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Author SHA1 Message Date
Linus Torvalds
d46392bbf5 RISC-V Patches for the 6.7 Merge Window, Part 1
* Support for cbo.zero in userspace.
 * Support for CBOs on ACPI-based systems.
 * A handful of improvements for the T-Head cache flushing ops.
 * Support for software shadow call stacks.
 * Various cleanups and fixes.
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Merge tag 'riscv-for-linus-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Support for cbo.zero in userspace

 - Support for CBOs on ACPI-based systems

 - A handful of improvements for the T-Head cache flushing ops

 - Support for software shadow call stacks

 - Various cleanups and fixes

* tag 'riscv-for-linus-6.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (31 commits)
  RISC-V: hwprobe: Fix vDSO SIGSEGV
  riscv: configs: defconfig: Enable configs required for RZ/Five SoC
  riscv: errata: prefix T-Head mnemonics with th.
  riscv: put interrupt entries into .irqentry.text
  riscv: mm: Update the comment of CONFIG_PAGE_OFFSET
  riscv: Using TOOLCHAIN_HAS_ZIHINTPAUSE marco replace zihintpause
  riscv/mm: Fix the comment for swap pte format
  RISC-V: clarify the QEMU workaround in ISA parser
  riscv: correct pt_level name via pgtable_l5/4_enabled
  RISC-V: Provide pgtable_l5_enabled on rv32
  clocksource: timer-riscv: Increase rating of clock_event_device for Sstc
  clocksource: timer-riscv: Don't enable/disable timer interrupt
  lkdtm: Fix CFI_BACKWARD on RISC-V
  riscv: Use separate IRQ shadow call stacks
  riscv: Implement Shadow Call Stack
  riscv: Move global pointer loading to a macro
  riscv: Deduplicate IRQ stack switching
  riscv: VMAP_STACK overflow detection thread-safe
  RISC-V: cacheflush: Initialize CBO variables on ACPI systems
  RISC-V: ACPI: RHCT: Add function to get CBO block sizes
  ...
2023-11-08 09:21:18 -08:00
Arnd Bergmann
b8466fe82b efi: move screen_info into efi init code
After the vga console no longer relies on global screen_info, there are
only two remaining use cases:

 - on the x86 architecture, it is used for multiple boot methods
   (bzImage, EFI, Xen, kexec) to commucate the initial VGA or framebuffer
   settings to a number of device drivers.

 - on other architectures, it is only used as part of the EFI stub,
   and only for the three sysfb framebuffers (simpledrm, simplefb, efifb).

Remove the duplicate data structure definitions by moving it into the
efi-init.c file that sets it up initially for the EFI case, leaving x86
as an exception that retains its own definition for non-EFI boots.

The added #ifdefs here are optional, I added them to further limit the
reach of screen_info to configurations that have at least one of the
users enabled.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20231017093947.3627976-1-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-17 16:33:39 +02:00
Arnd Bergmann
8a736ddfc8 vgacon: rework screen_info #ifdef checks
On non-x86 architectures, the screen_info variable is generally only
used for the VGA console where supported, and in some cases the EFI
framebuffer or vga16fb.

Now that we have a definite list of which architectures actually use it
for what, use consistent #ifdef checks so the global variable is only
defined when it is actually used on those architectures.

Loongarch and riscv have no support for vgacon or vga16fb, but
they support EFI firmware, so only that needs to be checked, and the
initialization can be removed because that is handled by EFI.
IA64 has both vgacon and EFI, though EFI apparently never uses
a framebuffer here.

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Khalid Aziz <khalid@gonehiking.org>
Acked-by: Helge Deller <deller@gmx.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20231009211845.3136536-3-arnd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-17 10:17:02 +02:00
Chen Jiahao
1d6cd2146c
riscv: kdump: fix crashkernel reserving problem on RISC-V
When testing on risc-v QEMU environment with "crashkernel="
parameter enabled, a problem occurred with the following
message:

[    0.000000] crashkernel low memory reserved: 0xf8000000 - 0x100000000 (128 MB)
[    0.000000] crashkernel reserved: 0x0000000177e00000 - 0x0000000277e00000 (4096 MB)
[    0.000000] ------------[ cut here ]------------
[    0.000000] WARNING: CPU: 0 PID: 0 at kernel/resource.c:779 __insert_resource+0x8e/0xd0
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.6.0-rc2-next-20230920 #1
[    0.000000] Hardware name: riscv-virtio,qemu (DT)
[    0.000000] epc : __insert_resource+0x8e/0xd0
[    0.000000]  ra : insert_resource+0x28/0x4e
[    0.000000] epc : ffffffff80017344 ra : ffffffff8001742e sp : ffffffff81203db0
[    0.000000]  gp : ffffffff812ece98 tp : ffffffff8120dac0 t0 : ff600001f7ff2b00
[    0.000000]  t1 : 0000000000000000 t2 : 3428203030303030 s0 : ffffffff81203dc0
[    0.000000]  s1 : ffffffff81211e18 a0 : ffffffff81211e18 a1 : ffffffff81289380
[    0.000000]  a2 : 0000000277dfffff a3 : 0000000177e00000 a4 : 0000000177e00000
[    0.000000]  a5 : ffffffff81289380 a6 : 0000000277dfffff a7 : 0000000000000078
[    0.000000]  s2 : ffffffff81289380 s3 : ffffffff80a0bac8 s4 : ff600001f7ff2880
[    0.000000]  s5 : 0000000000000280 s6 : 8000000a00006800 s7 : 000000000000007f
[    0.000000]  s8 : 0000000080017038 s9 : 0000000080038ea0 s10: 0000000000000000
[    0.000000]  s11: 0000000000000000 t3 : ffffffff80a0bc00 t4 : ffffffff80a0bc00
[    0.000000]  t5 : ffffffff80a0bbd0 t6 : ffffffff80a0bc00
[    0.000000] status: 0000000200000100 badaddr: 0000000000000000 cause: 0000000000000003
[    0.000000] [<ffffffff80017344>] __insert_resource+0x8e/0xd0
[    0.000000] ---[ end trace 0000000000000000 ]---
[    0.000000] Failed to add a Crash kernel resource at 177e00000

The crashkernel memory has been allocated successfully, whereas
it failed to insert into iomem_resource. This is due to the
unique reserving logic in risc-v arch specific code, i.e.
crashk_res/crashk_low_res will be added into iomem_resource
later in init_resources(), which is not aligned with current
unified reserving logic in reserve_crashkernel_{generic,low}()
and therefore leads to the failure of crashkernel reservation.

Removing the arch specific code within #ifdef CONFIG_KEXEC_CORE
in init_resources() to fix above problem.

Fixes: 31549153088e ("riscv: kdump: use generic interface to simplify crashkernel reservation")
Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com>
Link: https://lore.kernel.org/r/20230925024333.730964-1-chenjiahao16@huawei.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-10-12 11:34:09 -07:00
Andrew Jones
43c16d51a1
RISC-V: Enable cbo.zero in usermode
When Zicboz is present, enable its instruction (cbo.zero) in
usermode by setting its respective senvcfg bit. We don't bother
trying to set this bit per-task, which would also require an
interface for tasks to request enabling and/or disabling. Instead,
permanently set the bit for each hart which has the extension when
bringing it online.

