Commit Graph

3409 Commits

Author SHA1 Message Date
Kefeng Wang
34f8602e30 arm: convert to setup_initial_init_mm()
Use setup_initial_init_mm() helper to simplify code.

Link: https://lkml.kernel.org/r/20210608083418.137226-4-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:21 -07:00
Linus Torvalds
77d34a4683 Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM development updates from Russell King:

 - Make it clear __swp_entry_to_pte() uses PTE_TYPE_FAULT

 - Updates for setting vmalloc size via command line to resolve an issue
   with the 8MiB hole not properly being accounted for, and clean up the
   code.

 - ftrace support for module PLTs

 - Spelling fixes

 - kbuild updates for removing generated files and pattern rules for
   generating files

 - Clang/llvm updates

 - Change the way the kernel is mapped, placing it in vmalloc space
   instead.

 - Remove arm_pm_restart from arm and aarch64.

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (29 commits)
  ARM: 9098/1: ftrace: MODULE_PLT: Fix build problem without DYNAMIC_FTRACE
  ARM: 9097/1: mmu: Declare section start/end correctly
  ARM: 9096/1: Remove arm_pm_restart()
  ARM: 9095/1: ARM64: Remove arm_pm_restart()
  ARM: 9094/1: Register with kernel restart handler
  ARM: 9093/1: drivers: firmwapsci: Register with kernel restart handler
  ARM: 9092/1: xen: Register with kernel restart handler
  ARM: 9091/1: Revert "mm: qsd8x50: Fix incorrect permission faults"
  ARM: 9090/1: Map the lowmem and kernel separately
  ARM: 9089/1: Define kernel physical section start and end
  ARM: 9088/1: Split KERNEL_OFFSET from PAGE_OFFSET
  ARM: 9087/1: kprobes: test-thumb: fix for LLVM_IAS=1
  ARM: 9086/1: syscalls: use pattern rules to generate syscall headers
  ARM: 9085/1: remove unneeded abi parameter to syscallnr.sh
  ARM: 9084/1: simplify the build rule of mach-types.h
  ARM: 9083/1: uncompress: atags_to_fdt: Spelling s/REturn/Return/
  ARM: 9082/1: [v2] mark prepare_page_table as __init
  ARM: 9079/1: ftrace: Add MODULE_PLTS support
  ARM: 9078/1: Add warn suppress parameter to arm_gen_branch_link()
  ARM: 9077/1: PLT: Move struct plt_entries definition to header
  ...
2021-07-06 11:52:58 -07:00
Alex Sverdlin
6fa630bf47 ARM: 9098/1: ftrace: MODULE_PLT: Fix build problem without DYNAMIC_FTRACE
FTRACE_ADDR is only defined when CONFIG_DYNAMIC_FTRACE is defined, the
latter is even stronger requirement than CONFIG_FUNCTION_TRACER (which is
enough for MCOUNT_ADDR).

Link: https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org/thread/ZUVCQBHDMFVR7CCB7JPESLJEWERZDJ3T/

Fixes: 1f12fb25c5c5d22f ("ARM: 9079/1: ftrace: Add MODULE_PLTS support")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-07-05 11:52:26 +01:00
Linus Torvalds
21edf50948 Merge tag 'irq-core-2021-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "Updates for the interrupt subsystem:

  Core changes:

   - Cleanup and simplification of common code to invoke the low level
     interrupt flow handlers when this invocation requires irqdomain
     resolution. Add the necessary core infrastructure.

   - Provide a proper interface for modular PMU drivers to set the
     interrupt affinity.

   - Add a request flag which allows to exclude interrupts from spurious
     interrupt detection. Useful especially for IPI handlers which
     always return IRQ_HANDLED which turns the spurious interrupt
     detection into a pointless waste of CPU cycles.

  Driver changes:

   - Bulk convert interrupt chip drivers to the new irqdomain low level
     flow handler invocation mechanism.

