Commit Graph

335 Commits

Author SHA1 Message Date
Atish Patra
2875fe0561 RISC-V: Add cpu_ops and modify default booting method
Currently, all non-booting harts start booting after the booting hart
updates the per-hart stack pointer. This is done in a way that, it's
difficult to implement any other booting method without breaking the
backward compatibility.

Define a cpu_ops method that allows to introduce other booting methods
in future. Modify the current booting method to be compatible with
cpu_ops.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31 11:25:56 -07:00
Atish Patra
e011995e82 RISC-V: Move relocate and few other functions out of __init
The secondary hart booting and relocation code are under .init section.
As a result, it will be freed once kernel booting is done. However,
ordered booting protocol and CPU hotplug always requires these functions
to be present to bringup harts after initial kernel boot.

Move the required functions to a different section and make sure that
they are in memory within first 2MB offset as trampoline page directory
only maps first 2MB.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31 11:25:50 -07:00
Atish Patra
1ef46c231d RISC-V: Implement new SBI v0.2 extensions
Few v0.1 SBI calls are being replaced by new SBI calls that follows v0.2
calling convention.

Implement the replacement extensions and few additional new SBI function calls
that makes way for a better SBI interface in future.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31 11:25:45 -07:00
Atish Patra
efca139892 RISC-V: Introduce a new config for SBI v0.1
We now have SBI v0.2 which is more scalable and extendable to handle
future needs for RISC-V supervisor interfaces.

Introduce a new config and move all SBI v0.1 code under that config.
This allows to implement the new replacement SBI extensions cleanly
and remove v0.1 extensions easily in future. Currently, the config
is enabled by default. Once all M-mode software, with v0.1, is no
longer in use, this config option and all relevant code can be easily
removed.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31 11:25:40 -07:00
Atish Patra
b9dcd9e415 RISC-V: Add basic support for SBI v0.2
The SBI v0.2 introduces a base extension which is backward compatible
with v0.1. Implement all helper functions and minimum required SBI
calls from v0.2 for now. All other base extension function will be
added later as per need.
As v0.2 calling convention is backward compatible with v0.1, remove
the v0.1 helper functions and just use v0.2 calling convention.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-31 11:25:29 -07:00
Linus Torvalds
2d385336af Merge tag 'irq-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "Updates for the interrupt subsystem:

  Treewide:

    - Cleanup of setup_irq() which is not longer required because the
      memory allocator is available early.

      Most cleanup changes come through the various maintainer trees, so
      the final removal of setup_irq() is postponed towards the end of
      the merge window.

  Core:

    - Protection against unsafe invocation of interrupt handlers and
      unsafe interrupt injection including a fixup of the offending
      PCI/AER error injection mechanism.

      Invoking interrupt handlers from arbitrary contexts, i.e. outside
      of an actual interrupt, can cause inconsistent state on the
      fragile x86 interrupt affinity changing hardware trainwreck.

  Drivers:

    - Second wave of support for the new ARM GICv4.1

    - Multi-instance support for Xilinx and PLIC interrupt controllers

    - CPU-Hotplug support for PLIC

    - The obligatory new driver for X1000 TCU

    - Enhancements, cleanups and fixes all over the place"

* tag 'irq-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  unicore32: Replace setup_irq() by request_irq()
  sh: Replace setup_irq() by request_irq()
  hexagon: Replace setup_irq() by request_irq()
  c6x: Replace setup_irq() by request_irq()
  alpha: Replace setup_irq() by request_irq()
  irqchip/gic-v4.1: Eagerly vmap vPEs
  irqchip/gic-v4.1: Add VSGI property setup
  irqchip/gic-v4.1: Add VSGI allocation/teardown
  irqchip/gic-v4.1: Move doorbell management to the GICv4 abstraction layer
  irqchip/gic-v4.1: Plumb set_vcpu_affinity SGI callbacks
  irqchip/gic-v4.1: Plumb get/set_irqchip_state SGI callbacks
  irqchip/gic-v4.1: Plumb mask/unmask SGI callbacks
  irqchip/gic-v4.1: Add initial SGI configuration
  irqchip/gic-v4.1: Plumb skeletal VSGI irqchip
  irqchip/stm32: Retrigger both in eoi and unmask callbacks
  irqchip/gic-v3: Move irq_domain_update_bus_token to after checking for NULL domain
  irqchip/xilinx: Do not call irq_set_default_host()
  irqchip/xilinx: Enable generic irq multi handler
  irqchip/xilinx: Fill error code when irq domain registration fails
  irqchip/xilinx: Add support for multiple instances
  ...
2020-03-30 17:35:14 -07:00
Zong Li
8fdddb2eae riscv: patch code by fixmap mapping
On strict kernel memory permission, the ftrace have to change the
permission of text for dynamic patching the intructions. Use
riscv_patch_text_nosync() to patch code instead of probe_kernel_write.

Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26 09:24:55 -07:00
Zong Li
043cb41a85 riscv: introduce interfaces to patch kernel code
On strict kernel memory permission, we couldn't patch code without
writable permission. Preserve two holes in fixmap area, so we can map
the kernel code temporarily to fixmap area, then patch the instructions.

We need two pages here because we support the compressed instruction, so
the instruction might be align to 2 bytes. When patching the 32-bit
length instruction which is 2 bytes alignment, it will across two pages.

Introduce two interfaces to patch kernel code:
riscv_patch_text_nosync:
 - patch code without synchronization, it's caller's responsibility to
   synchronize all CPUs if needed.
riscv_patch_text:
 - patch code and always synchronize with stop_machine()

Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26 09:24:52 -07:00
Zong Li
b42d763a2d riscv: add macro to get instruction length
Extract the calculation of instruction length for common use.

Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26 09:24:49 -07:00
Zong Li
00cb41d5ad riscv: add alignment for text, rodata and data sections
The kernel mapping will tried to optimize its mapping by using bigger
size. In rv64, it tries to use PMD_SIZE, and tryies to use PGDIR_SIZE in
rv32. To ensure that the start address of these sections could fit the
mapping entry size, make them align to the biggest alignment.

Define a macro SECTION_ALIGN because the HPAGE_SIZE or PMD_SIZE, etc.,
are invisible in linker script.

This patch is prepared for STRICT_KERNEL_RWX support.

Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26 09:24:42 -07:00
Zong Li
bd3d914d16 riscv: move exception table immediately after RO_DATA
Move EXCEPTION_TABLE immediately after RO_DATA. Make it easy to set the
attribution of the sections which should be read-only at a time.
Add _data to specify the start of data section with write permission.
This patch is prepared for STRICT_KERNEL_RWX support.

Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-26 09:24:39 -07:00
Masahiro Yamada
d198b34f38 .gitignore: add SPDX License Identifier
Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-25 11:50:48 +01:00
Greentime Hu
3384b043ea riscv: fix the IPI missing issue in nommu mode
This patch fixes the IPI(inner processor interrupt) missing issue. It
failed because it used hartid_mask to iterate for_each_cpu(), however the
cpu_mask and hartid_mask may not be always the same. It will never send the
IPI to hartid 4 because it will be skipped in for_each_cpu loop in my case.

We can reproduce this case in Qemu sifive_u machine by this command.
qemu-system-riscv64 -nographic -smp 5 -m 1G -M sifive_u -kernel \
arch/riscv/boot/loader

It will hang in csd_lock_wait(csd) because the csd_unlock(csd) is not
called. It is not called because hartid 4 doesn't receive the IPI to
release this lock. The caller hart doesn't send the IPI to hartid 4 is
because of hartid 4 is skipped in for_each_cpu(). It will be skipped is
because "(cpu) < nr_cpu_ids" is not true. The hartid is 4 and nr_cpu_ids
is 4. Therefore it should use cpumask in for_each_cpu() instead of
hartid_mask.

        /* Send a message to all CPUs in the map */
        arch_send_call_function_ipi_mask(cfd->cpumask_ipi);

        if (wait) {
                for_each_cpu(cpu, cfd->cpumask) {
                        call_single_data_t *csd;
			csd = per_cpu_ptr(cfd->csd, cpu);
                        csd_lock_wait(csd);
                }
        }

        for ((cpu) = -1;                                \
                (cpu) = cpumask_next((cpu), (mask)),    \
                (cpu) < nr_cpu_ids;)

It could boot to login console after this patch applied.

Fixes: b2d36b5668f6 ("riscv: provide native clint access for M-mode")
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-18 18:44:39 -07:00
Atish Patra
ccbe80bad5 irqchip/sifive-plic: Enable/Disable external interrupts upon cpu online/offline
Currently, PLIC threshold is only initialized once in the beginning.
However, threshold can be set to disabled if a CPU is marked offline with
CPU hotplug feature. This will not allow to change the irq affinity to a
CPU that just came online.

Add PLIC specific CPU hotplug callbacks and enable the threshold when a CPU
comes online. Take this opportunity to move the external interrupt enable
code from trap init to PLIC driver as well. On cpu offline path, the driver
performs the exact opposite operations i.e. disable the interrupt and
the threshold.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20200302231146.15530-2-atish.patra@wdc.com
2020-03-16 15:48:54 +00:00
Tycho Andersen
af33d2433b riscv: fix seccomp reject syscall code path
If secure_computing() rejected a system call, we were previously setting
the system call number to -1, to indicate to later code that the syscall
failed. However, if something (e.g. a user notification) was sleeping, and
received a signal, we may set a0 to -ERESTARTSYS and re-try the system call
again.