This patch also introduces riscv_cpu_has_extension_[un]likely()
functions to check a specific hart's ISA bitmap for extensions.
Prior to checking the specific hart's bitmap in these functions
we try the bitmap which represents the LCD of extensions, but only
when we know it will use its optimized, alternatives path by gating
its call on CONFIG_RISCV_ALTERNATIVE. When alternatives are used, the
compiler ensures that the invocation of the LCD search becomes a
constant true or false. When it's true, even the new functions will
completely vanish from their callsites. OTOH, when the LCD check is
false, we need to do a search of the hart's ISA bitmap. Had we also
checked the LCD bitmap without the use of alternatives, then we would
have ended up with two bitmap searches instead of one.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230918131518.56803-10-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-21 04:22:24 -07:00
Palmer Dabbelt
f578055558
Merge patch series "riscv: Introduce KASLR"
Alexandre Ghiti <alexghiti@rivosinc.com> says:

The following KASLR implementation allows to randomize the kernel mapping:

- virtually: we expect the bootloader to provide a seed in the device-tree
- physically: only implemented in the EFI stub, it relies on the firmware to
  provide a seed using EFI_RNG_PROTOCOL. arm64 has a similar implementation
  hence the patch 3 factorizes KASLR related functions for riscv to take
  advantage.

The new virtual kernel location is limited by the early page table that only
has one PUD and with the PMD alignment constraint, the kernel can only take
< 512 positions.

* b4-shazam-merge:
  riscv: libstub: Implement KASLR by using generic functions
  libstub: Fix compilation warning for rv32
  arm64: libstub: Move KASLR handling functions to kaslr.c
  riscv: Dump out kernel offset information on panic
  riscv: Introduce virtual kernel mapping KASLR

Link: https://lore.kernel.org/r/20230722123850.634544-1-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-08 11:25:13 -07:00
Alexandre Ghiti
54a519e6af
riscv: Dump out kernel offset information on panic
Dump out the KASLR virtual kernel offset when panic to help debug kernel.

Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Song Shuai <songshuaishuai@tinylab.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Tested-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/r/20230722123850.634544-3-alexghiti@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-09-05 19:49:28 -07:00
Palmer Dabbelt
52b77c2806
Merge patch series "riscv: Reduce ARCH_KMALLOC_MINALIGN to 8"
Jisheng Zhang <jszhang@kernel.org> says:

Currently, riscv defines ARCH_DMA_MINALIGN as L1_CACHE_BYTES, I.E
64Bytes, if CONFIG_RISCV_DMA_NONCOHERENT=y. To support unified kernel
Image, usually we have to enable CONFIG_RISCV_DMA_NONCOHERENT, thus
it brings some bad effects to coherent platforms:

Firstly, it wastes memory, kmalloc-96, kmalloc-32, kmalloc-16 and
kmalloc-8 slab caches don't exist any more, they are replaced with
either kmalloc-128 or kmalloc-64.

Secondly, larger than necessary kmalloc aligned allocations results
in unnecessary cache/TLB pressure.

This issue also exists on arm64 platforms. From last year, Catalin
tried to solve this issue by decoupling ARCH_KMALLOC_MINALIGN from
ARCH_DMA_MINALIGN, limiting kmalloc() minimum alignment to
dma_get_cache_alignment() and replacing ARCH_KMALLOC_MINALIGN usage
in various drivers with ARCH_DMA_MINALIGN etc.[1]

One fact we can make use of for riscv: if the CPU doesn't support
ZICBOM or T-HEAD CMO, we know the platform is coherent. Based on
Catalin's work and above fact, we can easily solve the kmalloc align
issue for riscv: we can override dma_get_cache_alignment(), then let
it return ARCH_DMA_MINALIGN at the beginning and return 1 once we know
the underlying HW neither supports ZICBOM nor supports T-HEAD CMO.

So what about if the CPU supports ZICBOM or T-HEAD CMO, but all the
devices are dma coherent? Well, we use ARCH_DMA_MINALIGN as the
kmalloc minimum alignment, nothing changed in this case. This case
can be improved in the future once we see such platforms in mainline.

After this patch, a simple test of booting to a small buildroot rootfs
on qemu shows:

kmalloc-96           5041    5041     96  ...
kmalloc-64           9606    9606     64  ...
kmalloc-32           5128    5128     32  ...
kmalloc-16           7682    7682     16  ...
kmalloc-8           10246   10246      8  ...

So we save about 1268KB memory. The saving will be much larger in normal
OS env on real HW platforms.

patch1 allows kmalloc() caches aligned to the smallest value.
patch2 enables DMA_BOUNCE_UNALIGNED_KMALLOC.

After this series:

As for coherent platforms, kmalloc-{8,16,32,96} caches come back on
coherent both RV32 and RV64 platforms, I.E !ZICBOM and !THEAD_CMO.

As for noncoherent RV32 platforms, nothing changed.

As for noncoherent RV64 platforms, I.E either ZICBOM or THEAD_CMO, the
above kmalloc caches also come back if > 4GB memory or users pass
"swiotlb=mmnn,force" to force swiotlb creation if <= 4GB memory. How
much mmnn should be depends on the specific platform, it needs to be
tried and tested all possible usage case on the specific hardware. For
example, I can use the minimal I/O TLB slabs on Sipeed M1S Dock.

* b4-shazam-merge:
  riscv: enable DMA_BOUNCE_UNALIGNED_KMALLOC for !dma_coherent
  riscv: allow kmalloc() caches aligned to the smallest value

Link: https://lore.kernel.org/linux-arm-kernel/20230524171904.3967031-1-catalin.marinas@arm.com/ [1]
Link: https://lore.kernel.org/r/20230718152214.2907-1-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-31 00:18:35 -07:00
Jisheng Zhang
2926715163
riscv: allow kmalloc() caches aligned to the smallest value
Currently, riscv defines ARCH_DMA_MINALIGN as L1_CACHE_BYTES, I.E
64Bytes, if CONFIG_RISCV_DMA_NONCOHERENT=y. To support unified kernel
Image, usually we have to enable CONFIG_RISCV_DMA_NONCOHERENT, thus
it brings some bad effects to coherent platforms:

Firstly, it wastes memory, kmalloc-96, kmalloc-32, kmalloc-16 and
kmalloc-8 slab caches don't exist any more, they are replaced with
either kmalloc-128 or kmalloc-64.

Secondly, larger than necessary kmalloc aligned allocations results
in unnecessary cache/TLB pressure.

This issue also exists on arm64 platforms. From last year, Catalin
tried to solve this issue by decoupling ARCH_KMALLOC_MINALIGN from
ARCH_DMA_MINALIGN, limiting kmalloc() minimum alignment to
dma_get_cache_alignment() and replacing ARCH_KMALLOC_MINALIGN usage
in various drivers with ARCH_DMA_MINALIGN etc.[1]

One fact we can make use of for riscv: if the CPU doesn't support
ZICBOM or T-HEAD CMO, we know the platform is coherent. Based on
Catalin's work and above fact, we can easily solve the kmalloc align
issue for riscv: we can override dma_get_cache_alignment(), then let
it return ARCH_DMA_MINALIGN at the beginning and return 1 once we know
the underlying HW neither supports ZICBOM nor supports T-HEAD CMO.

So what about if the CPU supports ZICBOM or T-HEAD CMO, but all the
devices are dma coherent? Well, we use ARCH_DMA_MINALIGN as the
kmalloc minimum alignment, nothing changed in this case. This case
can be improved in the future.