   - Add device tree bindings for the Renesas R-Car M3-W+ SoC

   - Enable modular build of the Qualcomm PDC driver

   - The usual small fixes and improvements"

* tag 'irq-core-2021-06-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (38 commits)
  dt-bindings: interrupt-controller: arm,gic-v3: Describe GICv3 optional properties
  irqchip: gic-pm: Remove redundant error log of clock bulk
  irqchip/sun4i: Remove unnecessary oom message
  irqchip/irq-imx-gpcv2: Remove unnecessary oom message
  irqchip/imgpdc: Remove unnecessary oom message
  irqchip/gic-v3-its: Remove unnecessary oom message
  irqchip/gic-v2m: Remove unnecessary oom message
  irqchip/exynos-combiner: Remove unnecessary oom message
  irqchip: Bulk conversion to generic_handle_domain_irq()
  genirq: Move non-irqdomain handle_domain_irq() handling into ARM's handle_IRQ()
  genirq: Add generic_handle_domain_irq() helper
  irqchip/nvic: Convert from handle_IRQ() to handle_domain_irq()
  irqdesc: Fix __handle_domain_irq() comment
  genirq: Use irq_resolve_mapping() to implement __handle_domain_irq() and co
  irqdomain: Introduce irq_resolve_mapping()
  irqdomain: Protect the linear revmap with RCU
  irqdomain: Cache irq_data instead of a virq number in the revmap
  irqdomain: Use struct_size() helper when allocating irqdomain
  irqdomain: Make normal and nomap irqdomains exclusive
  powerpc: Move the use of irq_domain_add_nomap() behind a config option
  ...
2021-06-29 12:25:04 -07:00
Linus Torvalds
9840cfcb97 Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
 "There's a reasonable amount here and the juicy details are all below.

  It's worth noting that the MTE/KASAN changes strayed outside of our
  usual directories due to core mm changes and some associated changes
  to some other architectures; Andrew asked for us to carry these [1]
  rather that take them via the -mm tree.

  Summary:

   - Optimise SVE switching for CPUs with 128-bit implementations.

   - Fix output format from SVE selftest.

   - Add support for versions v1.2 and 1.3 of the SMC calling
     convention.

   - Allow Pointer Authentication to be configured independently for
     kernel and userspace.

   - PMU driver cleanups for managing IRQ affinity and exposing event
     attributes via sysfs.

   - KASAN optimisations for both hardware tagging (MTE) and out-of-line
     software tagging implementations.

   - Relax frame record alignment requirements to facilitate 8-byte
     alignment with KASAN and Clang.

   - Cleanup of page-table definitions and removal of unused memory
     types.

   - Reduction of ARCH_DMA_MINALIGN back to 64 bytes.

   - Refactoring of our instruction decoding routines and addition of
     some missing encodings.

   - Move entry code moved into C and hardened against harmful compiler
     instrumentation.

   - Update booting requirements for the FEAT_HCX feature, added to v8.7
     of the architecture.

   - Fix resume from idle when pNMI is being used.

   - Additional CPU sanity checks for MTE and preparatory changes for
     systems where not all of the CPUs support 32-bit EL0.

   - Update our kernel string routines to the latest Cortex Strings
     implementation.

   - Big cleanup of our cache maintenance routines, which were
     confusingly named and inconsistent in their implementations.

   - Tweak linker flags so that GDB can understand vmlinux when using
     RELR relocations.

   - Boot path cleanups to enable early initialisation of per-cpu
     operations needed by KCSAN.

