riscv: Properly export reserved regions in /proc/iomem

The /proc/iomem represents the kernel's memory map. Regions marked
with "Reserved" tells the user that the range should not be tampered
with. K

riscv: Properly export reserved regions in /proc/iomem

The /proc/iomem represents the kernel's memory map. Regions marked
with "Reserved" tells the user that the range should not be tampered
with. Kexec-tools, when using the older kexec_load syscall relies on
the "Reserved" regions to build the memory segments, that will be the
target of the new kexec'd kernel.

The RISC-V port tries to expose all reserved regions to userland, but
some regions were not properly exposed: Regions that resided in both
the "regular" and reserved memory block, e.g. the EFI Memory Map. A
missing entry could result in reserved memory being overwritten.

It turns out, that arm64, and loongarch had a similar issue a while
back:

commit d91680e687f4 ("arm64: Fix /proc/iomem for reserved but not memory regions")
commit 50d7ba36b916 ("arm64: export memblock_reserve()d regions via /proc/iomem")

Similar to the other ports, resolve the issue by splitting the regions
in an arch initcall, since we need a working allocator.

Fixes: ffe0e5261268 ("RISC-V: Improve init_resources()")
Signed-off-by: Björn Töpel <[email protected]>
Reviewed-by: Alexandre Ghiti <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Ghiti <[email protected]>

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riscv: remove redundant CMDLINE_FORCE check

Drop redundant CMDLINE_FORCE check as it's already done in
function early_init_dt_scan_chosen().

Signed-off-by: Zixian Zeng <[email protected]>
R

riscv: remove redundant CMDLINE_FORCE check

Drop redundant CMDLINE_FORCE check as it's already done in
function early_init_dt_scan_chosen().

Signed-off-by: Zixian Zeng <[email protected]>
Reviewed-by: Alexandre Ghiti <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Alexandre Ghiti <[email protected]>

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riscv: signal: fix signal_minsigstksz

The init_rt_signal_env() funciton is called before the alternative patch
is applied, so using the alternative-related API to check the availability
of an extens

riscv: signal: fix signal_minsigstksz

The init_rt_signal_env() funciton is called before the alternative patch
is applied, so using the alternative-related API to check the availability
of an extension within this function doesn't have the intended effect.
This patch reorders the init_rt_signal_env() and apply_boot_alternatives()
to get the correct signal_minsigstksz.

Fixes: e92f469b0771 ("riscv: signal: Report signal frame size to userspace via auxv")
Signed-off-by: Yong-Xuan Wang <[email protected]>
Reviewed-by: Zong Li <[email protected]>
Reviewed-by: Andy Chiu <[email protected]>
Reviewed-by: Alexandre Ghiti <[email protected]>
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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mm/memblock: add memblock_alloc_or_panic interface

Before SLUB initialization, various subsystems used memblock_alloc to
allocate memory. In most cases, when memory allocation fails, an
immediate p

mm/memblock: add memblock_alloc_or_panic interface

Before SLUB initialization, various subsystems used memblock_alloc to
allocate memory. In most cases, when memory allocation fails, an
immediate panic is required. To simplify this behavior and reduce
repetitive checks, introduce `memblock_alloc_or_panic`. This function
ensures that memory allocation failures result in a panic automatically,
improving code readability and consistency across subsystems that require
this behavior.

[[email protected]: arch/s390: save_area_alloc default failure behavior changed to panic]
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lore.kernel.org/lkml/[email protected]/
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Guo Weikang <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> [m68k]
Reviewed-by: Alexander Gordeev <[email protected]> [s390]
Acked-by: Mike Rapoport (Microsoft) <[email protected]>
Cc: Alexander Gordeev <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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riscv: Fix wrong usage of __pa() on a fixmap address

riscv uses fixmap addresses to map the dtb so we can't use __pa() which
is reserved for linear mapping addresses.

Fixes: b2473a359763 ("of/fdt:

riscv: Fix wrong usage of __pa() on a fixmap address

riscv uses fixmap addresses to map the dtb so we can't use __pa() which
is reserved for linear mapping addresses.

