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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of/fdt: Restore possibility to use both ACPI and FDT from bootloader

There are cases when the bootloader provides information to the kernel
in both ACPI and DTB, not interchangeably. One such use ca

of/fdt: Restore possibility to use both ACPI and FDT from bootloader

There are cases when the bootloader provides information to the kernel
in both ACPI and DTB, not interchangeably. One such use case is virtual
machines in Android. When running on x86, the Android Virtualization
Framework (AVF) boots VMs with ACPI like it is usually done on x86 (i.e.
the virtual LAPIC, IOAPIC, HPET, PCI MMCONFIG etc are described in ACPI)
but also passes various AVF-specific boot parameters in DTB. This allows
reusing the same implementations of various AVF components on both
arm64 and x86.

Commit 7b937cc243e5 ("of: Create of_root if no dtb provided by firmware")
removed the possibility to do that, since among other things
it introduced forcing emptying the bootloader-provided DTB if ACPI is
enabled (probably assuming that if ACPI is available, a DTB can only be
useful for applying overlays to it afterwards, for testing purposes).

So restore this possibility. Instead of completely preventing using ACPI
and DT together, rely on arch-specific setup code to prevent using both
to set up the same things (see various acpi_disabled checks under arch/).

Fixes: 7b937cc243e5 ("of: Create of_root if no dtb provided by firmware")
Signed-off-by: Dmytro Maluka <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[email protected]>

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of/fdt: Check fdt_get_mem_rsv() error in early_init_fdt_scan_reserved_mem()

early_init_fdt_scan_reserved_mem() invoks fdt_get_mem_rsv(), and it will
use uninitialized variables @base and @size once

of/fdt: Check fdt_get_mem_rsv() error in early_init_fdt_scan_reserved_mem()

early_init_fdt_scan_reserved_mem() invoks fdt_get_mem_rsv(), and it will
use uninitialized variables @base and @size once the callee suffers error.

Fix by checking fdt_get_mem_rsv() error as other callers do.

Signed-off-by: Zijun Hu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[email protected]>

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of/fdt: Implement use BIN_ATTR_SIMPLE macro for fdt sysfs attribute

The usage of the macro allows to remove the custom handler function,
saving some memory. Additionally the code is easier to read.

of/fdt: Implement use BIN_ATTR_SIMPLE macro for fdt sysfs attribute

The usage of the macro allows to remove the custom handler function,
saving some memory. Additionally the code is easier to read.

While at it also mark the attribute as __ro_after_init, as the only
modification happens in the __init phase.

Signed-off-by: Thomas Weißschuh <[email protected]>
Link: https://lore.kernel.org/r/20241122-sysfs-const-bin_attr-of-v1-1-7052f9dcd4be@weissschuh.net
Signed-off-by: Rob Herring (Arm) <[email protected]>

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of: WARN on deprecated #address-cells/#size-cells handling

While OpenFirmware originally allowed walking parent nodes and default
root values for #address-cells and #size-cells, FDT has long require

of: WARN on deprecated #address-cells/#size-cells handling

While OpenFirmware originally allowed walking parent nodes and default
root values for #address-cells and #size-cells, FDT has long required
explicit values. It's been a warning in dtc for the root node since the
beginning (2005) and for any parent node since 2007. Of course, not all
FDT uses dtc, but that should be the majority by far. The various
extracted OF devicetrees I have dating back to the 1990s (various
PowerMac, OLPC, PASemi Nemo) all have explicit root node properties. The
warning is disabled for Sparc as there are known systems relying on
default root node values.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[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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of: reserved_mem: Restructure how the reserved memory regions are processed

Reserved memory regions defined in the devicetree can be broken up into
two groups:
i) Statically-placed reserved memory r

of: reserved_mem: Restructure how the reserved memory regions are processed

Reserved memory regions defined in the devicetree can be broken up into
two groups:
i) Statically-placed reserved memory regions
i.e. regions defined with a static start address and size using the
"reg" property.
ii) Dynamically-placed reserved memory regions.
i.e. regions defined by specifying an address range where they can be
placed in memory using the "alloc_ranges" and "size" properties.

