* [PATCH -v2 3/8] kexec jump: check code size in control page
@ 2008-08-08 6:52 ` Huang Ying
0 siblings, 0 replies; 6+ messages in thread
From: Huang Ying @ 2008-08-08 6:52 UTC (permalink / raw)
To: Eric W. Biederman, Pavel Machek, nigel, Rafael J. Wysocki,
Andrew Morton, Vivek Goyal, mingo, Linus Torvalds
Cc: Kexec Mailing List, linux-kernel
Kexec/Kexec-jump require code size in control page is less than
PAGE_SIZE/2. This patch add link-time checking for this.
ASSERT() of ld link script is used as the link-time checking
mechanism.
Signed-off-by: Huang Ying <ying.huang@intel.com>
---
arch/x86/kernel/machine_kexec_32.c | 2 +-
arch/x86/kernel/relocate_kernel_32.S | 10 +++++++---
arch/x86/kernel/vmlinux_32.lds.S | 2 ++
arch/x86/kernel/vmlinux_check_32.lds.S | 7 +++++++
include/asm-x86/kexec.h | 4 ++++
5 files changed, 21 insertions(+), 4 deletions(-)
--- a/arch/x86/kernel/machine_kexec_32.c
+++ b/arch/x86/kernel/machine_kexec_32.c
@@ -138,7 +138,7 @@ void machine_kexec(struct kimage *image)
}
control_page = page_address(image->control_code_page);
- memcpy(control_page, relocate_kernel, PAGE_SIZE/2);
+ memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE);
relocate_kernel_ptr = control_page;
page_list[PA_CONTROL_PAGE] = __pa(control_page);
--- a/arch/x86/kernel/relocate_kernel_32.S
+++ b/arch/x86/kernel/relocate_kernel_32.S
@@ -20,10 +20,11 @@
#define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
#define PAE_PGD_ATTR (_PAGE_PRESENT)
-/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are
- * used to save some data for jumping back
+/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE
+ * ~ control_page + PAGE_SIZE * 3/4 are used to save some data for
+ * jumping back
*/
-#define DATA(offset) (PAGE_SIZE/2+(offset))
+#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset))
/* Minimal CPU state */
#define ESP DATA(0x0)
@@ -376,3 +377,6 @@ swap_pages:
popl %ebx
popl %ebp
ret
+
+ .globl kexec_control_code_size
+.set kexec_control_code_size, . - relocate_kernel
--- a/include/asm-x86/kexec.h
+++ b/include/asm-x86/kexec.h
@@ -41,6 +41,10 @@
# define PAGES_NR 17
#endif
+#ifdef CONFIG_X86_32
+# define KEXEC_CONTROL_CODE_MAX_SIZE 2048
+#endif
+
#ifndef __ASSEMBLY__
#include <linux/string.h>
--- a/arch/x86/kernel/vmlinux_32.lds.S
+++ b/arch/x86/kernel/vmlinux_32.lds.S
@@ -209,3 +209,5 @@ SECTIONS
DWARF_DEBUG
}
+
+#include "vmlinux_check_32.lds.S"
--- /dev/null
+++ b/arch/x86/kernel/vmlinux_check_32.lds.S
@@ -0,0 +1,7 @@
+/*
+ * Link time checks
+ */
+
+#include <asm/kexec.h>
+
+ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE, "kexec control code size is too big")
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH -v2 3/8] kexec jump: check code size in control page
@ 2008-08-08 6:52 ` Huang Ying
0 siblings, 0 replies; 6+ messages in thread
From: Huang Ying @ 2008-08-08 6:52 UTC (permalink / raw)
To: Eric W. Biederman, Pavel Machek, nigel, Rafael J. Wysocki,
Andrew Morton, Vivek Goyal, mingo, Linus Torvalds
Cc: linux-kernel, Kexec Mailing List
Kexec/Kexec-jump require code size in control page is less than
PAGE_SIZE/2. This patch add link-time checking for this.
