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
Suggested-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org --- This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/
v1->v2: Fixed some kconfig nits (Masami).
init/Kconfig | 16 ++++----- kernel/Makefile | 4 +-- kernel/{gen_ikh_data.sh => gen_kheaders.sh} | 2 +- kernel/kheaders.c | 40 +++++++++------------ 4 files changed, 26 insertions(+), 36 deletions(-) rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%)
diff --git a/init/Kconfig b/init/Kconfig index 26a364a95b57..c3661991b089 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -579,15 +579,13 @@ 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 - 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. +config IKHEADERS + tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz" + help + 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)" diff --git a/kernel/Makefile b/kernel/Makefile index 12399614c350..b32a558fae2f 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -70,7 +70,7 @@ 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 @@ -126,7 +126,7 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE $(obj)/kheaders.o: $(obj)/kheaders_data.tar.xz
quiet_cmd_genikh = CHK $(obj)/kheaders_data.tar.xz -cmd_genikh = $(srctree)/kernel/gen_ikh_data.sh $@ +cmd_genikh = $(srctree)/kernel/gen_kheaders.sh $@ $(obj)/kheaders_data.tar.xz: FORCE $(call cmd,genikh)
diff --git a/kernel/gen_ikh_data.sh b/kernel/gen_kheaders.sh similarity index 98% rename from kernel/gen_ikh_data.sh rename to kernel/gen_kheaders.sh index 591a94f7b387..581b83534587 100755 --- a/kernel/gen_ikh_data.sh +++ b/kernel/gen_kheaders.sh @@ -2,7 +2,7 @@ # SPDX-License-Identifier: GPL-2.0
# This script generates an archive consisting of kernel headers -# for CONFIG_IKHEADERS_PROC. +# for CONFIG_IKHEADERS. set -e spath="$(dirname "$(readlink -f "$0")")" kroot="$spath/.." diff --git a/kernel/kheaders.c b/kernel/kheaders.c index 70ae6052920d..6a16f8f6898d 100644 --- a/kernel/kheaders.c +++ b/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 = S_IRUGO, + }, + .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);
On Sat, May 04, 2019 at 08:12:13AM -0400, Joel Fernandes (Google) wrote:
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
Suggested-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org
This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/
v1->v2: Fixed some kconfig nits (Masami).
init/Kconfig | 16 ++++----- kernel/Makefile | 4 +-- kernel/{gen_ikh_data.sh => gen_kheaders.sh} | 2 +- kernel/kheaders.c | 40 +++++++++------------ 4 files changed, 26 insertions(+), 36 deletions(-) rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%)
diff --git a/init/Kconfig b/init/Kconfig index 26a364a95b57..c3661991b089 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -579,15 +579,13 @@ 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
- help
This option enables access to the kernel header and other artifacts thatare generated during the build process. These can be used to build eBPFtracing programs, or similar programs. If you build the headers as amodule, a module called kheaders.ko is built which can be loaded on-demandto get access to the headers.+config IKHEADERS
- tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz"
- help
This option enables access to the in-kernel headers that are generated duringthe build process. These can be used to build eBPF tracing programs,or similar programs. If you build the headers as a module, a module calledkheaders.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)" diff --git a/kernel/Makefile b/kernel/Makefile index 12399614c350..b32a558fae2f 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -70,7 +70,7 @@ 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
Good in changing the config name, I hadn't thought of that.
diff --git a/kernel/gen_ikh_data.sh b/kernel/gen_kheaders.sh similarity index 98% rename from kernel/gen_ikh_data.sh rename to kernel/gen_kheaders.sh
Same here, nice.
-static const struct file_operations ikheaders_file_ops = {
- .read = ikheaders_read_current,
- .llseek = default_llseek,
+static struct bin_attribute kheaders_attr __ro_after_init = {
Minor nit, are you sure about __ro_after_init for an attribute structure? Is it even needed?
- .attr = {
.name = "kheaders.tar.xz",.mode = S_IRUGO,- },
- .read = &ikheaders_read,
};
BIN_ATTR_RO? Ah, no, that will not work with the name of the file, nevermind.