These regions are processed and set aside at boot time.
This is done in two stages as seen below:

Stage 1:
At this stage, fdt_scan_reserved_mem() scans through the child nodes of
the reserved_memory node using the flattened devicetree and does the
following:

1) If the node represents a statically-placed reserved memory region,
i.e. if it is defined using the "reg" property:
- Call memblock_reserve() or memblock_mark_nomap() as needed.
- Add the information for that region into the reserved_mem array
using fdt_reserved_mem_save_node().
i.e. fdt_reserved_mem_save_node(node, name, base, size).

2) If the node represents a dynamically-placed reserved memory region,
i.e. if it is defined using "alloc-ranges" and "size" properties:
- Add the information for that region to the reserved_mem array with
the starting address and size set to 0.
i.e. fdt_reserved_mem_save_node(node, name, 0, 0).
Note: This region is saved to the array with a starting address of 0
because a starting address is not yet allocated for it.

Stage 2:
After iterating through all the reserved memory nodes and storing their
relevant information in the reserved_mem array,fdt_init_reserved_mem() is
called and does the following:

1) For statically-placed reserved memory regions:
- Call the region specific init function using
__reserved_mem_init_node().
2) For dynamically-placed reserved memory regions:
- Call __reserved_mem_alloc_size() which is used to allocate memory
for each of these regions, and mark them as nomap if they have the
nomap property specified in the DT.
- Call the region specific init function.

The current size of the resvered_mem array is 64 as is defined by
MAX_RESERVED_REGIONS. This means that there is a limitation of 64 for
how many reserved memory regions can be specified on a system.
As systems continue to grow more and more complex, the number of
reserved memory regions needed are also growing and are starting to hit
this 64 count limit, hence the need to make the reserved_mem array
dynamically sized (i.e. dynamically allocating memory for the
reserved_mem array using membock_alloc_*).

On architectures such as arm64, memory allocated using memblock is
writable only after the page tables have been setup. This means that if
the reserved_mem array is going to be dynamically allocated, it needs to
happen after the page tables have been setup, not before.

Since the reserved memory regions are currently being processed and
added to the array before the page tables are setup, there is a need to
change the order in which some of the processing is done to allow for
the reserved_mem array to be dynamically sized.

It is possible to process the statically-placed reserved memory regions
without needing to store them in the reserved_mem array until after the
page tables have been setup because all the information stored in the
array is readily available in the devicetree and can be referenced at
any time.
Dynamically-placed reserved memory regions on the other hand get
assigned a start address only at runtime, and hence need a place to be
stored once they are allocated since there is no other referrence to the
start address for these regions.

Hence this patch changes the processing order of the reserved memory
regions in the following ways:

Step 1:
fdt_scan_reserved_mem() scans through the child nodes of
the reserved_memory node using the flattened devicetree and does the
following:

1) If the node represents a statically-placed reserved memory region,
i.e. if it is defined using the "reg" property:
- Call memblock_reserve() or memblock_mark_nomap() as needed.

2) If the node represents a dynamically-placed reserved memory region,
i.e. if it is defined using "alloc-ranges" and "size" properties:
- Call __reserved_mem_alloc_size() which will:
i) Allocate memory for the reserved region and call
memblock_mark_nomap() as needed.
ii) Call the region specific initialization function using
fdt_init_reserved_mem_node().
iii) Save the region information in the reserved_mem array using
fdt_reserved_mem_save_node().

Step 2:
1) This stage of the reserved memory processing is now only used to add
the statically-placed reserved memory regions into the reserved_mem
array using fdt_scan_reserved_mem_reg_nodes(), as well as call their
region specific initialization functions.

