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* [PATCH] RISC-V: Add the directive for alignment of stvec's value
@ 2018-06-21  1:40 ` Zong Li
  0 siblings, 0 replies; 10+ messages in thread
From: Zong Li @ 2018-06-21  1:40 UTC (permalink / raw)
  To: palmer, aou, linux-riscv, linux-kernel; +Cc: Zong Li, greentime

The stvec's value must be 4 byte alignment by specification definition.
This directive avoids to stvec be set the non-alignment value by the
following code in head.S

 /* Point stvec to virtual address of intruction after satp write */
la a0, 1f
add a0, a0, a1
csrw stvec, a0

Signed-off-by: Zong Li <zong@andestech.com>
---
 arch/riscv/kernel/head.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 396ec7b349ce..ae7b204f531c 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -94,6 +94,7 @@ relocate:
 	or a0, a0, a1
 	sfence.vma
 	csrw sptbr, a0
+.align 2
 1:
 	/* Set trap vector to spin forever to help debug */
 	la a0, .Lsecondary_park
-- 
2.16.1


^ permalink raw reply related	[flat|nested] 10+ messages in thread

* [PATCH] RISC-V: Add the directive for alignment of stvec's value
@ 2018-06-21  1:40 ` Zong Li
  0 siblings, 0 replies; 10+ messages in thread
From: Zong Li @ 2018-06-21  1:40 UTC (permalink / raw)
  To: linux-riscv

The stvec's value must be 4 byte alignment by specification definition.
This directive avoids to stvec be set the non-alignment value by the
following code in head.S

 /* Point stvec to virtual address of intruction after satp write */
la a0, 1f
add a0, a0, a1
csrw stvec, a0

Signed-off-by: Zong Li <zong@andestech.com>
---
 arch/riscv/kernel/head.S | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 396ec7b349ce..ae7b204f531c 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -94,6 +94,7 @@ relocate:
 	or a0, a0, a1
 	sfence.vma
 	csrw sptbr, a0
+.align 2
 1:
 	/* Set trap vector to spin forever to help debug */
 	la a0, .Lsecondary_park
-- 
2.16.1

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* Re: [PATCH] RISC-V: Add the directive for alignment of stvec's value
  2018-06-21  1:40 ` Zong Li
@ 2018-08-02  0:38   ` Palmer Dabbelt
  -1 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2018-08-02  0:38 UTC (permalink / raw)
  To: zong; +Cc: aou, linux-riscv, linux-kernel, zong, greentime

On Wed, 20 Jun 2018 18:40:07 PDT (-0700), zong@andestech.com wrote:
> The stvec's value must be 4 byte alignment by specification definition.
> This directive avoids to stvec be set the non-alignment value by the
> following code in head.S
>
>  /* Point stvec to virtual address of intruction after satp write */
> la a0, 1f
> add a0, a0, a1
> csrw stvec, a0
>
> Signed-off-by: Zong Li <zong@andestech.com>
> ---
>  arch/riscv/kernel/head.S | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> index 396ec7b349ce..ae7b204f531c 100644
> --- a/arch/riscv/kernel/head.S
> +++ b/arch/riscv/kernel/head.S
> @@ -94,6 +94,7 @@ relocate:
>  	or a0, a0, a1
>  	sfence.vma
>  	csrw sptbr, a0
> +.align 2
>  1:
>  	/* Set trap vector to spin forever to help debug */
>  	la a0, .Lsecondary_park

I don't think this is actually correct: you shouldn't be aligning the address 
at which stvec is set, but the address that stvec is set to.  If this is fixing 
anything then it's probably just by coincidence as it's causing 
.Lsecondary_park to be aligned.

I think this patch is the correct fix

    diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
    index 6e07ed37bbff..d1beecf1d060 100644
    --- a/arch/riscv/kernel/head.S
    +++ b/arch/riscv/kernel/head.S
    @@ -143,6 +143,7 @@ relocate:
     	tail smp_callin
     #endif

    +.align 2
     .Lsecondary_park:
     	/* We lack SMP support or have too many harts, so park this hart */
     	wfi

Thanks for pointing this out!

^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH] RISC-V: Add the directive for alignment of stvec's value
@ 2018-08-02  0:38   ` Palmer Dabbelt
  0 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2018-08-02  0:38 UTC (permalink / raw)
  To: linux-riscv

On Wed, 20 Jun 2018 18:40:07 PDT (-0700), zong at andestech.com wrote:
> The stvec's value must be 4 byte alignment by specification definition.
> This directive avoids to stvec be set the non-alignment value by the
> following code in head.S
>
>  /* Point stvec to virtual address of intruction after satp write */
> la a0, 1f
> add a0, a0, a1
> csrw stvec, a0
>
> Signed-off-by: Zong Li <zong@andestech.com>
> ---
>  arch/riscv/kernel/head.S | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> index 396ec7b349ce..ae7b204f531c 100644
> --- a/arch/riscv/kernel/head.S
> +++ b/arch/riscv/kernel/head.S
> @@ -94,6 +94,7 @@ relocate:
>  	or a0, a0, a1
>  	sfence.vma
>  	csrw sptbr, a0
> +.align 2
>  1:
>  	/* Set trap vector to spin forever to help debug */
>  	la a0, .Lsecondary_park

I don't think this is actually correct: you shouldn't be aligning the address 
at which stvec is set, but the address that stvec is set to.  If this is fixing 
anything then it's probably just by coincidence as it's causing 
.Lsecondary_park to be aligned.

