diff mbox

[v8,03/13] kexec_file, x86, powerpc: factor out kexec_file_ops functions

Message ID 20180222111732.23051-4-takahiro.akashi@linaro.org (mailing list archive)
State New, archived
Headers show

Commit Message

AKASHI Takahiro Feb. 22, 2018, 11:17 a.m. UTC
As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup()
and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops
array and now duplicated among some architectures, let's factor them out.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/kexec.h            |  2 +-
 arch/powerpc/kernel/kexec_elf_64.c          |  2 +-
 arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------
 arch/x86/include/asm/kexec-bzimage64.h      |  2 +-
 arch/x86/kernel/kexec-bzimage64.c           |  2 +-
 arch/x86/kernel/machine_kexec_64.c          | 45 +----------------------
 include/linux/kexec.h                       | 15 ++++----
 kernel/kexec_file.c                         | 57 +++++++++++++++++++++++++++--
 8 files changed, 70 insertions(+), 94 deletions(-)

Comments

Dave Young Feb. 23, 2018, 9:24 a.m. UTC | #1
Hi AKASHI,

On 02/22/18 at 08:17pm, AKASHI Takahiro wrote:
> As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup()
> and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops
> array and now duplicated among some architectures, let's factor them out.
> 
> Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> Cc: Dave Young <dyoung@redhat.com>
> Cc: Vivek Goyal <vgoyal@redhat.com>
> Cc: Baoquan He <bhe@redhat.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
> ---
>  arch/powerpc/include/asm/kexec.h            |  2 +-
>  arch/powerpc/kernel/kexec_elf_64.c          |  2 +-
>  arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------
>  arch/x86/include/asm/kexec-bzimage64.h      |  2 +-
>  arch/x86/kernel/kexec-bzimage64.c           |  2 +-
>  arch/x86/kernel/machine_kexec_64.c          | 45 +----------------------
>  include/linux/kexec.h                       | 15 ++++----
>  kernel/kexec_file.c                         | 57 +++++++++++++++++++++++++++--
>  8 files changed, 70 insertions(+), 94 deletions(-)
> 

[snip]

> diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> index 990adae52151..a6d14a768b3e 100644
> --- a/kernel/kexec_file.c
> +++ b/kernel/kexec_file.c
> @@ -26,34 +26,83 @@
>  #include <linux/vmalloc.h>
>  #include "kexec_internal.h"
>  
> +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL};
> +
>  #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
>  static int kexec_calculate_store_digests(struct kimage *image);
>  #else
>  static int kexec_calculate_store_digests(struct kimage *image) { return 0; };
>  #endif
>  
> +int _kexec_kernel_image_probe(struct kimage *image, void *buf,
> +			     unsigned long buf_len)
> +{
> +	const struct kexec_file_ops * const *fops;
> +	int ret = -ENOEXEC;
> +
> +	for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
> +		ret = (*fops)->probe(buf, buf_len);
> +		if (!ret) {
> +			image->fops = *fops;
> +			return ret;
> +		}
> +	}
> +
> +	return ret;
> +}
> +
>  /* Architectures can provide this probe function */
>  int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
>  					 unsigned long buf_len)
>  {
> -	return -ENOEXEC;
> +	return _kexec_kernel_image_probe(image, buf, buf_len);


I vaguely remember previously I suggest split the _kexec_kernel_image_probe
because arch code can call them, and common code also use it like above.
But in your new series I do not find where else calls this function
except the common code arch_kexec_kernel_image_probe.  If nobody use
them then it is not worth to split them out, it is better to just embed
them in the __weak functions.

Ditto for other similar functions.

[snip]

