pte_accessible() is used by ptep_clear_flush() to figure out whether TLB
invalidation is necessary when unmapping pages for reclaim. Although our
implementation is correct according to the architecture, returning true
only for valid, young ptes in the absence of racing page-table
modifications, this is in fact flawed due to lazy invalidation of old
ptes in ptep_clear_flush_young() where we elide the expensive DSB
instruction for completing the TLB invalidation.

Rather than penalise the aging path, adjust pte_accessible() to return
true for any valid pte, even if the access flag is cleared.

Cc: <stable@vger.kernel.org>
Fixes: 76c714be

 ("arm64: pgtable: implement pte_accessible()")
Reported-by: Yu Zhao <yuzhao@google.com>
Acked-by: Yu Zhao <yuzhao@google.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201120143557.6715-2-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Fix following warnings caused by mismatch between
function parameters and function comments.

drivers/acpi/arm64/iort.c:55: warning: Function parameter or member 'iort_node' not described in 'iort_set_fwnode'
drivers/acpi/arm64/iort.c:55: warning: Excess function parameter 'node' description in 'iort_set_fwnode'
drivers/acpi/arm64/iort.c:682: warning: Function parameter or member 'id' not described in 'iort_get_device_domain'
drivers/acpi/arm64/iort.c:682: warning: Function parameter or member 'bus_token' not described in 'iort_get_device_domain'
drivers/acpi/arm64/iort.c:682: warning: Excess function parameter 'req_id' description in 'iort_get_device_domain'
drivers/acpi/arm64/iort.c:1142: warning: Function parameter or member 'dma_size' not described in 'iort_dma_setup'
drivers/acpi/arm64/iort.c:1142: warning: Excess function parameter 'size' description in 'iort_dma_setup'
drivers/acpi/arm64/iort.c:1534: warning: Function parameter or member 'ops' not described in 'iort_add_platform_device'

Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
Acked-by: Hanjun Guo <guohanjun@huawei.com>
Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Link: https://lore.kernel.org/r/20201014093139.1580-1-shiju.jose@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>

Adding <asm/exception.h> brought in <asm/kprobes.h> which uses
<asm/probes.h>, which uses 'pstate_check_t' so the latter needs to
#include <asm/insn.h> for this typedef.

Fixes this build error:

  In file included from arch/arm64/include/asm/kprobes.h:24,
                    from arch/arm64/include/asm/exception.h:11,
                    from arch/arm64/kernel/fpsimd.c:35:
  arch/arm64/include/asm/probes.h:16:2: error: unknown type name 'pstate_check_t'
      16 |  pstate_check_t *pstate_cc;

Fixes: c6b90d5c

 ("arm64/fpsimd: Fix missing-prototypes in fpsimd.c")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: Tian Tao <tiantao6@hisilicon.com>
Link: https://lore.kernel.org/r/20201123044510.9942-1-rdunlap@infradead.org
Signed-off-by: Will Deacon <will@kernel.org>

QCOM KRYO2XX Silver cores are Cortex-A53 based and are
susceptible to the 845719 erratum. Add them to the lookup
list to apply the erratum.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Link: https://lore.kernel.org/r/20201104232218.198800-5-konrad.dybcio@somainline.org
Signed-off-by: Will Deacon <will@kernel.org>

KRYO2XX silver (LITTLE) CPUs are based on Cortex-A53
and they are not affected by spectre-v2.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Link: https://lore.kernel.org/r/20201104232218.198800-4-konrad.dybcio@somainline.org
Signed-off-by: Will Deacon <will@kernel.org>

QCOM KRYO2XX gold (big) silver (LITTLE) CPU cores are based on
Cortex-A73 and Cortex-A53 respectively and are meltdown safe,
hence add them to kpti_safe_list[].

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Link: https://lore.kernel.org/r/20201104232218.198800-3-konrad.dybcio@somainline.org
Signed-off-by: Will Deacon <will@kernel.org>

Add MIDR value for KRYO2XX gold (big) and silver (LITTLE)
CPU cores which are used in Qualcomm Technologies, Inc.
SoCs. This will be used to identify and apply errata
which are applicable for these CPU cores.

Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Link: https://lore.kernel.org/r/20201104232218.198800-2-konrad.dybcio@somainline.org
Signed-off-by: Will Deacon <will@kernel.org>

During memory hotplug process, the linear mapping should not be created for
a given memory range if that would fall outside the maximum allowed linear
range. Else it might cause memory corruption in the kernel virtual space.

Maximum linear mapping region is [PAGE_OFFSET..(PAGE_END -1)] accommodating
both its ends but excluding PAGE_END. Max physical range that can be mapped
inside this linear mapping range, must also be derived from its end points.

This ensures that arch_add_memory() validates memory hot add range for its
potential linear mapping requirements, before creating it with
__create_pgd_mapping().

Fixes: 4ab21506

 ("arm64: Add memory hotplug support")
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Link: https://lore.kernel.org/r/1605252614-761-1-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

Commit ce3d31ad

 ("arm64/smp: Move rcu_cpu_starting() earlier") ensured
that RCU is informed early about incoming CPUs that might end up calling
into printk() before they are online. However, if such a CPU fails the
early CPU feature compatibility checks in check_local_cpu_capabilities(),
then it will be powered off or parked without informing RCU, leading to
an endless stream of stalls:

  | rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
  | rcu:	2-O...: (0 ticks this GP) idle=002/1/0x4000000000000000 softirq=0/0 fqs=2593
  | (detected by 0, t=5252 jiffies, g=9317, q=136)
  | Task dump for CPU 2:
  | task:swapper/2       state:R  running task     stack:    0 pid:    0 ppid:     1 flags:0x00000028
  | Call trace:
  | ret_from_fork+0x0/0x30

Ensure that the dying CPU invokes rcu_report_dead() prior to being powered
off or parked.

Cc: Qian Cai <cai@redhat.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Suggested-by: Qian Cai <cai@redhat.com>
Link: https://lore.kernel.org/r/20201105222242.GA8842@willie-the-truck
Link: https://lore.kernel.org/r/20201106103602.9849-3-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

cpu_psci_cpu_die() is called in the context of the dying CPU, which
will no longer be online or tracked by RCU. It is therefore not generally
safe to call printk() if the PSCI "cpu off" request fails, so remove the
pr_crit() invocation.

Cc: Qian Cai <cai@redhat.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201106103602.9849-2-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Sparse gets cross about us returning 0 from image_load(), which has a
return type of 'void *':

>> arch/arm64/kernel/kexec_image.c:130:16: sparse: sparse: Using plain integer as NULL pointer

Return NULL instead, as we don't use the return value for anything if it
does not indicate an error.

Cc: Benjamin Gwin <bgwin@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 108aa503

 ("arm64: kexec_file: try more regions if loading segments fails")
Link: https://lore.kernel.org/r/202011091736.T0zH8kaC-lkp@intel.com
Signed-off-by: Will Deacon <will@kernel.org>

In a surprising turn of events, it transpires that CPU capabilities
configured as ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE are never set as the
result of late-onlining. Therefore our handling of erratum 1418040 does
not get activated if it is not required by any of the boot CPUs, even
though we allow late-onlining of an affected CPU.

In order to get things working again, replace the cpus_have_const_cap()
invocation with an explicit check for the current CPU using
this_cpu_has_cap().

Cc: Sai Prakash Ranjan <saiprakash.ranjan@codeaurora.org>
Cc: Stephen Boyd <swboyd@chromium.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201106114952.10032-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

It's possible that the first region picked for the new kernel will make
it impossible to fit the other segments in the required 32GB window,
especially if we have a very large initrd.

Instead of giving up, we can keep testing other regions for the kernel
until we find one that works.

Suggested-by: Ryan O'Leary <ryanoleary@google.com>
Signed-off-by: Benjamin Gwin <bgwin@google.com>
Link: https://lore.kernel.org/r/20201103201106.2397844-1-bgwin@google.com
Signed-off-by: Will Deacon <will@kernel.org>

Commit 36dadef2 ("kprobes: Init kprobes in early_initcall") enabled
using kprobes from early_initcall. Unfortunately at this point the
hardware debug infrastructure is not operational. The OS lock may still
be locked, and the hardware watchpoints may have unknown values when
kprobe enables debug monitors to single-step instructions.

Rather than using hardware single-step, append a BRK instruction after
the instruction to be executed out-of-line.

