diff mbox series

[kvm-unit-tests,1/5] s390x: Add a linker script to assembly snippets

Message ID 20221123084656.19864-2-frankja@linux.ibm.com (mailing list archive)
State New, archived
Headers show
Series s390x: Snippet fixes | expand

Commit Message

Janosch Frank Nov. 23, 2022, 8:46 a.m. UTC 
A linker script has a few benefits:
- Random data doesn't end up in the binary breaking tests
- We can easily define a lowcore and load the snippet from 0x0 instead
of 0x4000 which makes asm snippets behave like c snippets
- We can easily define an invalid PGM new PSW to ensure an exit on a
guest PGM

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 lib/s390x/snippet.h         |  3 +--
 s390x/Makefile              |  5 +++--
 s390x/mvpg-sie.c            |  2 +-
 s390x/pv-diags.c            |  6 +++---
 s390x/snippets/asm/flat.lds | 43 +++++++++++++++++++++++++++++++++++++
 5 files changed, 51 insertions(+), 8 deletions(-)
 create mode 100644 s390x/snippets/asm/flat.lds

Comments

Claudio Imbrenda Nov. 23, 2022, 12:45 p.m. UTC | #1 
On Wed, 23 Nov 2022 08:46:52 +0000
Janosch Frank <frankja@linux.ibm.com> wrote:

> A linker script has a few benefits:
> - Random data doesn't end up in the binary breaking tests
> - We can easily define a lowcore and load the snippet from 0x0 instead
> of 0x4000 which makes asm snippets behave like c snippets
> - We can easily define an invalid PGM new PSW to ensure an exit on a
> guest PGM
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>

looks good in general, but I have a few questions

> ---
>  lib/s390x/snippet.h         |  3 +--
>  s390x/Makefile              |  5 +++--
>  s390x/mvpg-sie.c            |  2 +-
>  s390x/pv-diags.c            |  6 +++---
>  s390x/snippets/asm/flat.lds | 43 +++++++++++++++++++++++++++++++++++++
>  5 files changed, 51 insertions(+), 8 deletions(-)
>  create mode 100644 s390x/snippets/asm/flat.lds
> 
> diff --git a/lib/s390x/snippet.h b/lib/s390x/snippet.h
> index b17b2a4c..57045994 100644
> --- a/lib/s390x/snippet.h
> +++ b/lib/s390x/snippet.h
> @@ -32,8 +32,7 @@
>  
>  #define SNIPPET_PV_TWEAK0	0x42UL
>  #define SNIPPET_PV_TWEAK1	0UL
> -#define SNIPPET_OFF_C		0
> -#define SNIPPET_OFF_ASM		0x4000
> +#define SNIPPET_UNPACK_OFF	0
>  
>  
>  /*
> diff --git a/s390x/Makefile b/s390x/Makefile
> index bf1504f9..bb0f9eb8 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -135,7 +135,8 @@ $(SNIPPET_DIR)/c/%.o: $(SNIPPET_DIR)/c/%.c $(asm-offsets)
>  	$(CC) $(CFLAGS) -c -nostdlib -o $@ $<
>  
>  $(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o
> -	$(OBJCOPY) -O binary -j ".rodata" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $(patsubst %.gbin,%.o,$@) $@
> +	$(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/snippets/asm/flat.lds $(patsubst %.gbin,%.o,$@)