After this patch, a simple test of booting to a small buildroot rootfs
on qemu shows:

kmalloc-96           5041    5041     96  ...
kmalloc-64           9606    9606     64  ...
kmalloc-32           5128    5128     32  ...
kmalloc-16           7682    7682     16  ...
kmalloc-8           10246   10246      8  ...

So we save about 1268KB memory. The saving will be much larger in normal
OS env on real HW platforms.

Link: https://lore.kernel.org/linux-arm-kernel/20230524171904.3967031-1-catalin.marinas@arm.com/ [1]

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230718152214.2907-2-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-23 14:22:00 -07:00
Chen Jiahao
5882e5acf1
riscv: kdump: Implement crashkernel=X,[high,low]
On riscv, the current crash kernel allocation logic is trying to
allocate within 32bit addressible memory region by default, if
failed, try to allocate without 4G restriction.

In need of saving DMA zone memory while allocating a relatively large
crash kernel region, allocating the reserved memory top down in
high memory, without overlapping the DMA zone, is a mature solution.
Here introduce the parameter option crashkernel=X,[high,low].

One can reserve the crash kernel from high memory above DMA zone range
by explicitly passing "crashkernel=X,high"; or reserve a memory range
below 4G with "crashkernel=X,low".

Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com>
Acked-by: Guo Ren <guoren@kernel.org>
Acked-by: Baoquan He <bhe@redhat.com>
Link: https://lore.kernel.org/r/20230726175000.2536220-2-chenjiahao16@huawei.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-08-16 07:51:48 -07:00
Palmer Dabbelt
d5e45e810e
Merge patch series "riscv: Add vector ISA support"
Andy Chiu <andy.chiu@sifive.com> says:

This is the v21 patch series for adding Vector extension support in
Linux. Please refer to [1] for the introduction of the patchset. The
v21 patch series was aimed to solve build issues from v19, provide usage
guideline for the prctl interface, and address review comments on v20.

Thank every one who has been reviewing, suggesting on the topic. Hope
this get a step closer to the final merge.

* b4-shazam-merge: (27 commits)
  selftests: add .gitignore file for RISC-V hwprobe
  selftests: Test RISC-V Vector prctl interface
  riscv: Add documentation for Vector
  riscv: Enable Vector code to be built
  riscv: detect assembler support for .option arch
  riscv: Add sysctl to set the default vector rule for new processes
  riscv: Add prctl controls for userspace vector management
  riscv: hwcap: change ELF_HWCAP to a function
  riscv: KVM: Add vector lazy save/restore support
  riscv: kvm: Add V extension to KVM ISA
  riscv: prevent stack corruption by reserving task_pt_regs(p) early
  riscv: signal: validate altstack to reflect Vector
  riscv: signal: Report signal frame size to userspace via auxv
  riscv: signal: Add sigcontext save/restore for vector
  riscv: signal: check fp-reserved words unconditionally
  riscv: Add ptrace vector support
  riscv: Allocate user's vector context in the first-use trap
  riscv: Add task switch support for vector
  riscv: Introduce struct/helpers to save/restore per-task Vector state
  riscv: Introduce riscv_v_vsize to record size of Vector context
  ...

Link: https://lore.kernel.org/r/20230605110724.21391-1-andy.chiu@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08 07:17:09 -07:00
Greentime Hu
8ee0b41898
riscv: signal: Add sigcontext save/restore for vector
This patch facilitates the existing fp-reserved words for placement of
the first extension's context header on the user's sigframe. A context
header consists of a distinct magic word and the size, including the
header itself, of an extension on the stack. Then, the frame is followed
by the context of that extension, and then a header + context body for
another extension if exists. If there is no more extension to come, then
the frame must be ended with a null context header. A special case is
rv64gc, where the kernel support no extensions requiring to expose
additional regfile to the user. In such case the kernel would place the
null context header right after the first reserved word of
__riscv_q_ext_state when saving sigframe. And the kernel would check if
all reserved words are zeros when a signal handler returns.

__riscv_q_ext_state---->|	|<-__riscv_extra_ext_header
			~	~
	.reserved[0]--->|0	|<-	.reserved
		<-------|magic	|<-	.hdr
		|	|size	|_______ end of sc_fpregs
		|	|ext-bdy|
		|	~	~
	+)size	------->|magic	|<- another context header
			|size	|
			|ext-bdy|
			~	~
			|magic:0|<- null context header
			|size:0	|

The vector registers will be saved in datap pointer. The datap pointer
will be allocated dynamically when the task needs in kernel space. On
the other hand, datap pointer on the sigframe will be set right after
the __riscv_v_ext_state data structure.

Co-developed-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Suggested-by: Vineet Gupta <vineetg@rivosinc.com>
Suggested-by: Richard Henderson <richard.henderson@linaro.org>
Co-developed-by: Andy Chiu <andy.chiu@sifive.com>
Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Acked-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Link: https://lore.kernel.org/r/20230605110724.21391-15-andy.chiu@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-08 07:16:47 -07:00
Sunil V L
f995611994
RISC-V: ACPI: Cache and retrieve the RINTC structure
RINTC structures in the MADT provide mapping between the hartid
and the CPU. This is required many times even at run time like
cpuinfo. So, instead of parsing the ACPI table every time, cache
the RINTC structures and provide a function to get the correct
RINTC structure for a given cpu.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20230515054928.2079268-10-sunilvl@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01 08:45:03 -07:00
Sunil V L
724f4c0df7
RISC-V: Add ACPI initialization in setup_arch()
Initialize the ACPI core for RISC-V during boot.

ACPI tables and interpreter are initialized based on
the information passed from the firmware and the value of
the kernel parameter 'acpi'.

With ACPI support added for RISC-V, the kernel parameter 'acpi'
is also supported on RISC-V. Hence, update the documentation.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230515054928.2079268-9-sunilvl@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01 08:45:03 -07:00
Jisheng Zhang
24fc18087f
riscv: move sbi_init() earlier before jump_label_init()
We call jump_label_init() in setup_arch() is to use static key
mechanism earlier, but riscv jump label relies on the sbi functions,
If we enable static key before sbi_init(), the code path looks like:
  static_branch_enable()
    ..
      arch_jump_label_transform()
        patch_text_nosync()
          flush_icache_range()
            flush_icache_all()
              sbi_remote_fence_i() for CONFIG_RISCV_SBI case
                __sbi_rfence()

Since sbi isn't initialized, so NULL deference! Here is a typical
panic log:

[    0.000000] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
[    0.000000] Oops [#1]
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0-rc7+ #79
[    0.000000] Hardware name: riscv-virtio,qemu (DT)
[    0.000000] epc : 0x0
[    0.000000]  ra : sbi_remote_fence_i+0x1e/0x26
[    0.000000] epc : 0000000000000000 ra : ffffffff80005826 sp : ffffffff80c03d50
[    0.000000]  gp : ffffffff80ca6178 tp : ffffffff80c0ad80 t0 : 6200000000000000
[    0.000000]  t1 : 0000000000000000 t2 : 62203a6b746e6972 s0 : ffffffff80c03d60
[    0.000000]  s1 : ffffffff80001af6 a0 : 0000000000000000 a1 : 0000000000000000
[    0.000000]  a2 : 0000000000000000 a3 : 0000000000000000 a4 : 0000000000000000
[    0.000000]  a5 : 0000000000000000 a6 : 0000000000000000 a7 : 0000000000080200
[    0.000000]  s2 : ffffffff808b3e48 s3 : ffffffff808bf698 s4 : ffffffff80cb2818
[    0.000000]  s5 : 0000000000000001 s6 : ffffffff80c9c345 s7 : ffffffff80895aa0
[    0.000000]  s8 : 0000000000000001 s9 : 000000000000007f s10: 0000000000000000
[    0.000000]  s11: 0000000000000000 t3 : ffffffff80824d08 t4 : 0000000000000022
[    0.000000]  t5 : 000000000000003d t6 : 0000000000000000
[    0.000000] status: 0000000000000100 badaddr: 0000000000000000 cause: 000000000000000c
[    0.000000] ---[ end trace 0000000000000000 ]---
[    0.000000] Kernel panic - not syncing: Attempted to kill the idle task!
[    0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]---

