<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/arch/x86/include/asm/Kbuild, branch docs-next</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=docs-next</id>
<link rel='self' href='http://mirrors.hust.edu.cn/git/lwn.git/atom?h=docs-next'/>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/'/>
<updated>2025-03-19T10:15:11+00:00</updated>
<entry>
<title>x86/cpufeatures: Generate the &lt;asm/cpufeaturemasks.h&gt; header based on build config</title>
<updated>2025-03-19T10:15:11+00:00</updated>
<author>
<name>H. Peter Anvin (Intel)</name>
<email>hpa@zytor.com</email>
</author>
<published>2025-03-05T18:47:22+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=841326332bcb13ae4e6cd456350bf566a402b45e'/>
<id>urn:sha1:841326332bcb13ae4e6cd456350bf566a402b45e</id>
<content type='text'>
Introduce an AWK script to auto-generate the &lt;asm/cpufeaturemasks.h&gt; header
with required and disabled feature masks based on &lt;asm/cpufeatures.h&gt;
and the current build config.

Thus for any CPU feature with a build config, e.g., X86_FRED, simply add:

  config X86_DISABLED_FEATURE_FRED
	def_bool y
	depends on !X86_FRED

to arch/x86/Kconfig.cpufeatures, instead of adding a conditional CPU
feature disable flag, e.g., DISABLE_FRED.

Lastly, the generated required and disabled feature masks will be added to
their corresponding feature masks for this particular compile-time
configuration.

  [ Xin: build integration improvements ]
  [ mingo: Improved changelog and comments ]

Signed-off-by: H. Peter Anvin (Intel) &lt;hpa@zytor.com&gt;
Signed-off-by: Xin Li (Intel) &lt;xin@zytor.com&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Reviewed-by: Nikolay Borisov &lt;nik.borisov@suse.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Link: https://lore.kernel.org/r/20250305184725.3341760-3-xin@zytor.com
</content>
</entry>
<entry>
<title>fprobe: Add fprobe_header encoding feature</title>
<updated>2024-12-26T15:50:05+00:00</updated>
<author>
<name>Masami Hiramatsu (Google)</name>
<email>mhiramat@kernel.org</email>
</author>
<published>2024-12-26T05:14:17+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=b5fa903b7f7c7ffc07430d1380936f72aaf09068'/>
<id>urn:sha1:b5fa903b7f7c7ffc07430d1380936f72aaf09068</id>
<content type='text'>
Fprobe store its data structure address and size on the fgraph return stack
by __fprobe_header. But most 64bit architecture can combine those to
one unsigned long value because 4 MSB in the kernel address are the same.
With this encoding, fprobe can consume less space on ret_stack.

This introduces asm/fprobe.h to define arch dependent encode/decode
macros. Note that since fprobe depends on CONFIG_HAVE_FUNCTION_GRAPH_FREGS,
currently only arm64, loongarch, riscv, s390 and x86 are supported.

Signed-off-by: Masami Hiramatsu (Google) &lt;mhiramat@kernel.org&gt;
Acked-by: Heiko Carstens &lt;hca@linux.ibm.com&gt; # s390
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Alexei Starovoitov &lt;alexei.starovoitov@gmail.com&gt;
Cc: Florent Revest &lt;revest@chromium.org&gt;
Cc: Martin KaFai Lau &lt;martin.lau@linux.dev&gt;
Cc: bpf &lt;bpf@vger.kernel.org&gt;
Cc: Alexei Starovoitov &lt;ast@kernel.org&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alan Maguire &lt;alan.maguire@oracle.com&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Cc: Huacai Chen &lt;chenhuacai@kernel.org&gt;
Cc: WANG Xuerui &lt;kernel@xen0n.name&gt;
Cc: Paul Walmsley &lt;paul.walmsley@sifive.com&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Albert Ou &lt;aou@eecs.berkeley.edu&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Christian Borntraeger &lt;borntraeger@linux.ibm.com&gt;
Cc: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: x86@kernel.org
Cc: "H. Peter Anvin" &lt;hpa@zytor.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Masami Hiramatsu &lt;mhiramat@kernel.org&gt;
Cc: Mathieu Desnoyers &lt;mathieu.desnoyers@efficios.com&gt;
Link: https://lore.kernel.org/173519005783.391279.5307910947400277525.stgit@devnote2
Signed-off-by: Steven Rostedt (Google) &lt;rostedt@goodmis.org&gt;
</content>
</entry>
<entry>
<title>arch, mm: move definition of node_data to generic code</title>
<updated>2024-09-04T04:15:28+00:00</updated>
<author>
<name>Mike Rapoport (Microsoft)</name>
<email>rppt@kernel.org</email>
</author>
<published>2024-08-07T06:40:51+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=46bcce503197d1019ee5c49ccde978e31298e35f'/>
<id>urn:sha1:46bcce503197d1019ee5c49ccde978e31298e35f</id>
<content type='text'>
Every architecture that supports NUMA defines node_data in the same way:

