bootconfig: Remove duplicate included header file linux/bootconfig.h

The header file linux/bootconfig.h is included whether __KERNEL__ is
defined or not.

Include it only once before the #ifdef/#els

bootconfig: Remove duplicate included header file linux/bootconfig.h

The header file linux/bootconfig.h is included whether __KERNEL__ is
defined or not.

Include it only once before the #ifdef/#else/#endif preprocessor
directives and remove the following make includecheck warning:

linux/bootconfig.h is included more than once

Move the comment to the top and delete the now empty #else block.

Link: https://lore.kernel.org/all/[email protected]/

Signed-off-by: Thorsten Blum <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>

show more ...

bootconfig: Fix the kerneldoc of _xbc_exit()

Fix the kerneldoc of _xbc_exit() which is updated to have an @early
argument and the function name is changed.

Link: https://lore.kernel.org/all/1713217

bootconfig: Fix the kerneldoc of _xbc_exit()

Fix the kerneldoc of _xbc_exit() which is updated to have an @early
argument and the function name is changed.

Link: https://lore.kernel.org/all/171321744474.599864.13532445969528690358.stgit@devnote2/

Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Fixes: 89f9a1e876b5 ("bootconfig: use memblock_free_late to free xbc memory to buddy")
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>

show more ...

bootconfig: use memblock_free_late to free xbc memory to buddy

On the time to free xbc memory in xbc_exit(), memblock may has handed
over memory to buddy allocator. So it doesn't make sense to free

bootconfig: use memblock_free_late to free xbc memory to buddy

On the time to free xbc memory in xbc_exit(), memblock may has handed
over memory to buddy allocator. So it doesn't make sense to free memory
back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs
on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86.
Following KASAN logs shows this case.

This patch fixes the xbc memory free problem by calling memblock_free()
in early xbc init error rewind path and calling memblock_free_late() in
xbc exit path to free memory to buddy allocator.

[ 9.410890] ==================================================================
[ 9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260
[ 9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1

[ 9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G U 6.9.0-rc3-00208-g586b5dfb51b9 #5
[ 9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023
[ 9.460789] Call Trace:
[ 9.463518] <TASK>
[ 9.465859] dump_stack_lvl+0x53/0x70
[ 9.469949] print_report+0xce/0x610
[ 9.473944] ? __virt_addr_valid+0xf5/0x1b0
[ 9.478619] ? memblock_isolate_range+0x12d/0x260
[ 9.483877] kasan_report+0xc6/0x100
[ 9.487870] ? memblock_isolate_range+0x12d/0x260
[ 9.493125] memblock_isolate_range+0x12d/0x260
[ 9.498187] memblock_phys_free+0xb4/0x160
[ 9.502762] ? __pfx_memblock_phys_free+0x10/0x10
[ 9.508021] ? mutex_unlock+0x7e/0xd0
[ 9.512111] ? __pfx_mutex_unlock+0x10/0x10
[ 9.516786] ? kernel_init_freeable+0x2d4/0x430
[ 9.521850] ? __pfx_kernel_init+0x10/0x10
[ 9.526426] xbc_exit+0x17/0x70
[ 9.529935] kernel_init+0x38/0x1e0
[ 9.533829] ? _raw_spin_unlock_irq+0xd/0x30
[ 9.538601] ret_from_fork+0x2c/0x50
[ 9.542596] ? __pfx_kernel_init+0x10/0x10
[ 9.547170] ret_from_fork_asm+0x1a/0x30
[ 9.551552] </TASK>

[ 9.555649] The buggy address belongs to the physical page:
[ 9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30
[ 9.570821] flags: 0x200000000000000(node=0|zone=2)
[ 9.576271] page_type: 0xffffffff()
[ 9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000
[ 9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
[ 9.597476] page dumped because: kasan: bad access detected

[ 9.605362] Memory state around the buggy address:
[ 9.610714] ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 9.618786] ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 9.634930] ^
[ 9.638534] ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 9.646605] ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[ 9.654675] ==================================================================