But, you should change S_IRUGO to the correct octal number, checkpatch should have barfed on this change.
thanks,
greg k-h
On Sat, May 04, 2019 at 02:21:58PM +0200, Greg KH wrote:
On Sat, May 04, 2019 at 08:12:13AM -0400, Joel Fernandes (Google) wrote:
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
Suggested-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org
This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/
v1->v2: Fixed some kconfig nits (Masami).
init/Kconfig | 16 ++++----- kernel/Makefile | 4 +-- kernel/{gen_ikh_data.sh => gen_kheaders.sh} | 2 +- kernel/kheaders.c | 40 +++++++++------------ 4 files changed, 26 insertions(+), 36 deletions(-) rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%)
diff --git a/init/Kconfig b/init/Kconfig index 26a364a95b57..c3661991b089 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -579,15 +579,13 @@ 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
- help
This option enables access to the kernel header and other artifacts thatare generated during the build process. These can be used to build eBPFtracing programs, or similar programs. If you build the headers as amodule, a module called kheaders.ko is built which can be loaded on-demandto get access to the headers.+config IKHEADERS
- tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz"
- help
This option enables access to the in-kernel headers that are generated duringthe build process. These can be used to build eBPF tracing programs,or similar programs. If you build the headers as a module, a module calledkheaders.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)" diff --git a/kernel/Makefile b/kernel/Makefile index 12399614c350..b32a558fae2f 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -70,7 +70,7 @@ 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
Good in changing the config name, I hadn't thought of that.
diff --git a/kernel/gen_ikh_data.sh b/kernel/gen_kheaders.sh similarity index 98% rename from kernel/gen_ikh_data.sh rename to kernel/gen_kheaders.sh
Same here, nice.
Thanks.
-static const struct file_operations ikheaders_file_ops = {
- .read = ikheaders_read_current,
- .llseek = default_llseek,
+static struct bin_attribute kheaders_attr __ro_after_init = {
Minor nit, are you sure about __ro_after_init for an attribute structure? Is it even needed?
Yes, because after init, we don't need to change it, so it makes it more robust to accidental overwrite. We change it on init because we have to calculate the size of the archive. I was following this from kernel/ksysfs.c actually.
I have recently encountered this mechanism in the module loader as well while doing an RCU patch. The module loader post init will mark the page as read-only and any writes to it will fault. These variables will be placed in a ".data.ro_after_init" or a similarly named section in the module ELF.
But, you should change S_IRUGO to the correct octal number, checkpatch should have barfed on this change.
fixed, below is the updated patch inline, thanks!
---8<-----------------------
From: "Joel Fernandes (Google)" joel@joelfernandes.org Subject: [PATCH v3] 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
Suggested-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org --- This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/
v2->v3: Fixed sysfs file mode nit (Greg). v1->v2: Fixed some kconfig nits (Masami).
Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org --- init/Kconfig | 16 ++++----- kernel/Makefile | 4 +-- kernel/{gen_ikh_data.sh => gen_kheaders.sh} | 2 +- kernel/kheaders.c | 40 +++++++++------------ 4 files changed, 26 insertions(+), 36 deletions(-) rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%)
diff --git a/init/Kconfig b/init/Kconfig index 26a364a95b57..c3661991b089 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -579,15 +579,13 @@ 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 - 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. +config IKHEADERS + tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz" + help + 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)" diff --git a/kernel/Makefile b/kernel/Makefile index 12399614c350..b32a558fae2f 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -70,7 +70,7 @@ 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 @@ -126,7 +126,7 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE $(obj)/kheaders.o: $(obj)/kheaders_data.tar.xz
quiet_cmd_genikh = CHK $(obj)/kheaders_data.tar.xz -cmd_genikh = $(srctree)/kernel/gen_ikh_data.sh $@ +cmd_genikh = $(srctree)/kernel/gen_kheaders.sh $@ $(obj)/kheaders_data.tar.xz: FORCE $(call cmd,genikh)
diff --git a/kernel/gen_ikh_data.sh b/kernel/gen_kheaders.sh similarity index 98% rename from kernel/gen_ikh_data.sh rename to kernel/gen_kheaders.sh index 591a94f7b387..581b83534587 100755 --- a/kernel/gen_ikh_data.sh +++ b/kernel/gen_kheaders.sh @@ -2,7 +2,7 @@ # SPDX-License-Identifier: GPL-2.0
# This script generates an archive consisting of kernel headers -# for CONFIG_IKHEADERS_PROC. +# for CONFIG_IKHEADERS. set -e spath="$(dirname "$(readlink -f "$0")")" kroot="$spath/.." diff --git a/kernel/kheaders.c b/kernel/kheaders.c index 70ae6052920d..8f69772af77b 100644 --- a/kernel/kheaders.c +++ b/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);
On Sat, May 04, 2019 at 08:36:50AM -0400, Joel Fernandes wrote:
But, you should change S_IRUGO to the correct octal number, checkpatch should have barfed on this change.
fixed, below is the updated patch inline, thanks!