ASSERT() of ld link script is used as the link-time checking
mechanism.
Signed-off-by: Huang Ying <ying.huang@intel.com>
---
arch/x86/kernel/machine_kexec_32.c | 2 +-
arch/x86/kernel/relocate_kernel_32.S | 10 +++++++---
arch/x86/kernel/vmlinux_32.lds.S | 2 ++
arch/x86/kernel/vmlinux_check_32.lds.S | 7 +++++++
include/asm-x86/kexec.h | 4 ++++
5 files changed, 21 insertions(+), 4 deletions(-)
--- a/arch/x86/kernel/machine_kexec_32.c
+++ b/arch/x86/kernel/machine_kexec_32.c
@@ -138,7 +138,7 @@ void machine_kexec(struct kimage *image)
}
control_page = page_address(image->control_code_page);
- memcpy(control_page, relocate_kernel, PAGE_SIZE/2);
+ memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE);
relocate_kernel_ptr = control_page;
page_list[PA_CONTROL_PAGE] = __pa(control_page);
--- a/arch/x86/kernel/relocate_kernel_32.S
+++ b/arch/x86/kernel/relocate_kernel_32.S
@@ -20,10 +20,11 @@
#define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
#define PAE_PGD_ATTR (_PAGE_PRESENT)
-/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are
- * used to save some data for jumping back
+/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE
+ * ~ control_page + PAGE_SIZE * 3/4 are used to save some data for
+ * jumping back
*/
-#define DATA(offset) (PAGE_SIZE/2+(offset))
+#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset))
/* Minimal CPU state */
#define ESP DATA(0x0)
@@ -376,3 +377,6 @@ swap_pages:
popl %ebx
popl %ebp
ret
+
+ .globl kexec_control_code_size
+.set kexec_control_code_size, . - relocate_kernel
--- a/include/asm-x86/kexec.h
+++ b/include/asm-x86/kexec.h
@@ -41,6 +41,10 @@
# define PAGES_NR 17
#endif
+#ifdef CONFIG_X86_32
+# define KEXEC_CONTROL_CODE_MAX_SIZE 2048
+#endif
+
#ifndef __ASSEMBLY__
#include <linux/string.h>
--- a/arch/x86/kernel/vmlinux_32.lds.S
+++ b/arch/x86/kernel/vmlinux_32.lds.S
@@ -209,3 +209,5 @@ SECTIONS
DWARF_DEBUG
}
+
+#include "vmlinux_check_32.lds.S"
--- /dev/null
+++ b/arch/x86/kernel/vmlinux_check_32.lds.S
@@ -0,0 +1,7 @@
+/*
+ * Link time checks
+ */
+
+#include <asm/kexec.h>
+
+ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE, "kexec control code size is too big")
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH -v2 3/8] kexec jump: check code size in control page
2008-08-08 6:52 ` Huang Ying
@ 2008-08-08 14:09 ` Vivek Goyal
-1 siblings, 0 replies; 6+ messages in thread
From: Vivek Goyal @ 2008-08-08 14:09 UTC (permalink / raw)
To: Huang Ying
Cc: nigel, Kexec Mailing List, linux-kernel, Rafael J. Wysocki,
Eric W. Biederman, Pavel Machek, Andrew Morton, Linus Torvalds,
mingo
On Fri, Aug 08, 2008 at 02:52:36PM +0800, Huang Ying wrote:
> Kexec/Kexec-jump require code size in control page is less than
> PAGE_SIZE/2. This patch add link-time checking for this.
>
> ASSERT() of ld link script is used as the link-time checking
> mechanism.