I think you can simply use $< instead of the patsubst expression

> +	$(OBJCOPY) -O binary -j ".rodata" -j ".lowcore" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $@ $@
>  	truncate -s '%4096' $@
>  
>  $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
> @@ -144,7 +145,7 @@ $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
>  	truncate -s '%4096' $@
>  
>  $(SNIPPET_DIR)/asm/%.hdr: $(SNIPPET_DIR)/asm/%.gbin $(HOST_KEY_DOCUMENT)
> -	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x4000,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
> +	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
>  
>  $(SNIPPET_DIR)/c/%.hdr: $(SNIPPET_DIR)/c/%.gbin $(HOST_KEY_DOCUMENT)
>  	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
> diff --git a/s390x/mvpg-sie.c b/s390x/mvpg-sie.c
> index 46a2edb6..99f4859b 100644
> --- a/s390x/mvpg-sie.c
> +++ b/s390x/mvpg-sie.c
> @@ -87,7 +87,7 @@ static void setup_guest(void)
>  
>  	snippet_setup_guest(&vm, false);
>  	snippet_init(&vm, SNIPPET_NAME_START(c, mvpg_snippet),
> -		     SNIPPET_LEN(c, mvpg_snippet), SNIPPET_OFF_C);
> +		     SNIPPET_LEN(c, mvpg_snippet), SNIPPET_UNPACK_OFF);
>  
>  	/* Enable MVPG interpretation as we want to test KVM and not ourselves */
>  	vm.sblk->eca = ECA_MVPGI;
> diff --git a/s390x/pv-diags.c b/s390x/pv-diags.c
> index 9ced68c7..5165937a 100644
> --- a/s390x/pv-diags.c
> +++ b/s390x/pv-diags.c
> @@ -28,7 +28,7 @@ static void test_diag_500(void)
>  
>  	snippet_pv_init(&vm, SNIPPET_NAME_START(asm, snippet_pv_diag_500),
>  			SNIPPET_HDR_START(asm, snippet_pv_diag_500),
> -			size_gbin, size_hdr, SNIPPET_OFF_ASM);
> +			size_gbin, size_hdr, SNIPPET_UNPACK_OFF);
>  
>  	sie(&vm);
>  	report(vm.sblk->icptcode == ICPT_PV_INSTR && vm.sblk->ipa == 0x8302 &&
> @@ -83,7 +83,7 @@ static void test_diag_288(void)
>  
>  	snippet_pv_init(&vm, SNIPPET_NAME_START(asm, snippet_pv_diag_288),
>  			SNIPPET_HDR_START(asm, snippet_pv_diag_288),
> -			size_gbin, size_hdr, SNIPPET_OFF_ASM);
> +			size_gbin, size_hdr, SNIPPET_UNPACK_OFF);
>  
>  	sie(&vm);
>  	report(vm.sblk->icptcode == ICPT_PV_INSTR && vm.sblk->ipa == 0x8302 &&
> @@ -124,7 +124,7 @@ static void test_diag_yield(void)
>  
>  	snippet_pv_init(&vm, SNIPPET_NAME_START(asm, snippet_pv_diag_yield),
>  			SNIPPET_HDR_START(asm, snippet_pv_diag_yield),
> -			size_gbin, size_hdr, SNIPPET_OFF_ASM);
> +			size_gbin, size_hdr, SNIPPET_UNPACK_OFF);
>  
>  	/* 0x44 */
>  	report_prefix_push("0x44");
> diff --git a/s390x/snippets/asm/flat.lds b/s390x/snippets/asm/flat.lds
> new file mode 100644
> index 00000000..366d2d78
> --- /dev/null
> +++ b/s390x/snippets/asm/flat.lds
> @@ -0,0 +1,43 @@
> +SECTIONS
> +{
> +	.lowcore : {
> +		/*
> +		 * Initial short psw for disk boot, with 31 bit addressing for
> +		 * non z/Arch environment compatibility and the instruction
> +		 * address 0x4000.
> +		 */
> +		. = 0;
> +		 LONG(0x00080000)
> +		 LONG(0x80004000)
> +		 /* Restart new PSW for booting via PSW restart. */
> +		 . = 0x1a0;
> +		 QUAD(0x0000000180000000)
> +		 QUAD(0x0000000000004000)
> +		 /*
> +		  * Invalid PGM new PSW so we hopefully get a code 8
> +		  * intercept on a PGM
> +		  */
> +		 . = 0x1d0;
> +		 QUAD(0x0008000000000000)
> +		 QUAD(0x0000000000000001)
> +	}
> +	. = 0x4000;
> +	.text : {
> +		*(.text)
> +		*(.text.*)
> +	}
> +	. = ALIGN(64K);

any reason to align to 64k? (instead of e.g. 4k)

