The patch titled
Subject: kheaders: move from proc to sysfs
has been added to the -mm tree. Its filename is
kheaders-move-from-proc-to-sysfs.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/kheaders-move-from-proc-to-sysfs.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/kheaders-move-from-proc-to-sysfs.patch
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------------------------------------------------------
From: "Joel Fernandes (Google)" <joel@xxxxxxxxxxxxxxxxx>
Subject: kheaders: move from proc to sysfs
The kheaders archive consisting of the kernel headers used for compiling
bpf programs is in /proc. However there is concern that moving it here
will make it permanent. Let us move it to /sys/kernel as discussed [1].
[1] https://lore.kernel.org/patchwork/patch/1067310/#1265969
Link: http://lkml.kernel.org/r/20190515213552.203737-2-joel@xxxxxxxxxxxxxxxxx
Signed-off-by: Joel Fernandes (Google) <joel@xxxxxxxxxxxxxxxxx>
Suggested-by: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
init/Kconfig | 15 +++---
kernel/Makefile | 4 -
kernel/gen_ikh_data.sh | 89 ---------------------------------------
kernel/gen_kheaders.sh | 89 +++++++++++++++++++++++++++++++++++++++
kernel/kheaders.c | 40 +++++++----------
5 files changed, 114 insertions(+), 123 deletions(-)
--- a/init/Kconfig~kheaders-move-from-proc-to-sysfs
+++ a/init/Kconfig
@@ -579,15 +579,14 @@ config IKCONFIG_PROC
This option enables access to the kernel configuration file
through /proc/config.gz.
-config IKHEADERS_PROC
- tristate "Enable kernel header artifacts through /proc/kheaders.tar.xz"
- depends on PROC_FS
+config IKHEADERS
+ tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz"
+ depends on SYSFS
help
- This option enables access to the kernel header and other artifacts that
- are generated during the build process. These can be used to build eBPF
- tracing programs, or similar programs. If you build the headers as a
- module, a module called kheaders.ko is built which can be loaded on-demand
- to get access to the headers.
+ This option enables access to the in-kernel headers that are generated during
+ the build process. These can be used to build eBPF tracing programs,
+ or similar programs. If you build the headers as a module, a module called
+ kheaders.ko is built which can be loaded on-demand to get access to headers.
config LOG_BUF_SHIFT
int "Kernel log buffer size (16 => 64KB, 17 => 128KB)"
--- a/kernel/gen_ikh_data.sh
+++ /dev/null
@@ -1,89 +0,0 @@
-#!/bin/bash
-# SPDX-License-Identifier: GPL-2.0
-
-# This script generates an archive consisting of kernel headers
-# for CONFIG_IKHEADERS_PROC.
-set -e
-spath="$(dirname "$(readlink -f "$0")")"
-kroot="$spath/.."
-outdir="$(pwd)"
-tarfile=$1
-cpio_dir=$outdir/$tarfile.tmp
-
-# Script filename relative to the kernel source root
-# We add it to the archive because it is small and any changes
-# to this script will also cause a rebuild of the archive.
-sfile="$(realpath --relative-to $kroot "$(readlink -f "$0")")"
-
-src_file_list="
-include/
-arch/$SRCARCH/include/
-$sfile
-"
-
-obj_file_list="
-include/
-arch/$SRCARCH/include/
-"
-
-# Support incremental builds by skipping archive generation
-# if timestamps of files being archived are not changed.
-
-# This block is useful for debugging the incremental builds.
-# Uncomment it for debugging.
-# iter=1
-# if [ ! -f /tmp/iter ]; then echo 1 > /tmp/iter;
-# else; iter=$(($(cat /tmp/iter) + 1)); fi
-# find $src_file_list -type f | xargs ls -lR > /tmp/src-ls-$iter
-# find $obj_file_list -type f | xargs ls -lR > /tmp/obj-ls-$iter
-
-# include/generated/compile.h is ignored because it is touched even when none
-# of the source files changed. This causes pointless regeneration, so let us
-# ignore them for md5 calculation.
