diff mbox series

[4/7] x86: kexec_file: remove X86_64 dependency from prepare_elf64_headers()

Message ID 20180227044814.24808-5-takahiro.akashi@linaro.org
State Superseded
Headers show
Series kexec_file: refactoring for other architecutres | expand

Commit Message

AKASHI Takahiro Feb. 27, 2018, 4:48 a.m. UTC 
The code guarded by CONFIG_X86_64 is necessary on some architectures
which have a dedicated kernel mapping outside of linear memory mapping.
(arm64 is among those.)

In this patch, an additional argument, kernel_map, is added to enable/
disable the code removing #ifdef.

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>
---
 arch/x86/kernel/crash.c | 25 +++++++++++++------------
 1 file changed, 13 insertions(+), 12 deletions(-)

-- 
2.16.2

Comments

Dave Young March 2, 2018, 5:19 a.m. UTC | #1 
On 02/27/18 at 01:48pm, AKASHI Takahiro wrote:
> The code guarded by CONFIG_X86_64 is necessary on some architectures

> which have a dedicated kernel mapping outside of linear memory mapping.

> (arm64 is among those.)

> 

> In this patch, an additional argument, kernel_map, is added to enable/

> disable the code removing #ifdef.

> 

> 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>

> ---

>  arch/x86/kernel/crash.c | 25 +++++++++++++------------

>  1 file changed, 13 insertions(+), 12 deletions(-)

> 

> diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c

> index 2123fa0efc17..913fd8021f8a 100644

> --- a/arch/x86/kernel/crash.c

> +++ b/arch/x86/kernel/crash.c

> @@ -347,7 +347,7 @@ static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg)

>  	return 0;

>  }

>  

> -static int prepare_elf64_headers(struct crash_elf_data *ced,

> +static int prepare_elf64_headers(struct crash_elf_data *ced, int kernel_map,

>  		void **addr, unsigned long *sz)

>  {

>  	Elf64_Ehdr *ehdr;

> @@ -414,17 +414,17 @@ static int prepare_elf64_headers(struct crash_elf_data *ced,

>  	phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;

>  	(ehdr->e_phnum)++;

>  

> -#ifdef CONFIG_X86_64

>  	/* Prepare PT_LOAD type program header for kernel text region */

> -	phdr = (Elf64_Phdr *)bufp;

> -	bufp += sizeof(Elf64_Phdr);

> -	phdr->p_type = PT_LOAD;

> -	phdr->p_flags = PF_R|PF_W|PF_X;

> -	phdr->p_vaddr = (Elf64_Addr)_text;

> -	phdr->p_filesz = phdr->p_memsz = _end - _text;

> -	phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);

> -	(ehdr->e_phnum)++;

> -#endif

> +	if (kernel_map) {

> +		phdr = (Elf64_Phdr *)bufp;

> +		bufp += sizeof(Elf64_Phdr);

> +		phdr->p_type = PT_LOAD;

> +		phdr->p_flags = PF_R|PF_W|PF_X;

> +		phdr->p_vaddr = (Elf64_Addr)_text;

> +		phdr->p_filesz = phdr->p_memsz = _end - _text;

> +		phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);

> +		(ehdr->e_phnum)++;

> +	}

>  

>  	/* Go through all the ranges in cmem->ranges[] and prepare phdr */

>  	for (i = 0; i < cmem->nr_ranges; i++) {

> @@ -477,7 +477,8 @@ static int prepare_elf_headers(struct kimage *image, void **addr,

>  		goto out;

>  

>  	/* By default prepare 64bit headers */

> -	ret =  prepare_elf64_headers(ced, addr, sz);

> +	ret =  prepare_elf64_headers(ced,

> +				(int)IS_ENABLED(CONFIG_X86_64), addr, sz);


A bool would be enough for kernel_map

>  	if (ret)

>  		goto out;

>  


Thanks
Dave
> -- 

> 2.16.2

>
AKASHI Takahiro March 2, 2018, 5:33 a.m. UTC | #2 
On Fri, Mar 02, 2018 at 01:19:56PM +0800, Dave Young wrote:
> On 02/27/18 at 01:48pm, AKASHI Takahiro wrote:

> > The code guarded by CONFIG_X86_64 is necessary on some architectures

> > which have a dedicated kernel mapping outside of linear memory mapping.

> > (arm64 is among those.)

> > 

> > In this patch, an additional argument, kernel_map, is added to enable/

> > disable the code removing #ifdef.