Thanks
Dave
AKASHI Takahiro Feb. 26, 2018, 10:01 a.m. UTC | #2
On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote:
> Hi AKASHI,
> 
> On 02/22/18 at 08:17pm, AKASHI Takahiro wrote:
> > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup()
> > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops
> > array and now duplicated among some architectures, let's factor them out.
> > 
> > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > Cc: Dave Young <dyoung@redhat.com>
> > Cc: Vivek Goyal <vgoyal@redhat.com>
> > Cc: Baoquan He <bhe@redhat.com>
> > Cc: Michael Ellerman <mpe@ellerman.id.au>
> > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
> > ---
> >  arch/powerpc/include/asm/kexec.h            |  2 +-
> >  arch/powerpc/kernel/kexec_elf_64.c          |  2 +-
> >  arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------
> >  arch/x86/include/asm/kexec-bzimage64.h      |  2 +-
> >  arch/x86/kernel/kexec-bzimage64.c           |  2 +-
> >  arch/x86/kernel/machine_kexec_64.c          | 45 +----------------------
> >  include/linux/kexec.h                       | 15 ++++----
> >  kernel/kexec_file.c                         | 57 +++++++++++++++++++++++++++--
> >  8 files changed, 70 insertions(+), 94 deletions(-)
> > 
> 
> [snip]
> 
> > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> > index 990adae52151..a6d14a768b3e 100644
> > --- a/kernel/kexec_file.c
> > +++ b/kernel/kexec_file.c
> > @@ -26,34 +26,83 @@
> >  #include <linux/vmalloc.h>
> >  #include "kexec_internal.h"
> >  
> > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL};
> > +
> >  #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
> >  static int kexec_calculate_store_digests(struct kimage *image);
> >  #else
> >  static int kexec_calculate_store_digests(struct kimage *image) { return 0; };
> >  #endif
> >  
> > +int _kexec_kernel_image_probe(struct kimage *image, void *buf,
> > +			     unsigned long buf_len)
> > +{
> > +	const struct kexec_file_ops * const *fops;
> > +	int ret = -ENOEXEC;
> > +
> > +	for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
> > +		ret = (*fops)->probe(buf, buf_len);
> > +		if (!ret) {
> > +			image->fops = *fops;
> > +			return ret;
> > +		}
> > +	}
> > +
> > +	return ret;
> > +}
> > +
> >  /* Architectures can provide this probe function */
> >  int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> >  					 unsigned long buf_len)
> >  {
> > -	return -ENOEXEC;
> > +	return _kexec_kernel_image_probe(image, buf, buf_len);
> 
> 
> I vaguely remember previously I suggest split the _kexec_kernel_image_probe
> because arch code can call them, and common code also use it like above.
> But in your new series I do not find where else calls this function
> except the common code arch_kexec_kernel_image_probe.  If nobody use
> them then it is not worth to split them out, it is better to just embed
> them in the __weak functions.

Powerpc's arch_kexec_kernel_image_probe() uses
_kexec_kekrnel_image_probe() as it needs an extra check to rule out
crash dump for now.

Thanks,
-Takahiro AKASHI


> Ditto for other similar functions.
> 
> [snip]
> 
> Thanks
> Dave
Philipp Rudo Feb. 26, 2018, 11:25 a.m. UTC | #3
On Mon, 26 Feb 2018 19:01:39 +0900
AKASHI Takahiro <takahiro.akashi@linaro.org> wrote:

> On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote:
> > Hi AKASHI,
> > 
> > On 02/22/18 at 08:17pm, AKASHI Takahiro wrote:  
> > > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup()
> > > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops
> > > array and now duplicated among some architectures, let's factor them out.
> > > 
> > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > > Cc: Dave Young <dyoung@redhat.com>
> > > Cc: Vivek Goyal <vgoyal@redhat.com>
> > > Cc: Baoquan He <bhe@redhat.com>
> > > Cc: Michael Ellerman <mpe@ellerman.id.au>
> > > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
> > > ---
> > >  arch/powerpc/include/asm/kexec.h            |  2 +-
> > >  arch/powerpc/kernel/kexec_elf_64.c          |  2 +-
> > >  arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------
> > >  arch/x86/include/asm/kexec-bzimage64.h      |  2 +-
> > >  arch/x86/kernel/kexec-bzimage64.c           |  2 +-
> > >  arch/x86/kernel/machine_kexec_64.c          | 45 +----------------------
> > >  include/linux/kexec.h                       | 15 ++++----
> > >  kernel/kexec_file.c                         | 57 +++++++++++++++++++++++++++--
> > >  8 files changed, 70 insertions(+), 94 deletions(-)
> > >   
> > 
> > [snip]
> >   
> > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> > > index 990adae52151..a6d14a768b3e 100644
> > > --- a/kernel/kexec_file.c
> > > +++ b/kernel/kexec_file.c
> > > @@ -26,34 +26,83 @@
> > >  #include <linux/vmalloc.h>
> > >  #include "kexec_internal.h"
> > >  
> > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL};
> > > +
> > >  #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
> > >  static int kexec_calculate_store_digests(struct kimage *image);
> > >  #else
> > >  static int kexec_calculate_store_digests(struct kimage *image) { return 0; };
> > >  #endif
> > >  
> > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf,
> > > +			     unsigned long buf_len)
> > > +{
> > > +	const struct kexec_file_ops * const *fops;
> > > +	int ret = -ENOEXEC;
> > > +
> > > +	for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
> > > +		ret = (*fops)->probe(buf, buf_len);
> > > +		if (!ret) {
> > > +			image->fops = *fops;
> > > +			return ret;
> > > +		}
> > > +	}
> > > +
> > > +	return ret;
> > > +}
> > > +
> > >  /* Architectures can provide this probe function */
> > >  int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> > >  					 unsigned long buf_len)
> > >  {
> > > -	return -ENOEXEC;
> > > +	return _kexec_kernel_image_probe(image, buf, buf_len);  
> > 
> > 
> > I vaguely remember previously I suggest split the _kexec_kernel_image_probe
> > because arch code can call them, and common code also use it like above.
> > But in your new series I do not find where else calls this function
> > except the common code arch_kexec_kernel_image_probe.  If nobody use
> > them then it is not worth to split them out, it is better to just embed
> > them in the __weak functions.  
> 
> Powerpc's arch_kexec_kernel_image_probe() uses
> _kexec_kekrnel_image_probe() as it needs an extra check to rule out
> crash dump for now.

s390 has to use it too. We have to write to a fixed address in the buffer. So
we need to check if the buffer is large enough to write to that address.

Philipp
 
> Thanks,
> -Takahiro AKASHI
> 
> 
> > Ditto for other similar functions.
> > 
> > [snip]
> > 
> > Thanks
> > Dave  
> 
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
>
Dave Young Feb. 28, 2018, 12:38 p.m. UTC | #4
On 02/26/18 at 07:01pm, AKASHI Takahiro wrote:
> On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote:
> > Hi AKASHI,
> > 
> > On 02/22/18 at 08:17pm, AKASHI Takahiro wrote:
> > > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup()
> > > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops
> > > array and now duplicated among some architectures, let's factor them out.
> > > 
> > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > > Cc: Dave Young <dyoung@redhat.com>
> > > Cc: Vivek Goyal <vgoyal@redhat.com>
> > > Cc: Baoquan He <bhe@redhat.com>
> > > Cc: Michael Ellerman <mpe@ellerman.id.au>
> > > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
> > > ---
> > >  arch/powerpc/include/asm/kexec.h            |  2 +-
> > >  arch/powerpc/kernel/kexec_elf_64.c          |  2 +-
> > >  arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------
> > >  arch/x86/include/asm/kexec-bzimage64.h      |  2 +-
> > >  arch/x86/kernel/kexec-bzimage64.c           |  2 +-
> > >  arch/x86/kernel/machine_kexec_64.c          | 45 +----------------------
> > >  include/linux/kexec.h                       | 15 ++++----
> > >  kernel/kexec_file.c                         | 57 +++++++++++++++++++++++++++--
> > >  8 files changed, 70 insertions(+), 94 deletions(-)
> > > 
> > 
> > [snip]
> > 
> > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> > > index 990adae52151..a6d14a768b3e 100644
> > > --- a/kernel/kexec_file.c
> > > +++ b/kernel/kexec_file.c
> > > @@ -26,34 +26,83 @@
> > >  #include <linux/vmalloc.h>
> > >  #include "kexec_internal.h"
> > >  
> > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL};
> > > +
> > >  #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
> > >  static int kexec_calculate_store_digests(struct kimage *image);
> > >  #else
> > >  static int kexec_calculate_store_digests(struct kimage *image) { return 0; };
> > >  #endif
> > >  
> > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf,
> > > +			     unsigned long buf_len)
> > > +{
> > > +	const struct kexec_file_ops * const *fops;
> > > +	int ret = -ENOEXEC;
> > > +
> > > +	for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
> > > +		ret = (*fops)->probe(buf, buf_len);
> > > +		if (!ret) {
> > > +			image->fops = *fops;
> > > +			return ret;
> > > +		}
> > > +	}
> > > +
> > > +	return ret;
> > > +}
> > > +
> > >  /* Architectures can provide this probe function */
> > >  int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> > >  					 unsigned long buf_len)
> > >  {
> > > -	return -ENOEXEC;
> > > +	return _kexec_kernel_image_probe(image, buf, buf_len);
> > 
> > 
> > I vaguely remember previously I suggest split the _kexec_kernel_image_probe
> > because arch code can call them, and common code also use it like above.
> > But in your new series I do not find where else calls this function
> > except the common code arch_kexec_kernel_image_probe.  If nobody use
> > them then it is not worth to split them out, it is better to just embed
> > them in the __weak functions.
> 
> Powerpc's arch_kexec_kernel_image_probe() uses
> _kexec_kekrnel_image_probe() as it needs an extra check to rule out
> crash dump for now.