	struct pglist_data *node_data[MAX_NUMNODES];

No reason to keep multiple copies of this definition and its forward
declarations, especially when such forward declaration is the only thing
in include/asm/mmzone.h for many architectures.

Add definition and declaration of node_data to generic code and drop
architecture-specific versions.

Link: https://lkml.kernel.org/r/20240807064110.1003856-8-rppt@kernel.org
Signed-off-by: Mike Rapoport (Microsoft) &lt;rppt@kernel.org&gt;
Acked-by: David Hildenbrand &lt;david@redhat.com&gt;
Reviewed-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Acked-by: Davidlohr Bueso &lt;dave@stgolabs.net&gt;
Tested-by: Zi Yan &lt;ziy@nvidia.com&gt; # for x86_64 and arm64
Tested-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt; [arm64 + CXL via QEMU]
Acked-by: Dan Williams &lt;dan.j.williams@intel.com&gt;
Cc: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
Cc: Andreas Larsson &lt;andreas@gaisler.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: Christophe Leroy &lt;christophe.leroy@csgroup.eu&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: David S. Miller &lt;davem@davemloft.net&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Cc: Huacai Chen &lt;chenhuacai@kernel.org&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Jiaxun Yang &lt;jiaxun.yang@flygoat.com&gt;
Cc: John Paul Adrian Glaubitz &lt;glaubitz@physik.fu-berlin.de&gt;
Cc: Jonathan Corbet &lt;corbet@lwn.net&gt;
Cc: Michael Ellerman &lt;mpe@ellerman.id.au&gt;
Cc: Palmer Dabbelt &lt;palmer@dabbelt.com&gt;
Cc: Rafael J. Wysocki &lt;rafael@kernel.org&gt;
Cc: Rob Herring (Arm) &lt;robh@kernel.org&gt;
Cc: Samuel Holland &lt;samuel.holland@sifive.com&gt;
Cc: Thomas Bogendoerfer &lt;tsbogend@alpha.franken.de&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: Vasily Gorbik &lt;gor@linux.ibm.com&gt;
Cc: Will Deacon &lt;will@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>x86/headers: Remove &lt;asm/export.h&gt;</title>
<updated>2023-10-03T08:38:08+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2023-08-06T14:59:57+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=8b01de80306cbd914be9c45bce30206a49699141'/>
<id>urn:sha1:8b01de80306cbd914be9c45bce30206a49699141</id>
<content type='text'>
All *.S files under arch/x86/ have been converted to include
&lt;linux/export.h&gt; instead of &lt;asm/export.h&gt;.