>
> Signed-off-by: Huang Ying <ying.huang@intel.com>
>
> ---
> arch/x86/kernel/machine_kexec_32.c | 2 +-
> arch/x86/kernel/relocate_kernel_32.S | 10 +++++++---
> arch/x86/kernel/vmlinux_32.lds.S | 2 ++
> arch/x86/kernel/vmlinux_check_32.lds.S | 7 +++++++
> include/asm-x86/kexec.h | 4 ++++
> 5 files changed, 21 insertions(+), 4 deletions(-)
>
> --- a/arch/x86/kernel/machine_kexec_32.c
> +++ b/arch/x86/kernel/machine_kexec_32.c
> @@ -138,7 +138,7 @@ void machine_kexec(struct kimage *image)
> }
>
> control_page = page_address(image->control_code_page);
> - memcpy(control_page, relocate_kernel, PAGE_SIZE/2);
> + memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE);
>
> relocate_kernel_ptr = control_page;
> page_list[PA_CONTROL_PAGE] = __pa(control_page);
> --- a/arch/x86/kernel/relocate_kernel_32.S
> +++ b/arch/x86/kernel/relocate_kernel_32.S
> @@ -20,10 +20,11 @@
> #define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
> #define PAE_PGD_ATTR (_PAGE_PRESENT)
>
> -/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are
> - * used to save some data for jumping back
> +/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE
> + * ~ control_page + PAGE_SIZE * 3/4 are used to save some data for
> + * jumping back
> */
Hi Huang,
Above comment is not very clear. Can you please elaborate it. I thought
that PAGE_SIZE/2 is used for control code and rest half is shared between
kjump data and stack. What is PAGE_SIZE *3/4?
> -#define DATA(offset) (PAGE_SIZE/2+(offset))
> +#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset))
>
> /* Minimal CPU state */
> #define ESP DATA(0x0)
> @@ -376,3 +377,6 @@ swap_pages:
> popl %ebx
> popl %ebp
> ret
> +
> + .globl kexec_control_code_size
> +.set kexec_control_code_size, . - relocate_kernel
> --- a/include/asm-x86/kexec.h
> +++ b/include/asm-x86/kexec.h
> @@ -41,6 +41,10 @@
> # define PAGES_NR 17
> #endif
>
> +#ifdef CONFIG_X86_32
> +# define KEXEC_CONTROL_CODE_MAX_SIZE 2048
> +#endif
> +
> #ifndef __ASSEMBLY__
>
> #include <linux/string.h>
> --- a/arch/x86/kernel/vmlinux_32.lds.S
> +++ b/arch/x86/kernel/vmlinux_32.lds.S
> @@ -209,3 +209,5 @@ SECTIONS
>
> DWARF_DEBUG
> }
> +
> +#include "vmlinux_check_32.lds.S"
> --- /dev/null
> +++ b/arch/x86/kernel/vmlinux_check_32.lds.S
> @@ -0,0 +1,7 @@
> +/*
> + * Link time checks
> + */
> +
> +#include <asm/kexec.h>
> +
> +ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE, "kexec control code size is too big")
Will it make sense to move it into vmlinux_32.lds.S itself? Creating a separate
file for a single check seems superfluous.
Thanks
Vivek
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH -v2 3/8] kexec jump: check code size in control page
@ 2008-08-08 14:09 ` Vivek Goyal
0 siblings, 0 replies; 6+ messages in thread
From: Vivek Goyal @ 2008-08-08 14:09 UTC (permalink / raw)
To: Huang Ying
Cc: Eric W. Biederman, Pavel Machek, nigel, Rafael J. Wysocki,
Andrew Morton, mingo, Linus Torvalds, linux-kernel,
Kexec Mailing List
On Fri, Aug 08, 2008 at 02:52:36PM +0800, Huang Ying wrote:
> Kexec/Kexec-jump require code size in control page is less than
> PAGE_SIZE/2. This patch add link-time checking for this.
>
> ASSERT() of ld link script is used as the link-time checking
> mechanism.