Fix this issue by moving sbi_init() earlier before jump_label_init()

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20230515054928.2079268-2-sunilvl@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-06-01 08:44:56 -07:00
Linus Torvalds
89d77f71f4 RISC-V Patches for the 6.4 Merge Window, Part 1
* Support for runtime detection of the Svnapot extension.
 * Support for Zicboz when clearing pages.
 * We've moved to GENERIC_ENTRY.
 * Support for !MMU on rv32 systems.
 * The linear region is now mapped via huge pages.
 * Support for building relocatable kernels.
 * Support for the hwprobe interface.
 * Various fixes and cleanups throughout the tree.
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Merge tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Support for runtime detection of the Svnapot extension

 - Support for Zicboz when clearing pages

 - We've moved to GENERIC_ENTRY

 - Support for !MMU on rv32 systems

 - The linear region is now mapped via huge pages

 - Support for building relocatable kernels

 - Support for the hwprobe interface

 - Various fixes and cleanups throughout the tree

* tag 'riscv-for-linus-6.4-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (57 commits)
  RISC-V: hwprobe: Explicity check for -1 in vdso init
  RISC-V: hwprobe: There can only be one first
  riscv: Allow to downgrade paging mode from the command line
  dt-bindings: riscv: add sv57 mmu-type
  RISC-V: hwprobe: Remove __init on probe_vendor_features()
  riscv: Use --emit-relocs in order to move .rela.dyn in init
  riscv: Check relocations at compile time
  powerpc: Move script to check relocations at compile time in scripts/
  riscv: Introduce CONFIG_RELOCATABLE
  riscv: Move .rela.dyn outside of init to avoid empty relocations
  riscv: Prepare EFI header for relocatable kernels
  riscv: Unconditionnally select KASAN_VMALLOC if KASAN
  riscv: Fix ptdump when KASAN is enabled
  riscv: Fix EFI stub usage of KASAN instrumented strcmp function
  riscv: Move DTB_EARLY_BASE_VA to the kernel address space
  riscv: Rework kasan population functions
  riscv: Split early and final KASAN population functions
  riscv: Use PUD/P4D/PGD pages for the linear mapping
  riscv: Move the linear mapping creation in its own function
  riscv: Get rid of riscv_pfn_base variable
  ...
2023-04-28 16:55:39 -07:00
Linus Torvalds
cb6fe2ceb6 Devicetree updates for v6.4, part 2:
- First part of DT header detangling dropping cpu.h from of_device.h
   and replacing some includes with forward declarations. A handful of
   drivers needed some adjustment to their includes as a result.
 
 - Refactor of_device.h to be used by bus drivers rather than various
   device drivers. This moves non-bus related functions out of
   of_device.h. The end goal is for of_platform.h and of_device.h to stop
   including each other.
 
 - Refactor open coded parsing of "ranges" in some bus drivers to use DT
   address parsing functions
 
 - Add some new address parsing functions of_property_read_reg(),
   of_range_count(), and of_range_to_resource() in preparation to convert
   more open coded parsing of DT addresses to use them.
 
 - Treewide clean-ups to use of_property_read_bool() and
   of_property_present() as appropriate. The ones here are the ones
   that didn't get picked up elsewhere.
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Merge tag 'devicetree-for-6.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull more devicetree updates from Rob Herring:

 - First part of DT header detangling dropping cpu.h from of_device.h
   and replacing some includes with forward declarations. A handful of
   drivers needed some adjustment to their includes as a result.

 - Refactor of_device.h to be used by bus drivers rather than various
   device drivers. This moves non-bus related functions out of
   of_device.h. The end goal is for of_platform.h and of_device.h to
   stop including each other.

 - Refactor open coded parsing of "ranges" in some bus drivers to use DT
   address parsing functions

 - Add some new address parsing functions of_property_read_reg(),
   of_range_count(), and of_range_to_resource() in preparation to
   convert more open coded parsing of DT addresses to use them.

 - Treewide clean-ups to use of_property_read_bool() and
   of_property_present() as appropriate. The ones here are the ones that
   didn't get picked up elsewhere.

* tag 'devicetree-for-6.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (34 commits)
  bus: tegra-gmi: Replace of_platform.h with explicit includes
  hte: Use of_property_present() for testing DT property presence
  w1: w1-gpio: Use of_property_read_bool() for boolean properties
  virt: fsl: Use of_property_present() for testing DT property presence
  soc: fsl: Use of_property_present() for testing DT property presence
  sbus: display7seg: Use of_property_read_bool() for boolean properties
  sparc: Use of_property_read_bool() for boolean properties
  sparc: Use of_property_present() for testing DT property presence
  bus: mvebu-mbus: Remove open coded "ranges" parsing
  of/address: Add of_property_read_reg() helper
  of/address: Add of_range_count() helper
  of/address: Add support for 3 address cell bus
  of/address: Add of_range_to_resource() helper
  of: unittest: Add bus address range parsing tests
  of: Drop cpu.h include from of_device.h
  OPP: Adjust includes to remove of_device.h
  irqchip: loongson-eiointc: Add explicit include for cpuhotplug.h
  cpuidle: Adjust includes to remove of_device.h
  cpufreq: sun50i: Add explicit include for cpu.h
  cpufreq: Adjust includes to remove of_device.h
  ...
2023-04-27 10:09:05 -07:00
Alexandre Ghiti
f158162607
riscv: Do not set initial_boot_params to the linear address of the dtb
early_init_dt_verify() is already called in parse_dtb() and since the dtb
address does not change anymore (it is now in the fixmap region), no need
to reset initial_boot_params by calling early_init_dt_verify() again.

Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20230329081932.79831-3-alexghiti@rivosinc.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-13 18:14:33 -07:00
Alexandre Ghiti
ef69d2559f
riscv: Move early dtb mapping into the fixmap region
riscv establishes 2 virtual mappings:

- early_pg_dir maps the kernel which allows to discover the system
  memory
- swapper_pg_dir installs the final mapping (linear mapping included)

We used to map the dtb in early_pg_dir using DTB_EARLY_BASE_VA, and this
mapping was not carried over in swapper_pg_dir. It happens that
early_init_fdt_scan_reserved_mem() must be called before swapper_pg_dir is
setup otherwise we could allocate reserved memory defined in the dtb.
And this function initializes reserved_mem variable with addresses that
lie in the early_pg_dir dtb mapping: when those addresses are reused
with swapper_pg_dir, this mapping does not exist and then we trap.