2) This step has also been moved to be after the page tables are
setup. Moving this will allow us to replace the reserved_mem
array with a dynamically sized array before storing the rest of
these regions.

Signed-off-by: Oreoluwa Babatunde <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring (Arm) <[email protected]>

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kbuild: split device tree build rules into scripts/Makefile.dtbs

scripts/Makefile.lib is included not only from scripts/Makefile.build
but also from scripts/Makefile.{modfinal,package,vmlinux,vmlinu

kbuild: split device tree build rules into scripts/Makefile.dtbs

scripts/Makefile.lib is included not only from scripts/Makefile.build
but also from scripts/Makefile.{modfinal,package,vmlinux,vmlinux_o},
where DT build rules are not required.

Split the DT build rules out to scripts/Makefile.dtbs, and include it
only when necessary.

While I was here, I added $(DT_TMP_SCHEMA) as a prerequisite of
$(multi-dtb-y).

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Rob Herring (Arm) <[email protected]>

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of/fdt: avoid re-parsing '#{address,size}-cells' in of_fdt_limit_memory

Now that we initialize dt_root_addr_cells and dt_root_size_cells earlier,
use them and simplify of_fdt_limit_memory.

Link: ht

of/fdt: avoid re-parsing '#{address,size}-cells' in of_fdt_limit_memory

Now that we initialize dt_root_addr_cells and dt_root_size_cells earlier,
use them and simplify of_fdt_limit_memory.

Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: Rob Herring <[email protected]>

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of/fdt: Scan the root node properties earlier

Scan the root node properties (#{size,address}-cells) earlier, so that
the dt_root_addr_cells and dt_root_size_cells variables are initialized
and can b

of/fdt: Scan the root node properties earlier

Scan the root node properties (#{size,address}-cells) earlier, so that
the dt_root_addr_cells and dt_root_size_cells variables are initialized
and can be used.

Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: Rob Herring <[email protected]>

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of: Move all FDT reserved-memory handling into of_reserved_mem.c

The split of /reserved-memory handling between fdt.c and
of_reserved_mem.c makes for reading and restructuring the code
difficult. As

of: Move all FDT reserved-memory handling into of_reserved_mem.c

The split of /reserved-memory handling between fdt.c and
of_reserved_mem.c makes for reading and restructuring the code
difficult. As of_reserved_mem.c is only built for
CONFIG_OF_EARLY_FLATTREE already, move all the code to one spot.

Acked-by: Saravana Kannan <[email protected]>
Reviewed-by: Oreoluwa Babatunde <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of: Create of_root if no dtb provided by firmware

When enabling CONFIG_OF on a platform where 'of_root' is not populated
by firmware, we end up without a root node. In order to apply overlays
and cr

of: Create of_root if no dtb provided by firmware

When enabling CONFIG_OF on a platform where 'of_root' is not populated
by firmware, we end up without a root node. In order to apply overlays
and create subnodes of the root node, we need one. Create this root node
by unflattening an empty builtin dtb.

If firmware provides a flattened device tree (FDT) then the FDT is
unflattened via setup_arch(). Otherwise, the call to
unflatten(_and_copy)?_device_tree() will create an empty root node.

We make of_have_populated_dt() return true only if the DTB was loaded by
firmware so that existing callers don't change behavior after this
patch. The call in the of platform code is removed because it prevents
overlays from creating platform devices when the empty root node is
used.

[[email protected]: Update of_have_populated_dt() to treat this empty dtb
as not populated. Drop setup_of() initcall]

Signed-off-by: Frank Rowand <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Cc: Rob Herring <[email protected]>
Signed-off-by: Stephen Boyd <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of: Always unflatten in unflatten_and_copy_device_tree()

We want to populate an empty DT whenever CONFIG_OF is enabled so that
overlays can be applied and the DT unit tests can be run. Make
unflatte

of: Always unflatten in unflatten_and_copy_device_tree()

We want to populate an empty DT whenever CONFIG_OF is enabled so that
overlays can be applied and the DT unit tests can be run. Make
unflatten_and_copy_device_tree() stop printing a warning if the
'initial_boot_params' pointer is NULL. Instead, simply copy the dtb if
there is one and then unflatten it. If there isn't a DT to copy, then
the call to unflatten_device_tree() is largely a no-op, so nothing
really changes here.