>
> Signed-off-by: Huang Ying <ying.huang@intel.com>
>
> ---
> arch/x86/kernel/machine_kexec_32.c | 2 +-
> arch/x86/kernel/relocate_kernel_32.S | 10 +++++++---
> arch/x86/kernel/vmlinux_32.lds.S | 2 ++
> arch/x86/kernel/vmlinux_check_32.lds.S | 7 +++++++
> include/asm-x86/kexec.h | 4 ++++
> 5 files changed, 21 insertions(+), 4 deletions(-)
>
> --- a/arch/x86/kernel/machine_kexec_32.c
> +++ b/arch/x86/kernel/machine_kexec_32.c
> @@ -138,7 +138,7 @@ void machine_kexec(struct kimage *image)
> }
>
> control_page = page_address(image->control_code_page);
> - memcpy(control_page, relocate_kernel, PAGE_SIZE/2);
> + memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE);
>
> relocate_kernel_ptr = control_page;
> page_list[PA_CONTROL_PAGE] = __pa(control_page);
> --- a/arch/x86/kernel/relocate_kernel_32.S
> +++ b/arch/x86/kernel/relocate_kernel_32.S
> @@ -20,10 +20,11 @@
> #define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
> #define PAE_PGD_ATTR (_PAGE_PRESENT)
>
> -/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are
> - * used to save some data for jumping back
> +/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE
> + * ~ control_page + PAGE_SIZE * 3/4 are used to save some data for
> + * jumping back
> */
Hi Huang,
Above comment is not very clear. Can you please elaborate it. I thought
that PAGE_SIZE/2 is used for control code and rest half is shared between
kjump data and stack. What is PAGE_SIZE *3/4?
> -#define DATA(offset) (PAGE_SIZE/2+(offset))
> +#define DATA(offset) (KEXEC_CONTROL_CODE_MAX_SIZE+(offset))
>
> /* Minimal CPU state */
> #define ESP DATA(0x0)
> @@ -376,3 +377,6 @@ swap_pages:
> popl %ebx
> popl %ebp
> ret
> +
> + .globl kexec_control_code_size
> +.set kexec_control_code_size, . - relocate_kernel
> --- a/include/asm-x86/kexec.h
> +++ b/include/asm-x86/kexec.h
> @@ -41,6 +41,10 @@
> # define PAGES_NR 17
> #endif
>
> +#ifdef CONFIG_X86_32
> +# define KEXEC_CONTROL_CODE_MAX_SIZE 2048
> +#endif
> +
> #ifndef __ASSEMBLY__
>
> #include <linux/string.h>
> --- a/arch/x86/kernel/vmlinux_32.lds.S
> +++ b/arch/x86/kernel/vmlinux_32.lds.S
> @@ -209,3 +209,5 @@ SECTIONS
>
> DWARF_DEBUG
> }
> +
> +#include "vmlinux_check_32.lds.S"
> --- /dev/null
> +++ b/arch/x86/kernel/vmlinux_check_32.lds.S
> @@ -0,0 +1,7 @@
> +/*
> + * Link time checks
> + */
> +
> +#include <asm/kexec.h>
> +
> +ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE, "kexec control code size is too big")
Will it make sense to move it into vmlinux_32.lds.S itself? Creating a separate
file for a single check seems superfluous.
Thanks
Vivek
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH -v2 3/8] kexec jump: check code size in control page
2008-08-08 14:09 ` Vivek Goyal
@ 2008-08-11 1:02 ` Huang Ying
-1 siblings, 0 replies; 6+ messages in thread
From: Huang Ying @ 2008-08-11 1:02 UTC (permalink / raw)
To: Vivek Goyal
Cc: nigel, Kexec Mailing List, linux-kernel, Rafael J. Wysocki,
Eric W. Biederman, Pavel Machek, Andrew Morton, Linus Torvalds,
mingo
Hi, Vivek,
On Fri, 2008-08-08 at 10:09 -0400, Vivek Goyal wrote:
[...]
