arm.com>
Signed-off-by: Miles Chen <miles.chen@mediatek.com>
Signed-off-by: Will Deacon <will@kernel.org>

The commit d5370f75 ("arm64: prefetch: add alternative pattern for
CPUs without a prefetcher") introduced MIDR_IS_CPU_MODEL_RANGE() to be
used in has_no_hw_prefetch() with rv_min=0 which generates a compilation
warning from GCC,

In file included from ./arch/arm64/include/asm/cache.h:8,
               from ./include/linux/cache.h:6,
               from ./include/linux/printk.h:9,
               from ./include/linux/kernel.h:15,
               from ./include/linux/cpumask.h:10,
               from arch/arm64/kernel/cpufeature.c:11:
arch/arm64/kernel/cpufeature.c: In function 'has_no_hw_prefetch':
./arch/arm64/include/asm/cputype.h:59:26: warning: comparison of
unsigned expression >= 0 is always true [-Wtype-limits]
_model == (model) && rv >= (rv_min) && rv <= (rv_max);  \
                        ^~
arch/arm64/kernel/cpufeature.c:889:9: note: in expansion of macro
'MIDR_IS_CPU_MODEL_RANGE'
return MIDR_IS_CPU_MODEL_RANGE(midr, MIDR_THUNDERX,
       ^~~~~~~~~~~~~~~~~~~~~~~

Fix it by converting MIDR_IS_CPU_MODEL_RANGE to a static inline
function.
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Will Deacon <will@kernel.org>

Commit 5cf896fb ("arm64: Add support for relocating the kernel with
RELR relocations") introduced CONFIG_TOOLS_SUPPORT_RELR, which checks
for RELR support in the toolchain as part of the kernel configuration.
During this procedure, "$(NM)" is invoked to see if it supports the new
relocation format, however PowerPC conditionally overrides this variable
in the architecture Makefile in order to pass '--synthetic' when
targetting PPC64.

This conditional override causes Kconfig to recurse forever, since
CONFIG_TOOLS_SUPPORT_RELR cannot be determined without $(NM) being
defined, but that in turn depends on CONFIG_PPC64:

  $ make ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
  scripts/kconfig/conf  --syncconfig Kconfig
  scripts/kconfig/conf  --syncconfig Kconfig
  scripts/kconfig/conf  --syncconfig Kconfig
  [...]

In this particular case, it looks like PowerPC may be able to pass
'--synthetic' unconditionally to nm or even drop it altogether. While
that is being resolved, let's just bodge the RELR check by picking up
$(NM) directly from the environment in whatever state it happens to be
in.

Cc: Peter Collingbourne <pcc@google.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will@kernel.org>

RELR is a relocation packing format for relative relocations.
The format is described in a generic-abi proposal:
https://groups.google.com/d/topic/generic-abi/bX460iggiKg/discussion

The LLD linker can be instructed to pack relocations in the RELR
format by passing the flag --pack-dyn-relocs=relr.

This patch adds a new config option, CONFIG_RELR. Enabling this option
instructs the linker to pack vmlinux's relative relocations in the RELR
format, and causes the kernel to apply the relocations at startup along
with the RELA relocations. RELA relocations still need to be applied
because the linker will emit RELA relative relocations if they are
unrepresentable in the RELR format (i.e. address not a multiple of 2).

Enabling CONFIG_RELR reduces the size of a defconfig kernel image
with CONFIG_RANDOMIZE_BASE by 3.5MB/16% uncompressed, or 550KB/5%
compressed (lz4).
Signed-off-by: Peter Collingbourne <pcc@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Will Deacon <will@kernel.org>

Some TIF_* flags are documented in the comment block at the top, some
next to their definitions, some in both places.

Move all documentation to the individual definitions for consistency,
and for easy lookup.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Will Deacon <will@kernel.org>

We should free the initrd reserved memblock in an aligned manner,
because the initrd reserves the memblock in an aligned manner
in arm64_memblock_init().
Otherwise there are some fragments in memblock_reserved regions
after free_initrd_mem(). e.g.:
/sys/kernel/debug/memblock # cat reserved
   0: 0x0000000080080000..0x00000000817fafff
   1: 0x0000000083400000..0x0000000083ffffff
   2: 0x0000000090000000..0x000000009000407f
   3: 0x00000000b0000000..0x00000000b000003f
   4: 0x00000000b26184ea..0x00000000b2618fff
The fragments like the ranges from b0000000 to b000003f and
from b26184ea to b2618fff should be freed.

And we can do free_reserved_area() after memblock_free(),
as free_reserved_area() calls __free_pages(), once we've done
that it could be allocated somewhere else,
but memblock and iomem still say this is reserved memory.