The previous "fix" was incorrect as early_init_fdt_scan_reserved_mem()
must be called before swapper_pg_dir is set up otherwise we could
allocate in reserved memory defined in the dtb.

So move the dtb mapping in the fixmap region which is established in
early_pg_dir and handed over to swapper_pg_dir.

Fixes: 922b0375fc ("riscv: Fix memblock reservation for device tree blob")
Fixes: 8f3a2b4a96 ("RISC-V: Move DT mapping outof fixmap")
Fixes: 50e63dd8ed ("riscv: fix reserved memory setup")
Reported-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/all/f8e67f82-103d-156c-deb0-d6d6e2756f5e@microchip.com/
Signed-off-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230329081932.79831-2-alexghiti@rivosinc.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-13 18:14:26 -07:00
Rob Herring
a0418108d7 riscv: Add explicit include for cpu.h
Removing the include of cpu.h from of_device.h (included by
of_platform.h) causes an error in setup.c:

arch/riscv/kernel/setup.c:313:22: error: arithmetic on a pointer to an incomplete type 'typeof(struct cpu)' (aka 'struct cpu')

The of_platform.h header is not necessary either, so it can be dropped.

Link: https://lore.kernel.org/r/20230329-dt-cpu-header-cleanups-v1-8-581e2605fe47@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
2023-04-13 17:46:34 -05:00
Andrew Jones
7ea5a73617
RISC-V: Add Zicboz detection and block size parsing
Parse "riscv,cboz-block-size" from the DT by piggybacking on Zicbom's
riscv_init_cbom_blocksize(). Additionally check the DT for the presence
of the "zicboz" extension and, when it's present, validate the parsed
cboz block size as we do Zicbom's cbom block size with
riscv_isa_extension_check().

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230224162631.405473-5-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-03-14 21:26:04 -07:00
Jisheng Zhang
abcc445acd
riscv: move riscv_noncoherent_supported() out of ZICBOM probe
It's a bit weird to call riscv_noncoherent_supported() each time when
insmoding a module. Move the calling out of feature patch func.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230128172856.3814-2-jszhang@kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-01-31 23:29:33 -08:00
Björn Töpel
6fdd5d2f8c
riscv: mm: Proper page permissions after initmem free
64-bit RISC-V kernels have the kernel image mapped separately to alias
the linear map. The linear map and the kernel image map are documented
as "direct mapping" and "kernel" respectively in [1].

At image load time, the linear map corresponding to the kernel image
is set to PAGE_READ permission, and the kernel image map is set to
PAGE_READ|PAGE_EXEC.

When the initmem is freed, the pages in the linear map should be
restored to PAGE_READ|PAGE_WRITE, whereas the corresponding pages in
the kernel image map should be restored to PAGE_READ, by removing the
PAGE_EXEC permission.

This is not the case. For 64-bit kernels, only the linear map is
restored to its proper page permissions at initmem free, and not the
kernel image map.

In practise this results in that the kernel can potentially jump to
dead __init code, and start executing invalid instructions, without
getting an exception.

Restore the freed initmem properly, by setting both the kernel image
map to the correct permissions.

[1] Documentation/riscv/vm-layout.rst

Fixes: e5c35fa040 ("riscv: Map the kernel with correct permissions the first time")
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alex@ghiti.fr>
Tested-by: Alexandre Ghiti <alex@ghiti.fr>
Link: https://lore.kernel.org/r/20221115090641.258476-1-bjorn@kernel.org
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-11-29 18:54:30 -08:00
Conor Dooley
50e63dd8ed
riscv: fix reserved memory setup
Currently, RISC-V sets up reserved memory using the "early" copy of the
device tree. As a result, when trying to get a reserved memory region
using of_reserved_mem_lookup(), the pointer to reserved memory regions
is using the early, pre-virtual-memory address which causes a kernel
panic when trying to use the buffer's name:

 Unable to handle kernel paging request at virtual address 00000000401c31ac
 Oops [#1]
 Modules linked in:
 CPU: 0 PID: 0 Comm: swapper Not tainted 6.0.0-rc1-00001-g0d9d6953d834 #1
 Hardware name: Microchip PolarFire-SoC Icicle Kit (DT)
 epc : string+0x4a/0xea
  ra : vsnprintf+0x1e4/0x336
 epc : ffffffff80335ea0 ra : ffffffff80338936 sp : ffffffff81203be0
  gp : ffffffff812e0a98 tp : ffffffff8120de40 t0 : 0000000000000000
  t1 : ffffffff81203e28 t2 : 7265736572203a46 s0 : ffffffff81203c20
  s1 : ffffffff81203e28 a0 : ffffffff81203d22 a1 : 0000000000000000
  a2 : ffffffff81203d08 a3 : 0000000081203d21 a4 : ffffffffffffffff
  a5 : 00000000401c31ac a6 : ffff0a00ffffff04 a7 : ffffffffffffffff
  s2 : ffffffff81203d08 s3 : ffffffff81203d00 s4 : 0000000000000008
  s5 : ffffffff000000ff s6 : 0000000000ffffff s7 : 00000000ffffff00
  s8 : ffffffff80d9821a s9 : ffffffff81203d22 s10: 0000000000000002
  s11: ffffffff80d9821c t3 : ffffffff812f3617 t4 : ffffffff812f3617
  t5 : ffffffff812f3618 t6 : ffffffff81203d08
 status: 0000000200000100 badaddr: 00000000401c31ac cause: 000000000000000d
 [<ffffffff80338936>] vsnprintf+0x1e4/0x336
 [<ffffffff80055ae2>] vprintk_store+0xf6/0x344
 [<ffffffff80055d86>] vprintk_emit+0x56/0x192
 [<ffffffff80055ed8>] vprintk_default+0x16/0x1e
 [<ffffffff800563d2>] vprintk+0x72/0x80
 [<ffffffff806813b2>] _printk+0x36/0x50
 [<ffffffff8068af48>] print_reserved_mem+0x1c/0x24
 [<ffffffff808057ec>] paging_init+0x528/0x5bc
 [<ffffffff808031ae>] setup_arch+0xd0/0x592
 [<ffffffff8080070e>] start_kernel+0x82/0x73c

early_init_fdt_scan_reserved_mem() takes no arguments as it operates on
initial_boot_params, which is populated by early_init_dt_verify(). On
RISC-V, early_init_dt_verify() is called twice. Once, directly, in
setup_arch() if CONFIG_BUILTIN_DTB is not enabled and once indirectly,
very early in the boot process, by parse_dtb() when it calls
early_init_dt_scan_nodes().

This first call uses dtb_early_va to set initial_boot_params, which is
not usable later in the boot process when
early_init_fdt_scan_reserved_mem() is called. On arm64 for example, the
corresponding call to early_init_dt_scan_nodes() uses fixmap addresses
and doesn't suffer the same fate.

Move early_init_fdt_scan_reserved_mem() further along the boot sequence,
after the direct call to early_init_dt_verify() in setup_arch() so that
the names use the correct virtual memory addresses. The above supposed
that CONFIG_BUILTIN_DTB was not set, but should work equally in the case
where it is - unflatted_and_copy_device_tree() also updates
initial_boot_params.