-pushd $kroot > /dev/null
-src_files_md5="$(find $src_file_list -type f |
- grep -v "include/generated/compile.h" |
- xargs ls -lR | md5sum | cut -d ' ' -f1)"
-popd > /dev/null
-obj_files_md5="$(find $obj_file_list -type f |
- grep -v "include/generated/compile.h" |
- xargs ls -lR | md5sum | cut -d ' ' -f1)"
-
-if [ -f $tarfile ]; then tarfile_md5="$(md5sum $tarfile | cut -d ' ' -f1)"; fi
-if [ -f kernel/kheaders.md5 ] &&
- [ "$(cat kernel/kheaders.md5|head -1)" == "$src_files_md5" ] &&
- [ "$(cat kernel/kheaders.md5|head -2|tail -1)" == "$obj_files_md5" ] &&
- [ "$(cat kernel/kheaders.md5|tail -1)" == "$tarfile_md5" ]; then
- exit
-fi
-
-if [ "${quiet}" != "silent_" ]; then
- echo " GEN $tarfile"
-fi
-
-rm -rf $cpio_dir
-mkdir $cpio_dir
-
-pushd $kroot > /dev/null
-for f in $src_file_list;
- do find "$f" ! -name "*.cmd" ! -name ".*";
-done | cpio --quiet -pd $cpio_dir
-popd > /dev/null
-
-# The second CPIO can complain if files already exist which can
-# happen with out of tree builds. Just silence CPIO for now.
-for f in $obj_file_list;
- do find "$f" ! -name "*.cmd" ! -name ".*";
-done | cpio --quiet -pd $cpio_dir >/dev/null 2>&1
-
-# Remove comments except SDPX lines
-find $cpio_dir -type f -print0 |
- xargs -0 -P8 -n1 perl -pi -e 'BEGIN {undef $/;}; s/\/\*((?!SPDX).)*?\*\///smg;'
-
-tar -Jcf $tarfile -C $cpio_dir/ . > /dev/null
-
-echo "$src_files_md5" > kernel/kheaders.md5
-echo "$obj_files_md5" >> kernel/kheaders.md5
-echo "$(md5sum $tarfile | cut -d ' ' -f1)" >> kernel/kheaders.md5
-
-rm -rf $cpio_dir
--- /dev/null
+++ a/kernel/gen_kheaders.sh
@@ -0,0 +1,89 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+
+# This script generates an archive consisting of kernel headers
+# for CONFIG_IKHEADERS.
+set -e
+spath="$(dirname "$(readlink -f "$0")")"
+kroot="$spath/.."
+outdir="$(pwd)"
+tarfile=$1
+cpio_dir=$outdir/$tarfile.tmp
+
+# Script filename relative to the kernel source root
+# We add it to the archive because it is small and any changes
+# to this script will also cause a rebuild of the archive.
+sfile="$(realpath --relative-to $kroot "$(readlink -f "$0")")"
+
+src_file_list="
+include/
+arch/$SRCARCH/include/
+$sfile
+"
+
+obj_file_list="
+include/
+arch/$SRCARCH/include/
+"
+
+# Support incremental builds by skipping archive generation
+# if timestamps of files being archived are not changed.
+
+# This block is useful for debugging the incremental builds.
+# Uncomment it for debugging.
+# iter=1
+# if [ ! -f /tmp/iter ]; then echo 1 > /tmp/iter;
+# else; iter=$(($(cat /tmp/iter) + 1)); fi
+# find $src_file_list -type f | xargs ls -lR > /tmp/src-ls-$iter
+# find $obj_file_list -type f | xargs ls -lR > /tmp/obj-ls-$iter
+
+# include/generated/compile.h is ignored because it is touched even when none
+# of the source files changed. This causes pointless regeneration, so let us
+# ignore them for md5 calculation.
+pushd $kroot > /dev/null
+src_files_md5="$(find $src_file_list -type f |
+ grep -v "include/generated/compile.h" |
+ xargs ls -lR | md5sum | cut -d ' ' -f1)"
+popd > /dev/null
+obj_files_md5="$(find $obj_file_list -type f |
+ grep -v "include/generated/compile.h" |
+ xargs ls -lR | md5sum | cut -d ' ' -f1)"
+
+if [ -f $tarfile ]; then tarfile_md5="$(md5sum $tarfile | cut -d ' ' -f1)"; fi
+if [ -f kernel/kheaders.md5 ] &&
+ [ "$(cat kernel/kheaders.md5|head -1)" == "$src_files_md5" ] &&
+ [ "$(cat kernel/kheaders.md5|head -2|tail -1)" == "$obj_files_md5" ] &&
+ [ "$(cat kernel/kheaders.md5|tail -1)" == "$tarfile_md5" ]; then
+ exit
+fi
+
+if [ "${quiet}" != "silent_" ]; then
+ echo " GEN $tarfile"
+fi
+
+rm -rf $cpio_dir
+mkdir $cpio_dir
+
+pushd $kroot > /dev/null
+for f in $src_file_list;
+ do find "$f" ! -name "*.cmd" ! -name ".*";
+done | cpio --quiet -pd $cpio_dir
+popd > /dev/null
+
+# The second CPIO can complain if files already exist which can
+# happen with out of tree builds. Just silence CPIO for now.