Link: https://lore.kernel.org/all/[email protected]/

Fixes: 40caa127f3c7 ("init: bootconfig: Remove all bootconfig data when the init memory is removed")
Cc: [email protected]
Signed-off-by: Qiang Zhang <[email protected]>
Acked-by: Masami Hiramatsu (Google) <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>

show more ...

bootconfig: Support embedding a bootconfig file in kernel

This allows kernel developer to embed a default bootconfig file in
the kernel instead of embedding it in the initrd. This will be good
for w

bootconfig: Support embedding a bootconfig file in kernel

This allows kernel developer to embed a default bootconfig file in
the kernel instead of embedding it in the initrd. This will be good
for who are using the kernel without initrd, or who needs a default
bootconfigs.
This needs to set two kconfigs: CONFIG_BOOT_CONFIG_EMBED=y and set
the file path to CONFIG_BOOT_CONFIG_EMBED_FILE.

Note that you still need 'bootconfig' command line option to load the
embedded bootconfig. Also if you boot using an initrd with a different
bootconfig, the kernel will use the bootconfig in the initrd, instead
of the default bootconfig.

Link: https://lkml.kernel.org/r/164921227943.1090670.14035119557571329218.stgit@devnote2

Cc: Padmanabha Srinivasaiah <[email protected]>
Cc: Jonathan Corbet <[email protected]>
Cc: Randy Dunlap <[email protected]>
Cc: Nick Desaulniers <[email protected]>
Cc: Sami Tolvanen <[email protected]>
Cc: Nathan Chancellor <[email protected]>
Cc: Masahiro Yamada <[email protected]>
Cc: Linux Kbuild mailing list <[email protected]>
Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>

show more ...

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
counte

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);
)

[[email protected]: fixup]
Link: https://lkml.kernel.org/r/[email protected]

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Mike Rapoport <[email protected]>
Signed-off-by: Stephen Rothwell <[email protected]>
Cc: Christophe Leroy <[email protected]>
Cc: Juergen Gross <[email protected]>
Cc: Shahab Vahedi <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

bootconfig: Initialize ret in xbc_parse_tree()

The do while loop continues while ret is zero, but ret is never
initialized. The check for ret in the loop at the while should always be
initialized, b

bootconfig: Initialize ret in xbc_parse_tree()

The do while loop continues while ret is zero, but ret is never
initialized. The check for ret in the loop at the while should always be
initialized, but if an empty string were to be passed in, q would be NULL
and p would be '\0', and it would break out of the loop without ever
setting ret.

Set ret to zero, and then xbc_verify_tree() would be called and catch that
it is an empty tree and report the proper error.

Link: https://lkml.kernel.org/r/[email protected]

Fixes: bdac5c2b243f ("bootconfig: Allocate xbc_data inside xbc_init()")
Reported-by: kernel test robot <[email protected]>
Reported-by: Andrew Morton <[email protected]>
Acked-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

lib/bootconfig: Fix the xbc_get_info kerneldoc

Fix the kernel doc of xbc_get_info() to add '@' to the parameters.

Link: https://lkml.kernel.org/r/163525086738.676803.15352231787913236933.stgit@devn

lib/bootconfig: Fix the xbc_get_info kerneldoc

Fix the kernel doc of xbc_get_info() to add '@' to the parameters.

Link: https://lkml.kernel.org/r/163525086738.676803.15352231787913236933.stgit@devnote2

Fixes: e306220cb7b7 ("bootconfig: Add xbc_get_info() for the node information")
Reported-by: Stephen Rothwell <[email protected]>
Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

lib/bootconfig: Make xbc_alloc_mem() and xbc_free_mem() as __init function

Since the xbc_alloc_mem() and xbc_free_mem() are used from
the __init functions and memblock_alloc() is __init function,
ma

lib/bootconfig: Make xbc_alloc_mem() and xbc_free_mem() as __init function

Since the xbc_alloc_mem() and xbc_free_mem() are used from
the __init functions and memblock_alloc() is __init function,
make them __init functions too.