Fixes: 05c58752 ("arm64: To remove initrd reserved area entry from memblock")
Signed-off-by: Junhua Huang <huang.junhua@zte.com.cn>
Signed-off-by: Will Deacon <will@kernel.org>

The arm64 implementation of the default I/O accessors requires barrier
instructions to satisfy the memory ordering requirements documented in
memory-barriers.txt [1], which are largely derived from the behaviour of
I/O accesses on x86.

Of particular interest are the requirements that a write to a device
must be ordered against prior writes to memory, and a read from a device
must be ordered against subsequent reads from memory. We satisfy these
requirements using various flavours of DSB: the most expensive barrier
we have, since it implies completion of prior accesses. This was deemed
necessary when we first implemented the accessors, since accesses to
different endpoints could propagate independently and therefore the only
way to enforce order is to rely on completion guarantees [2].

Since then, the Armv8 memory model has been retrospectively strengthened
to require "other-multi-copy atomicity", a property that requires memory
accesses from an observer to become visible to all other observers
simultaneously [3]. In other words, propagation of accesses is limited
to transitioning from locally observed to globally observed. It recently
became apparent that this change also has a subtle impact on our I/O
accessors for shared peripherals, allowing us to use the cheaper DMB
instruction instead.

As a concrete example, consider the following:

	memcpy(dma_buffer, data, bufsz);
	writel(DMA_START, dev->ctrl_reg);

A DMB ST instruction between the final write to the DMA buffer and the
write to the control register will ensure that the writes to the DMA
buffer are observed before the write to the control register by all
observers. Put another way, if an observer can see the write to the
control register, it can also see the writes to memory. This has always
been the case and is not sufficient to provide the ordering required by
Linux, since there is no guarantee that the master interface of the
DMA-capable device has observed either of the accesses. However, in an
other-multi-copy atomic world, we can infer two things:

  1. A write arriving at an endpoint shared between multiple CPUs is
     visible to all CPUs

  2. A write that is visible to all CPUs is also visible to all other
     observers in the shareability domain

Pieced together, this allows us to use DMB OSHST for our default I/O
write accessors and DMB OSHLD for our default I/O read accessors (the
outer-shareability is for handling non-cacheable mappings) for shared
devices. Memory-mapped, DMA-capable peripherals that are private to a
CPU (i.e. inaccessible to other CPUs) still require the DSB, however
these are few and far between and typically require special treatment
anyway which is outside of the scope of the portable driver API (e.g.
GIC, page-table walker, SPE profiler).

Note that our mandatory barriers remain as DSBs, since there are cases
where they are used to flush the store buffer of the CPU, e.g. when
publishing page table updates to the SMMU.

[1] https://git.kernel.org/linus/4614bbdee357
[2] https://www.youtube.com/watch?v=i6DayghhA8Q
[3] https://www.cl.cam.ac.uk/~pes20/armv8-mca/Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

The function cpucap_multi_entry_cap_cpu_enable() is unused, remove it to
avoid any confusion reading the code and potential for bit rot.
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

Our SCTLR_ELx field definitions are somewhat over-engineered in that
they carefully define masks describing the RES0/RES1 bits and then use
these to construct further masks representing bits to be set/cleared for
the _EL1 and _EL2 registers.

However, most of the resulting definitions aren't actually used by
anybody and have subsequently started to bit-rot when new fields have
been added by the architecture, resulting in fields being part of the
RES0 mask despite being defined and used elsewhere.

Rather than fix up these masks, simply remove the unused parts entirely
so that we can drop the maintenance burden. We can always add things
back if we need them in the future.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

The ESR.EC encoding of 0b011010 (0x1a) describes an exception generated
by an ERET, ERETAA or ERETAB instruction as a result of a nested
virtualisation trap to EL2.

Add an encoding for this EC and a string description so that we identify
it correctly if we take one unexpectedly.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>

In commit b6b27355
("tracing: Use str_has_prefix() instead of using fixed sizes")
the newly introduced str_has_prefix() was used
to replace error-prone strncmp(str, const, len).
Here fix codes with the same pattern.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Will Deacon <will@kernel.org>

Commit 36a2ba07 ("ACPI/IORT: Reject platform device creation on NUMA
node mapping failure") introduced a local variable 'node' in
arm_smmu_v3_set_proximity() that shadows the struct acpi_iort_node
pointer function parameter.

Execution was unaffected but it is prone to errors and can lead
to subtle bugs.

Rename the local variable to prevent any issue.
Reviewed-by: Hanjun Guo <guohanjun@huawei.com>
Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Hanjun Guo <guohanjun@huawei.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Will Deacon <will@kernel.org>

stat.h is listed in include/uapi/asm-generic/Kbuild, so Kbuild will
automatically generate it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Will Deacon <will@kernel.org>

With commit b6664ba4 ("s390, kexec_file: drop arch_kexec_mem_walk()"),
we introduced the KEXEC_BUF_MEM_UNKNOWN macro. If kexec_buf.mem is set
to this value, kexec_locate_mem_hole() will try to allocate free memory.

