After reactivation of data translation by modifying MSR[DR], a isync
is required to ensure the translation is effective.
Signed-off-by: Christophe Leroy <[email protected]>
---
Rebased on powerpc/merge-test
@mpe: If not too late:
- change to head_32.h should be squashed into "powerpc/32: prepare for CONFIG_VMAP_STACK"
- change to head_32.S should be squashed into "powerpc/32s: Enable CONFIG_VMAP_STACK"
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/kernel/head_32.S | 1 +
arch/powerpc/kernel/head_32.h | 2 ++
2 files changed, 3 insertions(+)
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
index cb7864091641..0493fcac6409 100644
--- a/arch/powerpc/kernel/head_32.S
+++ b/arch/powerpc/kernel/head_32.S
@@ -277,6 +277,7 @@ MachineCheck:
#ifdef CONFIG_VMAP_STACK
li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
mtmsr r11
+ isync
#endif
#ifdef CONFIG_PPC_CHRP
mfspr r11, SPRN_SPRG_THREAD
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 73a035b40dbf..a6a5fbbf8504 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -43,6 +43,7 @@
.ifeq \for_rtas
li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
mtmsr r11
+ isync
.endif
subi r11, r1, INT_FRAME_SIZE /* use r1 if kernel */
#else
@@ -123,6 +124,7 @@
#ifdef CONFIG_VMAP_STACK
li r9, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
mtmsr r9
+ isync
#endif
tovirt_vmstack r12, r12
tophys_novmstack r11, r11
--
2.25.0
Christophe Leroy <[email protected]> writes:
> After reactivation of data translation by modifying MSR[DR], a isync
> is required to ensure the translation is effective.
>
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> Rebased on powerpc/merge-test
>
> @mpe: If not too late:
> - change to head_32.h should be squashed into "powerpc/32: prepare for CONFIG_VMAP_STACK"
> - change to head_32.S should be squashed into "powerpc/32s: Enable CONFIG_VMAP_STACK"
Done. Thanks.
cheers
Christophe Leroy <[email protected]> writes:
> After reactivation of data translation by modifying MSR[DR], a isync
> is required to ensure the translation is effective.
>
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> Rebased on powerpc/merge-test
>
> @mpe: If not too late:
> - change to head_32.h should be squashed into "powerpc/32: prepare for CONFIG_VMAP_STACK"
> - change to head_32.S should be squashed into "powerpc/32s: Enable CONFIG_VMAP_STACK"
>
> Signed-off-by: Christophe Leroy <[email protected]>
> ---
> arch/powerpc/kernel/head_32.S | 1 +
> arch/powerpc/kernel/head_32.h | 2 ++
> 2 files changed, 3 insertions(+)
>
> diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
> index 73a035b40dbf..a6a5fbbf8504 100644
> --- a/arch/powerpc/kernel/head_32.h
> +++ b/arch/powerpc/kernel/head_32.h
> @@ -43,6 +43,7 @@
> .ifeq \for_rtas
> li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
> mtmsr r11
> + isync
Actually this one leads to:
/home/michael/linux/arch/powerpc/kernel/head_8xx.S: Assembler messages:
/home/michael/linux/arch/powerpc/kernel/head_8xx.S:151: Error: attempt to move .org backwards
make[3]: *** [/home/michael/linux/scripts/Makefile.build:348: arch/powerpc/kernel/head_8xx.o] Error 1
For mpc885_ads_defconfig.
That's the alignment exception overflowing into the program check
handler:
/* Alignment exception */
. = 0x600
Alignment:
EXCEPTION_PROLOG handle_dar_dsisr=1
save_dar_dsisr_on_stack r4, r5, r11
li r6, RPN_PATTERN
mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0x600, alignment_exception)
/* Program check exception */
EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
Can't see an obvious/easy way to fix it.
cheers
> .endif
> subi r11, r1, INT_FRAME_SIZE /* use r1 if kernel */
> #else
Michael Ellerman <[email protected]> a écrit :
> Christophe Leroy <[email protected]> writes:
>> After reactivation of data translation by modifying MSR[DR], a isync
>> is required to ensure the translation is effective.