In this case, seccomp "denies" the syscall (because of the signal), and we
would set a7 to -1, thus losing the value of the system call we want to
restart.

Instead, let's return -1 from do_syscall_trace_enter() to indicate that the
syscall was rejected, so we don't clobber the value in case of -ERESTARTSYS
or whatever.

This commit fixes the user_notification_signal seccomp selftest on riscv to
no longer hang. That test expects the system call to be re-issued after the
signal, and it wasn't due to the above bug. Now that it is, everything
works normally.

Note that in the ptrace (tracer) case, the tracer can set the register
values to whatever they want, so we still need to keep the code that
handles out-of-bounds syscalls. However, we can drop the comment.

We can also drop syscall_set_nr(), since it is no longer used anywhere, and
the code that re-loads the value in a7 because of it.

Reported in: https://lore.kernel.org/bpf/CAEn-LTp=ss0Dfv6J00=rCAy+N78U2AmhqJNjfqjr2FDpPYjxEQ@mail.gmail.com/

Reported-by: David Abdurachmanov <david.abdurachmanov@gmail.com>
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-05 13:58:15 -08:00
Palmer Dabbelt
fdff9911f2 RISC-V: Inline the assembly register save/restore macros
These are only used once, and when reading the code I've always found them to
be more of a headache than a benefit.  While they were never worth removing
before, LLVM's integrated assembler doesn't support LOCAL so rather that trying
to figure out how to refactor the macros it seems saner to just inline them.

Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03 10:33:21 -08:00
Palmer Dabbelt
52e7c52d2d RISC-V: Stop relying on GCC's register allocator's hueristics
GCC allows users to hint to the register allocation that a variable should be
placed in a register by using a syntax along the lines of

    function(...) {
        register long in_REG __asm__("REG");
    }

We've abused this a bit throughout the RISC-V port to access fixed registers
directly as C variables.  In practice it's never going to blow up because GCC
isn't going to allocate these registers, but it's not a well defined syntax so
we really shouldn't be relying upon this.  Luckily there is a very similar but
well defined syntax that allows us to still access these registers directly as
C variables, which is to simply declare the register variables globally.  For
fixed variables this doesn't change the ABI.

LLVM disallows this ambiguous syntax, so this isn't just strictly a formatting
change.

Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03 10:28:13 -08:00
Palmer Dabbelt
064223b947 RISC-V: Stop putting .sbss in .sdata
I don't know why we were doing this, as it's been there since the beginning.
After d841f729e655 ("riscv: force hart_lottery to put in .sdata section") my
guess would be that it made the kernel boot and we forgot to fix it more
cleanly.

The default .bss segment already contains the .sbss section, so we don't need
to do anything additional to ensure the symbols in .sbss continue to work.

Tested-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03 10:28:12 -08:00
Zong Li
aff7783392 riscv: force hart_lottery to put in .sdata section
In PIC code model, the zero initialized data always be put in .bss
section, so when building kernel as PIE, the hart_lottery won't present
in small data section, and it causes more than one harts to get the
lottery, because the main hart clears the content of .bss section
immediately after it getting the lottery.

Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
[Palmer: added a comment]
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03 10:28:11 -08:00
Vincent Chen
0cff8bff7a riscv: avoid the PIC offset of static percpu data in module beyond 2G limits
The compiler uses the PIC-relative method to access static variables
instead of GOT when the code model is PIC. Therefore, the limitation of
the access range from the instruction to the symbol address is +-2GB.
Under this circumstance, the kernel cannot load a kernel module if this
module has static per-CPU symbols declared by DEFINE_PER_CPU(). The reason
is that kernel relocates the .data..percpu section of the kernel module to
the end of kernel's .data..percpu. Hence, the distance between the per-CPU
symbols and the instruction will exceed the 2GB limits. To solve this
problem, the kernel should place the loaded module in the memory area
[&_end-2G, VMALLOC_END].

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Suggested-by: Alexandre Ghiti <alex@ghiti.fr>
Suggested-by: Anup Patel <anup@brainfault.org>
Tested-by: Alexandre Ghiti <alex@ghiti.fr>
Tested-by: Carlos de Paula <me@carlosedp.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-03-03 10:27:45 -08:00
Anup Patel
6a1ce99dc4 RISC-V: Don't enable all interrupts in trap_init()
Historically, we have been enabling all interrupts for each
HART in trap_init(). Ideally, we should only enable M-mode
interrupts for M-mode kernel and S-mode interrupts for S-mode
kernel in trap_init().