Remove &lt;asm/export.h&gt;.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lore.kernel.org/r/20230806145958.380314-3-masahiroy@kernel.org
</content>
</entry>
<entry>
<title>x86/unwind/orc: Add ELF section with ORC version identifier</title>
<updated>2023-06-16T15:17:42+00:00</updated>
<author>
<name>Omar Sandoval</name>
<email>osandov@fb.com</email>
</author>
<published>2023-06-13T21:14:56+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=b9f174c811e3ae4ae8959dc57e6adb9990e913f4'/>
<id>urn:sha1:b9f174c811e3ae4ae8959dc57e6adb9990e913f4</id>
<content type='text'>
Commits ffb1b4a41016 ("x86/unwind/orc: Add 'signal' field to ORC
metadata") and fb799447ae29 ("x86,objtool: Split UNWIND_HINT_EMPTY in
two") changed the ORC format. Although ORC is internal to the kernel,
it's the only way for external tools to get reliable kernel stack traces
on x86-64. In particular, the drgn debugger [1] uses ORC for stack
unwinding, and these format changes broke it [2]. As the drgn
maintainer, I don't care how often or how much the kernel changes the
ORC format as long as I have a way to detect the change.

It suffices to store a version identifier in the vmlinux and kernel
module ELF files (to use when parsing ORC sections from ELF), and in
kernel memory (to use when parsing ORC from a core dump+symbol table).
Rather than hard-coding a version number that needs to be manually
bumped, Peterz suggested hashing the definitions from orc_types.h. If
there is a format change that isn't caught by this, the hashing script
can be updated.

This patch adds an .orc_header allocated ELF section containing the
20-byte hash to vmlinux and kernel modules, along with the corresponding
__start_orc_header and __stop_orc_header symbols in vmlinux.

1: https://github.com/osandov/drgn
2: https://github.com/osandov/drgn/issues/303

Fixes: ffb1b4a41016 ("x86/unwind/orc: Add 'signal' field to ORC metadata")
Fixes: fb799447ae29 ("x86,objtool: Split UNWIND_HINT_EMPTY in two")
Signed-off-by: Omar Sandoval &lt;osandov@fb.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Acked-by: Josh Poimboeuf &lt;jpoimboe@kernel.org&gt;
Link: https://lkml.kernel.org/r/aef9c8dc43915b886a8c48509a12ec1b006ca1ca.1686690801.git.osandov@osandov.com
</content>
</entry>
<entry>
<title>x86/syscalls: Switch to generic syscalltbl.sh</title>
<updated>2021-05-20T13:03:58+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2021-05-17T07:38:10+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=6218d0f6b8dece1f2e82f0a47a0e6b8ecb631ef6'/>
<id>urn:sha1:6218d0f6b8dece1f2e82f0a47a0e6b8ecb631ef6</id>
<content type='text'>
Many architectures duplicate similar shell scripts.

Convert x86 and UML to use scripts/syscalltbl.sh. The generic script
generates seperate headers for x86/64 and x86/x32 syscalls, while the x86
specific script coalesced them into one. Adjust the code accordingly.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Link: https://lore.kernel.org/r/20210517073815.97426-3-masahiroy@kernel.org
</content>
</entry>
<entry>
<title>asm-generic: make more kernel-space headers mandatory</title>
<updated>2020-04-02T16:35:25+00:00</updated>
<author>
<name>Masahiro Yamada</name>
<email>masahiroy@kernel.org</email>
</author>
<published>2020-04-02T04:03:12+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=630f289b7114c0e68519cbd634e2b7ec804ca8c5'/>
<id>urn:sha1:630f289b7114c0e68519cbd634e2b7ec804ca8c5</id>
<content type='text'>
Change a header to mandatory-y if both of the following are met:

[1] At least one architecture (except um) specifies it as generic-y in
    arch/*/include/asm/Kbuild

[2] Every architecture (except um) either has its own implementation
    (arch/*/include/asm/*.h) or specifies it as generic-y in
    arch/*/include/asm/Kbuild

This commit was generated by the following shell script.