>>
>> Signed-off-by: Christophe Leroy <[email protected]>
>> ---
>> Rebased on powerpc/merge-test
>>
>> @mpe: If not too late:
>> - change to head_32.h should be squashed into "powerpc/32: prepare
>> for CONFIG_VMAP_STACK"
>> - change to head_32.S should be squashed into "powerpc/32s: Enable
>> CONFIG_VMAP_STACK"
>>
>> Signed-off-by: Christophe Leroy <[email protected]>
>> ---
>> arch/powerpc/kernel/head_32.S | 1 +
>> arch/powerpc/kernel/head_32.h | 2 ++
>> 2 files changed, 3 insertions(+)
>>
>> diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
>> index 73a035b40dbf..a6a5fbbf8504 100644
>> --- a/arch/powerpc/kernel/head_32.h
>> +++ b/arch/powerpc/kernel/head_32.h
>> @@ -43,6 +43,7 @@
>> .ifeq \for_rtas
>> li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
>> mtmsr r11
>> + isync
>
> Actually this one leads to:
>
> /home/michael/linux/arch/powerpc/kernel/head_8xx.S: Assembler messages:
> /home/michael/linux/arch/powerpc/kernel/head_8xx.S:151: Error:
> attempt to move .org backwards
> make[3]: *** [/home/michael/linux/scripts/Makefile.build:348:
> arch/powerpc/kernel/head_8xx.o] Error 1
>
> For mpc885_ads_defconfig.
>
> That's the alignment exception overflowing into the program check
> handler:
>
> /* Alignment exception */
> . = 0x600
> Alignment:
> EXCEPTION_PROLOG handle_dar_dsisr=1
> save_dar_dsisr_on_stack r4, r5, r11
> li r6, RPN_PATTERN
> mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
> addi r3,r1,STACK_FRAME_OVERHEAD
> EXC_XFER_STD(0x600, alignment_exception)
>
> /* Program check exception */
> EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
>
>
> Can't see an obvious/easy way to fix it.
Argh !
I think the easiest is to move the EXC_XFER_STD(0x600,
alignment_exception) somewhere else and branch to it. There is some
space at .0xa00
Christophe
PS: I'm afk until monday
Christophe Leroy <[email protected]> writes:
> Michael Ellerman <[email protected]> a écrit :
>> Christophe Leroy <[email protected]> writes:
...
>>> diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
>>> index 73a035b40dbf..a6a5fbbf8504 100644
>>> --- a/arch/powerpc/kernel/head_32.h
>>> +++ b/arch/powerpc/kernel/head_32.h
>>> @@ -43,6 +43,7 @@
>>> .ifeq \for_rtas
>>> li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
>>> mtmsr r11
>>> + isync
>>
>> Actually this one leads to:
>>
>> /home/michael/linux/arch/powerpc/kernel/head_8xx.S: Assembler messages:
>> /home/michael/linux/arch/powerpc/kernel/head_8xx.S:151: Error:
>> attempt to move .org backwards
>> make[3]: *** [/home/michael/linux/scripts/Makefile.build:348:
>> arch/powerpc/kernel/head_8xx.o] Error 1
>>
>> For mpc885_ads_defconfig.
>>
>> That's the alignment exception overflowing into the program check
>> handler:
>>
>> /* Alignment exception */
>> . = 0x600
>> Alignment:
>> EXCEPTION_PROLOG handle_dar_dsisr=1
>> save_dar_dsisr_on_stack r4, r5, r11
>> li r6, RPN_PATTERN
>> mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
>> addi r3,r1,STACK_FRAME_OVERHEAD
>> EXC_XFER_STD(0x600, alignment_exception)
>>
>> /* Program check exception */
>> EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
>>
>>
>> Can't see an obvious/easy way to fix it.
>
> Argh !
>
> I think the easiest is to move the EXC_XFER_STD(0x600,
> alignment_exception) somewhere else and branch to it. There is some
> space at .0xa00
That works, or builds at least. I'm not setup to boot test it.
Does this look OK?
cheers
From 40e7d671aa27cf4411188f978b2cd06b30a9cb6c Mon Sep 17 00:00:00 2001
From: Michael Ellerman <[email protected]>
Date: Sun, 26 Jan 2020 00:20:16 +1100
Subject: [PATCH] powerpc/8xx: Move tail of alignment exception out of line
When we enable VMAP_STACK there will not be enough room for the
alignment handler at 0x600 in head_8xx.S. For now move the tail of the
alignment handler out of line, and branch to it.