Fixes: b2473a359763 ("of/fdt: add dt_phys arg to early_init_dt_scan and early_init_dt_verify")
Signed-off-by: Alexandre Ghiti <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: [email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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riscv: Add qspinlock support

In order to produce a generic kernel, a user can select
CONFIG_COMBO_SPINLOCKS which will fallback at runtime to the ticket
spinlock implementation if Zabha or Ziccrse a

riscv: Add qspinlock support

In order to produce a generic kernel, a user can select
CONFIG_COMBO_SPINLOCKS which will fallback at runtime to the ticket
spinlock implementation if Zabha or Ziccrse are not present.

Note that we can't use alternatives here because the discovery of
extensions is done too late and we need to start with the qspinlock
implementation because the ticket spinlock implementation would pollute
the spinlock value, so let's use static keys.

This is largely based on Guo's work and Leonardo reviews at [1].

Link: https://lore.kernel.org/linux-riscv/[email protected]/ [1]
Signed-off-by: Guo Ren <[email protected]>
Signed-off-by: Alexandre Ghiti <[email protected]>
Reviewed-by: Andrea Parri <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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of/fdt: add dt_phys arg to early_init_dt_scan and early_init_dt_verify

__pa() is only intended to be used for linear map addresses and using
it for initial_boot_params which is in fixmap for arm64

of/fdt: add dt_phys arg to early_init_dt_scan and early_init_dt_verify

__pa() is only intended to be used for linear map addresses and using
it for initial_boot_params which is in fixmap for arm64 will give an
incorrect value. Hence save the physical address when it is known at
boot time when calling early_init_dt_scan for arm64 and use it at kexec
time instead of converting the virtual address using __pa().

Note that arm64 doesn't need the FDT region reserved in the DT as the
kernel explicitly reserves the passed in FDT. Therefore, only a debug
warning is fixed with this change.

Reported-by: Breno Leitao <[email protected]>
Suggested-by: Mark Rutland <[email protected]>
Signed-off-by: Usama Arif <[email protected]>
Fixes: ac10be5cdbfa ("arm64: Use common of_kexec_alloc_and_setup_fdt()")
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[email protected]>

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ACPI: RISCV: Add NUMA support based on SRAT and SLIT

Add acpi_numa.c file to enable parse NUMA information from
ACPI SRAT and SLIT tables. SRAT table provide CPUs(Hart) and
memory nodes to proximity

ACPI: RISCV: Add NUMA support based on SRAT and SLIT

Add acpi_numa.c file to enable parse NUMA information from
ACPI SRAT and SLIT tables. SRAT table provide CPUs(Hart) and
memory nodes to proximity domain mapping, while SLIT table
provide the distance metrics between proximity domains.

Signed-off-by: Haibo Xu <[email protected]>
Reviewed-by: Sunil V L <[email protected]>
Reviewed-by: Hanjun Guo <[email protected]>
Link: https://lore.kernel.org/r/65dbad1fda08a32922c44886e4581e49b4a2fecc.1718268003.git.haibo1.xu@intel.com
Signed-off-by: Palmer Dabbelt <[email protected]>

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riscv: Remove unused members from struct cpu_operations

name is not used anywhere at all. cpu_prepare and cpu_disable do nothing
and always return 0 if implemented.

Signed-off-by: Samuel Holland <s

riscv: Remove unused members from struct cpu_operations

name is not used anywhere at all. cpu_prepare and cpu_disable do nothing
and always return 0 if implemented.

Signed-off-by: Samuel Holland <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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riscv: convert to use arch_cpu_is_hotpluggable()

Convert riscv to use the arch_cpu_is_hotpluggable() helper rather than
arch_register_cpu().

Acked-by: Palmer Dabbelt <[email protected]>
Reviewed-

riscv: convert to use arch_cpu_is_hotpluggable()

Convert riscv to use the arch_cpu_is_hotpluggable() helper rather than
arch_register_cpu().

Acked-by: Palmer Dabbelt <[email protected]>
Reviewed-by: Gavin Shan <[email protected]>
Signed-off-by: "Russell King (Oracle)" <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
Reviewed-by: Samuel Holland <[email protected]>
Tested-by: Samuel Holland <[email protected]> # On HiFive Unmatched
Reviewed-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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riscv: Switch over to GENERIC_CPU_DEVICES

Now that GENERIC_CPU_DEVICES calls arch_register_cpu(), which can be
overridden by the arch code, switch over to this to allow common code
to choose when th

riscv: Switch over to GENERIC_CPU_DEVICES

Now that GENERIC_CPU_DEVICES calls arch_register_cpu(), which can be
overridden by the arch code, switch over to this to allow common code
to choose when the register_cpu() call is made.