Oops, I missed that, but what about other similar functions? Such as:
_kexec_kernel_image_load
_kimage_file_post_load_cleanup
_kexec_kernel_verify_sig

> 
> Thanks,
> -Takahiro AKASHI
> 
> 
> > Ditto for other similar functions.
> > 
> > [snip]
> > 
> > Thanks
> > Dave

Thanks
Dave
AKASHI Takahiro March 1, 2018, 3:18 a.m. UTC | #5
On Wed, Feb 28, 2018 at 08:38:00PM +0800, Dave Young wrote:
> On 02/26/18 at 07:01pm, AKASHI Takahiro wrote:
> > On Fri, Feb 23, 2018 at 05:24:59PM +0800, Dave Young wrote:
> > > Hi AKASHI,
> > > 
> > > On 02/22/18 at 08:17pm, AKASHI Takahiro wrote:
> > > > As arch_kexec_kernel_*_{probe,load}(), arch_kimage_file_post_load_cleanup()
> > > > and arch_kexec_kernel_verify_sg can be parameterized with a kexec_file_ops
> > > > array and now duplicated among some architectures, let's factor them out.
> > > > 
> > > > Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
> > > > Cc: Dave Young <dyoung@redhat.com>
> > > > Cc: Vivek Goyal <vgoyal@redhat.com>
> > > > Cc: Baoquan He <bhe@redhat.com>
> > > > Cc: Michael Ellerman <mpe@ellerman.id.au>
> > > > Cc: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
> > > > ---
> > > >  arch/powerpc/include/asm/kexec.h            |  2 +-
> > > >  arch/powerpc/kernel/kexec_elf_64.c          |  2 +-
> > > >  arch/powerpc/kernel/machine_kexec_file_64.c | 39 ++------------------
> > > >  arch/x86/include/asm/kexec-bzimage64.h      |  2 +-
> > > >  arch/x86/kernel/kexec-bzimage64.c           |  2 +-
> > > >  arch/x86/kernel/machine_kexec_64.c          | 45 +----------------------
> > > >  include/linux/kexec.h                       | 15 ++++----
> > > >  kernel/kexec_file.c                         | 57 +++++++++++++++++++++++++++--
> > > >  8 files changed, 70 insertions(+), 94 deletions(-)
> > > > 
> > > 
> > > [snip]
> > > 
> > > > diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
> > > > index 990adae52151..a6d14a768b3e 100644
> > > > --- a/kernel/kexec_file.c
> > > > +++ b/kernel/kexec_file.c
> > > > @@ -26,34 +26,83 @@
> > > >  #include <linux/vmalloc.h>
> > > >  #include "kexec_internal.h"
> > > >  
> > > > +const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL};
> > > > +
> > > >  #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
> > > >  static int kexec_calculate_store_digests(struct kimage *image);
> > > >  #else
> > > >  static int kexec_calculate_store_digests(struct kimage *image) { return 0; };
> > > >  #endif
> > > >  
> > > > +int _kexec_kernel_image_probe(struct kimage *image, void *buf,
> > > > +			     unsigned long buf_len)
> > > > +{
> > > > +	const struct kexec_file_ops * const *fops;
> > > > +	int ret = -ENOEXEC;
> > > > +
> > > > +	for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
> > > > +		ret = (*fops)->probe(buf, buf_len);
> > > > +		if (!ret) {
> > > > +			image->fops = *fops;
> > > > +			return ret;
> > > > +		}
> > > > +	}
> > > > +
> > > > +	return ret;
> > > > +}
> > > > +
> > > >  /* Architectures can provide this probe function */
> > > >  int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
> > > >  					 unsigned long buf_len)
> > > >  {
> > > > -	return -ENOEXEC;
> > > > +	return _kexec_kernel_image_probe(image, buf, buf_len);
> > > 
> > > 
> > > I vaguely remember previously I suggest split the _kexec_kernel_image_probe
> > > because arch code can call them, and common code also use it like above.
> > > But in your new series I do not find where else calls this function
> > > except the common code arch_kexec_kernel_image_probe.  If nobody use
> > > them then it is not worth to split them out, it is better to just embed
> > > them in the __weak functions.
> > 
> > Powerpc's arch_kexec_kernel_image_probe() uses
> > _kexec_kekrnel_image_probe() as it needs an extra check to rule out
> > crash dump for now.
> 
> Oops, I missed that, but what about other similar functions? Such as:
> _kexec_kernel_image_load
> _kimage_file_post_load_cleanup
> _kexec_kernel_verify_sig