Suggested-by: Christophe Leroy <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
---
arch/powerpc/kernel/head_8xx.S | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 477933b36bde..9922306ae512 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -145,7 +145,7 @@ _ENTRY(_start);
li r6, RPN_PATTERN
mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
addi r3,r1,STACK_FRAME_OVERHEAD
- EXC_XFER_STD(0x600, alignment_exception)
+ b .Lalignment_exception_ool
/* Program check exception */
EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
@@ -153,6 +153,11 @@ _ENTRY(_start);
/* Decrementer */
EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE)
+ /* With VMAP_STACK there's not enough room for this at 0x600 */
+ . = 0xa00
+.Lalignment_exception_ool:
+ EXC_XFER_STD(0x600, alignment_exception)
+
/* System call */
. = 0xc00
SystemCall:
--
2.21.1
Michael Ellerman <[email protected]> a écrit :
> Christophe Leroy <[email protected]> writes:
>> Michael Ellerman <[email protected]> a écrit :
>>> Christophe Leroy <[email protected]> writes:
> ...
>>>> diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
>>>> index 73a035b40dbf..a6a5fbbf8504 100644
>>>> --- a/arch/powerpc/kernel/head_32.h
>>>> +++ b/arch/powerpc/kernel/head_32.h
>>>> @@ -43,6 +43,7 @@
>>>> .ifeq \for_rtas
>>>> li r11, MSR_KERNEL & ~(MSR_IR | MSR_RI) /* can take DTLB miss */
>>>> mtmsr r11
>>>> + isync
>>>
>>> Actually this one leads to:
>>>
>>> /home/michael/linux/arch/powerpc/kernel/head_8xx.S: Assembler messages:
>>> /home/michael/linux/arch/powerpc/kernel/head_8xx.S:151: Error:
>>> attempt to move .org backwards
>>> make[3]: *** [/home/michael/linux/scripts/Makefile.build:348:
>>> arch/powerpc/kernel/head_8xx.o] Error 1
>>>
>>> For mpc885_ads_defconfig.
>>>
>>> That's the alignment exception overflowing into the program check
>>> handler:
>>>
>>> /* Alignment exception */
>>> . = 0x600
>>> Alignment:
>>> EXCEPTION_PROLOG handle_dar_dsisr=1
>>> save_dar_dsisr_on_stack r4, r5, r11
>>> li r6, RPN_PATTERN
>>> mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
>>> addi r3,r1,STACK_FRAME_OVERHEAD
>>> EXC_XFER_STD(0x600, alignment_exception)
>>>
>>> /* Program check exception */
>>> EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
>>>
>>>
>>> Can't see an obvious/easy way to fix it.
>>
>> Argh !
>>
>> I think the easiest is to move the EXC_XFER_STD(0x600,
>> alignment_exception) somewhere else and branch to it. There is some
>> space at .0xa00
>
> That works, or builds at least. I'm not setup to boot test it.
>
> Does this look OK?
Yes it looks ok,
Thanks
Christophe
>
> cheers
>
>
> From 40e7d671aa27cf4411188f978b2cd06b30a9cb6c Mon Sep 17 00:00:00 2001
> From: Michael Ellerman <[email protected]>
> Date: Sun, 26 Jan 2020 00:20:16 +1100
> Subject: [PATCH] powerpc/8xx: Move tail of alignment exception out of line
>
> When we enable VMAP_STACK there will not be enough room for the
> alignment handler at 0x600 in head_8xx.S. For now move the tail of the
> alignment handler out of line, and branch to it.
>
> Suggested-by: Christophe Leroy <[email protected]>
> Signed-off-by: Michael Ellerman <[email protected]>
> ---
> arch/powerpc/kernel/head_8xx.S | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
> index 477933b36bde..9922306ae512 100644
> --- a/arch/powerpc/kernel/head_8xx.S
> +++ b/arch/powerpc/kernel/head_8xx.S
> @@ -145,7 +145,7 @@ _ENTRY(_start);
> li r6, RPN_PATTERN
> mtspr SPRN_DAR, r6 /* Tag DAR, to be used in DTLB Error */
> addi r3,r1,STACK_FRAME_OVERHEAD
> - EXC_XFER_STD(0x600, alignment_exception)
> + b .Lalignment_exception_ool
>
> /* Program check exception */
> EXCEPTION(0x700, ProgramCheck, program_check_exception, EXC_XFER_STD)
> @@ -153,6 +153,11 @@ _ENTRY(_start);
> /* Decrementer */
> EXCEPTION(0x900, Decrementer, timer_interrupt, EXC_XFER_LITE)
>
> + /* With VMAP_STACK there's not enough room for this at 0x600 */
> + . = 0xa00
> +.Lalignment_exception_ool:
> + EXC_XFER_STD(0x600, alignment_exception)
> +
> /* System call */
> . = 0xc00
> SystemCall:
> --
> 2.21.1