-----------------------------------&gt;8-----------------------------------

arches=$(cd arch; ls -1 | sed -e '/Kconfig/d' -e '/um/d')

tmpfile=$(mktemp)

grep "^mandatory-y +=" include/asm-generic/Kbuild &gt; $tmpfile

find arch -path 'arch/*/include/asm/Kbuild' |
	xargs sed -n 's/^generic-y += \(.*\)/\1/p' | sort -u |
while read header
do
	mandatory=yes

	for arch in $arches
	do
		if ! grep -q "generic-y += $header" arch/$arch/include/asm/Kbuild &amp;&amp;
			! [ -f arch/$arch/include/asm/$header ]; then
			mandatory=no
			break
		fi
	done

	if [ "$mandatory" = yes ]; then
		echo "mandatory-y += $header" &gt;&gt; $tmpfile

		for arch in $arches
		do
			sed -i "/generic-y += $header/d" arch/$arch/include/asm/Kbuild
		done
	fi

done

sed -i '/^mandatory-y +=/d' include/asm-generic/Kbuild

LANG=C sort $tmpfile &gt;&gt; include/asm-generic/Kbuild

-----------------------------------&gt;8-----------------------------------

One obvious benefit is the diff stat:

 25 files changed, 52 insertions(+), 557 deletions(-)

It is tedious to list generic-y for each arch that needs it.

So, mandatory-y works like a fallback default (by just wrapping
asm-generic one) when arch does not have a specific header
implementation.

See the following commits:

def3f7cefe4e81c296090e1722a76551142c227c
a1b39bae16a62ce4aae02d958224f19316d98b24

It is tedious to convert headers one by one, so I processed by a shell
script.

Signed-off-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Signed-off-by: Andrew Morton &lt;akpm@linux-foundation.org&gt;
Cc: Michal Simek &lt;michal.simek@xilinx.com&gt;
Cc: Christoph Hellwig &lt;hch@lst.de&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Link: http://lkml.kernel.org/r/20200210175452.5030-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>asm-generic: Make dma-contiguous.h a mandatory include/asm header</title>
<updated>2020-02-04T10:38:59+00:00</updated>
<author>
<name>Michal Simek</name>
<email>michal.simek@xilinx.com</email>
</author>
<published>2020-01-17T07:48:17+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=def3f7cefe4e81c296090e1722a76551142c227c'/>
<id>urn:sha1:def3f7cefe4e81c296090e1722a76551142c227c</id>
<content type='text'>
dma-continuguous.h is generic for all architectures except arm32 which has
its own version.

Similar change was done for msi.h by commit a1b39bae16a6
("asm-generic: Make msi.h a mandatory include/asm header")

Suggested-by: Christoph Hellwig &lt;hch@infradead.org&gt;
Link: https://lore.kernel.org/linux-arm-kernel/20200117080446.GA8980@lst.de/T/#m92bb56b04161057635d4142e1b3b9b6b0a70122e
Signed-off-by: Michal Simek &lt;michal.simek@xilinx.com&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Acked-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Acked-by: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Paul Walmsley &lt;paul.walmsley@sifive.com&gt; # for arch/riscv

</content>
</entry>
<entry>
<title>treewide: Add SPDX license identifier - Kbuild</title>
<updated>2019-05-30T18:32:33+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2019-05-30T12:03:44+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=96ac6d435100450f0565708d9b885ea2a7400e0a'/>
<id>urn:sha1:96ac6d435100450f0565708d9b885ea2a7400e0a</id>
<content type='text'>
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

      GPL-2.0

Reported-by: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Reviewed-by: Kate Stewart &lt;kstewart@linuxfoundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>arch: Use asm-generic header for asm/mmiowb.h</title>
<updated>2019-04-08T10:59:43+00:00</updated>
<author>
<name>Will Deacon</name>
<email>will.deacon@arm.com</email>
</author>
<published>2019-02-22T12:49:41+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=fdcd06a8ab775cbe716ff893372bed580e4c8a1c'/>
<id>urn:sha1:fdcd06a8ab775cbe716ff893372bed580e4c8a1c</id>
<content type='text'>
Hook up asm-generic/mmiowb.h to Kbuild for all architectures so that we
can subsequently include asm/mmiowb.h from core code.

Cc: Masahiro Yamada &lt;yamada.masahiro@socionext.com&gt;
Cc: Arnd Bergmann &lt;arnd@arndb.de&gt;
Acked-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Will Deacon &lt;will.deacon@arm.com&gt;
</content>
</entry>
</feed>