Current no users.
Given those functions are so simple, we could go either way.

-Takahiro AKASHI


> > 
> > Thanks,
> > -Takahiro AKASHI
> > 
> > 
> > > Ditto for other similar functions.
> > > 
> > > [snip]
> > > 
> > > Thanks
> > > Dave
> 
> Thanks
> Dave
diff mbox

Patch

diff --git a/arch/powerpc/include/asm/kexec.h b/arch/powerpc/include/asm/kexec.h
index d8b1e8e7e035..4a585cba1787 100644
--- a/arch/powerpc/include/asm/kexec.h
+++ b/arch/powerpc/include/asm/kexec.h
@@ -95,7 +95,7 @@  static inline bool kdump_in_progress(void)
 }
 
 #ifdef CONFIG_KEXEC_FILE
-extern struct kexec_file_ops kexec_elf64_ops;
+extern const struct kexec_file_ops kexec_elf64_ops;
 
 #ifdef CONFIG_IMA_KEXEC
 #define ARCH_HAS_KIMAGE_ARCH
diff --git a/arch/powerpc/kernel/kexec_elf_64.c b/arch/powerpc/kernel/kexec_elf_64.c
index 9a42309b091a..6c78c11c7faf 100644
--- a/arch/powerpc/kernel/kexec_elf_64.c
+++ b/arch/powerpc/kernel/kexec_elf_64.c
@@ -657,7 +657,7 @@  static void *elf64_load(struct kimage *image, char *kernel_buf,
 	return ret ? ERR_PTR(ret) : fdt;
 }
 
-struct kexec_file_ops kexec_elf64_ops = {
+const struct kexec_file_ops kexec_elf64_ops = {
 	.probe = elf64_probe,
 	.load = elf64_load,
 };
diff --git a/arch/powerpc/kernel/machine_kexec_file_64.c b/arch/powerpc/kernel/machine_kexec_file_64.c
index e4395f937d63..a27ec647350c 100644
--- a/arch/powerpc/kernel/machine_kexec_file_64.c
+++ b/arch/powerpc/kernel/machine_kexec_file_64.c
@@ -31,52 +31,19 @@ 
 
 #define SLAVE_CODE_SIZE		256
 
-static struct kexec_file_ops *kexec_file_loaders[] = {
+const struct kexec_file_ops * const kexec_file_loaders[] = {
 	&kexec_elf64_ops,
+	NULL
 };
 
 int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
 				  unsigned long buf_len)
 {
-	int i, ret = -ENOEXEC;
-	struct kexec_file_ops *fops;
-
 	/* We don't support crash kernels yet. */
 	if (image->type == KEXEC_TYPE_CRASH)
 		return -ENOTSUPP;
 