> +	etext = .;
> +	. = ALIGN(16);

do you need the ALIGN? I would think we are already aligned here

> +	.data : {
> +		*(.data)
> +		*(.data.rel*)
> +	}
> +	. = ALIGN(16);
> +	.rodata : { *(.rodata) *(.rodata.*) }
> +	. = ALIGN(16);
> +	__bss_start = .;
> +	.bss : { *(.bss) }
> +	__bss_end = .;
> +	. = ALIGN(64K);

same question as above regarding 64k

> +}
Janosch Frank Nov. 24, 2022, 2:28 p.m. UTC | #2 
On 11/23/22 13:45, Claudio Imbrenda wrote:
> On Wed, 23 Nov 2022 08:46:52 +0000
> Janosch Frank <frankja@linux.ibm.com> wrote:
> 
>> A linker script has a few benefits:
>> - Random data doesn't end up in the binary breaking tests
>> - We can easily define a lowcore and load the snippet from 0x0 instead
>> of 0x4000 which makes asm snippets behave like c snippets
>> - We can easily define an invalid PGM new PSW to ensure an exit on a
>> guest PGM
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> 
> looks good in general, but I have a few questions
> 
>> ---
>>   lib/s390x/snippet.h         |  3 +--
>>   s390x/Makefile              |  5 +++--
>>   s390x/mvpg-sie.c            |  2 +-
>>   s390x/pv-diags.c            |  6 +++---
>>   s390x/snippets/asm/flat.lds | 43 +++++++++++++++++++++++++++++++++++++
>>   5 files changed, 51 insertions(+), 8 deletions(-)
>>   create mode 100644 s390x/snippets/asm/flat.lds
>>
>> diff --git a/lib/s390x/snippet.h b/lib/s390x/snippet.h
>> index b17b2a4c..57045994 100644
>> --- a/lib/s390x/snippet.h
>> +++ b/lib/s390x/snippet.h
>> @@ -32,8 +32,7 @@
>>   
>>   #define SNIPPET_PV_TWEAK0	0x42UL
>>   #define SNIPPET_PV_TWEAK1	0UL
>> -#define SNIPPET_OFF_C		0
>> -#define SNIPPET_OFF_ASM		0x4000
>> +#define SNIPPET_UNPACK_OFF	0
>>   
>>   
>>   /*
>> diff --git a/s390x/Makefile b/s390x/Makefile
>> index bf1504f9..bb0f9eb8 100644
>> --- a/s390x/Makefile
>> +++ b/s390x/Makefile
>> @@ -135,7 +135,8 @@ $(SNIPPET_DIR)/c/%.o: $(SNIPPET_DIR)/c/%.c $(asm-offsets)
>>   	$(CC) $(CFLAGS) -c -nostdlib -o $@ $<
>>   
>>   $(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o
>> -	$(OBJCOPY) -O binary -j ".rodata" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $(patsubst %.gbin,%.o,$@) $@
>> +	$(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/snippets/asm/flat.lds $(patsubst %.gbin,%.o,$@)
> 
> I think you can simply use $< instead of the patsubst expression

Right, I'll fix that momentarily.

[...]

>> +	.text : {
>> +		*(.text)
>> +		*(.text.*)
>> +	}
>> +	. = ALIGN(64K);
> 
> any reason to align to 64k? (instead of e.g. 4k)

Well, I've copied that from s390x/flat.lds...
I'll have a look at the required alignments when I find time.