Currently, we get suprious S-mode interrupts on Kendryte K210
board running M-mode NO-MMU kernel because we are enabling all
interrupts in trap_init(). To fix this, we only enable software
and external interrupt in trap_init(). In future, trap_init()
will only enable software interrupt and PLIC driver will enable
external interrupt using CPU notifiers.

Fixes: a4c3733d32 ("riscv: abstract out CSR names for supervisor vs machine mode")
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Palmer Dabbelt <palmerdabbelt@google.com> [QMEU virt machine with SMP]
[Palmer: Move the Fixes up to a newer commit]
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-18 10:34:04 -08:00
Greentime Hu
c68a903229 riscv: set pmp configuration if kernel is running in M-mode
When the kernel is running in S-mode, the expectation is that the
bootloader or SBI layer will configure the PMP to allow the kernel to
access physical memory.  But, when the kernel is running in M-mode and is
started with the ELF "loader", there's probably no bootloader or SBI layer
involved to configure the PMP.  Thus, we need to configure the PMP
ourselves to enable the kernel to access all regions.

Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-02-18 09:41:24 -08:00
Linus Torvalds
a1084542a8 Merge tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
 "This contains a handful of patches for this merge window:

   - Support for kasan

   - 32-bit physical addresses on rv32i-based systems

   - Support for CONFIG_DEBUG_VIRTUAL

   - DT entry for the FU540 GPIO controller, which has recently had a
     device driver merged

  These boot a buildroot-based system on QEMU's virt board for me"

* tag 'riscv-for-linus-5.6-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: dts: Add DT support for SiFive FU540 GPIO driver
  riscv: mm: add support for CONFIG_DEBUG_VIRTUAL
  riscv: keep 32-bit kernel to 32-bit phys_addr_t
  kasan: Add riscv to KASAN documentation.
  riscv: Add KASAN support
  kasan: No KASAN's memmove check if archs don't have it.
2020-01-31 11:23:29 -08:00
Linus Torvalds
ca9b5b6283 Merge tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty
Pull tty/serial driver updates from Greg KH:
 "Here are the big set of tty and serial driver updates for 5.6-rc1

  Included in here are:
   - dummy_con cleanups (touches lots of arch code)
   - sysrq logic cleanups (touches lots of serial drivers)
   - samsung driver fixes (wasn't really being built)
   - conmakeshash move to tty subdir out of scripts
   - lots of small tty/serial driver updates

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'tty-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (140 commits)
  tty: n_hdlc: Use flexible-array member and struct_size() helper
  tty: baudrate: SPARC supports few more baud rates
  tty: baudrate: Synchronise baud_table[] and baud_bits[]
  tty: serial: meson_uart: Add support for kernel debugger
  serial: imx: fix a race condition in receive path
  serial: 8250_bcm2835aux: Document struct bcm2835aux_data
  serial: 8250_bcm2835aux: Use generic remapping code
  serial: 8250_bcm2835aux: Allocate uart_8250_port on stack
  serial: 8250_bcm2835aux: Suppress register_port error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Suppress clk_get error on -EPROBE_DEFER
  serial: 8250_bcm2835aux: Fix line mismatch on driver unbind
  serial_core: Remove unused member in uart_port
  vt: Correct comment documenting do_take_over_console()
  vt: Delete comment referencing non-existent unbind_con_driver()
  arch/xtensa/setup: Drop dummy_con initialization
  arch/x86/setup: Drop dummy_con initialization
  arch/unicore32/setup: Drop dummy_con initialization
  arch/sparc/setup: Drop dummy_con initialization
  arch/sh/setup: Drop dummy_con initialization
  arch/s390/setup: Drop dummy_con initialization
  ...
2020-01-29 10:13:27 -08:00
Linus Torvalds
c677124e63 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "These were the main changes in this cycle:

   - More -rt motivated separation of CONFIG_PREEMPT and
     CONFIG_PREEMPTION.

   - Add more low level scheduling topology sanity checks and warnings
     to filter out nonsensical topologies that break scheduling.