-	for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) {
-		fops = kexec_file_loaders[i];
-		if (!fops || !fops->probe)
-			continue;
-
-		ret = fops->probe(buf, buf_len);
-		if (!ret) {
-			image->fops = fops;
-			return ret;
-		}
-	}
-
-	return ret;
-}
-
-void *arch_kexec_kernel_image_load(struct kimage *image)
-{
-	if (!image->fops || !image->fops->load)
-		return ERR_PTR(-ENOEXEC);
-
-	return image->fops->load(image, image->kernel_buf,
-				 image->kernel_buf_len, image->initrd_buf,
-				 image->initrd_buf_len, image->cmdline_buf,
-				 image->cmdline_buf_len);
-}
-
-int arch_kimage_file_post_load_cleanup(struct kimage *image)
-{
-	if (!image->fops || !image->fops->cleanup)
-		return 0;
-
-	return image->fops->cleanup(image->image_loader_data);
+	return _kexec_kernel_image_probe(image, buf, buf_len);
 }
 
 /**
diff --git a/arch/x86/include/asm/kexec-bzimage64.h b/arch/x86/include/asm/kexec-bzimage64.h
index 9f07cff43705..df89ee7d3e9e 100644
--- a/arch/x86/include/asm/kexec-bzimage64.h
+++ b/arch/x86/include/asm/kexec-bzimage64.h
@@ -2,6 +2,6 @@ 
 #ifndef _ASM_KEXEC_BZIMAGE64_H
 #define _ASM_KEXEC_BZIMAGE64_H
 
-extern struct kexec_file_ops kexec_bzImage64_ops;
+extern const struct kexec_file_ops kexec_bzImage64_ops;
 
 #endif  /* _ASM_KEXE_BZIMAGE64_H */
diff --git a/arch/x86/kernel/kexec-bzimage64.c b/arch/x86/kernel/kexec-bzimage64.c
index fb095ba0c02f..705654776c0c 100644
--- a/arch/x86/kernel/kexec-bzimage64.c
+++ b/arch/x86/kernel/kexec-bzimage64.c
@@ -538,7 +538,7 @@  static int bzImage64_verify_sig(const char *kernel, unsigned long kernel_len)
 }
 #endif
 
-struct kexec_file_ops kexec_bzImage64_ops = {
+const struct kexec_file_ops kexec_bzImage64_ops = {
 	.probe = bzImage64_probe,
 	.load = bzImage64_load,
 	.cleanup = bzImage64_cleanup,
diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 1f790cf9d38f..2cdd29d64181 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -30,8 +30,9 @@ 
 #include <asm/set_memory.h>
 
 #ifdef CONFIG_KEXEC_FILE
-static struct kexec_file_ops *kexec_file_loaders[] = {
+const struct kexec_file_ops * const kexec_file_loaders[] = {
 		&kexec_bzImage64_ops,
+		NULL
 };
 #endif
 
@@ -363,27 +364,6 @@  void arch_crash_save_vmcoreinfo(void)
 /* arch-dependent functionality related to kexec file-based syscall */
 
 #ifdef CONFIG_KEXEC_FILE
-int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
-				  unsigned long buf_len)
-{
-	int i, ret = -ENOEXEC;
-	struct kexec_file_ops *fops;
-
-	for (i = 0; i < ARRAY_SIZE(kexec_file_loaders); i++) {
-		fops = kexec_file_loaders[i];
-		if (!fops || !fops->probe)
-			continue;
-
-		ret = fops->probe(buf, buf_len);
-		if (!ret) {
-			image->fops = fops;
-			return ret;
-		}
-	}
-
-	return ret;
-}
-
 void *arch_kexec_kernel_image_load(struct kimage *image)
 {
 	vfree(image->arch.elf_headers);
@@ -398,27 +378,6 @@  void *arch_kexec_kernel_image_load(struct kimage *image)
 				 image->cmdline_buf_len);
 }
 
-int arch_kimage_file_post_load_cleanup(struct kimage *image)
-{
-	if (!image->fops || !image->fops->cleanup)
-		return 0;
-
-	return image->fops->cleanup(image->image_loader_data);
-}
-
-#ifdef CONFIG_KEXEC_VERIFY_SIG
-int arch_kexec_kernel_verify_sig(struct kimage *image, void *kernel,
-				 unsigned long kernel_len)
-{
-	if (!image->fops || !image->fops->verify_sig) {
-		pr_debug("kernel loader does not support signature verification.");
-		return -EKEYREJECTED;
-	}
-
-	return image->fops->verify_sig(kernel, kernel_len);
-}
-#endif
-
 /*
  * Apply purgatory relocations.
  *
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index f16f6ceb3875..325980537125 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -209,7 +209,7 @@  struct kimage {
 	unsigned long cmdline_buf_len;
 