Reported-by: Valentina Fernandez <valentina.fernandezalanis@microchip.com>
Reported-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Link: https://lore.kernel.org/linux-riscv/f8e67f82-103d-156c-deb0-d6d6e2756f5e@microchip.com/
Fixes: 922b0375fc ("riscv: Fix memblock reservation for device tree blob")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Tested-by: Evgenii Shatokhin <e.shatokhin@yadro.com>
Link: https://lore.kernel.org/r/20221107151524.3941467-1-conor.dooley@microchip.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-11-10 14:46:33 -08:00
Wenting Zhang
10f6913c54
riscv: always honor the CONFIG_CMDLINE_FORCE when parsing dtb
When CONFIG_CMDLINE_FORCE is enabled, cmdline provided by
CONFIG_CMDLINE are always used. This allows CONFIG_CMDLINE to be
used regardless of the result of device tree scanning.

This especially fixes the case where a device tree without the
chosen node is supplied to the kernel. In such cases,
early_init_dt_scan would return true. But inside
early_init_dt_scan_chosen, the cmdline won't be updated as there
is no chosen node in the device tree. As a result, CONFIG_CMDLINE
is not copied into boot_command_line even if CONFIG_CMDLINE_FORCE
is enabled. This commit allows properly update boot_command_line
in this situation.

Fixes: 8fd6e05c74 ("arch: riscv: support kernel command line forcing when no DTB passed")
Signed-off-by: Wenting Zhang <zephray@outlook.com>
Reviewed-by: Björn Töpel <bjorn@kernel.org>
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/PSBPR04MB399135DFC54928AB958D0638B1829@PSBPR04MB3991.apcprd04.prod.outlook.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-10-11 19:53:08 -07:00
Palmer Dabbelt
8f7e001e03
RISC-V: Clean up the Zicbom block size probing
This fixes two issues: I truncated the warning's hart ID when porting to
the 64-bit hart ID code, and the original code's warning handling could
fire on an uninitialized hart ID.

The biggest change here is that riscv_cbom_block_size is no longer
initialized, as IMO the default isn't sane: there's nothing in the ISA
that mandates any specific cache block size, so falling back to one will
just silently produce the wrong answer on some systems.  This also
changes the probing order so the cache block size is known before
enabling Zicbom support.

CC: stable@vger.kernel.org
CC: Andrew Jones <ajones@ventanamicro.com>
CC: Heiko Stuebner <heiko@sntech.de>
CC: Atish Patra <atishp@rivosinc.com>
Fixes: 3aefb2ee5b ("riscv: implement Zicbom-based CMO instructions + the t-head variant")
Fixes: 1631ba1259 ("riscv: Add support for non-coherent devices using zicbom extension")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
[Conor: fixed the redefinition errors]
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220912224800.998121-1-mail@conchuod.ie
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-09-13 02:06:11 -07:00
Heiko Stuebner
1631ba1259
riscv: Add support for non-coherent devices using zicbom extension
The Zicbom ISA-extension was ratified in november 2021
and introduces instructions for dcache invalidate, clean
and flush operations.

Implement cache management operations for non-coherent devices
based on them.

Of course not all cores will support this, so implement an
alternative-based mechanism that replaces empty instructions
with ones done around Zicbom instructions.

As discussed in previous versions, assume the platform
being coherent by default so that non-coherent devices need
to get marked accordingly by firmware.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20220706231536.2041855-4-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-07-28 15:30:51 -07:00
Xianting Tian
e61bf5c071
RISC-V: Mark IORESOURCE_EXCLUSIVE for reserved mem instead of IORESOURCE_BUSY
Commit 00ab027a3b ("RISC-V: Add kernel image sections to the resource tree")
marked IORESOURCE_BUSY for reserved memory, which caused resource map
failed in subsequent operations of related driver, so remove the
IORESOURCE_BUSY flag. In order to prohibit userland mapping reserved
memory, mark IORESOURCE_EXCLUSIVE for it.

The code to reproduce the issue,
dts:
        mem0: memory@a0000000 {
                reg = <0x0 0xa0000000 0 0x1000000>;
                no-map;
        };

        &test {
                status = "okay";
                memory-region = <&mem0>;
        };

code:
        np = of_parse_phandle(pdev->dev.of_node, "memory-region", 0);
        ret = of_address_to_resource(np, 0, &r);
        base = devm_ioremap_resource(&pdev->dev, &r);
        // base = -EBUSY

Fixes: 00ab027a3b ("RISC-V: Add kernel image sections to the resource tree")
Reported-by: Huaming Jiang <jianghuaming.jhm@alibaba-inc.com>
Reviewed-by: Guo Ren <guoren@kernel.org>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Co-developed-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220518013428.1338983-1-xianting.tian@linux.alibaba.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-06-01 22:03:50 -07:00
Heiko Stuebner
ffb0b0afbd
riscv: move boot alternatives to after fill_hwcap
Move the application of boot alternatives to after the hw-capabilities
are populated. This allows to check for available extensions when
determining which alternatives to apply and also makes it actually
work if CONFIG_SMP is disabled for whatever reason.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Philipp Tomsich <philipp.tomsich@vrull.eu>
Reviewed-by: Guo Ren <guoren@kernel.org>
Link: https://lore.kernel.org/r/20220511192921.2223629-8-heiko@sntech.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-05-11 21:36:32 -07:00
David Hildenbrand
2848a28b0a drivers/base/node: consolidate node device subsystem initialization in node_dev_init()
...  and call node_dev_init() after memory_dev_init() from driver_init(),
so before any of the existing arch/subsys calls.  All online nodes should
be known at that point: early during boot, arch code determines node and
zone ranges and sets the relevant nodes online; usually this happens in
setup_arch().

This is in line with memory_dev_init(), which initializes the memory
device subsystem and creates all memory block devices.

Similar to memory_dev_init(), panic() if anything goes wrong, we don't
want to continue with such basic initialization errors.

The important part is that node_dev_init() gets called after
memory_dev_init() and after cpu_dev_init(), but before any of the relevant
archs call register_cpu() to register the new cpu device under the node
device.  The latter should be the case for the current users of
topology_init().

Link: https://lkml.kernel.org/r/20220203105212.30385-1-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Tested-by: Anatoly Pugachev <matorola@gmail.com> (sparc64)
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:10 -07:00
Atish Patra
26fb751ca3
RISC-V: Do not use cpumask data structure for hartid bitmap
Currently, SBI APIs accept a hartmask that is generated from struct
cpumask. Cpumask data structure can hold upto NR_CPUs value. Thus, it
is not the correct data structure for hartids as it can be higher
than NR_CPUs for platforms with sparse or discontguous hartids.

Remove all association between hartid mask and struct cpumask.

Reviewed-by: Anup Patel <anup@brainfault.org> (For Linux RISC-V changes)
Acked-by: Anup Patel <anup@brainfault.org> (For KVM RISC-V changes)
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-20 09:27:22 -08:00
Sean Christopherson
869c706092
RISC-V: Use common riscv_cpuid_to_hartid_mask() for both SMP=y and SMP=n
Use what is currently the SMP=y version of riscv_cpuid_to_hartid_mask()
for both SMP=y and SMP=n to fix a build failure with KVM=m and SMP=n due
to boot_cpu_hartid not being exported.  This also fixes a second bug
where the SMP=n version assumes the sole CPU in the system is in the
incoming mask, which may not hold true in kvm_riscv_vcpu_sbi_ecall() if
the KVM guest VM has multiple vCPUs (on a SMP=n system).