> 
>> +	etext = .;
>> +	. = ALIGN(16);
> 
> do you need the ALIGN? I would think we are already aligned here
> 
>> +	.data : {
>> +		*(.data)
>> +		*(.data.rel*)
>> +	}
>> +	. = ALIGN(16);
>> +	.rodata : { *(.rodata) *(.rodata.*) }
>> +	. = ALIGN(16);
>> +	__bss_start = .;
>> +	.bss : { *(.bss) }
>> +	__bss_end = .;
>> +	. = ALIGN(64K);
> 
> same question as above regarding 64k
> 
>> +}
>
Janis Schoetterl-Glausch Nov. 24, 2022, 8:42 p.m. UTC | #3 
On Wed, 2022-11-23 at 08:46 +0000, Janosch Frank wrote:
> A linker script has a few benefits:
> - Random data doesn't end up in the binary breaking tests
> - We can easily define a lowcore and load the snippet from 0x0 instead
> of 0x4000 which makes asm snippets behave like c snippets
> - We can easily define an invalid PGM new PSW to ensure an exit on a
> guest PGM
> 
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> ---
>  lib/s390x/snippet.h         |  3 +--
>  s390x/Makefile              |  5 +++--
>  s390x/mvpg-sie.c            |  2 +-
>  s390x/pv-diags.c            |  6 +++---
>  s390x/snippets/asm/flat.lds | 43 +++++++++++++++++++++++++++++++++++++
>  5 files changed, 51 insertions(+), 8 deletions(-)
>  create mode 100644 s390x/snippets/asm/flat.lds
> 
> diff --git a/lib/s390x/snippet.h b/lib/s390x/snippet.h
> index b17b2a4c..57045994 100644
> --- a/lib/s390x/snippet.h
> +++ b/lib/s390x/snippet.h
> @@ -32,8 +32,7 @@
> 
>  #define SNIPPET_PV_TWEAK0	0x42UL
>  #define SNIPPET_PV_TWEAK1	0UL
> -#define SNIPPET_OFF_C		0
> -#define SNIPPET_OFF_ASM		0x4000
> +#define SNIPPET_UNPACK_OFF	0

You could also get rid of the offset parameter, couldn't you?
> 
> 
>  /*
> diff --git a/s390x/Makefile b/s390x/Makefile
> index bf1504f9..bb0f9eb8 100644
> --- a/s390x/Makefile
> +++ b/s390x/Makefile
> @@ -135,7 +135,8 @@ $(SNIPPET_DIR)/c/%.o: $(SNIPPET_DIR)/c/%.c $(asm-offsets)
>  	$(CC) $(CFLAGS) -c -nostdlib -o $@ $<
> 
>  $(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o
> -	$(OBJCOPY) -O binary -j ".rodata" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $(patsubst %.gbin,%.o,$@) $@
> +	$(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/snippets/asm/flat.lds $(patsubst %.gbin,%.o,$@)
> +	$(OBJCOPY) -O binary -j ".rodata" -j ".lowcore" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $@ $@

I assume .bss=alloc allocates the bss in the binary...

>  	truncate -s '%4096' $@
> 
>  $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
> @@ -144,7 +145,7 @@ $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
>  	truncate -s '%4096' $@
> 
>  $(SNIPPET_DIR)/asm/%.hdr: $(SNIPPET_DIR)/asm/%.gbin $(HOST_KEY_DOCUMENT)
> -	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x4000,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
> +	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
> 
>  $(SNIPPET_DIR)/c/%.hdr: $(SNIPPET_DIR)/c/%.gbin $(HOST_KEY_DOCUMENT)
>  	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
> 
[...]

> diff --git a/s390x/snippets/asm/flat.lds b/s390x/snippets/asm/flat.lds
> new file mode 100644
> index 00000000..366d2d78
> --- /dev/null
> +++ b/s390x/snippets/asm/flat.lds
> @@ -0,0 +1,43 @@
> +SECTIONS
> +{
> +	.lowcore : {
> +		/*
> +		 * Initial short psw for disk boot, with 31 bit addressing for
> +		 * non z/Arch environment compatibility and the instruction
> +		 * address 0x4000.
> +		 */
> +		. = 0;
> +		 LONG(0x00080000)
> +		 LONG(0x80004000)
> +		 /* Restart new PSW for booting via PSW restart. */
> +		 . = 0x1a0;
> +		 QUAD(0x0000000180000000)
> +		 QUAD(0x0000000000004000)
> +		 /*
> +		  * Invalid PGM new PSW so we hopefully get a code 8
> +		  * intercept on a PGM
> +		  */
> +		 . = 0x1d0;
> +		 QUAD(0x0008000000000000)
> +		 QUAD(0x0000000000000001)
> +	}
> +	. = 0x4000;
> +	.text : {
> +		*(.text)
> +		*(.text.*)
> +	}
> +	. = ALIGN(64K);
> +	etext = .;
> +	. = ALIGN(16);
> +	.data : {
> +		*(.data)
> +		*(.data.rel*)
> +	}
> +	. = ALIGN(16);
> +	.rodata : { *(.rodata) *(.rodata.*) }
> +	. = ALIGN(16);
> +	__bss_start = .;