Please resend as a "real" submission, doing so in this format is a bit more difficult to apply.
thanks,
greg k-h
On Sun, May 05, 2019 at 11:10:30AM +0200, Greg KH wrote:
On Sat, May 04, 2019 at 08:36:50AM -0400, Joel Fernandes wrote:
But, you should change S_IRUGO to the correct octal number, checkpatch should have barfed on this change.
fixed, below is the updated patch inline, thanks!
Please resend as a "real" submission, doing so in this format is a bit more difficult to apply.
git am --scissors can do it, but no problem I will send as a formal submission. Thanks a lot.
thanks,
greg k-h
On Sun, 5 May 2019 13:26:23 +0000 Joel Fernandes joel@joelfernandes.org wrote:
On Sun, May 05, 2019 at 11:10:30AM +0200, Greg KH wrote:
On Sat, May 04, 2019 at 08:36:50AM -0400, Joel Fernandes wrote:
But, you should change S_IRUGO to the correct octal number, checkpatch should have barfed on this change.
fixed, below is the updated patch inline, thanks!
Please resend as a "real" submission, doing so in this format is a bit more difficult to apply.
git am --scissors can do it, but no problem I will send as a formal submission. Thanks a lot.
True, but a lot of us depend on scripts to pull in patches from our INBOX. Which is why we like them to stay with the standard format.
-- Steve
On Sun, May 05, 2019 at 04:31:45PM -0400, Steven Rostedt wrote:
On Sun, 5 May 2019 13:26:23 +0000 Joel Fernandes joel@joelfernandes.org wrote:
On Sun, May 05, 2019 at 11:10:30AM +0200, Greg KH wrote:
On Sat, May 04, 2019 at 08:36:50AM -0400, Joel Fernandes wrote:
But, you should change S_IRUGO to the correct octal number, checkpatch should have barfed on this change.
fixed, below is the updated patch inline, thanks!
Please resend as a "real" submission, doing so in this format is a bit more difficult to apply.
git am --scissors can do it, but no problem I will send as a formal submission. Thanks a lot.
True, but a lot of us depend on scripts to pull in patches from our INBOX. Which is why we like them to stay with the standard format.
Thanks makes sense. So Greg, I submitted this properly, does it look good to you now? Steven, I would appreciate any Acks/Reviews on the patch as well: https://lore.kernel.org/patchwork/patch/1070199/
- Joel
On Tue, May 07, 2019 at 12:38:24PM -0400, Joel Fernandes wrote:
On Sun, May 05, 2019 at 04:31:45PM -0400, Steven Rostedt wrote:
On Sun, 5 May 2019 13:26:23 +0000 Joel Fernandes joel@joelfernandes.org wrote:
On Sun, May 05, 2019 at 11:10:30AM +0200, Greg KH wrote:
On Sat, May 04, 2019 at 08:36:50AM -0400, Joel Fernandes wrote:
But, you should change S_IRUGO to the correct octal number, checkpatch should have barfed on this change.
fixed, below is the updated patch inline, thanks!
Please resend as a "real" submission, doing so in this format is a bit more difficult to apply.
git am --scissors can do it, but no problem I will send as a formal submission. Thanks a lot.
True, but a lot of us depend on scripts to pull in patches from our INBOX. Which is why we like them to stay with the standard format.
Thanks makes sense. So Greg, I submitted this properly, does it look good to you now? Steven, I would appreciate any Acks/Reviews on the patch as well: https://lore.kernel.org/patchwork/patch/1070199/
Looks good to me, should get to it in a few days...
On Tue, 7 May 2019 18:57:18 +0200 Greg KH gregkh@linuxfoundation.org wrote:
Thanks makes sense. So Greg, I submitted this properly, does it look good to you now? Steven, I would appreciate any Acks/Reviews on the patch as well: https://lore.kernel.org/patchwork/patch/1070199/
Looks good to me, should get to it in a few days...