   - Non-critical fixes and miscellaneous cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (150 commits)
  arm64: tlb: fix the TTL value of tlb_get_level
  arm64: Restrict undef hook for cpufeature registers
  arm64/mm: Rename ARM64_SWAPPER_USES_SECTION_MAPS
  arm64: insn: avoid circular include dependency
  arm64: smp: Bump debugging information print down to KERN_DEBUG
  drivers/perf: fix the missed ida_simple_remove() in ddr_perf_probe()
  perf/arm-cmn: Fix invalid pointer when access dtc object sharing the same IRQ number
  arm64: suspend: Use cpuidle context helpers in cpu_suspend()
  PSCI: Use cpuidle context helpers in psci_cpu_suspend_enter()
  arm64: Convert cpu_do_idle() to using cpuidle context helpers
  arm64: Add cpuidle context save/restore helpers
  arm64: head: fix code comments in set_cpu_boot_mode_flag
  arm64: mm: drop unused __pa(__idmap_text_start)
  arm64: mm: fix the count comments in compute_indices
  arm64/mm: Fix ttbr0 values stored in struct thread_info for software-pan
  arm64: mm: Pass original fault address to handle_mm_fault()
  arm64/mm: Drop SECTION_[SHIFT|SIZE|MASK]
  arm64/mm: Use CONT_PMD_SHIFT for ARM64_MEMSTART_SHIFT
  arm64/mm: Drop SWAPPER_INIT_MAP_SIZE
  arm64: Conditionally configure PTR_AUTH key of the kernel.
  ...
2021-06-28 14:04:24 -07:00
Linus Torvalds
54a728dc5e Merge tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler udpates from Ingo Molnar:

 - Changes to core scheduling facilities:

    - Add "Core Scheduling" via CONFIG_SCHED_CORE=y, which enables
      coordinated scheduling across SMT siblings. This is a much
      requested feature for cloud computing platforms, to allow the
      flexible utilization of SMT siblings, without exposing untrusted
      domains to information leaks & side channels, plus to ensure more
      deterministic computing performance on SMT systems used by
      heterogenous workloads.

      There are new prctls to set core scheduling groups, which allows
      more flexible management of workloads that can share siblings.

    - Fix task->state access anti-patterns that may result in missed
      wakeups and rename it to ->__state in the process to catch new
      abuses.

 - Load-balancing changes:

    - Tweak newidle_balance for fair-sched, to improve 'memcache'-like
      workloads.

    - "Age" (decay) average idle time, to better track & improve
      workloads such as 'tbench'.

    - Fix & improve energy-aware (EAS) balancing logic & metrics.

    - Fix & improve the uclamp metrics.

    - Fix task migration (taskset) corner case on !CONFIG_CPUSET.

    - Fix RT and deadline utilization tracking across policy changes

    - Introduce a "burstable" CFS controller via cgroups, which allows
      bursty CPU-bound workloads to borrow a bit against their future
      quota to improve overall latencies & batching. Can be tweaked via
      /sys/fs/cgroup/cpu/<X>/cpu.cfs_burst_us.

    - Rework assymetric topology/capacity detection & handling.

 - Scheduler statistics & tooling:

    - Disable delayacct by default, but add a sysctl to enable it at
      runtime if tooling needs it. Use static keys and other
      optimizations to make it more palatable.

    - Use sched_clock() in delayacct, instead of ktime_get_ns().

 - Misc cleanups and fixes.

* tag 'sched-core-2021-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
  sched/doc: Update the CPU capacity asymmetry bits
  sched/topology: Rework CPU capacity asymmetry detection
  sched/core: Introduce SD_ASYM_CPUCAPACITY_FULL sched_domain flag
  psi: Fix race between psi_trigger_create/destroy
  sched/fair: Introduce the burstable CFS controller
  sched/uclamp: Fix uclamp_tg_restrict()
  sched/rt: Fix Deadline utilization tracking during policy change
  sched/rt: Fix RT utilization tracking during policy change
  sched: Change task_struct::state
  sched,arch: Remove unused TASK_STATE offsets
  sched,timer: Use __set_current_state()
  sched: Add get_current_state()
  sched,perf,kvm: Fix preemption condition
  sched: Introduce task_is_running()
  sched: Unbreak wakeups
  sched/fair: Age the average idle time
  sched/cpufreq: Consider reduced CPU capacity in energy calculation
  sched/fair: Take thermal pressure into account while estimating energy
  thermal/cpufreq_cooling: Update offline CPUs per-cpu thermal_pressure
  sched/fair: Return early from update_tg_cfs_load() if delta == 0
  ...
2021-06-28 12:14:19 -07:00
Peter Zijlstra
b03fbd4ff2 sched: Introduce task_is_running()
Replace a bunch of 'p->state == TASK_RUNNING' with a new helper:
task_is_running(p).