Fixes: 36dadef2

 ("kprobes: Init kprobes in early_initcall")
Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lore.kernel.org/r/20201103134900.337243-1-jean-philippe@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>

The current arm64 default config limits max NUMA nodes available on
system to 4 (NODES_SHIFT = 2). Today's arm64 systems can reach or
exceed 16 NUMA nodes. To accomodate current hardware and to fit
NODES_SHIFT within page flags on arm64, increase NODES_SHIFT to 4.

Signed-off-by: Vanshidhar Konda <vanshikonda@os.amperecomputing.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20201020173409.1266576-1-vanshikonda@os.amperecomputing.com/
Link: https://lore.kernel.org/r/20201030173050.1182876-1-vanshikonda@os.amperecomputing.com
Signed-off-by: Will Deacon <will@kernel.org>

Commit 39d114dd ("arm64: add KASAN support") added .weak directives to
arch/arm64/lib/mem*.S instead of changing the existing SYM_FUNC_START_PI
macros. This can lead to the assembly snippet `.weak memcpy ... .globl
memcpy` which will produce a STB_WEAK memcpy with GNU as but STB_GLOBAL
memcpy with LLVM's integrated assembler before LLVM 12. LLVM 12 (since
https://reviews.llvm.org/D90108) will error on such an overridden symbol
binding.

Use the appropriate SYM_FUNC_START_WEAK_PI instead.

Fixes: 39d114dd

 ("arm64: add KASAN support")
Reported-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20201029181951.1866093-1-maskray@google.com
Signed-off-by: Will Deacon <will@kernel.org>

The call to rcu_cpu_starting() in secondary_start_kernel() is not early
enough in the CPU-hotplug onlining process, which results in lockdep
splats as follows:

 WARNING: suspicious RCU usage
 -----------------------------
 kernel/locking/lockdep.c:3497 RCU-list traversed in non-reader section!!

 other info that might help us debug this:

 RCU used illegally from offline CPU!
 rcu_scheduler_active = 1, debug_locks = 1
 no locks held by swapper/1/0.

 Call trace:
  dump_backtrace+0x0/0x3c8
  show_stack+0x14/0x60
  dump_stack+0x14c/0x1c4
  lockdep_rcu_suspicious+0x134/0x14c
  __lock_acquire+0x1c30/0x2600
  lock_acquire+0x274/0xc48
  _raw_spin_lock+0xc8/0x140
  vprintk_emit+0x90/0x3d0
  vprintk_default+0x34/0x40
  vprintk_func+0x378/0x590
  printk+0xa8/0xd4
  __cpuinfo_store_cpu+0x71c/0x868
  cpuinfo_store_cpu+0x2c/0xc8
  secondary_start_kernel+0x244/0x318

This is avoided by moving the call to rcu_cpu_starting up near the
beginning of the secondary_start_kernel() function.

Signed-off-by: Qian Cai <cai@redhat.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/lkml/160223032121.7002.1269740091547117869.tip-bot2@tip-bot2/
Link: https://lore.kernel.org/r/20201028182614.13655-1-cai@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>

On Cortex-A77 r0p0 and r1p0, a sequence of a non-cacheable or device load
and a store exclusive or PAR_EL1 read can cause a deadlock.

The workaround requires a DMB SY before and after a PAR_EL1 register
read. In addition, it's possible an interrupt (doing a device read) or
KVM guest exit could be taken between the DMB and PAR read, so we
also need a DMB before returning from interrupt and before returning to
a guest.

A deadlock is still possible with the workaround as KVM guests must also
have the workaround. IOW, a malicious guest can deadlock an affected
systems.

This workaround also depends on a firmware counterpart to enable the h/w
to insert DMB SY after load and store exclusive instructions. See the
errata document SDEN-1152370 v10 [1] for more information.

[1] https://static.docs.arm.com/101992/0010/Arm_Cortex_A77_MP074_Software_Developer_Errata_Notice_v10.pdf

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: kvmarm@lists.cs.columbia.edu
Link: https://lore.kernel.org/r/20201028182839.166037-2-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Add the MIDR part number info for the Arm Cortex-A77.

Signed-off-by: Rob Herring <robh@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201028182839.166037-1-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

On exception entry, the kernel explicitly resets the PSTATE.TCO (tag
check override) so that any kernel memory accesses will be checked (the
bit is restored on exception return). This has the side-effect that the
uaccess routines will not honour the PSTATE.TCO that may have been set
by the user prior to a syscall.