Me too. Feel free to add
Acked-by: Steven Rostedt (VMware) rostedt@goodmis.org
But as for reviewing, I see nothing wrong with it, but I doubt I'll find something that Greg missed in this code.
-- Steve
On Tue, May 07, 2019 at 01:03:33PM -0400, Steven Rostedt wrote:
On Tue, 7 May 2019 18:57:18 +0200 Greg KH gregkh@linuxfoundation.org wrote:
Thanks makes sense. So Greg, I submitted this properly, does it look good to you now? Steven, I would appreciate any Acks/Reviews on the patch as well: https://lore.kernel.org/patchwork/patch/1070199/
Looks good to me, should get to it in a few days...
Me too. Feel free to add
Acked-by: Steven Rostedt (VMware) rostedt@goodmis.org
But as for reviewing, I see nothing wrong with it, but I doubt I'll find something that Greg missed in this code.
Thanks!
- Joel
On Sat, May 4, 2019 at 9:26 PM Joel Fernandes (Google) joel@joelfernandes.org wrote:
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
Suggested-by: Steven Rostedt rostedt@goodmis.org Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org
This patch applies on top of the previous patch that was applied to the driver tree: https://lore.kernel.org/patchwork/patch/1067310/
v1->v2: Fixed some kconfig nits (Masami).
My name is Masahiro, just in case.
init/Kconfig | 16 ++++----- kernel/Makefile | 4 +-- kernel/{gen_ikh_data.sh => gen_kheaders.sh} | 2 +- kernel/kheaders.c | 40 +++++++++------------ 4 files changed, 26 insertions(+), 36 deletions(-) rename kernel/{gen_ikh_data.sh => gen_kheaders.sh} (98%)
diff --git a/init/Kconfig b/init/Kconfig index 26a364a95b57..c3661991b089 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -579,15 +579,13 @@ 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_FShelpThis option enables access to the kernel header and other artifacts thatare generated during the build process. These can be used to build eBPFtracing programs, or similar programs. If you build the headers as amodule, a module called kheaders.ko is built which can be loaded on-demandto get access to the headers.+config IKHEADERS
tristate "Enable kernel headers through /sys/kernel/kheaders.tar.xz"
In v1, I suggested to change "depends on PROC_FS" to "depends on SYSFS".
fs/sysfs/ must be compiled to make this feature work.
helpThis option enables access to the in-kernel headers that are generated duringthe 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
While you are touching the help, could you make the number of spaces between sentences consistent?
Thanks.
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)" diff --git a/kernel/Makefile b/kernel/Makefile index 12399614c350..b32a558fae2f 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -70,7 +70,7 @@ 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 @@ -126,7 +126,7 @@ $(obj)/config_data.gz: $(KCONFIG_CONFIG) FORCE $(obj)/kheaders.o: $(obj)/kheaders_data.tar.xz
quiet_cmd_genikh = CHK $(obj)/kheaders_data.tar.xz -cmd_genikh = $(srctree)/kernel/gen_ikh_data.sh $@ +cmd_genikh = $(srctree)/kernel/gen_kheaders.sh $@ $(obj)/kheaders_data.tar.xz: FORCE $(call cmd,genikh)
diff --git a/kernel/gen_ikh_data.sh b/kernel/gen_kheaders.sh similarity index 98% rename from kernel/gen_ikh_data.sh rename to kernel/gen_kheaders.sh index 591a94f7b387..581b83534587 100755 --- a/kernel/gen_ikh_data.sh +++ b/kernel/gen_kheaders.sh @@ -2,7 +2,7 @@ # SPDX-License-Identifier: GPL-2.0
# This script generates an archive consisting of kernel headers -# for CONFIG_IKHEADERS_PROC. +# for CONFIG_IKHEADERS. set -e spath="$(dirname "$(readlink -f "$0")")" kroot="$spath/.." diff --git a/kernel/kheaders.c b/kernel/kheaders.c index 70ae6052920d..6a16f8f6898d 100644 --- a/kernel/kheaders.c +++ b/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 = S_IRUGO,},.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);
2.21.0.1020.gf2820cf01a-goog
-- Best Regards
Masahiro Yamada
linux-kselftest-mirror@lists.linaro.org
-
Greg KH -
Joel Fernandes -
Joel Fernandes (Google)
-
Masahiro Yamada -
Steven Rostedt