.. so the __bss symbols are not necessary.
But then, the c flat.lds has them too.
> +	.bss : { *(.bss) }
> +	__bss_end = .;
> +	. = ALIGN(64K);
> +}
Janosch Frank Nov. 25, 2022, 10:07 a.m. UTC | #4 
On 11/24/22 21:42, Janis Schoetterl-Glausch wrote:
> On Wed, 2022-11-23 at 08:46 +0000, Janosch Frank wrote:
>> A linker script has a few benefits:
>> - Random data doesn't end up in the binary breaking tests
>> - We can easily define a lowcore and load the snippet from 0x0 instead
>> of 0x4000 which makes asm snippets behave like c snippets
>> - We can easily define an invalid PGM new PSW to ensure an exit on a
>> guest PGM
>>
>> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
>> ---
>>   lib/s390x/snippet.h         |  3 +--
>>   s390x/Makefile              |  5 +++--
>>   s390x/mvpg-sie.c            |  2 +-
>>   s390x/pv-diags.c            |  6 +++---
>>   s390x/snippets/asm/flat.lds | 43 +++++++++++++++++++++++++++++++++++++
>>   5 files changed, 51 insertions(+), 8 deletions(-)
>>   create mode 100644 s390x/snippets/asm/flat.lds
>>
>> diff --git a/lib/s390x/snippet.h b/lib/s390x/snippet.h
>> index b17b2a4c..57045994 100644
>> --- a/lib/s390x/snippet.h
>> +++ b/lib/s390x/snippet.h
>> @@ -32,8 +32,7 @@
>>
>>   #define SNIPPET_PV_TWEAK0	0x42UL
>>   #define SNIPPET_PV_TWEAK1	0UL
>> -#define SNIPPET_OFF_C		0
>> -#define SNIPPET_OFF_ASM		0x4000
>> +#define SNIPPET_UNPACK_OFF	0
> 
> You could also get rid of the offset parameter, couldn't you?

Right

>>
>>
>>   /*
>> diff --git a/s390x/Makefile b/s390x/Makefile
>> index bf1504f9..bb0f9eb8 100644
>> --- a/s390x/Makefile
>> +++ b/s390x/Makefile
>> @@ -135,7 +135,8 @@ $(SNIPPET_DIR)/c/%.o: $(SNIPPET_DIR)/c/%.c $(asm-offsets)
>>   	$(CC) $(CFLAGS) -c -nostdlib -o $@ $<
>>
>>   $(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o
>> -	$(OBJCOPY) -O binary -j ".rodata" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $(patsubst %.gbin,%.o,$@) $@
>> +	$(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/snippets/asm/flat.lds $(patsubst %.gbin,%.o,$@)
>> +	$(OBJCOPY) -O binary -j ".rodata" -j ".lowcore" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $@ $@
> 
> I assume .bss=alloc allocates the bss in the binary...

And that's fine since I don't want to handle 0x3E PGMs/faults.

If bss is in the binary then it'll be made secure on initial image 
unpack, if it isn't, then we need a handler to import pages on a 0x3E. 
And I don't really want to do that since a 0x3E could also mean that we 
have an issue with the test or HW/FW.