Link: https://lkml.kernel.org/r/163515075747.547467.5746167540626712819.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Fixes: 4ee1b4cac236 ("bootconfig: Cleanup dummy headers in tools/bootconfig")
Reported-by: Stephen Rothwell <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Cleanup dummy headers in tools/bootconfig

Cleanup dummy headers in tools/bootconfig/include except
for tools/bootconfig/include/linux/bootconfig.h.
For this change, I use __KERNEL__ macr

bootconfig: Cleanup dummy headers in tools/bootconfig

Cleanup dummy headers in tools/bootconfig/include except
for tools/bootconfig/include/linux/bootconfig.h.
For this change, I use __KERNEL__ macro to split kernel
header #include and introduce xbc_alloc_mem() and
xbc_free_mem().

Link: https://lkml.kernel.org/r/163187299574.2366983.18371329724128746091.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Replace u16 and u32 with uint16_t and uint32_t

Replace u16 and u32 with uint16_t and uint32_t so
that the tools/bootconfig only needs <stdint.h>.

Link: https://lkml.kernel.org/r/1631872

bootconfig: Replace u16 and u32 with uint16_t and uint32_t

Replace u16 and u32 with uint16_t and uint32_t so
that the tools/bootconfig only needs <stdint.h>.

Link: https://lkml.kernel.org/r/163187298835.2366983.9838262576854319669.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Remove unused debug function

Remove unused xbc_debug_dump() from bootconfig for clean up
the code.

Link: https://lkml.kernel.org/r/163187297371.2366983.12943349701785875450.stgit@devnot

bootconfig: Remove unused debug function

Remove unused xbc_debug_dump() from bootconfig for clean up
the code.

Link: https://lkml.kernel.org/r/163187297371.2366983.12943349701785875450.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Split parse-tree part from xbc_init

Split bootconfig data parser to build tree code from
xbc_init(). This is an internal cosmetic change.

Link: https://lkml.kernel.org/r/163187296647.23

bootconfig: Split parse-tree part from xbc_init

Split bootconfig data parser to build tree code from
xbc_init(). This is an internal cosmetic change.

Link: https://lkml.kernel.org/r/163187296647.2366983.15590065167920474865.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Rename xbc_destroy_all() to xbc_exit()

Avoid using this noisy name and use more calm one.
This is just a name change. No functional change.

Link: https://lkml.kernel.org/r/163187295918.

bootconfig: Rename xbc_destroy_all() to xbc_exit()

Avoid using this noisy name and use more calm one.
This is just a name change. No functional change.

Link: https://lkml.kernel.org/r/163187295918.2366983.5231840238429996027.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Add xbc_get_info() for the node information

Add xbc_get_info() API which allows user to get the
number of used xbc_nodes and the size of bootconfig
data. This is also useful for checking

bootconfig: Add xbc_get_info() for the node information

Add xbc_get_info() API which allows user to get the
number of used xbc_nodes and the size of bootconfig
data. This is also useful for checking the bootconfig
is initialized or not.

Link: https://lkml.kernel.org/r/163177340877.682366.4360676589783197627.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Allocate xbc_data inside xbc_init()

Allocate 'xbc_data' in the xbc_init() so that it does
not need to care about the ownership of the copied
data.

Link: https://lkml.kernel.org/r/163177

bootconfig: Allocate xbc_data inside xbc_init()

Allocate 'xbc_data' in the xbc_init() so that it does
not need to care about the ownership of the copied
data.

Link: https://lkml.kernel.org/r/163177339986.682366.898762699429769117.stgit@devnote2

Suggested-by: Steven Rostedt <[email protected]>
Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

memblock: introduce saner 'memblock_free_ptr()' interface

The boot-time allocation interface for memblock is a mess, with
'memblock_alloc()' returning a virtual pointer, but then you are
supposed to

memblock: introduce saner 'memblock_free_ptr()' interface

The boot-time allocation interface for memblock is a mess, with
'memblock_alloc()' returning a virtual pointer, but then you are
supposed to free it with 'memblock_free()' that takes a _physical_
address.

Not only is that all kinds of strange and illogical, but it actually
causes bugs, when people then use it like a normal allocation function,
and it fails spectacularly on a NULL pointer:

https://lore.kernel.org/all/20210912140820.GD25450@xsang-OptiPlex-9020/

or just random memory corruption if the debug checks don't catch it:

https://lore.kernel.org/all/[email protected]/

I really don't want to apply patches that treat the symptoms, when the
fundamental cause is this horribly confusing interface.