> > 

> > 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>

> > ---

> >  arch/x86/kernel/crash.c | 25 +++++++++++++------------

> >  1 file changed, 13 insertions(+), 12 deletions(-)

> > 

> > diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c

> > index 2123fa0efc17..913fd8021f8a 100644

> > --- a/arch/x86/kernel/crash.c

> > +++ b/arch/x86/kernel/crash.c

> > @@ -347,7 +347,7 @@ static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg)

> >  	return 0;

> >  }

> >  

> > -static int prepare_elf64_headers(struct crash_elf_data *ced,

> > +static int prepare_elf64_headers(struct crash_elf_data *ced, int kernel_map,

> >  		void **addr, unsigned long *sz)

> >  {

> >  	Elf64_Ehdr *ehdr;

> > @@ -414,17 +414,17 @@ static int prepare_elf64_headers(struct crash_elf_data *ced,

> >  	phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;

> >  	(ehdr->e_phnum)++;

> >  

> > -#ifdef CONFIG_X86_64

> >  	/* Prepare PT_LOAD type program header for kernel text region */

> > -	phdr = (Elf64_Phdr *)bufp;

> > -	bufp += sizeof(Elf64_Phdr);

> > -	phdr->p_type = PT_LOAD;

> > -	phdr->p_flags = PF_R|PF_W|PF_X;

> > -	phdr->p_vaddr = (Elf64_Addr)_text;

> > -	phdr->p_filesz = phdr->p_memsz = _end - _text;

> > -	phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);

> > -	(ehdr->e_phnum)++;

> > -#endif

> > +	if (kernel_map) {

> > +		phdr = (Elf64_Phdr *)bufp;

> > +		bufp += sizeof(Elf64_Phdr);

> > +		phdr->p_type = PT_LOAD;

> > +		phdr->p_flags = PF_R|PF_W|PF_X;

> > +		phdr->p_vaddr = (Elf64_Addr)_text;

> > +		phdr->p_filesz = phdr->p_memsz = _end - _text;

> > +		phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);

> > +		(ehdr->e_phnum)++;

> > +	}

> >  

> >  	/* Go through all the ranges in cmem->ranges[] and prepare phdr */

> >  	for (i = 0; i < cmem->nr_ranges; i++) {

> > @@ -477,7 +477,8 @@ static int prepare_elf_headers(struct kimage *image, void **addr,

> >  		goto out;

> >  

> >  	/* By default prepare 64bit headers */

> > -	ret =  prepare_elf64_headers(ced, addr, sz);

> > +	ret =  prepare_elf64_headers(ced,

> > +				(int)IS_ENABLED(CONFIG_X86_64), addr, sz);

> 

> A bool would be enough for kernel_map


Yeah, for now.
What I thought of is that we might want to extend its functionality
in the future as I did here for kernel_map without changing its interface.
But I'd defer to you.

-Takahiro AKASHI

> >  	if (ret)

> >  		goto out;

> >  

> 

> Thanks

> Dave

> > -- 

> > 2.16.2

> >
diff mbox series

Patch

diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index 2123fa0efc17..913fd8021f8a 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -347,7 +347,7 @@  static int prepare_elf64_ram_headers_callback(struct resource *res, void *arg)
 	return 0;
 }
 
-static int prepare_elf64_headers(struct crash_elf_data *ced,
+static int prepare_elf64_headers(struct crash_elf_data *ced, int kernel_map,
 		void **addr, unsigned long *sz)
 {
 	Elf64_Ehdr *ehdr;
@@ -414,17 +414,17 @@  static int prepare_elf64_headers(struct crash_elf_data *ced,
 	phdr->p_filesz = phdr->p_memsz = VMCOREINFO_NOTE_SIZE;
 	(ehdr->e_phnum)++;
 
-#ifdef CONFIG_X86_64
 	/* Prepare PT_LOAD type program header for kernel text region */
-	phdr = (Elf64_Phdr *)bufp;
-	bufp += sizeof(Elf64_Phdr);
-	phdr->p_type = PT_LOAD;
-	phdr->p_flags = PF_R|PF_W|PF_X;
-	phdr->p_vaddr = (Elf64_Addr)_text;
-	phdr->p_filesz = phdr->p_memsz = _end - _text;
-	phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
-	(ehdr->e_phnum)++;
-#endif
+	if (kernel_map) {
+		phdr = (Elf64_Phdr *)bufp;
+		bufp += sizeof(Elf64_Phdr);
+		phdr->p_type = PT_LOAD;
+		phdr->p_flags = PF_R|PF_W|PF_X;
+		phdr->p_vaddr = (Elf64_Addr)_text;
+		phdr->p_filesz = phdr->p_memsz = _end - _text;
+		phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
+		(ehdr->e_phnum)++;
+	}
 
 	/* Go through all the ranges in cmem->ranges[] and prepare phdr */
 	for (i = 0; i < cmem->nr_ranges; i++) {
@@ -477,7 +477,8 @@  static int prepare_elf_headers(struct kimage *image, void **addr,
 		goto out;
 
 	/* By default prepare 64bit headers */
-	ret =  prepare_elf64_headers(ced, addr, sz);
+	ret =  prepare_elf64_headers(ced,
+				(int)IS_ENABLED(CONFIG_X86_64), addr, sz);
 	if (ret)
 		goto out;