> 
>>   	truncate -s '%4096' $@
>>
>>   $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
>> @@ -144,7 +145,7 @@ $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
>>   	truncate -s '%4096' $@
>>
>>   $(SNIPPET_DIR)/asm/%.hdr: $(SNIPPET_DIR)/asm/%.gbin $(HOST_KEY_DOCUMENT)
>> -	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x4000,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
>> +	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
>>
>>   $(SNIPPET_DIR)/c/%.hdr: $(SNIPPET_DIR)/c/%.gbin $(HOST_KEY_DOCUMENT)
>>   	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
>>
> [...]
> 
>> diff --git a/s390x/snippets/asm/flat.lds b/s390x/snippets/asm/flat.lds
>> new file mode 100644
>> index 00000000..366d2d78
>> --- /dev/null
>> +++ b/s390x/snippets/asm/flat.lds
>> @@ -0,0 +1,43 @@
>> +SECTIONS
>> +{
>> +	.lowcore : {
>> +		/*
>> +		 * Initial short psw for disk boot, with 31 bit addressing for
>> +		 * non z/Arch environment compatibility and the instruction
>> +		 * address 0x4000.
>> +		 */
>> +		. = 0;
>> +		 LONG(0x00080000)
>> +		 LONG(0x80004000)
>> +		 /* Restart new PSW for booting via PSW restart. */
>> +		 . = 0x1a0;
>> +		 QUAD(0x0000000180000000)
>> +		 QUAD(0x0000000000004000)
>> +		 /*
>> +		  * Invalid PGM new PSW so we hopefully get a code 8
>> +		  * intercept on a PGM
>> +		  */
>> +		 . = 0x1d0;
>> +		 QUAD(0x0008000000000000)
>> +		 QUAD(0x0000000000000001)
>> +	}
>> +	. = 0x4000;
>> +	.text : {
>> +		*(.text)
>> +		*(.text.*)
>> +	}
>> +	. = ALIGN(64K);
>> +	etext = .;
>> +	. = ALIGN(16);
>> +	.data : {
>> +		*(.data)
>> +		*(.data.rel*)
>> +	}
>> +	. = ALIGN(16);
>> +	.rodata : { *(.rodata) *(.rodata.*) }
>> +	. = ALIGN(16);
>> +	__bss_start = .;
> 
> .. so the __bss symbols are not necessary.
> But then, the c flat.lds has them too.
>> +	.bss : { *(.bss) }
>> +	__bss_end = .;
>> +	. = ALIGN(64K);
>> +}
>
diff mbox series

Patch

diff --git a/lib/s390x/snippet.h b/lib/s390x/snippet.h
index b17b2a4c..57045994 100644
--- a/lib/s390x/snippet.h
+++ b/lib/s390x/snippet.h
@@ -32,8 +32,7 @@ 
 
 #define SNIPPET_PV_TWEAK0	0x42UL
 #define SNIPPET_PV_TWEAK1	0UL
-#define SNIPPET_OFF_C		0
-#define SNIPPET_OFF_ASM		0x4000
+#define SNIPPET_UNPACK_OFF	0
 
 
 /*
diff --git a/s390x/Makefile b/s390x/Makefile
index bf1504f9..bb0f9eb8 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -135,7 +135,8 @@  $(SNIPPET_DIR)/c/%.o: $(SNIPPET_DIR)/c/%.c $(asm-offsets)
 	$(CC) $(CFLAGS) -c -nostdlib -o $@ $<
 
 $(SNIPPET_DIR)/asm/%.gbin: $(SNIPPET_DIR)/asm/%.o
-	$(OBJCOPY) -O binary -j ".rodata" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $(patsubst %.gbin,%.o,$@) $@
+	$(CC) $(LDFLAGS) -o $@ -T $(SRCDIR)/s390x/snippets/asm/flat.lds $(patsubst %.gbin,%.o,$@)
+	$(OBJCOPY) -O binary -j ".rodata" -j ".lowcore" -j ".text" -j ".data" -j ".bss" --set-section-flags .bss=alloc,load,contents $@ $@
 	truncate -s '%4096' $@
 
 $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
@@ -144,7 +145,7 @@  $(SNIPPET_DIR)/c/%.gbin: $(SNIPPET_DIR)/c/%.o $(snippet_lib) $(FLATLIBS)
 	truncate -s '%4096' $@
 
 $(SNIPPET_DIR)/asm/%.hdr: $(SNIPPET_DIR)/asm/%.gbin $(HOST_KEY_DOCUMENT)
-	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x4000,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
+	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
 