There is no issue in practice since PSTATE.TCO is expected to be used
only for brief periods in specific routines (e.g. garbage collection).
To control the tag checking mode of the uaccess routines, the user will
have to invoke a corresponding prctl() call.

Document the kernel behaviour w.r.t. PSTATE.TCO accordingly.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Fixes: df9d7a22

 ("arm64: mte: Add Memory Tagging Extension documentation")
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Szabolcs Nagy <szabolcs.nagy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

Geert reports that commit be288182

 ("arm64/build: Assert for
unwanted sections") results in build errors on arm64 for configurations
that have CONFIG_MODULES disabled.

The commit in question added ASSERT()s to the arm64 linker script to
ensure that linker generated sections such as .got.plt etc are empty,
but as it turns out, there are corner cases where the linker does emit
content into those sections. More specifically, weak references to
function symbols (which can remain unsatisfied, and can therefore not
be emitted as relative references) will be emitted as GOT and PLT
entries when linking the kernel in PIE mode (which is the case when
CONFIG_RELOCATABLE is enabled, which is on by default).

What happens is that code such as

	struct device *(*fn)(struct device *dev);
	struct device *iommu_device;

	fn = symbol_get(mdev_get_iommu_device);
	if (fn) {
		iommu_device = fn(dev);

essentially gets converted into the following when CONFIG_MODULES is off:

	struct device *iommu_device;

	if (&mdev_get_iommu_device) {
		iommu_device = mdev_get_iommu_device(dev);

where mdev_get_iommu_device is emitted as a weak symbol reference into
the object file. The first reference is decorated with an ordinary
ABS64 data relocation (which yields 0x0 if the reference remains
unsatisfied). However, the indirect call is turned into a direct call
covered by a R_AARCH64_CALL26 relocation, which is converted into a
call via a PLT entry taking the target address from the associated
GOT entry.

Given that such GOT and PLT entries are unnecessary for fully linked
binaries such as the kernel, let's give these weak symbol references
hidden visibility, so that the linker knows that the weak reference
via R_AARCH64_CALL26 can simply remain unsatisfied.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Fangrui Song <maskray@google.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20201027151132.14066-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Commit 76085aff ("efi/libstub/arm64: align PE/COFF sections to segment
alignment") increased the PE/COFF section alignment to match the minimum
segment alignment of the kernel image, which ensures that the kernel does
not need to be moved around in memory by the EFI stub if it was built as
relocatable.

However, the first PE/COFF section starts at _stext, which is only 4 KB
aligned, and so the section layout is inconsistent. Existing EFI loaders
seem to care little about this, but it is better to clean this up.

So let's pad the header to 64 KB to match the PE/COFF section alignment.

Fixes: 76085aff

 ("efi/libstub/arm64: align PE/COFF sections to segment alignment")
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20201027073209.2897-2-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Now that we started making the linker warn about orphan sections
(input sections that are not explicitly consumed by an output section),
some configurations produce the following warning:

  aarch64-linux-gnu-ld: warning: orphan section `.igot.plt' from
         `arch/arm64/kernel/head.o' being placed in section `.igot.plt'

It could be any file that triggers this - head.o is simply the first
input file in the link - and the resulting .igot.plt section never
actually appears in vmlinux as it turns out to be empty.

So let's add .igot.plt to our collection of input sections to disregard
unless they are empty.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20201028133332.5571-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

The check_user_mem test reports the error below because the test
plan is not declared correctly:

  # Planned tests != run tests (0 != 4)

Fix the test adding the correct test plan declaration.

Fixes: 4dafc08d

 ("kselftest/arm64: Check mte tagged user address in kernel")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Gabor Kertesz <gabor.kertesz@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Link: https://lore.kernel.org/r/20201026121248.2340-7-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

The check_ksm_options test reports the error below because the test
plan is not declared correctly:

  # Planned tests != run tests (0 != 4)

Fix the test adding the correct test plan declaration.

Fixes: f981d8fa

 ("kselftest/arm64: Verify KSM page merge for MTE pages")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Gabor Kertesz <gabor.kertesz@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Link: https://lore.kernel.org/r/20201026121248.2340-6-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

The check_mmap_options test reports the error below because the test
plan is not declared correctly:

  # Planned tests != run tests (0 != 22)

Fix the test adding the correct test plan declaration.