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Davidlohr Bueso <dave@stgolabs.net>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20210611082838.222401495@infradead.org
2021-06-18 11:43:07 +02:00
Guenter Roeck
33f087577e ARM: 9096/1: Remove arm_pm_restart()
All users of arm_pm_restart() have been converted to use the kernel
restart handler.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-13 18:16:48 +01:00
Guenter Roeck
ce8f1ccbc0 ARM: 9094/1: Register with kernel restart handler
By making use of the kernel restart handler, board specific restart
handlers can be prioritized amongst available mechanisms for a particular
board or system.

Select the default priority of 128 to indicate that the restart callback
in the machine description is the default restart mechanism.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-13 18:16:46 +01:00
Linus Walleij
a91da54570 ARM: 9089/1: Define kernel physical section start and end
When we are mapping the initial sections in head.S we
know very well where the start and end of the kernel image
in physical memory is placed. Later on it gets hard
to determine this.

Save the information into two variables named
kernel_sec_start and kernel_sec_end for convenience
for later work involving the physical start and end
of the kernel. These variables are section-aligned
corresponding to the early section mappings set up
in head.S.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-13 18:16:41 +01:00
Linus Walleij
b78f63f443 ARM: 9088/1: Split KERNEL_OFFSET from PAGE_OFFSET
We want to be able to compile the kernel into an address different
from PAGE_OFFSET (start of lowmem) + TEXT_OFFSET, so start to pry
apart the address of where the kernel is located from the address
where the lowmem is located by defining and using KERNEL_OFFSET in
a few key places.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-13 18:16:40 +01:00
Marc Zyngier
e1c054918c genirq: Move non-irqdomain handle_domain_irq() handling into ARM's handle_IRQ()
Despite the name, handle_domain_irq() deals with non-irqdomain
handling for the sake of a handful of legacy ARM platforms.

Move such handling into ARM's handle_IRQ(), allowing for better
code generation for everyone else. This allows us get rid of
some complexity, and to rearrange the guards on the various helpers
in a more logical way.

Signed-off-by: Marc Zyngier <maz@kernel.org>
2021-06-10 13:09:19 +01:00
Alex Sverdlin
79f32b221b ARM: 9079/1: ftrace: Add MODULE_PLTS support
Teach ftrace_make_call() and ftrace_make_nop() about PLTs.
Teach PLT code about FTRACE and all its callbacks.
Otherwise the following might happen:

------------[ cut here ]------------
WARNING: CPU: 14 PID: 2265 at .../arch/arm/kernel/insn.c:14 __arm_gen_branch+0x83/0x8c()
...
Hardware name: LSI Axxia AXM55XX
[<c0314a49>] (unwind_backtrace) from [<c03115e9>] (show_stack+0x11/0x14)
[<c03115e9>] (show_stack) from [<c0519f51>] (dump_stack+0x81/0xa8)
[<c0519f51>] (dump_stack) from [<c032185d>] (warn_slowpath_common+0x69/0x90)
[<c032185d>] (warn_slowpath_common) from [<c03218f3>] (warn_slowpath_null+0x17/0x1c)
[<c03218f3>] (warn_slowpath_null) from [<c03143cf>] (__arm_gen_branch+0x83/0x8c)
[<c03143cf>] (__arm_gen_branch) from [<c0314337>] (ftrace_make_nop+0xf/0x24)
[<c0314337>] (ftrace_make_nop) from [<c038ebcb>] (ftrace_process_locs+0x27b/0x3e8)
[<c038ebcb>] (ftrace_process_locs) from [<c0378d79>] (load_module+0x11e9/0x1a44)
[<c0378d79>] (load_module) from [<c037974d>] (SyS_finit_module+0x59/0x84)
[<c037974d>] (SyS_finit_module) from [<c030e981>] (ret_fast_syscall+0x1/0x18)
---[ end trace e1b64ced7a89adcc ]---
------------[ cut here ]------------
WARNING: CPU: 14 PID: 2265 at .../kernel/trace/ftrace.c:1979 ftrace_bug+0x1b1/0x234()
...
Hardware name: LSI Axxia AXM55XX
[<c0314a49>] (unwind_backtrace) from [<c03115e9>] (show_stack+0x11/0x14)
[<c03115e9>] (show_stack) from [<c0519f51>] (dump_stack+0x81/0xa8)
[<c0519f51>] (dump_stack) from [<c032185d>] (warn_slowpath_common+0x69/0x90)
[<c032185d>] (warn_slowpath_common) from [<c03218f3>] (warn_slowpath_null+0x17/0x1c)
[<c03218f3>] (warn_slowpath_null) from [<c038e87d>] (ftrace_bug+0x1b1/0x234)
[<c038e87d>] (ftrace_bug) from [<c038ebd5>] (ftrace_process_locs+0x285/0x3e8)
[<c038ebd5>] (ftrace_process_locs) from [<c0378d79>] (load_module+0x11e9/0x1a44)
[<c0378d79>] (load_module) from [<c037974d>] (SyS_finit_module+0x59/0x84)
[<c037974d>] (SyS_finit_module) from [<c030e981>] (ret_fast_syscall+0x1/0x18)
---[ end trace e1b64ced7a89adcd ]---
ftrace failed to modify [<e9ef7006>] 0xe9ef7006
actual: 02:f0:3b:fa
ftrace record flags: 0
(0) expected tramp: c0314265

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-07 12:56:20 +01:00
Alex Sverdlin
890cb057a4 ARM: 9078/1: Add warn suppress parameter to arm_gen_branch_link()
Will be used in the following patch. No functional change.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-07 12:56:20 +01:00
Alex Sverdlin
4e271701c1 ARM: 9077/1: PLT: Move struct plt_entries definition to header
No functional change, later it will be re-used in several files.

Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-07 12:56:20 +01:00
Arnd Bergmann
dad7b9896a ARM: 9081/1: fix gcc-10 thumb2-kernel regression
When building the kernel wtih gcc-10 or higher using the
CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE=y flag, the compiler picks a slightly
different set of registers for the inline assembly in cpu_init() that
subsequently results in a corrupt kernel stack as well as remaining in
FIQ mode. If a banked register is used for the last argument, the wrong
version of that register gets loaded into CPSR_c.  When building in Arm
mode, the arguments are passed as immediate values and the bug cannot
happen.

This got introduced when Daniel reworked the FIQ handling and was
technically always broken, but happened to work with both clang and gcc
before gcc-10 as long as they picked one of the lower registers.
This is probably an indication that still very few people build the
kernel in Thumb2 mode.

Marek pointed out the problem on IRC, Arnd narrowed it down to this
inline assembly and Russell pinpointed the exact bug.

Change the constraints to force the final mode switch to use a non-banked
register for the argument to ensure that the correct constant gets loaded.
Another alternative would be to always use registers for the constant
arguments to avoid the #ifdef that has now become more complex.

Cc: <stable@vger.kernel.org> # v3.18+
Cc: Daniel Thompson <daniel.thompson@linaro.org>
Reported-by: Marek Vasut <marek.vasut@gmail.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Fixes: c0e7f7ee71 ("ARM: 8150/3: fiq: Replace default FIQ handler")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-06-03 11:39:36 +01:00
Yang Jihong
fdbef8c4e6 arm_pmu: Fix write counter incorrect in ARMv7 big-endian mode
Commit 3a95200d3f ("arm_pmu: Change API to support 64bit counter values")
changes the input "value" type from 32-bit to 64-bit, which introduces the
following problem: ARMv7 PMU counters is 32-bit width, in big-endian mode,
write counter uses high 32-bit, which writes an incorrect value.