I started out looking at just automating a sane replacement sequence,
but because of this mix or virtual and physical addresses, and because
people have used the "__pa()" macro that can take either a regular
kernel pointer, or just the raw "unsigned long" address, it's all quite
messy.

So this just introduces a new saner interface for freeing a virtual
address that was allocated using 'memblock_alloc()', and that was kept
as a regular kernel pointer. And then it converts a couple of users
that are obvious and easy to test, including the 'xbc_nodes' case in
lib/bootconfig.c that caused problems.

Reported-by: kernel test robot <[email protected]>
Fixes: 40caa127f3c7 ("init: bootconfig: Remove all bootconfig data when the init memory is removed")
Cc: Steven Rostedt <[email protected]>
Cc: Mike Rapoport <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Vlastimil Babka <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

bootconfig: Rename xbc_node_find_child() to xbc_node_find_subkey()

Rename xbc_node_find_child() to xbc_node_find_subkey() for
clarifying that function returns a key node (no value node).
Since there

bootconfig: Rename xbc_node_find_child() to xbc_node_find_subkey()

Rename xbc_node_find_child() to xbc_node_find_subkey() for
clarifying that function returns a key node (no value node).
Since there are xbc_node_for_each_child() (loop on all child
nodes) and xbc_node_for_each_subkey() (loop on only subkey
nodes), this name distinction is necessary to avoid confusing
users.

Link: https://lkml.kernel.org/r/163119459826.161018.11200274779483115300.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Support mixing a value and subkeys under a key

Support mixing a value and subkeys under a key. Since kernel cmdline
options will support "aaa.bbb=value1 aaa.bbb.ccc=value2", it is
better

bootconfig: Support mixing a value and subkeys under a key

Support mixing a value and subkeys under a key. Since kernel cmdline
options will support "aaa.bbb=value1 aaa.bbb.ccc=value2", it is
better that the bootconfig supports such configuration too.

Note that this does not change syntax itself but just accepts
mixed value and subkeys e.g.

key = value1
key.subkey = value2

But this is not accepted;

key {
value1
subkey = value2
}

That will make value1 as a subkey.

Also, the order of the value node under a key is fixed. If there
are a value and subkeys, the value is always the first child node
of the key. Thus if user specifies subkeys first, e.g.

key.subkey = value1
key = value2

In the program (and /proc/bootconfig), it will be shown as below

key = value2
key.subkey = value1

Link: https://lkml.kernel.org/r/162262194685.264090.7738574774030567419.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

bootconfig: Change array value to use child node

It is not possible to put an array value with subkeys under
a key node, because both of subkeys and the array elements
are using "next" field of the

bootconfig: Change array value to use child node

It is not possible to put an array value with subkeys under
a key node, because both of subkeys and the array elements
are using "next" field of the xbc_node.

Thus this changes the array values to use "child" field in
the array case. The reason why split this change is to
test it easily.

Link: https://lkml.kernel.org/r/162262193838.264090.16044473274501498656.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

Revert "lib: Revert use of fallthrough pseudo-keyword in lib/"

This reverts commit 6a9dc5fd6170 ("lib: Revert use of fallthrough
pseudo-keyword in lib/")

Now that we can build arch/powerpc/boot/ fr

Revert "lib: Revert use of fallthrough pseudo-keyword in lib/"

This reverts commit 6a9dc5fd6170 ("lib: Revert use of fallthrough
pseudo-keyword in lib/")

Now that we can build arch/powerpc/boot/ free of -Wimplicit-fallthrough,
re-enable these fixes for lib/.

Signed-off-by: Nick Desaulniers <[email protected]>
Tested-by: Nathan Chancellor <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Reviewed-by: Gustavo A. R. Silva <[email protected]>
Reviewed-by: Miguel Ojeda <[email protected]>
Link: https://github.com/ClangBuiltLinux/linux/issues/236
Signed-off-by: Gustavo A. R. Silva <[email protected]>

show more ...

lib/bootconfig: Fix to remove tailing spaces after value

Fix to remove tailing spaces after value. If there is a space
after value, the bootconfig failed to remove it because it
applies strim() befo

lib/bootconfig: Fix to remove tailing spaces after value

Fix to remove tailing spaces after value. If there is a space
after value, the bootconfig failed to remove it because it
applies strim() before replacing the delimiter with null.