 $(SNIPPET_DIR)/c/%.hdr: $(SNIPPET_DIR)/c/%.gbin $(HOST_KEY_DOCUMENT)
 	$(GEN_SE_HEADER) -k $(HOST_KEY_DOCUMENT) -c $<,0x0,0x00000000000000420000000000000000 --psw-addr 0x4000 -o $@
diff --git a/s390x/mvpg-sie.c b/s390x/mvpg-sie.c
index 46a2edb6..99f4859b 100644
--- a/s390x/mvpg-sie.c
+++ b/s390x/mvpg-sie.c
@@ -87,7 +87,7 @@  static void setup_guest(void)
 
 	snippet_setup_guest(&vm, false);
 	snippet_init(&vm, SNIPPET_NAME_START(c, mvpg_snippet),
-		     SNIPPET_LEN(c, mvpg_snippet), SNIPPET_OFF_C);
+		     SNIPPET_LEN(c, mvpg_snippet), SNIPPET_UNPACK_OFF);
 
 	/* Enable MVPG interpretation as we want to test KVM and not ourselves */
 	vm.sblk->eca = ECA_MVPGI;
diff --git a/s390x/pv-diags.c b/s390x/pv-diags.c
index 9ced68c7..5165937a 100644
--- a/s390x/pv-diags.c
+++ b/s390x/pv-diags.c
@@ -28,7 +28,7 @@  static void test_diag_500(void)
 
 	snippet_pv_init(&vm, SNIPPET_NAME_START(asm, snippet_pv_diag_500),
 			SNIPPET_HDR_START(asm, snippet_pv_diag_500),
-			size_gbin, size_hdr, SNIPPET_OFF_ASM);
+			size_gbin, size_hdr, SNIPPET_UNPACK_OFF);
 
 	sie(&vm);
 	report(vm.sblk->icptcode == ICPT_PV_INSTR && vm.sblk->ipa == 0x8302 &&
@@ -83,7 +83,7 @@  static void test_diag_288(void)
 
 	snippet_pv_init(&vm, SNIPPET_NAME_START(asm, snippet_pv_diag_288),
 			SNIPPET_HDR_START(asm, snippet_pv_diag_288),
-			size_gbin, size_hdr, SNIPPET_OFF_ASM);
+			size_gbin, size_hdr, SNIPPET_UNPACK_OFF);
 
 	sie(&vm);
 	report(vm.sblk->icptcode == ICPT_PV_INSTR && vm.sblk->ipa == 0x8302 &&
@@ -124,7 +124,7 @@  static void test_diag_yield(void)
 
 	snippet_pv_init(&vm, SNIPPET_NAME_START(asm, snippet_pv_diag_yield),
 			SNIPPET_HDR_START(asm, snippet_pv_diag_yield),
-			size_gbin, size_hdr, SNIPPET_OFF_ASM);
+			size_gbin, size_hdr, SNIPPET_UNPACK_OFF);
 
 	/* 0x44 */
 	report_prefix_push("0x44");
diff --git a/s390x/snippets/asm/flat.lds b/s390x/snippets/asm/flat.lds
new file mode 100644
index 00000000..366d2d78
--- /dev/null
+++ b/s390x/snippets/asm/flat.lds
@@ -0,0 +1,43 @@ 
+SECTIONS
+{
+	.lowcore : {
+		/*
+		 * Initial short psw for disk boot, with 31 bit addressing for
+		 * non z/Arch environment compatibility and the instruction
+		 * address 0x4000.
+		 */
+		. = 0;
+		 LONG(0x00080000)
+		 LONG(0x80004000)
+		 /* Restart new PSW for booting via PSW restart. */
+		 . = 0x1a0;
+		 QUAD(0x0000000180000000)
+		 QUAD(0x0000000000004000)
+		 /*
+		  * Invalid PGM new PSW so we hopefully get a code 8
+		  * intercept on a PGM
+		  */
+		 . = 0x1d0;
+		 QUAD(0x0008000000000000)
+		 QUAD(0x0000000000000001)
+	}
+	. = 0x4000;
+	.text : {
+		*(.text)
+		*(.text.*)
+	}
+	. = ALIGN(64K);
+	etext = .;
+	. = ALIGN(16);
+	.data : {
+		*(.data)
+		*(.data.rel*)
+	}
+	. = ALIGN(16);
+	.rodata : { *(.rodata) *(.rodata.*) }
+	. = ALIGN(16);
+	__bss_start = .;
+	.bss : { *(.bss) }
+	__bss_end = .;
+	. = ALIGN(64K);
+}