Before:

 Performance counter stats for 'ls':

              2.22 msec task-clock                #    0.675 CPUs utilized
                 0      context-switches          #    0.000 K/sec
                 0      cpu-migrations            #    0.000 K/sec
                49      page-faults               #    0.022 M/sec
        2150476593      cycles                    #  966.663 GHz
        2148588788      instructions              #    1.00  insn per cycle
        2147745484      branches                  # 965435.074 M/sec
        2147508540      branch-misses             #   99.99% of all branches

None of the above hw event counters are correct.

Solution:

"value" forcibly converted to 32-bit type before being written to PMU register.

After:

 Performance counter stats for 'ls':

              2.09 msec task-clock                #    0.681 CPUs utilized
                 0      context-switches          #    0.000 K/sec
                 0      cpu-migrations            #    0.000 K/sec
                46      page-faults               #    0.022 M/sec
           2807301      cycles                    #    1.344 GHz
           1060159      instructions              #    0.38  insn per cycle
            250496      branches                  #  119.914 M/sec
             23192      branch-misses             #    9.26% of all branches

Fixes: 3a95200d3f ("arm_pmu: Change API to support 64bit counter values")
Cc: <stable@vger.kernel.org>
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20210430012659.232110-1-yangjihong1@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-01 14:17:01 +01:00
Valentin Schneider
f1a0a376ca sched/core: Initialize the idle task with preemption disabled
As pointed out by commit

  de9b8f5dcb ("sched: Fix crash trying to dequeue/enqueue the idle thread")

init_idle() can and will be invoked more than once on the same idle
task. At boot time, it is invoked for the boot CPU thread by
sched_init(). Then smp_init() creates the threads for all the secondary
CPUs and invokes init_idle() on them.

As the hotplug machinery brings the secondaries to life, it will issue
calls to idle_thread_get(), which itself invokes init_idle() yet again.
In this case it's invoked twice more per secondary: at _cpu_up(), and at
bringup_cpu().

Given smp_init() already initializes the idle tasks for all *possible*
CPUs, no further initialization should be required. Now, removing
init_idle() from idle_thread_get() exposes some interesting expectations
with regards to the idle task's preempt_count: the secondary startup always
issues a preempt_disable(), requiring some reset of the preempt count to 0
between hot-unplug and hotplug, which is currently served by
idle_thread_get() -> idle_init().

Given the idle task is supposed to have preemption disabled once and never
see it re-enabled, it seems that what we actually want is to initialize its
preempt_count to PREEMPT_DISABLED and leave it there. Do that, and remove
init_idle() from idle_thread_get().

Secondary startups were patched via coccinelle:

  @begone@
  @@

  -preempt_disable();
  ...
  cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);

Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20210512094636.2958515-1-valentin.schneider@arm.com
2021-05-12 13:01:45 +02:00
Linus Torvalds
a48b0872e6 Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:
 "This is everything else from -mm for this merge window.

  90 patches.