Cc: Rob Herring <[email protected]>
Cc: Frank Rowand <[email protected]>
Signed-off-by: Stephen Boyd <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of: fdt: Scan /memreserve/ last

Change the scanning /memreserve/ and /reserved-memory node order to fix
Kernel panic on Khadas Vim3 Board.

If /memreserve/ goes first, the memory is reserved, but no

of: fdt: Scan /memreserve/ last

Change the scanning /memreserve/ and /reserved-memory node order to fix
Kernel panic on Khadas Vim3 Board.

If /memreserve/ goes first, the memory is reserved, but nomap can't be
applied to the region. So the memory won't be used by Linux, but it is
still present in the linear map as normal memory, which allows
speculation. Legitimate access to adjacent pages will cause the CPU
to end up prefetching into them leading to Kernel panic.

So /reserved-memory node should go first, as it has a more updated
description of the memory regions and can apply flags, like nomap.

Link: https://lore.kernel.org/all/CAJX_Q+1Tjc+-TjZ6JW9X0NxEdFe=82a9626yL63j7uVD4LpxEA@mail.gmail.com/
Signed-off-by: Lucas Tanure <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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riscv: Use PUD/P4D/PGD pages for the linear mapping

During the early page table creation, we used to set the mapping for
PAGE_OFFSET to the kernel load address: but the kernel load address is
always

riscv: Use PUD/P4D/PGD pages for the linear mapping

During the early page table creation, we used to set the mapping for
PAGE_OFFSET to the kernel load address: but the kernel load address is
always offseted by PMD_SIZE which makes it impossible to use PUD/P4D/PGD
pages as this physical address is not aligned on PUD/P4D/PGD size (whereas
PAGE_OFFSET is).

But actually we don't have to establish this mapping (ie set va_pa_offset)
that early in the boot process because:

- first, setup_vm installs a temporary kernel mapping and among other
things, discovers the system memory,
- then, setup_vm_final creates the final kernel mapping and takes
advantage of the discovered system memory to create the linear
mapping.

During the first phase, we don't know the start of the system memory and
then until the second phase is finished, we can't use the linear mapping at
all and phys_to_virt/virt_to_phys translations must not be used because it
would result in a different translation from the 'real' one once the final
mapping is installed.

So here we simply delay the initialization of va_pa_offset to after the
system memory discovery. But to make sure noone uses the linear mapping
before, we add some guard in the DEBUG_VIRTUAL config.

Finally we can use PUD/P4D/PGD hugepages when possible, which will result
in a better TLB utilization.

Note that:
- this does not apply to rv32 as the kernel mapping lies in the linear
mapping.
- we rely on the firmware to protect itself using PMP.

Signed-off-by: Alexandre Ghiti <[email protected]>
Acked-by: Rob Herring <[email protected]> # DT bits
Reviewed-by: Andrew Jones <[email protected]>
Reviewed-by: Anup Patel <[email protected]>
Tested-by: Anup Patel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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Revert "mm: kmemleak: alloc gray object for reserved region with direct map"

This reverts commit 972fa3a7c17c9d60212e32ecc0205dc585b1e769.

Kmemleak operates by periodically scanning memory regions

Revert "mm: kmemleak: alloc gray object for reserved region with direct map"

This reverts commit 972fa3a7c17c9d60212e32ecc0205dc585b1e769.