While other arch(s) like s390 and x86_64 already use this macro to
initialize kexec_buf.mem with, arm64 uses an equivalent value of 0.
Replace it with KEXEC_BUF_MEM_UNKNOWN, to keep the convention of
initializing 'kxec_buf.mem' consistent across various archs.

Cc: takahiro.akashi@linaro.org
Cc: james.morse@arm.com
Reviewed-by: Matthias Brugger <mbrugger@suse.com>
Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>

For a number of years, UAPI headers have been split from kernel-internal
headers. The latter are never exposed to userspace, and always built
with __KERNEL__ defined.

Most headers under arch/arm64 don't have __KERNEL__ guards, but there
are a few stragglers lying around. To make things more consistent, and
to set a good example going forward, let's remove these redundant
__KERNEL__ guards.

In a couple of cases, a trailing #endif lacked a comment describing its
corresponding #if or #ifdef, so these are fixes up at the same time.

Guards in auto-generated crypto code are left as-is, as these guards are
generated by scripting imported from the upstream openssl project
scripts. Guards in UAPI headers are left as-is, as these can be included
by userspace or the kernel.

There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

As of commit 4141c857 ("arm64: convert
raw syscall invocation to C"), moving syscall handling from assembly to
C, the macro mask_nospec64 is no longer referenced.
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

Pull tpm fixes from Jarkko Sakkinen:
 "Two bug fixes that did not make into my first pull request"

* tag 'tpmdd-next-20190805' of git://git.infradead.org/users/jjs/linux-tpmdd:
  tpm: tpm_ibm_vtpm: Fix unallocated banks
  tpm: Fix null pointer dereference on chip register error path

Pull MTD fixes from Miquel Raynal:
 "NAND:

   - Fix Micron driver as some chips enable internal ECC correction
     during their discovery while they advertize they do not have any.

  Hyperbus:

   - Restrict the build to only ARM64 SoCs (and compile testing) which
     is what should have been done since the beginning.

   - Fix Kconfig issue by selection something instead of implying it"

* tag 'mtd/fixes-for-5.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux:
  mtd: hyperbus: Add hardware dependency to AM654 driver
  mtd: hyperbus: Kconfig: Fix HBMC_AM654 dependencies
  mtd: rawnand: micron: handle on-die "ECC-off" devices correctly

The nr_allocated_banks and allocated banks are initialized as part of
tpm_chip_register. Currently, this is done as part of auto startup
function. However, some drivers, like the ibm vtpm driver, do not run
auto startup during initialization. This results in uninitialized memory
issue and causes a kernel panic during boot.

This patch moves the pcr allocation outside the auto startup function
into tpm_chip_register. This ensures that allocated banks are initialized
in any case.

Fixes: 879b5892 ("tpm: retrieve digest size of unknown algorithms with PCR read")
Reported-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Michal Suchánek <msuchanek@suse.de>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

If clk_enable is not defined and chip initialization
is canceled code hits null dereference.

Easily reproducible with vTPM init fail:
  swtpm chardev --tpmstate dir=nonexistent_dir --tpm2 --vtpm-proxy

BUG: kernel NULL pointer dereference, address: 00000000
...
Call Trace:
 tpm_chip_start+0x9d/0xa0 [tpm]
 tpm_chip_register+0x10/0x1a0 [tpm]
 vtpm_proxy_work+0x11/0x30 [tpm_vtpm_proxy]
 process_one_work+0x214/0x5a0
 worker_thread+0x134/0x3e0
 ? process_one_work+0x5a0/0x5a0
 kthread+0xd4/0x100
 ? process_one_work+0x5a0/0x5a0
 ? kthread_park+0x90/0x90
 ret_from_fork+0x19/0x24

Fixes: 719b7d81 ("tpm: introduce tpm_chip_start() and tpm_chip_stop()")
Cc: stable@vger.kernel.org # v5.1+
Signed-off-by: Milan Broz <gmazyland@gmail.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

Pull powerpc fixes from Michael Ellerman:
 "Some more powerpc fixes for 5.3:

   - Wire up the new clone3 syscall.

   - A fix for the PAPR SCM nvdimm driver, to fix a crash when firmware
     gives us a device that's attached to a non-online NUMA node.

   - A fix for a boot failure on 32-bit with KASAN enabled.

   - Three fixes for implicit fall through warnings, some of which are
     errors for us due to -Werror.