Fixes: 1ef46c231d ("RISC-V: Implement new SBI v0.2 extensions")
Reported-by: Adam Borowski <kilobyte@angband.pl>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-01-09 12:13:31 -08:00
Mike Rapoport
4421cca0a3 memblock: use memblock_free for freeing virtual pointers
Rename memblock_free_ptr() to memblock_free() and use memblock_free()
when freeing a virtual pointer so that memblock_free() will be a
counterpart of memblock_alloc()

The callers are updated with the below semantic patch and manual
addition of (void *) casting to pointers that are represented by
unsigned long variables.

    @@
    identifier vaddr;
    expression size;
    @@
    (
    - memblock_phys_free(__pa(vaddr), size);
    + memblock_free(vaddr, size);
    |
    - memblock_free_ptr(vaddr, size);
    + memblock_free(vaddr, size);
    )

[sfr@canb.auug.org.au: fixup]
  Link: https://lkml.kernel.org/r/20211018192940.3d1d532f@canb.auug.org.au

Link: https://lkml.kernel.org/r/20210930185031.18648-7-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:41 -07:00
Mike Rapoport
3ecc68349b memblock: rename memblock_free to memblock_phys_free
Since memblock_free() operates on a physical range, make its name
reflect it and rename it to memblock_phys_free(), so it will be a
logical counterpart to memblock_phys_alloc().

The callers are updated with the below semantic patch:

    @@
    expression addr;
    expression size;
    @@
    - memblock_free(addr, size);
    + memblock_phys_free(addr, size);

Link: https://lkml.kernel.org/r/20210930185031.18648-6-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Juergen Gross <jgross@suse.com>
Cc: Shahab Vahedi <Shahab.Vahedi@synopsys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:41 -07:00
Linus Torvalds
063df71a57 RISC-V Patches for the 5.15 Merge Window, Part 1
* Support for PC-relative instructions (auipc and branches) in kprobes.
 * Support for forced IRQ threading.
 * Support for the hlt/nohlt kernel command line options, via the generic
   idle loop.
 * Support for showing the edge/level triggered behavior of interrupts in
   /proc/interrupts.
 * A handful of cleanups to our address mapping mechanisms.
 * Support for allocating gigantic hugepages via CMA.
 * Support for the undefined behavior sanitizer.
 * A handful of cleanups to the VDSO that allow the kernel to build with
   LLD.
 * Support for hugepage migration.
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Merge tag 'riscv-for-linus-5.15-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - support PC-relative instructions (auipc and branches) in kprobes

 - support for forced IRQ threading

 - support for the hlt/nohlt kernel command line options, via the
   generic idle loop

 - show the edge/level triggered behavior of interrupts
   in /proc/interrupts

 - a handful of cleanups to our address mapping mechanisms

 - support for allocating gigantic hugepages via CMA

 - support for the undefined behavior sanitizer (UBSAN)

 - a handful of cleanups to the VDSO that allow the kernel to build with
   LLD.

 - support for hugepage migration

* tag 'riscv-for-linus-5.15-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (21 commits)
  riscv: add support for hugepage migration
  RISC-V: Fix VDSO build for !MMU
  riscv: use strscpy to replace strlcpy
  riscv: explicitly use symbol offsets for VDSO
  riscv: Enable Undefined Behavior Sanitizer UBSAN
  riscv: Keep the riscv Kconfig selects sorted
  riscv: Support allocating gigantic hugepages using CMA
  riscv: fix the global name pfn_base confliction error
  riscv: Move early fdt mapping creation in its own function
  riscv: Simplify BUILTIN_DTB device tree mapping handling
  riscv: Use __maybe_unused instead of #ifdefs around variable declarations
  riscv: Get rid of map_size parameter to create_kernel_page_table
  riscv: Introduce va_kernel_pa_offset for 32-bit kernel
  riscv: Optimize kernel virtual address conversion macro
  dt-bindings: riscv: add starfive jh7100 bindings
  riscv: Enable GENERIC_IRQ_SHOW_LEVEL
  riscv: Enable idle generic idle loop
  riscv: Allow forced irq threading
  riscv: Implement thread_struct whitelist for hardened usercopy
  riscv: kprobes: implement the branch instructions
  ...
2021-09-05 11:31:23 -07:00
Jason Wang
803930ee35
riscv: use strscpy to replace strlcpy
The strlcpy should not be used because it doesn't limit the source
length. As linus says, it's a completely useless function if you
can't implicitly trust the source string - but that is almost always
why people think they should use it! All in all the BSD function
will lead some potential bugs.

But the strscpy doesn't require reading memory from the src string
beyond the specified "count" bytes, and since the return value is
easier to error-check than strlcpy()'s. In addition, the implementation
is robust to the string changing out from underneath it, unlike the
current strlcpy() implementation.

Thus, We prefer using strscpy instead of strlcpy.

Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-25 21:52:47 -07:00
Petr Pavlu
aa3e1ba32e
riscv: Fix a number of free'd resources in init_resources()
Function init_resources() allocates a boot memory block to hold an array of
resources which it adds to iomem_resource. The array is filled in from its
end and the function then attempts to free any unused memory at the
beginning. The problem is that size of the unused memory is incorrectly
calculated and this can result in releasing memory which is in use by
active resources. Their data then gets corrupted later when the memory is
reused by a different part of the system.

Fix the size of the released memory to correctly match the number of unused
resource entries.

Fixes: ffe0e52612 ("RISC-V: Improve init_resources()")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Nick Kossifidis <mick@ics.forth.gr>
Tested-by: Sunil V L <sunilvl@ventanamicro.com>
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-08-20 10:15:51 -07:00
Linus Torvalds
9b76d71fa8 RISC-V Patches for the 5.14 Merge Window, Part 1
In addition to We have a handful of new features for 5.14:
 
 * Support for transparent huge pages.
 * Support for generic PCI resources mapping.
 * Support for the mem= kernel parameter.
 * Support for KFENCE.
 * A handful of fixes to avoid W+X mappings in the kernel.
 * Support for VMAP_STACK based overflow detection.
 * An optimized copy_{to,from}_user.
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Merge tag 'riscv-for-linus-5.14-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:
 "We have a handful of new features for 5.14:

   - Support for transparent huge pages.

   - Support for generic PCI resources mapping.

   - Support for the mem= kernel parameter.

   - Support for KFENCE.

   - A handful of fixes to avoid W+X mappings in the kernel.

   - Support for VMAP_STACK based overflow detection.

   - An optimized copy_{to,from}_user"

* tag 'riscv-for-linus-5.14-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (37 commits)
  riscv: xip: Fix duplicate included asm/pgtable.h
  riscv: Fix PTDUMP output now BPF region moved back to module region
  riscv: __asm_copy_to-from_user: Optimize unaligned memory access and pipeline stall
  riscv: add VMAP_STACK overflow detection
  riscv: ptrace: add argn syntax
  riscv: mm: fix build errors caused by mk_pmd()
  riscv: Introduce structure that group all variables regarding kernel mapping
  riscv: Map the kernel with correct permissions the first time
  riscv: Introduce set_kernel_memory helper
  riscv: Enable KFENCE for riscv64
  RISC-V: Use asm-generic for {in,out}{bwlq}
  riscv: add ASID-based tlbflushing methods
  riscv: pass the mm_struct to __sbi_tlb_flush_range
  riscv: Add mem kernel parameter support
  riscv: Simplify xip and !xip kernel address conversion macros
  riscv: Remove CONFIG_PHYS_RAM_BASE_FIXED
  riscv: Only initialize swiotlb when necessary
  riscv: fix typo in init.c
  riscv: Cleanup unused functions
  riscv: mm: Use better bitmap_zalloc()
  ...
2021-07-09 10:36:29 -07:00
Kefeng Wang
723a42f4f6 riscv: convert to setup_initial_init_mm()
Use setup_initial_init_mm() helper to simplify code.