Kmemleak operates by periodically scanning memory regions for pointers to
allocated memory blocks to determine if they are leaked or not. However,
reserved memory regions can be used for DMA transactions between a device
and a CPU, and thus, wouldn't contain pointers to allocated memory blocks,
making them inappropriate for kmemleak to scan. Thus, revert this commit.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 972fa3a7c17c9 ("mm: kmemleak: alloc gray object for reserved region with direct map")
Signed-off-by: Isaac J. Manjarres <[email protected]>
Acked-by: Catalin Marinas <[email protected]>
Cc: Calvin Zhang <[email protected]>
Cc: Frank Rowand <[email protected]>
Cc: Rob Herring <[email protected]>
Cc: Saravana Kannan <[email protected]>
Cc: <[email protected]> [5.17+]
Signed-off-by: Andrew Morton <[email protected]>

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of: fdt: Honor CONFIG_CMDLINE* even without /chosen node, take 2

I do not read a strict requirement on /chosen node in either ePAPR or in
Documentation/devicetree. Help text for CONFIG_CMDLINE and
C

of: fdt: Honor CONFIG_CMDLINE* even without /chosen node, take 2

I do not read a strict requirement on /chosen node in either ePAPR or in
Documentation/devicetree. Help text for CONFIG_CMDLINE and
CONFIG_CMDLINE_EXTEND doesn't make their behavior explicitly dependent on
the presence of /chosen or the presense of /chosen/bootargs.

However the early check for /chosen and bailing out in
early_init_dt_scan_chosen() skips CONFIG_CMDLINE handling which is not
really related to /chosen node or the particular method of passing cmdline
from bootloader.

This leads to counterintuitive combinations (assuming
CONFIG_CMDLINE_EXTEND=y):

a) bootargs="foo", CONFIG_CMDLINE="bar" => cmdline=="foo bar"
b) /chosen missing, CONFIG_CMDLINE="bar" => cmdline==""
c) bootargs="", CONFIG_CMDLINE="bar" => cmdline==" bar"

Rework early_init_dt_scan_chosen() so that the cmdline config options are
always handled.

[commit msg written by Alexander Sverdlin]

Cc: Alexander Sverdlin <[email protected]>
Cc: Linus Walleij <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Tested-by: Geoff Levand <[email protected]>
Reviewed-by: Alexander Sverdlin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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Revert "of: fdt: Honor CONFIG_CMDLINE* even without /chosen node"

This reverts commit a7d550f82b445cf218b47a2c1a9c56e97ecb8c7a.

Some arches (PPC at least) don't call early_init_dt_scan_nodes(), so

Revert "of: fdt: Honor CONFIG_CMDLINE* even without /chosen node"

This reverts commit a7d550f82b445cf218b47a2c1a9c56e97ecb8c7a.

Some arches (PPC at least) don't call early_init_dt_scan_nodes(), so
moving the cmdline processing there breaks them.

Reported-by: Geoff Levand <[email protected]>
Cc: Alexander Sverdlin <[email protected]>
Tested-by: Geoff Levand <[email protected]>
Reviewed-by: Alexander Sverdlin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of/fdt: run soc memory setup when early_init_dt_scan_memory fails

If memory has been found early_init_dt_scan_memory now returns 1. If
it hasn't found any memory it will return 0, allowing other mem

of/fdt: run soc memory setup when early_init_dt_scan_memory fails

If memory has been found early_init_dt_scan_memory now returns 1. If
it hasn't found any memory it will return 0, allowing other memory
setup mechanisms to carry on.

Previously early_init_dt_scan_memory always returned 0 without
distinguishing between any kind of memory setup being done or not. Any
code path after the early_init_dt_scan memory call in the ramips
plat_mem_setup code wouldn't be executed anymore. Making
early_init_dt_scan_memory the only way to initialize the memory.

Some boards, including my mt7621 based Cudy X6 board, depend on memory
initialization being done via the soc_info.mem_detect function
pointer. Those wouldn't be able to obtain memory and panic the kernel
during early bootup with the message "early_init_dt_alloc_memory_arch:
Failed to allocate 12416 bytes align=0x40".