  Thanks to: Aneesh Kumar K.V, Christophe Leroy, Kees Cook, Santosh
  Sivaraj, Stephen Rothwell"

* tag 'powerpc-5.3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/kasan: fix early boot failure on PPC32
  drivers/macintosh/smu.c: Mark expected switch fall-through
  powerpc/spe: Mark expected switch fall-throughs
  powerpc/nvdimm: Pick nearby online node if the device node is not online
  powerpc/kvm: Fall through switch case explicitly
  powerpc: Wire up clone3 syscall

At the end of the v5.3 upstream kernel development cycle, Simon will be
stepping down from his role as Renesas SoC maintainer.  Starting with
the v5.4 development cycle, Geert is taking over this role.

Add Geert as a co-maintainer, and add his git repository and branch.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'kbuild-fixes-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - detect missing missing "WITH Linux-syscall-note" for uapi headers

 - fix needless rebuild when using Clang

 - fix false-positive cc-option in Kconfig when using Clang

 - avoid including corrupted .*.cmd files in the modpost stage

 - fix warning of 'make vmlinux'

 - fix {m,n,x,g}config to not generate the broken .config on the second
   save operation.

 - some trivial Makefile fixes

* tag 'kbuild-fixes-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: Clear "written" flag to avoid data loss
  kbuild: Check for unknown options with cc-option usage in Kconfig and clang
  lib/raid6: fix unnecessary rebuild of vpermxor*.c
  kbuild: modpost: do not parse unnecessary rules for vmlinux modpost
  kbuild: modpost: remove unnecessary dependency for __modpost
  kbuild: modpost: handle KBUILD_EXTRA_SYMBOLS only for external modules
  kbuild: modpost: include .*.cmd files only when targets exist
  kbuild: initialize CLANG_FLAGS correctly in the top Makefile
  kbuild: detect missing "WITH Linux-syscall-note" for uapi headers

Pull SafeSetID maintainer update from Micah Morton:
 "Add entry in MAINTAINERS file for SafeSetID LSM"

* tag 'safesetid-maintainers-correction-5.3-rc2' of git://github.com/micah-morton/linux:
  Add entry in MAINTAINERS file for SafeSetID LSM

Prior to this commit, starting nconfig, xconfig or gconfig, and saving
the .config file more than once caused data loss, where a .config file
that contained only comments would be written to disk starting from the
second save operation.

This bug manifests itself because the SYMBOL_WRITTEN flag is never
cleared after the first call to conf_write, and subsequent calls to
conf_write then skip all of the configuration symbols due to the
SYMBOL_WRITTEN flag being set.

This commit resolves this issue by clearing the SYMBOL_WRITTEN flag
from all symbols before conf_write returns.

Fixes: 8e2442a5 ("kconfig: fix missing choice values in auto.conf")
Cc: linux-stable <stable@vger.kernel.org> # 4.19+
Signed-off-by: M. Vefa Bicakci <m.v.b@runbox.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Pull Xtensa fix from Max Filippov:
 "Fix build for xtensa cores with coprocessors that was broken by
  entry/return abstraction patch"

* tag 'xtensa-20190803' of git://github.com/jcmvbkbc/linux-xtensa:
  xtensa: fix build for cores with coprocessors

Pull i2c fixes from Wolfram Sang:
 "A set of driver fixes for the I2C subsystem"

* 'i2c/for-current-fixed' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: s3c2410: Mark expected switch fall-through
  i2c: at91: fix clk_offset for sama5d2
  i2c: at91: disable TXRDY interrupt after sending data
  i2c: iproc: Fix i2c master read more than 63 bytes
  eeprom: at24: make spd world-readable again

Pull perf tooling fixes from Thomas Gleixner:
 "A set of updates for perf tools and documentation:

  perf header:
    - Prevent a division by zero
    - Deal with an uninitialized warning proper

  libbpf:
    - Fix the missiong __WORDSIZE definition for musl & al

  UAPI headers:
    - Synchronize kernel headers

  Documentation:
    - Fix the memory units for perf.data size"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  libbpf: fix missing __WORDSIZE definition
  perf tools: Fix perf.data documentation units for memory size
  perf header: Fix use of unitialized value warning
  perf header: Fix divide by zero error if f_header.attr_size==0
  tools headers UAPI: Sync if_link.h with the kernel
  tools headers UAPI: Sync sched.h with the kernel
  tools headers UAPI: Sync usbdevice_fs.h with the kernels to get new ioctl
  tools perf beauty: Fix usbdevfs_ioctl table generator to handle _IOC()
  tools headers UAPI: Update tools's copy of drm.h headers
  tools headers UAPI: Update tools's copy of mman.h headers
  tools headers UAPI: Update tools's copy of kvm.h headers
  tools include UAPI: Sync x86's syscalls_64.tbl and generic unistd.h to pick up clone3 and pidfd_open