Fixes: 53ec81d2

 ("kselftest/arm64: Verify all different mmap MTE options")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Gabor Kertesz <gabor.kertesz@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Link: https://lore.kernel.org/r/20201026121248.2340-5-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

The check_child_memory test reports the error below because the test
plan is not declared correctly:

  # Planned tests != run tests (0 != 12)

Fix the test adding the correct test plan declaration.

Fixes: dfe537cf

 ("kselftest/arm64: Check forked child mte memory accessibility")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Gabor Kertesz <gabor.kertesz@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Link: https://lore.kernel.org/r/20201026121248.2340-4-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

The check_tags_inclusion test reports the error below because the test
plan is not declared correctly:

  # Planned tests != run tests (0 != 4)

Fix the test adding the correct test plan declaration.

Fixes: f3b2a26c

 ("kselftest/arm64: Verify mte tag inclusion via prctl")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Gabor Kertesz <gabor.kertesz@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Link: https://lore.kernel.org/r/20201026121248.2340-3-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

The check_buffer_fill test reports the error below because the test
plan is not declared correctly:

  # Planned tests != run tests (0 != 20)

Fix the test adding the correct test plan declaration.

Fixes: e9b60476

 ("kselftest/arm64: Add utilities and a test to validate mte memory")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Gabor Kertesz <gabor.kertesz@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Link: https://lore.kernel.org/r/20201026121248.2340-2-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>

The icache_policy_str[] definition causes a warning when extra
warning flags are enabled:

arch/arm64/kernel/cpuinfo.c:38:26: warning: initialized field overwritten [-Woverride-init]
   38 |  [ICACHE_POLICY_VIPT]  = "VIPT",
      |                          ^~~~~~
arch/arm64/kernel/cpuinfo.c:38:26: note: (near initialization for 'icache_policy_str[2]')
arch/arm64/kernel/cpuinfo.c:39:26: warning: initialized field overwritten [-Woverride-init]
   39 |  [ICACHE_POLICY_PIPT]  = "PIPT",
      |                          ^~~~~~
arch/arm64/kernel/cpuinfo.c:39:26: note: (near initialization for 'icache_policy_str[3]')
arch/arm64/kernel/cpuinfo.c:40:27: warning: initialized field overwritten [-Woverride-init]
   40 |  [ICACHE_POLICY_VPIPT]  = "VPIPT",
      |                           ^~~~~~~
arch/arm64/kernel/cpuinfo.c:40:27: note: (near initialization for 'icache_policy_str[0]')

There is no real need for the default initializer here, as printing a
NULL string is harmless. Rewrite the logic to have an explicit
reserved value for the only one that uses the default value.

This partially reverts the commit that removed ICACHE_POLICY_AIVIVT.

Fixes: 155433cb

 ("arm64: cache: Remove support for ASID-tagged VIVT I-caches")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201026193807.3816388-1-arnd@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

According to the SMCCC spec[1](7.5.2 Discovery) the
ARM_SMCCC_ARCH_WORKAROUND_1 function id only returns 0, 1, and
SMCCC_RET_NOT_SUPPORTED.

 0 is "workaround required and safe to call this function"
 1 is "workaround not required but safe to call this function"
 SMCCC_RET_NOT_SUPPORTED is "might be vulnerable or might not be, who knows, I give up!"

SMCCC_RET_NOT_SUPPORTED might as well mean "workaround required, except
calling this function may not work because it isn't implemented in some
cases". Wonderful. We map this SMC call to

 0 is SPECTRE_MITIGATED
 1 is SPECTRE_UNAFFECTED
 SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE

For KVM hypercalls (hvc), we've implemented this function id to return
SMCCC_RET_NOT_SUPPORTED, 0, and SMCCC_RET_NOT_REQUIRED. One of those
isn't supposed to be there. Per the code we call
arm64_get_spectre_v2_state() to figure out what to return for this
feature discovery call.