Fixes: 1f012283e936 ("of/fdt: Rework early_init_dt_scan_memory() to call directly")
Cc: [email protected]
Signed-off-by: Andreas Rammhold <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of: fdt: Honor CONFIG_CMDLINE* even without /chosen node

I do not read a strict requirement on /chosen node in either ePAPR or in
Documentation/devicetree. Help text for CONFIG_CMDLINE and
CONFIG_CM

of: fdt: Honor CONFIG_CMDLINE* even without /chosen node

I do not read a strict requirement on /chosen node in either ePAPR or in
Documentation/devicetree. Help text for CONFIG_CMDLINE and
CONFIG_CMDLINE_EXTEND doesn't make their behavior explicitly dependent on
the presence of /chosen or the presense of /chosen/bootargs.

However the early check for /chosen and bailing out in
early_init_dt_scan_chosen() skips CONFIG_CMDLINE handling which is not
really related to /chosen node or the particular method of passing cmdline
from bootloader.

This leads to counterintuitive combinations (assuming
CONFIG_CMDLINE_EXTEND=y):

a) bootargs="foo", CONFIG_CMDLINE="bar" => cmdline=="foo bar"
b) /chosen missing, CONFIG_CMDLINE="bar" => cmdline==""
c) bootargs="", CONFIG_CMDLINE="bar" => cmdline==" bar"

Move CONFIG_CMDLINE handling outside of early_init_dt_scan_chosen() so that
cases b and c above result in the same cmdline.

Signed-off-by: Alexander Sverdlin <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of: fdt: Remove unused struct fdt_scan_status

After commit bba04d965d06("of/fdt: remove unused of_scan_flat_dt_by_path"), no
one use struct fdt_scan_status, so remove it.

Signed-off-by: Yuan Can <y

of: fdt: Remove unused struct fdt_scan_status

After commit bba04d965d06("of/fdt: remove unused of_scan_flat_dt_by_path"), no
one use struct fdt_scan_status, so remove it.

Signed-off-by: Yuan Can <[email protected]>
Reviewed-by: Frank Rowand <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of/fdt: Don't calculate initrd size from DT if start > end

If the properties 'linux,initrd-start' and 'linux,initrd-end' of
the chosen node populated from the bootloader, eg. U-Boot, are so that
sta

of/fdt: Don't calculate initrd size from DT if start > end

If the properties 'linux,initrd-start' and 'linux,initrd-end' of
the chosen node populated from the bootloader, eg. U-Boot, are so that
start > end, then the phys_initrd_size calculated from end - start is
negative that subsequently gets converted to a high positive value for
being unsigned long long. Then, the memory region with the (invalid)
size is added to the bootmem and attempted being paged in paging_init()
that results in the kernel fault.

For example, on the FVP ARM64 system I'm running, the U-Boot populates
the 'linux,initrd-start' with 8800_0000 and 'linux,initrd-end' with 0.
The phys_initrd_size calculated is then ffff_ffff_7800_0000
(= 0 - 8800_0000 = -8800_0000 + ULLONG_MAX + 1). paging_init() then
attempts to map the address 8800_0000 + ffff_ffff_7800_0000 and oops'es
as below.

It should be stressed, it is generally a fault of the bootloader's with
the kernel relying on it, however we should not allow the bootloader's
misconfiguration to lead to the kernel oops. Not only the kernel should be
bullet proof against it but also finding the root cause of the paging
fault spanning over the bootloader, DT, and kernel may happen is not so
easy.