  Subsystems affected by this patch series: mm (cleanups and slub),
  alpha, procfs, sysctl, misc, core-kernel, bitmap, lib, compat,
  checkpatch, epoll, isofs, nilfs2, hpfs, exit, fork, kexec, gcov,
  panic, delayacct, gdb, resource, selftests, async, initramfs, ipc,
  drivers/char, and spelling"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (90 commits)
  mm: fix typos in comments
  mm: fix typos in comments
  treewide: remove editor modelines and cruft
  ipc/sem.c: spelling fix
  fs: fat: fix spelling typo of values
  kernel/sys.c: fix typo
  kernel/up.c: fix typo
  kernel/user_namespace.c: fix typos
  kernel/umh.c: fix some spelling mistakes
  include/linux/pgtable.h: few spelling fixes
  mm/slab.c: fix spelling mistake "disired" -> "desired"
  scripts/spelling.txt: add "overflw"
  scripts/spelling.txt: Add "diabled" typo
  scripts/spelling.txt: add "overlfow"
  arm: print alloc free paths for address in registers
  mm/vmalloc: remove vwrite()
  mm: remove xlate_dev_kmem_ptr()
  drivers/char: remove /dev/kmem for good
  mm: fix some typos and code style problems
  ipc/sem.c: mundane typo fixes
  ...
2021-05-07 00:34:51 -07:00
Maninder Singh
5aa6b70ed1 arm: print alloc free paths for address in registers
In case of a use after free kernel oops, the freeing path of the object
is required to debug futher.  In most of cases the object address is
present in one of the registers.

Thus check the register's address and if it belongs to slab, print its
alloc and free path.

e.g. in the below issue register r6 belongs to slab, and a use after
free issue occurred on one of its dereferenced values:

  Unable to handle kernel paging request at virtual address 6b6b6b6f
  ....
  pc : [<c0538afc>]    lr : [<c0465674>]    psr: 60000013
  sp : c8927d40  ip : ffffefff  fp : c8aa8020
  r10: c8927e10  r9 : 00000001  r8 : 00400cc0
  r7 : 00000000  r6 : c8ab0180  r5 : c1804a80  r4 : c8aa8008
  r3 : c1a5661c  r2 : 00000000  r1 : 6b6b6b6b  r0 : c139bf48
  .....
  Register r6 information: slab kmalloc-64 start c8ab0140 data offset 64 pointer offset 0 size 64 allocated at meminfo_proc_show+0x40/0x4fc
      meminfo_proc_show+0x40/0x4fc
      seq_read_iter+0x18c/0x4c4
      proc_reg_read_iter+0x84/0xac
      generic_file_splice_read+0xe8/0x17c
      splice_direct_to_actor+0xb8/0x290
      do_splice_direct+0xa0/0xe0
      do_sendfile+0x2d0/0x438
      sys_sendfile64+0x12c/0x140
      ret_fast_syscall+0x0/0x58
      0xbeeacde4
   Free path:
      meminfo_proc_show+0x5c/0x4fc
      seq_read_iter+0x18c/0x4c4
      proc_reg_read_iter+0x84/0xac
      generic_file_splice_read+0xe8/0x17c
      splice_direct_to_actor+0xb8/0x290
      do_splice_direct+0xa0/0xe0
      do_sendfile+0x2d0/0x438
      sys_sendfile64+0x12c/0x140
      ret_fast_syscall+0x0/0x58
      0xbeeacde4

Link: https://lkml.kernel.org/r/1615891032-29160-3-git-send-email-maninder1.s@samsung.com
Co-developed-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07 00:26:34 -07:00
Linus Torvalds
322a3b843d Merge tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm
Pull ARM updates from Russell King:

 - Fix BSS size calculation for LLVM

 - Improve robustness of kernel entry around v7_invalidate_l1

 - Fix and update kprobes assembly

 - Correct breakpoint overflow handler check

 - Pause function graph tracer when suspending a CPU

 - Switch to generic syscallhdr.sh and syscalltbl.sh

 - Remove now unused set_kernel_text_r[wo] functions

 - Updates for ptdump (__init marking and using DEFINE_SHOW_ATTRIBUTE)