+for f in $obj_file_list;
+ do find "$f" ! -name "*.cmd" ! -name ".*";
+done | cpio --quiet -pd $cpio_dir >/dev/null 2>&1
+
+# Remove comments except SDPX lines
+find $cpio_dir -type f -print0 |
+ xargs -0 -P8 -n1 perl -pi -e 'BEGIN {undef $/;}; s/\/\*((?!SPDX).)*?\*\///smg;'
+
+tar -Jcf $tarfile -C $cpio_dir/ . > /dev/null
+
+echo "$src_files_md5" > kernel/kheaders.md5
+echo "$obj_files_md5" >> kernel/kheaders.md5
+echo "$(md5sum $tarfile | cut -d ' ' -f1)" >> kernel/kheaders.md5
+
+rm -rf $cpio_dir
--- a/kernel/kheaders.c~kheaders-move-from-proc-to-sysfs
+++ a/kernel/kheaders.c
@@ -8,9 +8,8 @@
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/proc_fs.h>
+#include <linux/kobject.h>
#include <linux/init.h>
-#include <linux/uaccess.h>
/*
* Define kernel_headers_data and kernel_headers_data_end, within which the
@@ -31,39 +30,32 @@ extern char kernel_headers_data;
extern char kernel_headers_data_end;
static ssize_t
-ikheaders_read_current(struct file *file, char __user *buf,
- size_t len, loff_t *offset)
+ikheaders_read(struct file *file, struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t off, size_t len)
{
- return simple_read_from_buffer(buf, len, offset,
- &kernel_headers_data,
- &kernel_headers_data_end -
- &kernel_headers_data);
+ memcpy(buf, &kernel_headers_data + off, len);
+ return len;
}
-static const struct file_operations ikheaders_file_ops = {
- .read = ikheaders_read_current,
- .llseek = default_llseek,
+static struct bin_attribute kheaders_attr __ro_after_init = {
+ .attr = {
+ .name = "kheaders.tar.xz",
+ .mode = 0444,
+ },
+ .read = &ikheaders_read,
};
static int __init ikheaders_init(void)
{
- struct proc_dir_entry *entry;
-
- /* create the current headers file */
- entry = proc_create("kheaders.tar.xz", S_IRUGO, NULL,
- &ikheaders_file_ops);
- if (!entry)
- return -ENOMEM;
-
- proc_set_size(entry,
- &kernel_headers_data_end -
- &kernel_headers_data);
- return 0;
+ kheaders_attr.size = (&kernel_headers_data_end -
+ &kernel_headers_data);
+ return sysfs_create_bin_file(kernel_kobj, &kheaders_attr);
}
static void __exit ikheaders_cleanup(void)
{
- remove_proc_entry("kheaders.tar.xz", NULL);
+ sysfs_remove_bin_file(kernel_kobj, &kheaders_attr);
}
module_init(ikheaders_init);
--- a/kernel/Makefile~kheaders-move-from-proc-to-sysfs
+++ a/kernel/Makefile
@@ -71,7 +71,7 @@ obj-$(CONFIG_UTS_NS) += utsname.o
obj-$(CONFIG_USER_NS) += user_namespace.o
obj-$(CONFIG_PID_NS) += pid_namespace.o
obj-$(CONFIG_IKCONFIG) += configs.o
-obj-$(CONFIG_IKHEADERS_PROC) += kheaders.o
+obj-$(CONFIG_IKHEADERS) += kheaders.o
obj-$(CONFIG_SMP) += stop_machine.o
obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
@@ -127,7 +127,7 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG)
$(obj)/kheaders.o: $(obj)/kheaders_data.tar.xz
quiet_cmd_genikh = CHK $(obj)/kheaders_data.tar.xz
-cmd_genikh = $(CONFIG_SHELL) $(srctree)/kernel/gen_ikh_data.sh $@
+cmd_genikh = $(CONFIG_SHELL) $(srctree)/kernel/gen_kheaders.sh $@
$(obj)/kheaders_data.tar.xz: FORCE
$(call cmd,genikh)
_
Patches currently in -mm which might be from joel@xxxxxxxxxxxxxxxxx are
kheaders-move-from-proc-to-sysfs.patch
kheaders-do-not-regenerate-archive-if-config-is-not-changed.patch
convert-struct-pid-count-to-refcount_t.patch