Link: https://lkml.kernel.org/r/20210608083418.137226-13-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
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
Palmer Dabbelt
01112e5e20
Merge branch 'riscv-wx-mappings' into for-next
This contains both the short-term fix for the W+X boot mappings and the
larger cleanup.

* riscv-wx-mappings:
  riscv: Map the kernel with correct permissions the first time
  riscv: Introduce set_kernel_memory helper
  riscv: Simplify xip and !xip kernel address conversion macros
  riscv: Remove CONFIG_PHYS_RAM_BASE_FIXED
  riscv: mm: Fix W+X mappings at boot
2021-06-30 21:50:32 -07:00
Alexandre Ghiti
e5c35fa040
riscv: Map the kernel with correct permissions the first time
For 64-bit kernels, we map all the kernel with write and execute
permissions and afterwards remove writability from text and executability
from data.

For 32-bit kernels, the kernel mapping resides in the linear mapping, so we
map all the linear mapping as writable and executable and afterwards we
remove those properties for unused memory and kernel mapping as
described above.

Change this behavior to directly map the kernel with correct permissions
and avoid going through the whole mapping to fix the permissions.

At the same time, this fixes an issue introduced by commit 2bfc6cd81b
("riscv: Move kernel mapping outside of linear mapping") as reported
here https://github.com/starfive-tech/linux/issues/17.

Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-06-30 21:18:58 -07:00
Kefeng Wang
ce3aca0465
riscv: Only initialize swiotlb when necessary
The SWIOTLB buffer is not needed unless the physical address space
is beyond the limit of dma, only initialize swiotlb when swiotlb_force
is true or not all system memory is DMA-able.

Also move the swiotlb_init() into mem_init().

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-06-11 13:42:26 -07:00
Wende Tan
da2d48808f
RISC-V: Fix memblock_free() usages in init_resources()
`memblock_free()` takes a physical address as its first argument.
Fix the wrong usages in `init_resources()`.

Fixes: ffe0e52612 ("RISC-V: Improve init_resources()")
Fixes: 797f0375dd ("RISC-V: Do not allocate memblock while iterating reserved memblocks")
Signed-off-by: Wende Tan <twd2.me@gmail.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-06-01 21:16:42 -07:00
Kefeng Wang
f842f5ff6a
riscv: Move setup_bootmem into paging_init
Make setup_bootmem() static.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-25 22:50:50 -07:00
Geert Uytterhoeven
8d91b09733
riscv: Consistify protect_kernel_linear_mapping_text_rodata() use
The various uses of protect_kernel_linear_mapping_text_rodata() are
not consistent:
  - Its definition depends on "64BIT && !XIP_KERNEL",
  - Its forward declaration depends on MMU,
  - Its single caller depends on "STRICT_KERNEL_RWX && 64BIT && MMU &&
    !XIP_KERNEL".

Fix this by settling on the dependencies of the caller, which can be
simplified as STRICT_KERNEL_RWX depends on "MMU && !XIP_KERNEL".
Provide a dummy definition, as the caller is protected by
"IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)" instead of "#ifdef
CONFIG_STRICT_KERNEL_RWX".

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Alexandre Ghiti <alex@ghiti.fr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-05-06 09:40:15 -07:00
Vitaly Wool
44c9225729
RISC-V: enable XIP
Introduce XIP (eXecute In Place) support for RISC-V platforms.
It allows code to be executed directly from non-volatile storage
directly addressable by the CPU, such as QSPI NOR flash which can
be found on many RISC-V platforms. This makes way for significant
optimization of RAM footprint. The XIP kernel is not compressed
since it has to run directly from flash, so it will occupy more
space on the non-volatile storage. The physical flash address used
to link the kernel object files and for storing it has to be known
at compile time and is represented by a Kconfig option.

XIP on RISC-V will for the time being only work on MMU-enabled
kernels.

Signed-off-by: Vitaly Wool <vitaly.wool@konsulko.com>
[Alex: Rebase on top of "Move kernel mapping outside the linear mapping" ]
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
[Palmer: disable XIP for allyesconfig]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26 08:31:28 -07:00
Nick Kossifidis
5640975003
RISC-V: Add crash kernel support
This patch allows Linux to act as a crash kernel for use with
kdump. Userspace will let the crash kernel know about the
memory region it can use through linux,usable-memory property
on the /memory node (overriding its reg property), and about the
memory region where the elf core header of the previous kernel
is saved, through a reserved-memory node with a compatible string
of "linux,elfcorehdr". This approach is the least invasive and
re-uses functionality already present.

I tested this on riscv64 qemu and it works as expected, you
may test it by retrieving the dmesg of the previous kernel
through /proc/vmcore, using the vmcore-dmesg utility from
kexec-tools.

Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26 08:25:24 -07:00
Nick Kossifidis
e53d28180d
RISC-V: Add kdump support
This patch adds support for kdump, the kernel will reserve a
region for the crash kernel and jump there on panic. In order
for userspace tools (kexec-tools) to prepare the crash kernel
kexec image, we also need to expose some information on
/proc/iomem for the memory regions used by the kernel and for
the region reserved for crash kernel. Note that on userspace
the device tree is used to determine the system's memory
layout so the "System RAM" on /proc/iomem is ignored.

I tested this on riscv64 qemu and works as expected, you may
test it by triggering a crash through /proc/sysrq_trigger:

echo c > /proc/sysrq_trigger

Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26 08:25:23 -07:00
Nick Kossifidis
ffe0e52612
RISC-V: Improve init_resources()
The kernel region is always present and we know where it is, no need to
look for it inside the loop, just ignore it like the rest of the
reserved regions within system's memory.

Additionally, we don't need to call memblock_free inside the loop, as if
called it'll split the region of pre-allocated resources in two parts,
messing things up, just re-use the previous pre-allocated resource and
free any unused resources after both loops finish.

Signed-off-by: Nick Kossifidis <mick@ics.forth.gr>
[Palmer: commit text]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26 08:25:22 -07:00
Alexandre Ghiti
2bfc6cd81b
riscv: Move kernel mapping outside of linear mapping
This is a preparatory patch for relocatable kernel and sv48 support.

The kernel used to be linked at PAGE_OFFSET address therefore we could use
the linear mapping for the kernel mapping. But the relocated kernel base
address will be different from PAGE_OFFSET and since in the linear mapping,
two different virtual addresses cannot point to the same physical address,
the kernel mapping needs to lie outside the linear mapping so that we don't
have to copy it at the same physical offset.

The kernel mapping is moved to the last 2GB of the address space, BPF
is now always after the kernel and modules use the 2GB memory range right
before the kernel, so BPF and modules regions do not overlap. KASLR
implementation will simply have to move the kernel in the last 2GB range
and just take care of leaving enough space for BPF.

In addition, by moving the kernel to the end of the address space, both
sv39 and sv48 kernels will be exactly the same without needing to be
relocated at runtime.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
[Palmer: Squash the STRICT_RWX fix, and a !MMU fix]
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-04-26 08:25:04 -07:00