 0 is SPECTRE_MITIGATED
 SMCCC_RET_NOT_REQUIRED is SPECTRE_UNAFFECTED
 SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE

Let's clean this up so that KVM tells the guest this mapping:

 0 is SPECTRE_MITIGATED
 1 is SPECTRE_UNAFFECTED
 SMCCC_RET_NOT_SUPPORTED is SPECTRE_VULNERABLE

Note: SMCCC_RET_NOT_AFFECTED is 1 but isn't part of the SMCCC spec

Fixes: c118bbb5

 ("arm64: KVM: Propagate full Spectre v2 workaround state to KVM guests")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://developer.arm.com/documentation/den0028/latest [1]
Link: https://lore.kernel.org/r/20201023154751.1973872-1-swboyd@chromium.org
Signed-off-by: Will Deacon <will@kernel.org>

As it stands now, the vdso32 Makefile hardcodes the linker to ld.bfd
using -fuse-ld=bfd with $(CC). This was taken from the arm vDSO
Makefile, as the comment notes, done in commit d2b30cd4 ("ARM:
8384/1: VDSO: force use of BFD linker").

Commit fe00e50b ("ARM: 8858/1: vdso: use $(LD) instead of $(CC) to
link VDSO") changed that Makefile to use $(LD) directly instead of
through $(CC), which matches how the rest of the kernel operates. Since
then, LD=ld.lld means that the arm vDSO will be linked with ld.lld,
which has shown no problems so far.

Allow ld.lld to link this vDSO as we do the regular arm vDSO. To do
this, we need to do a few things:

* Add a LD_COMPAT variable, which defaults to $(CROSS_COMPILE_COMPAT)ld
  with gcc and $(LD) if LLVM is 1, which will be ld.lld, or
  $(CROSS_COMPILE_COMPAT)ld if not, which matches the logic of the main
  Makefile. It is overrideable for further customization and avoiding
  breakage.

* Eliminate cc32-ldoption, which matches commit 055efab3

 ("kbuild:
  drop support for cc-ldoption").

With those, we can use $(LD_COMPAT) in cmd_ldvdso and change the flags
from compiler linker flags to linker flags directly. We eliminate
-mfloat-abi=soft because it is not handled by the linker.

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1033
Link: https://lore.kernel.org/r/20201020011406.1818918-1-natechancellor@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>

Use a more generic form for __section that requires quotes to avoid
complications with clang and gcc differences.

Remove the quote operator # from compiler_attributes.h __section macro.

Convert all unquoted __section(foo) uses to quoted __section("foo").
Also convert __attribute__((section("foo"))) uses to __section("foo")
even if the __attribute__ has multiple list entry forms.

Conversion done using the script at:

    https://lore.kernel.org/lkml/75393e5ddc272dc7403de74d645e6c6e0f4e70eb.camel@perches.com/2-convert_section.pl

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@gooogle.com>
Reviewed-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

tid_addr is not a "pointer to (pointer to int in userspace)"; it is in
fact a "pointer to (pointer to int in userspace) in userspace".  So
sparse rightfully complains about passing a kernel pointer to
put_user().

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 453431a5

 ("mm, treewide: rename kzfree() to
kfree_sensitive()") renamed kzfree() to kfree_sensitive(),
but it left a compatibility definition of kzfree() to avoid
being too disruptive.

Since then a few more instances of kzfree() have slipped in.

Just get rid of them and remove the compatibility definition
once and for all.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

If set, use the environment variable GIT_DIR to change the default .git
location of the kernel git tree.

If GIT_DIR is unset, keep using the current ".git" default.

Link: https://lkml.kernel.org/r/c5e23b45562373d632fccb8bc04e563abba4dd1d.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull timer fixes from Thomas Gleixner:
 "A time namespace fix and a matching selftest. The futex absolute
  timeouts which are based on CLOCK_MONOTONIC require time namespace
  corrected. This was missed in the original time namesapce support"

* tag 'timers-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  selftests/timens: Add a test for futex()
  futex: Adjust absolute futex timeouts with per time namespace offset

Pull scheduler fixes from Thomas Gleixner:
 "Two scheduler fixes:

   - A trivial build fix for sched_feat() to compile correctly with
     CONFIG_JUMP_LABEL=n

   - Replace a zero lenght array with a flexible array"

* tag 'sched-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/features: Fix !CONFIG_JUMP_LABEL case
  sched: Replace zero-length array with flexible-array

Pull perf fix from Thomas Gleixner:
 "A single fix to compute the field offset of the SNOOPX bit in the data
  source bitmask of perf events correctly"

* tag 'perf-urgent-2020-10-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: correct SNOOPX field offset