This allows topology_init() to be removed.

This is an intermediate step to the logic being moved to drivers/acpi,
where GENERIC_CPU_DEVICES will do the work when booting with acpi=off.

This patch also has the effect of moving the registration of CPUs from
subsys to driver core initialisation, prior to any initcalls running.

Signed-off-by: James Morse <[email protected]>
Reviewed-by: Jonathan Cameron <[email protected]>
Acked-by: Palmer Dabbelt <[email protected]>
Reviewed-by: Gavin Shan <[email protected]>
Signed-off-by: "Russell King (Oracle)" <[email protected]>
Reviewed-by: Samuel Holland <[email protected]>
Tested-by: Samuel Holland <[email protected]>
Reviewed-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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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 bo

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 <[email protected]>
Reviewed-by: Javier Martinez Canillas <[email protected]>
Acked-by: Helge Deller <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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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 vga16

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 <[email protected]>
Reviewed-by: Thomas Zimmermann <[email protected]>
Reviewed-by: Khalid Aziz <[email protected]>
Acked-by: Helge Deller <[email protected]>
Signed-off-by: Arnd Bergmann <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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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

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 <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: [email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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riscv: kdump: use generic interface to simplify crashkernel reservation

With the help of newly changed function parse_crashkernel() and generic
reserve_crashkernel_generic(), crashkernel reservation

riscv: kdump: use generic interface to simplify crashkernel reservation

With the help of newly changed function parse_crashkernel() and generic
reserve_crashkernel_generic(), crashkernel reservation can be simplified
by steps:

1) Add a new header file <asm/crash_core.h>, and define CRASH_ALIGN,
CRASH_ADDR_LOW_MAX, CRASH_ADDR_HIGH_MAX and
DEFAULT_CRASH_KERNEL_LOW_SIZE in <asm/crash_core.h>;

2) Add arch_reserve_crashkernel() to call parse_crashkernel() and
reserve_crashkernel_generic();

3) Add ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION Kconfig in
arch/riscv/Kconfig.

The old reserve_crashkernel_low() and reserve_crashkernel() can be
removed.

[[email protected]: fix crashkernel reserving problem on RISC-V]
Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Baoquan He <[email protected]>
Signed-off-by: Chen Jiahao <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Chen Jiahao <[email protected]>
Cc: Zhen Lei <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

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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, whic

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 <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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 <[email protected]>
Signed-off-by: Alexandre Ghi

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 <[email protected]>
Signed-off-by: Alexandre Ghiti <[email protected]>
Tested-by: Conor Dooley <[email protected]>
Tested-by: Song Shuai <[email protected]>
Reviewed-by: Sami Tolvanen <[email protected]>
Tested-by: Sami Tolvanen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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
Im

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/[email protected]/ [1]

Signed-off-by: Jisheng Zhang <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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 alloca

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 <[email protected]>
Acked-by: Guo Ren <[email protected]>
Acked-by: Baoquan He <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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
he

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 <[email protected]>
Signed-off-by: Vincent Chen <[email protected]>
Signed-off-by: Greentime Hu <[email protected]>
Suggested-by: Vineet Gupta <[email protected]>
Suggested-by: Richard Henderson <[email protected]>
Co-developed-by: Andy Chiu <[email protected]>
Signed-off-by: Andy Chiu <[email protected]>
Acked-by: Conor Dooley <[email protected]>
Acked-by: Heiko Stuebner <[email protected]>
Tested-by: Heiko Stuebner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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, inste

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 <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Reviewed-by: Andrew Jones <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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 th

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 <[email protected]>
Acked-by: Rafael J. Wysocki <[email protected]>
Reviewed-by: Andrew Jones <[email protected]>
Acked-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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 enab

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 <[email protected]>
Reviewed-by: Anup Patel <[email protected]>
Reviewed-by: Atish Patra <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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 fix

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 <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: [email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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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

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: 922b0375fc93 ("riscv: Fix memblock reservation for device tree blob")
Fixes: 8f3a2b4a96dc ("RISC-V: Move DT mapping outof fixmap")
Fixes: 50e63dd8ed92 ("riscv: fix reserved memory setup")
Reported-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: Alexandre Ghiti <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Tested-by: Conor Dooley <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: [email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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