Unable to handle kernel paging request at virtual address fffffffefe43c000
Mem abort info:
ESR = 0x96000007
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000007
CM = 0, WnR = 0
swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000080e3d000
[fffffffefe43c000] pgd=0000000080de9003, pud=0000000080de9003
Unable to handle kernel paging request at virtual address ffffff8000de9f90
Mem abort info:
ESR = 0x96000005
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
Data abort info:
ISV = 0, ISS = 0x00000005
CM = 0, WnR = 0
swapper pgtable: 4k pages, 39-bit VAs, pgdp=0000000080e3d000
[ffffff8000de9f90] pgd=0000000000000000, pud=0000000000000000
Internal error: Oops: 96000005 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.4.51-yocto-standard #1
Hardware name: FVP Base (DT)
pstate: 60000085 (nZCv daIf -PAN -UAO)
pc : show_pte+0x12c/0x1b4
lr : show_pte+0x100/0x1b4
sp : ffffffc010ce3b30
x29: ffffffc010ce3b30 x28: ffffffc010ceed80
x27: fffffffefe43c000 x26: fffffffefe43a028
x25: 0000000080bf0000 x24: 0000000000000025
x23: ffffffc010b8d000 x22: ffffffc010e3d000
x23: ffffffc010b8d000 x22: ffffffc010e3d000
x21: 0000000080de9000 x20: ffffff7f80000f90
x19: fffffffefe43c000 x18: 0000000000000030
x17: 0000000000001400 x16: 0000000000001c00
x15: ffffffc010cef1b8 x14: ffffffffffffffff
x13: ffffffc010df1f40 x12: ffffffc010df1b70
x11: ffffffc010ce3b30 x10: ffffffc010ce3b30
x9 : 00000000ffffffc8 x8 : 0000000000000000
x7 : 000000000000000f x6 : ffffffc010df16e8
x5 : 0000000000000000 x4 : 0000000000000000
x3 : 00000000ffffffff x2 : 0000000000000000
x1 : 0000008080000000 x0 : ffffffc010af1d68
Call trace:
show_pte+0x12c/0x1b4
die_kernel_fault+0x54/0x78
__do_kernel_fault+0x11c/0x128
do_translation_fault+0x58/0xac
do_mem_abort+0x50/0xb0
el1_da+0x1c/0x90
__create_pgd_mapping+0x348/0x598
paging_init+0x3f0/0x70d0
setup_arch+0x2c0/0x5d4
start_kernel+0x94/0x49c
Code: 92748eb5 900052a0 9135a000 cb010294 (f8756a96) 

Signed-off-by: Marek Bykowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Rob Herring <[email protected]>

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of: move from strlcpy with unused retval to strscpy

Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a

of: move from strlcpy with unused retval to strscpy

Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <[email protected]>
Signed-off-by: Rob Herring <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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of: fdt: fix off-by-one error in unflatten_dt_nodes()

Commit 78c44d910d3e ("drivers/of: Fix depth when unflattening devicetree")
forgot to fix up the depth check in the loop body in unflatten_dt_nod

of: fdt: fix off-by-one error in unflatten_dt_nodes()

Commit 78c44d910d3e ("drivers/of: Fix depth when unflattening devicetree")
forgot to fix up the depth check in the loop body in unflatten_dt_nodes()
which makes it possible to overflow the nps[] buffer...

Found by Linux Verification Center (linuxtesting.org) with the SVACE static
analysis tool.

Fixes: 78c44d910d3e ("drivers/of: Fix depth when unflattening devicetree")
Signed-off-by: Sergey Shtylyov <[email protected]>
Signed-off-by: Rob Herring <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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of/fdt: declared return type does not match actual return type

The commit 649cab56de8e (“of: properly check for error returned
by fdt_get_name()”) changed the return value type from bool to int,
but

of/fdt: declared return type does not match actual return type

The commit 649cab56de8e (“of: properly check for error returned
by fdt_get_name()”) changed the return value type from bool to int,
but forgot to change the return value simultaneously.

populate_node was only called in unflatten_dt_nodes, and returns
with values greater than or equal to 0 were discarded without further
processing. Considering that return 0 usually indicates success,
return 0 instead of return true.

Fixes: 649cab56de8e (“of: properly check for error returned by fdt_get_name()”)
Signed-off-by: Xu Qiang <[email protected]>
Signed-off-by: Rob Herring <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

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