For example,

foo = var # comment

was parsed as below.

foo="var "

but user will expect

foo="var"

This fixes it by applying strim() after removing the delimiter.

Link: https://lkml.kernel.org/r/160068149134.1088739.8868306567670058853.stgit@devnote2

Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support")
Cc: Ingo Molnar <[email protected]>
Cc: [email protected]
Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

lib/bootconfig: Fix a bug of breaking existing tree nodes

Fix a bug of breaking existing tree nodes by parsing the second
and subsequent braces. Since the bootconfig parser uses the
node.next field

lib/bootconfig: Fix a bug of breaking existing tree nodes

Fix a bug of breaking existing tree nodes by parsing the second
and subsequent braces. Since the bootconfig parser uses the
node.next field as a flag of current parent node, but this will
break the existing tree if the same key node is specified again
in the bootconfig.

For example, the following bootconfig should be foo.buz and bar.

foo
bar
foo { buz }

However, when parsing the brace "{", it breaks foo->bar link
by marking open-brace node. So the bootconfig unlinks bar
from the bootconfig internal tree.

This introduces a stack outside of the tree and record the
last open-brace on the stack instead of using node.next field.

Link: https://lkml.kernel.org/r/160068148267.1088739.8264704338030168660.stgit@devnote2

Fixes: 76db5a27a827 ("bootconfig: Add Extra Boot Config support")
Cc: Ingo Molnar <[email protected]>
Cc: [email protected]
Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

show more ...

lib: Revert use of fallthrough pseudo-keyword in lib/

The following build error for powerpc64 was reported by Nathan Chancellor:

"$ scripts/config --file arch/powerpc/configs/powernv_defconfig -e

lib: Revert use of fallthrough pseudo-keyword in lib/

The following build error for powerpc64 was reported by Nathan Chancellor:

"$ scripts/config --file arch/powerpc/configs/powernv_defconfig -e KERNEL_XZ

$ make -skj"$(nproc)" ARCH=powerpc CROSS_COMPILE=powerpc64le-linux- distclean powernv_defconfig zImage
...
In file included from arch/powerpc/boot/../../../lib/decompress_unxz.c:234,
from arch/powerpc/boot/decompress.c:38:
arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c: In function 'dec_main':
arch/powerpc/boot/../../../lib/xz/xz_dec_stream.c:586:4: error: 'fallthrough' undeclared (first use in this function)
586 | fallthrough;
| ^~~~~~~~~~~

This will end up affecting distribution configurations such as Debian
and OpenSUSE according to my testing. I am not sure what the solution
is, the PowerPC wrapper does not set -D__KERNEL__ so I am not sure
that compiler_attributes.h can be safely included."

In order to avoid these sort of problems, it seems that the best
solution is to use /* fall through */ comments instead of the
fallthrough pseudo-keyword macro in lib/, for now.

Reported-by: Nathan Chancellor <[email protected]>
Fixes: df561f6688fe ("treewide: Use fallthrough pseudo-keyword")
Signed-off-by: Gustavo A. R. Silva <[email protected]>
Reviewed-and-tested-by: Nathan Chancellor <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

show more ...

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through mar

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <[email protected]>

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lib/bootconfig: Add override operator support

Add the value override operator (":=") support to the bootconfig.

This value override operator will be useful for the bootloaders
which will only updat

lib/bootconfig: Add override operator support

Add the value override operator (":=") support to the bootconfig.

This value override operator will be useful for the bootloaders
which will only update the existing bootconfig according to the
bootloader boot options.

Without this override operator, the bootloader needs to parse
the existing bootconfig and update it. However, with this
assignment, it can just append the updated (partial) bootconfig
text at the tail of existing one without parsing it.
(Of course, it must update the size, checksum and magic,
but that will be done easily)

Link: https://lkml.kernel.org/r/159482882954.126704.16209517125614438640.stgit@devnote2

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

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