   - Extend uclamp constraints to influence wakeup CPU placement

   - Make the RT scheduler more aware of asymmetric topologies and CPU
     capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y

   - Make idle CPU selection more consistent

   - Various fixes, smaller cleanups, updates and enhancements - please
     see the git log for details"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
  sched/fair: Define sched_idle_cpu() only for SMP configurations
  sched/topology: Assert non-NUMA topology masks don't (partially) overlap
  idle: fix spelling mistake "iterrupts" -> "interrupts"
  sched/fair: Remove redundant call to cpufreq_update_util()
  sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled
  sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP
  sched/fair: calculate delta runnable load only when it's needed
  sched/cputime: move rq parameter in irqtime_account_process_tick
  stop_machine: Make stop_cpus() static
  sched/debug: Reset watchdog on all CPUs while processing sysrq-t
  sched/core: Fix size of rq::uclamp initialization
  sched/uclamp: Fix a bug in propagating uclamp value in new cgroups
  sched/fair: Load balance aggressively for SCHED_IDLE CPUs
  sched/fair : Improve update_sd_pick_busiest for spare capacity case
  watchdog: Remove soft_lockup_hrtimer_cnt and related code
  sched/rt: Make RT capacity-aware
  sched/fair: Make EAS wakeup placement consider uclamp restrictions
  sched/fair: Make task_fits_capacity() consider uclamp restrictions
  sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with()
  sched/uclamp: Make uclamp util helpers use and return UL values
  ...
2020-01-28 10:07:09 -08:00
Nick Hu
8ad8b72721 riscv: Add KASAN support
This patch ports the feature Kernel Address SANitizer (KASAN).

Note: The start address of shadow memory is at the beginning of kernel
space, which is 2^64 - (2^39 / 2) in SV39. The size of the kernel space is
2^38 bytes so the size of shadow memory should be 2^38 / 8. Thus, the
shadow memory would not overlap with the fixmap area.

There are currently two limitations in this port,

1. RV64 only: KASAN need large address space for extra shadow memory
region.

2. KASAN can't debug the modules since the modules are allocated in VMALLOC
area. We mapped the shadow memory, which corresponding to VMALLOC area, to
the kasan_early_shadow_page because we don't have enough physical space for
all the shadow memory corresponding to VMALLOC area.

Signed-off-by: Nick Hu <nickhu@andestech.com>
Reported-by: Greentime Hu <green.hu@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2020-01-22 13:09:58 -08:00
Ilie Halip
95f4d9cced riscv: delete temporary files
Temporary files used in the VDSO build process linger on even after make
mrproper: vdso-dummy.o.tmp, vdso.so.dbg.tmp.

Delete them once they're no longer needed.

Signed-off-by: Ilie Halip <ilie.halip@gmail.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2020-01-18 13:22:13 -08:00
Greentime Hu
20d2292754 riscv: make sure the cores stay looping in .Lsecondary_park
The code in secondary_park is currently placed in the .init section. The
kernel reclaims and clears this code when it finishes booting. That
causes the cores parked in it to go to somewhere unpredictable, so we
move this function out of init to make sure the cores stay looping there.

The instruction bgeu a0, t0, .Lsecondary_park may have "a relocation
truncated to fit" issue during linking time. It is because that sections
are too far to jump. Let's use tail to jump to the .Lsecondary_park.

Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Anup Patel <anup.patel@sifive.com>
Cc: Andreas Schwab <schwab@suse.de>
Cc: stable@vger.kernel.org
Fixes: 76d2a0493a ("RISC-V: Init and Halt Code")
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2020-01-15 18:07:54 -08:00
Arvind Sankar
2680e04c18 arch/riscv/setup: Drop dummy_con initialization
con_init in tty/vt.c will now set conswitchp to dummy_con if it's unset.
Drop it from arch setup code.

Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
Link: https://lore.kernel.org/r/20191218214506.49252-19-nivedita@alum.mit.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-14 15:29:18 +01:00
Linus Torvalds
373adb7313 Merge tag 'riscv/for-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Paul Walmsley:
 "Two fixes for RISC-V:

   - Clear FP registers during boot when FP support is present, rather
     than when they aren't present

   - Move the header files associated with the SiFive L2 cache
     controller to drivers/soc (where the code was recently moved)"

* tag 'riscv/for-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Fixup obvious bug for fp-regs reset
  riscv: move sifive_l2_cache.h to include/soc
2020-01-12 16:48:39 -08:00
Guo Ren
dc6fcba72f riscv: Fixup obvious bug for fp-regs reset
CSR_MISA is defined in Privileged Architectures' spec: 3.1.1 Machine
ISA Register misa. Every bit:1 indicate a feature, so we should beqz
reset_done when there is no F/D bit in csr_misa register.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
[paul.walmsley@sifive.com: fix typo in commit message]
Fixes: 9e80635619 ("riscv: clear the instruction cache and all registers when booting")
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2020-01-12 10:12:44 -08:00
Amanieu d'Antras
20bda4ed62 riscv: Implement copy_thread_tls
This is required for clone3 which passes the TLS value through a
struct rather than a register.

Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: linux-riscv@lists.infradead.org
Cc: <stable@vger.kernel.org> # 5.3.x
Link: https://lore.kernel.org/r/20200102172413.654385-6-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-01-07 13:31:23 +01:00
Paul Walmsley
2f3035da40 riscv: prefix IRQ_ macro names with an RV_ namespace
"IRQ_TIMER", used in the arch/riscv CSR header file, is a sufficiently
generic macro name that it's used by several source files across the
Linux code base.  Some of these other files ultimately include the
arch/riscv CSR include file, causing collisions.  Fix by prefixing the
RISC-V csr.h IRQ_ macro names with an RV_ prefix.

Fixes: a4c3733d32 ("riscv: abstract out CSR names for supervisor vs machine mode")
Reported-by: Olof Johansson <olof@lixom.net>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2020-01-04 21:48:59 -08:00
Zong Li
1d8f657982 riscv: ftrace: correct the condition logic in function graph tracer
The condition should be logical NOT to assign the hook address to parent
address. Because the return value 0 of function_graph_enter upon
success.

Fixes: e949b6db51 (riscv/function_graph: Simplify with function_graph_enter())
Signed-off-by: Zong Li <zong.li@sifive.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: stable@vger.kernel.org
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2020-01-03 00:56:37 -08:00
David Abdurachmanov
556f47ac60 riscv: reject invalid syscalls below -1
Running "stress-ng --enosys 4 -t 20 -v" showed a large number of kernel oops
with "Unable to handle kernel paging request at virtual address" message. This
happens when enosys stressor starts testing random non-valid syscalls.

I forgot to redirect any syscall below -1 to sys_ni_syscall.

With the patch kernel oops messages are gone while running stress-ng enosys
stressor.

Signed-off-by: David Abdurachmanov <david.abdurachmanov@sifive.com>
Fixes: 5340627e3f ("riscv: add support for SECCOMP and SECCOMP_FILTER")
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-12-27 21:50:57 -08:00
Luc Van Oostenryck
4d47ce158e riscv: fix compile failure with EXPORT_SYMBOL() & !MMU
When support for !MMU was added, the declaration of
__asm_copy_to_user() & __asm_copy_from_user() were #ifdefed
out hence their EXPORT_SYMBOL() give an error message like:
  .../riscv_ksyms.c:13:15: error: '__asm_copy_to_user' undeclared here
  .../riscv_ksyms.c:14:15: error: '__asm_copy_from_user' undeclared here

Since these symbols are not defined with !MMU it's wrong to export them.
Same for __clear_user() (even though this one is also declared in
include/asm-generic/uaccess.h and thus doesn't give an error message).

Fix this by doing the EXPORT_SYMBOL() directly where these symbols
are defined: inside lib/uaccess.S itself.

Fixes: 6bd33e1ece ("riscv: fix compile failure with EXPORT_SYMBOL() & !MMU")
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-12-27 21:44:36 -08:00
Ingo Molnar
1e5f8a3085 Merge tag 'v5.5-rc3' into sched/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-25 10:41:37 +01:00
Greentime Hu
d411cf02ed riscv: fix scratch register clearing in M-mode.
This patch fixes that the sscratch register clearing in M-mode. It cleared
sscratch register in M-mode, but it should clear mscratch register. That will
cause kernel trap if the CPU core doesn't support S-mode when trying to access
sscratch.

Fixes: 9e80635619 ("riscv: clear the instruction cache and all registers when booting")
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-12-20 03:32:24 -08:00
Thomas Gleixner
29ff64929e sched/rt, riscv: Use CONFIG_PREEMPTION
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.

Switch the entry code over to use CONFIG_PREEMPTION.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul Walmsley <paul.walmsley@sifive.com> # for arch/riscv
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-riscv@lists.infradead.org
Link: https://lore.kernel.org/r/20191015191821.11479-17-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-12-08 14:37:34 +01:00
Linus Torvalds
b94ae8ad9f Merge tag 'seccomp-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp updates from Kees Cook:
 "Mostly this is implementing the new flag SECCOMP_USER_NOTIF_FLAG_CONTINUE,
  but there are cleanups as well.