> > --- a/arch/x86/kernel/relocate_kernel_32.S
> > +++ b/arch/x86/kernel/relocate_kernel_32.S
> > @@ -20,10 +20,11 @@
> > #define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
> > #define PAE_PGD_ATTR (_PAGE_PRESENT)
> >
> > -/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are
> > - * used to save some data for jumping back
> > +/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE
> > + * ~ control_page + PAGE_SIZE * 3/4 are used to save some data for
> > + * jumping back
> > */
>
> Hi Huang,
>
> Above comment is not very clear. Can you please elaborate it. I thought
> that PAGE_SIZE/2 is used for control code and rest half is shared between
> kjump data and stack. What is PAGE_SIZE *3/4?
Yes. Rest half is shared between kjump data and stack. I will change it.
> > +++ b/arch/x86/kernel/vmlinux_check_32.lds.S
> > @@ -0,0 +1,7 @@
> > +/*
> > + * Link time checks
> > + */
> > +
> > +#include <asm/kexec.h>
> > +
> > +ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
> "kexec control code size is too big")
>
> Will it make sense to move it into vmlinux_32.lds.S itself? Creating a
> separate
> file for a single check seems superfluous.
I hope other ones can use it. But for now, put it in vmlinux_32.lds.S is
better. I will change it.
Best Regards,
HUang Ying
_______________________________________________
kexec mailing list
kexec@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/kexec
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH -v2 3/8] kexec jump: check code size in control page
@ 2008-08-11 1:02 ` Huang Ying
0 siblings, 0 replies; 6+ messages in thread
From: Huang Ying @ 2008-08-11 1:02 UTC (permalink / raw)
To: Vivek Goyal
Cc: Eric W. Biederman, Pavel Machek, nigel, Rafael J. Wysocki,
Andrew Morton, mingo, Linus Torvalds, linux-kernel,
Kexec Mailing List
Hi, Vivek,
On Fri, 2008-08-08 at 10:09 -0400, Vivek Goyal wrote:
[...]
> > --- a/arch/x86/kernel/relocate_kernel_32.S
> > +++ b/arch/x86/kernel/relocate_kernel_32.S
> > @@ -20,10 +20,11 @@
> > #define PAGE_ATTR (_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
> > #define PAE_PGD_ATTR (_PAGE_PRESENT)
> >
> > -/* control_page + PAGE_SIZE/2 ~ control_page + PAGE_SIZE * 3/4 are
> > - * used to save some data for jumping back
> > +/* control_page + KEXEC_CONTROL_CODE_MAX_SIZE
> > + * ~ control_page + PAGE_SIZE * 3/4 are used to save some data for
> > + * jumping back
> > */
>
> Hi Huang,
>
> Above comment is not very clear. Can you please elaborate it. I thought
> that PAGE_SIZE/2 is used for control code and rest half is shared between
> kjump data and stack. What is PAGE_SIZE *3/4?
Yes. Rest half is shared between kjump data and stack. I will change it.
> > +++ b/arch/x86/kernel/vmlinux_check_32.lds.S
> > @@ -0,0 +1,7 @@
> > +/*
> > + * Link time checks
> > + */
> > +
> > +#include <asm/kexec.h>
> > +
> > +ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
> "kexec control code size is too big")
>
> Will it make sense to move it into vmlinux_32.lds.S itself? Creating a
> separate
> file for a single check seems superfluous.
I hope other ones can use it. But for now, put it in vmlinux_32.lds.S is
better. I will change it.
Best Regards,
HUang Ying
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2008-08-11 1:02 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2008-08-08 6:52 [PATCH -v2 3/8] kexec jump: check code size in control page Huang Ying
2008-08-08 6:52 ` Huang Ying
2008-08-08 14:09 ` Vivek Goyal
2008-08-08 14:09 ` Vivek Goyal
2008-08-11 1:02 ` Huang Ying
2008-08-11 1:02 ` Huang Ying
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