 	/* File operations provided by image loader */
-	struct kexec_file_ops *fops;
+	const struct kexec_file_ops *fops;
 
 	/* Image loader handling the kernel can store a pointer here */
 	void *image_loader_data;
@@ -277,12 +277,13 @@  int crash_shrink_memory(unsigned long new_size);
 size_t crash_get_memory_size(void);
 void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 
-int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
-					 unsigned long buf_len);
-void * __weak arch_kexec_kernel_image_load(struct kimage *image);
-int __weak arch_kimage_file_post_load_cleanup(struct kimage *image);
-int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
-					unsigned long buf_len);
+int _kexec_kernel_image_probe(struct kimage *image, void *buf,
+			      unsigned long buf_len);
+void *_kexec_kernel_image_load(struct kimage *image);
+int _kimage_file_post_load_cleanup(struct kimage *image);
+int _kexec_kernel_verify_sig(struct kimage *image, void *buf,
+			     unsigned long buf_len);
+
 int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
 					Elf_Shdr *sechdrs, unsigned int relsec);
 int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c
index 990adae52151..a6d14a768b3e 100644
--- a/kernel/kexec_file.c
+++ b/kernel/kexec_file.c
@@ -26,34 +26,83 @@ 
 #include <linux/vmalloc.h>
 #include "kexec_internal.h"
 
+const __weak struct kexec_file_ops * const kexec_file_loaders[] = {NULL};
+
 #ifdef CONFIG_ARCH_HAS_KEXEC_PURGATORY
 static int kexec_calculate_store_digests(struct kimage *image);
 #else
 static int kexec_calculate_store_digests(struct kimage *image) { return 0; };
 #endif
 
+int _kexec_kernel_image_probe(struct kimage *image, void *buf,
+			     unsigned long buf_len)
+{
+	const struct kexec_file_ops * const *fops;
+	int ret = -ENOEXEC;
+
+	for (fops = &kexec_file_loaders[0]; *fops && (*fops)->probe; ++fops) {
+		ret = (*fops)->probe(buf, buf_len);
+		if (!ret) {
+			image->fops = *fops;
+			return ret;
+		}
+	}
+
+	return ret;
+}
+
 /* Architectures can provide this probe function */
 int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
 					 unsigned long buf_len)
 {
-	return -ENOEXEC;
+	return _kexec_kernel_image_probe(image, buf, buf_len);
+}
+
+void *_kexec_kernel_image_load(struct kimage *image)
+{
+	if (!image->fops || !image->fops->load)
+		return ERR_PTR(-ENOEXEC);
+
+	return image->fops->load(image, image->kernel_buf,
+				 image->kernel_buf_len, image->initrd_buf,
+				 image->initrd_buf_len, image->cmdline_buf,
+				 image->cmdline_buf_len);
 }
 
 void * __weak arch_kexec_kernel_image_load(struct kimage *image)
 {
-	return ERR_PTR(-ENOEXEC);
+	return _kexec_kernel_image_load(image);
+}
+
+int _kimage_file_post_load_cleanup(struct kimage *image)
+{
+	if (!image->fops || !image->fops->cleanup)
+		return 0;
+
+	return image->fops->cleanup(image->image_loader_data);
 }
 
 int __weak arch_kimage_file_post_load_cleanup(struct kimage *image)
 {
-	return -EINVAL;
+	return _kimage_file_post_load_cleanup(image);
 }
 
 #ifdef CONFIG_KEXEC_VERIFY_SIG
+int _kexec_kernel_verify_sig(struct kimage *image, void *buf,
+			    unsigned long buf_len)
+{
+	if (!image->fops || !image->fops->verify_sig) {
+		pr_debug("kernel loader does not support signature verification.\n");
+		return -EKEYREJECTED;
+	}
+
+	return image->fops->verify_sig(buf, buf_len);
+}
+
 int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 					unsigned long buf_len)
 {
-	return -EKEYREJECTED;
+	return _kexec_kernel_verify_sig(image, buf, buf_len);
 }
 #endif