   - implement SECCOMP_USER_NOTIF_FLAG_CONTINUE (Christian Brauner)

   - fixes to selftests (Christian Brauner)

   - remove secure_computing() argument (Christian Brauner)"

* tag 'seccomp-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  seccomp: rework define for SECCOMP_USER_NOTIF_FLAG_CONTINUE
  seccomp: fix SECCOMP_USER_NOTIF_FLAG_CONTINUE test
  seccomp: simplify secure_computing()
  seccomp: test SECCOMP_USER_NOTIF_FLAG_CONTINUE
  seccomp: add SECCOMP_USER_NOTIF_FLAG_CONTINUE
  seccomp: avoid overflow in implicit constant conversion
2019-11-30 17:23:16 -08:00
Linus Torvalds
6a0e20cd8c Merge tag 'riscv/for-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Paul Walmsley:
 "New features:
   - SECCOMP support
   - nommu support
   - SBI-less system support
   - M-Mode support
   - TLB flush optimizations

  Other improvements:
   - Pass the complete RISC-V ISA string supported by the CPU cores to
     userspace, rather than redacting parts of it in the kernel
   - Add platform DMA IP block data to the HiFive Unleashed board DT
     file
   - Add Makefile support for BZ2, LZ4, LZMA, LZO kernel image
     compression formats, in line with other architectures

  Cleanups:
   - Remove unnecessary PTE_PARENT_SIZE macro
   - Standardize include guard naming across arch/riscv"

* tag 'riscv/for-v5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (22 commits)
  riscv: provide a flat image loader
  riscv: add nommu support
  riscv: clear the instruction cache and all registers when booting
  riscv: read the hart ID from mhartid on boot
  riscv: provide native clint access for M-mode
  riscv: dts: add support for PDMA device of HiFive Unleashed Rev A00
  riscv: add support for MMIO access to the timer registers
  riscv: implement remote sfence.i using IPIs
  riscv: cleanup the default power off implementation
  riscv: poison SBI calls for M-mode
  riscv: don't allow selecting SBI based drivers for M-mode
  RISC-V: Add multiple compression image format.
  riscv: clean up the macro format in each header file
  riscv: Use PMD_SIZE to replace PTE_PARENT_SIZE
  riscv: abstract out CSR names for supervisor vs machine mode
  riscv: separate MMIO functions into their own header file
  riscv: enter WFI in default_power_off() if SBI does not shutdown
  RISC-V: Issue a tlb page flush if possible
  RISC-V: Issue a local tlbflush if possible.
  RISC-V: Do not invoke SBI call if cpumask is empty
  ...
2019-11-27 11:27:59 -08:00
Linus Torvalds
1d87200446 Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 asm updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Cross-arch changes to move the linker sections for NOTES and
     EXCEPTION_TABLE into the RO_DATA area, where they belong on most
     architectures. (Kees Cook)

   - Switch the x86 linker fill byte from x90 (NOP) to 0xcc (INT3), to
     trap jumps into the middle of those padding areas instead of
     sliding execution. (Kees Cook)

   - A thorough cleanup of symbol definitions within x86 assembler code.
     The rather randomly named macros got streamlined around a
     (hopefully) straightforward naming scheme:

        SYM_START(name, linkage, align...)
        SYM_END(name, sym_type)

        SYM_FUNC_START(name)
        SYM_FUNC_END(name)

        SYM_CODE_START(name)
        SYM_CODE_END(name)

        SYM_DATA_START(name)
        SYM_DATA_END(name)

     etc - with about three times of these basic primitives with some
     label, local symbol or attribute variant, expressed via postfixes.

     No change in functionality intended. (Jiri Slaby)

   - Misc other changes, cleanups and smaller fixes"

* 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
  x86/entry/64: Remove pointless jump in paranoid_exit
  x86/entry/32: Remove unused resume_userspace label
  x86/build/vdso: Remove meaningless CFLAGS_REMOVE_*.o
  m68k: Convert missed RODATA to RO_DATA
  x86/vmlinux: Use INT3 instead of NOP for linker fill bytes
  x86/mm: Report actual image regions in /proc/iomem
  x86/mm: Report which part of kernel image is freed
  x86/mm: Remove redundant address-of operators on addresses
  xtensa: Move EXCEPTION_TABLE to RO_DATA segment
  powerpc: Move EXCEPTION_TABLE to RO_DATA segment
  parisc: Move EXCEPTION_TABLE to RO_DATA segment
  microblaze: Move EXCEPTION_TABLE to RO_DATA segment
  ia64: Move EXCEPTION_TABLE to RO_DATA segment
  h8300: Move EXCEPTION_TABLE to RO_DATA segment
  c6x: Move EXCEPTION_TABLE to RO_DATA segment
  arm64: Move EXCEPTION_TABLE to RO_DATA segment
  alpha: Move EXCEPTION_TABLE to RO_DATA segment
  x86/vmlinux: Move EXCEPTION_TABLE to RO_DATA segment
  x86/vmlinux: Actually use _etext for the end of the text segment
  vmlinux.lds.h: Allow EXCEPTION_TABLE to live in RO_DATA
  ...
2019-11-26 10:42:40 -08:00
Linus Torvalds
436b2a8039 Merge tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:

 - Allow to print symbolic error names via new %pe modifier.