 - Fix for interrupted SMC (secure) calls

 - Remove Compaq Personal Server platform

* tag 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: footbridge: remove personal server platform
  ARM: 9075/1: kernel: Fix interrupted SMC calls
  ARM: 9074/1: ptdump: convert to DEFINE_SHOW_ATTRIBUTE
  ARM: 9073/1: ptdump: add __init section marker to three functions
  ARM: 9072/1: mm: remove set_kernel_text_r[ow]()
  ARM: 9067/1: syscalls: switch to generic syscallhdr.sh
  ARM: 9068/1: syscalls: switch to generic syscalltbl.sh
  ARM: 9066/1: ftrace: pause/unpause function graph tracer in cpu_suspend()
  ARM: 9064/1: hw_breakpoint: Do not directly check the event's overflow_handler hook
  ARM: 9062/1: kprobes: rewrite test-arm.c in UAL
  ARM: 9061/1: kprobes: fix UNPREDICTABLE warnings
  ARM: 9060/1: kexec: Remove unused kexec_reinit callback
  ARM: 9059/1: cache-v7: get rid of mini-stack
  ARM: 9058/1: cache-v7: refactor v7_invalidate_l1 to avoid clobbering r5/r6
  ARM: 9057/1: cache-v7: add missing ISB after cache level selection
  ARM: 9056/1: decompressor: fix BSS size calculation for LLVM ld.lld
2021-05-06 09:28:07 -07:00
Manivannan Sadhasivam
57ac51667d ARM: 9075/1: kernel: Fix interrupted SMC calls
On Qualcomm ARM32 platforms, the SMC call can return before it has
completed. If this occurs, the call can be restarted, but it requires
using the returned session ID value from the interrupted SMC call.

The ARM32 SMCC code already has the provision to add platform specific
quirks for things like this. So let's make use of it and add the
Qualcomm specific quirk (ARM_SMCCC_QUIRK_QCOM_A6) used by the QCOM_SCM
driver.

This change is similar to the below one added for ARM64 a while ago:
commit 82bcd08702 ("firmware: qcom: scm: Fix interrupted SCM calls")

Without this change, the Qualcomm ARM32 platforms like SDX55 will return
-EINVAL for SMC calls used for modem firmware loading and validation.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-04-18 19:15:14 +01:00
Masahiro Yamada
0047eb9f09 ARM: 9068/1: syscalls: switch to generic syscalltbl.sh
Many architectures duplicate similar shell scripts.

This commit converts ARM to use scripts/syscalltbl.sh.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-03-25 14:13:13 +00:00
louis.wang
8252ca87c7 ARM: 9066/1: ftrace: pause/unpause function graph tracer in cpu_suspend()
Enabling function_graph tracer on ARM causes kernel panic, because the
function graph tracer updates the "return address" of a function in order
to insert a trace callback on function exit, it saves the function's
original return address in a return trace stack, but cpu_suspend() may not
return through the normal return path.

cpu_suspend() will resume directly via the cpu_resume path, but the return
trace stack has been set-up by the subfunctions of cpu_suspend(), which
makes the "return address" inconsistent with cpu_suspend().

This patch refers to Commit de818bd452
("arm64: kernel: pause/unpause function graph tracer in cpu_suspend()"),

fixes the issue by pausing/resuming the function graph tracer on the thread
executing cpu_suspend(), so that the function graph tracer state is kept
consistent across functions that enter power down states and never return
by effectively disabling graph tracer while they are executing.

Signed-off-by: louis.wang <liang26812@gmail.com>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-03-25 10:27:42 +00:00
Zhen Lei
a506bd5756 ARM: 9064/1: hw_breakpoint: Do not directly check the event's overflow_handler hook
The commit 1879445dfa ("perf/core: Set event's default
::overflow_handler()") set a default event->overflow_handler in
perf_event_alloc(), and replace the check event->overflow_handler with
is_default_overflow_handler(), but one is missing.

Currently, the bp->overflow_handler can not be NULL. As a result,
enable_single_step() is always not invoked.

Comments from Zhen Lei:

 https://patchwork.kernel.org/project/linux-arm-kernel/patch/20210207105934.2001-1-thunder.leizhen@huawei.com/

Fixes: 1879445dfa ("perf/core: Set event's default ::overflow_handler()")
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Cc: Wang Nan <wangnan0@huawei.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2021-03-25 10:27:41 +00:00