 - Use pr_warn() instead of the remaining pr_warning() calls. Fix
   formatting of the related lines.

 - Add VSPRINTF entry to MAINTAINERS.

* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
  checkpatch: don't warn about new vsprintf pointer extension '%pe'
  MAINTAINERS: Add VSPRINTF
  tools lib api: Renaming pr_warning to pr_warn
  ASoC: samsung: Use pr_warn instead of pr_warning
  lib: cpu_rmap: Use pr_warn instead of pr_warning
  trace: Use pr_warn instead of pr_warning
  dma-debug: Use pr_warn instead of pr_warning
  vgacon: Use pr_warn instead of pr_warning
  fs: afs: Use pr_warn instead of pr_warning
  sh/intc: Use pr_warn instead of pr_warning
  scsi: Use pr_warn instead of pr_warning
  platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
  platform/x86: asus-laptop: Use pr_warn instead of pr_warning
  platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
  oprofile: Use pr_warn instead of pr_warning
  of: Use pr_warn instead of pr_warning
  macintosh: Use pr_warn instead of pr_warning
  idsn: Use pr_warn instead of pr_warning
  ide: Use pr_warn instead of pr_warning
  crypto: n2: Use pr_warn instead of pr_warning
  ...
2019-11-25 19:40:40 -08:00
Paul Walmsley
5ba9aa56e6 Merge branch 'next/nommu' into for-next
Conflicts:
	arch/riscv/boot/Makefile
	arch/riscv/include/asm/sbi.h
2019-11-22 18:59:09 -08:00
Paul Walmsley
9acfd6f538 Merge branch 'next/isa-string' into for-next 2019-11-22 18:58:29 -08:00
Christoph Hellwig
6bd33e1ece riscv: add nommu support
The kernel runs in M-mode without using page tables, and thus can't run
bare metal without help from additional firmware.

Most of the patch is just stubbing out code not needed without page
tables, but there is an interesting detail in the signals implementation:

 - The normal RISC-V syscall ABI only implements rt_sigreturn as VDSO
   entry point, but the ELF VDSO is not supported for nommu Linux.
   We instead copy the code to call the syscall onto the stack.

In addition to enabling the nommu code a new defconfig for a small
kernel image that can run in nommu mode on qemu is also provided, to run
a kernel in qemu you can use the following command line:

qemu-system-riscv64 -smp 2 -m 64 -machine virt -nographic \
	-kernel arch/riscv/boot/loader \
	-drive file=rootfs.ext2,format=raw,id=hd0 \
	-device virtio-blk-device,drive=hd0

Contains contributions from Damien Le Moal <Damien.LeMoal@wdc.com>.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: updated to apply; add CONFIG_MMU guards
 around PCI_IOBASE definition to fix build issues; fixed checkpatch
 issues; move the PCI_IO_* and VMEMMAP address space macros along
 with the others; resolve sparse warning]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-17 15:17:39 -08:00
Christoph Hellwig
9e80635619 riscv: clear the instruction cache and all registers when booting
When we get booted we want a clear slate without any leaks from previous
supervisors or the firmware.  Flush the instruction cache and then clear
all registers to known good values.  This is really important for the
upcoming nommu support that runs on M-mode, but can't really harm when
running in S-mode either.  Vaguely based on the concepts from opensbi.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-17 15:17:39 -08:00
Damien Le Moal
accb9dbc4a riscv: read the hart ID from mhartid on boot
When in M-Mode, we can use the mhartid CSR to get the ID of the running
HART. Doing so, direct M-Mode boot without firmware is possible.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-17 15:17:39 -08:00
Christoph Hellwig
fcdc653751 riscv: provide native clint access for M-mode
RISC-V has the concept of a cpu level interrupt controller.  The
interface for it is split between a standardized part that is exposed
as bits in the mstatus/sstatus register and the mie/mip/sie/sip
CRS.  But the bit to actually trigger IPIs is not standardized and
just mentioned as implementable using MMIO.

Add support for IPIs using MMIO using the SiFive clint layout (which
is also shared by Ariane, Kendryte and the Qemu virt platform).
Additionally the MMIO block also supports the time value and timer
compare registers, so they are also set up using the same OF node.
Support for other layouts should also be relatively easy to add in the
future.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
[paul.walmsley@sifive.com: update include guard format; fix checkpatch
 issues; minor commit message cleanup]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-17 15:17:39 -08:00
Christoph Hellwig
3320648ecc riscv: cleanup the default power off implementation
Move the sbi poweroff to a separate function and file that is only
compiled if CONFIG_SBI is set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
[paul.walmsley@sifive.com: split the WFI fix into a separate patch]
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
2019-11-13 13:22:52 -08:00