I think this patch is the correct fix

    diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
    index 6e07ed37bbff..d1beecf1d060 100644
    --- a/arch/riscv/kernel/head.S
    +++ b/arch/riscv/kernel/head.S
    @@ -143,6 +143,7 @@ relocate:
     	tail smp_callin
     #endif

    +.align 2
     .Lsecondary_park:
     	/* We lack SMP support or have too many harts, so park this hart */
     	wfi

Thanks for pointing this out!

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH] RISC-V: Add the directive for alignment of stvec's value
  2018-08-02  0:38   ` Palmer Dabbelt
@ 2018-08-02  1:26     ` Zong Li
  -1 siblings, 0 replies; 10+ messages in thread
From: Zong Li @ 2018-08-02  1:26 UTC (permalink / raw)
  To: Palmer Dabbelt
  Cc: Zong Li, linux-riscv, aou, Linux Kernel Mailing List, greentime

Palmer Dabbelt <palmer@sifive.com> 於 2018年8月2日 週四 上午8:38寫道:
>
> On Wed, 20 Jun 2018 18:40:07 PDT (-0700), zong@andestech.com wrote:
> > The stvec's value must be 4 byte alignment by specification definition.
> > This directive avoids to stvec be set the non-alignment value by the
> > following code in head.S
> >
> >  /* Point stvec to virtual address of intruction after satp write */
> > la a0, 1f
> > add a0, a0, a1
> > csrw stvec, a0
> >
> > Signed-off-by: Zong Li <zong@andestech.com>
> > ---
> >  arch/riscv/kernel/head.S | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> > index 396ec7b349ce..ae7b204f531c 100644
> > --- a/arch/riscv/kernel/head.S
> > +++ b/arch/riscv/kernel/head.S
> > @@ -94,6 +94,7 @@ relocate:
> >       or a0, a0, a1
> >       sfence.vma
> >       csrw sptbr, a0
> > +.align 2
> >  1:
> >       /* Set trap vector to spin forever to help debug */
> >       la a0, .Lsecondary_park
>
> I don't think this is actually correct: you shouldn't be aligning the address
> at which stvec is set, but the address that stvec is set to.  If this is fixing
> anything then it's probably just by coincidence as it's causing
> .Lsecondary_park to be aligned.
>
> I think this patch is the correct fix
>
>     diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
>     index 6e07ed37bbff..d1beecf1d060 100644
>     --- a/arch/riscv/kernel/head.S
>     +++ b/arch/riscv/kernel/head.S
>     @@ -143,6 +143,7 @@ relocate:
>         tail smp_callin
>      #endif
>
>     +.align 2
>      .Lsecondary_park:
>         /* We lack SMP support or have too many harts, so park this hart */
>         wfi
>
> Thanks for pointing this out!
>
The position which I set in this patch is also be set to stvec for jumping to
correct VA at satp enabling. The label .Lsecondary_park is also be set to stvec,
I don't notice it because as you said, this label address is correct
just by coincidence.
I think there are two places need to be aligned.

The first setting as following:
relocate:
        ...
        /* Point stvec to virtual address of intruction after satp write */
        la a0, 1f
        add a0, a0, a1
        csrw stvec, a0    <-----------  first set
        ...
        sfence.vma
        csrw sptbr, a0
1:
        /* Set trap vector to spin forever to help debug */
        la a0, .Lsecondary_park
        csrw stvec, a0

^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH] RISC-V: Add the directive for alignment of stvec's value
@ 2018-08-02  1:26     ` Zong Li
  0 siblings, 0 replies; 10+ messages in thread
From: Zong Li @ 2018-08-02  1:26 UTC (permalink / raw)
  To: linux-riscv

Palmer Dabbelt <palmer@sifive.com> ? 2018?8?2? ?? ??8:38???
>
> On Wed, 20 Jun 2018 18:40:07 PDT (-0700), zong at andestech.com wrote:
> > The stvec's value must be 4 byte alignment by specification definition.
> > This directive avoids to stvec be set the non-alignment value by the
> > following code in head.S
> >
> >  /* Point stvec to virtual address of intruction after satp write */
> > la a0, 1f
> > add a0, a0, a1
> > csrw stvec, a0
> >
> > Signed-off-by: Zong Li <zong@andestech.com>
> > ---
> >  arch/riscv/kernel/head.S | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> > index 396ec7b349ce..ae7b204f531c 100644
> > --- a/arch/riscv/kernel/head.S
> > +++ b/arch/riscv/kernel/head.S
> > @@ -94,6 +94,7 @@ relocate:
> >       or a0, a0, a1
> >       sfence.vma
> >       csrw sptbr, a0
> > +.align 2
> >  1:
> >       /* Set trap vector to spin forever to help debug */
> >       la a0, .Lsecondary_park
>
> I don't think this is actually correct: you shouldn't be aligning the address
> at which stvec is set, but the address that stvec is set to.  If this is fixing
> anything then it's probably just by coincidence as it's causing
> .Lsecondary_park to be aligned.
>
> I think this patch is the correct fix
>
>     diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
>     index 6e07ed37bbff..d1beecf1d060 100644
>     --- a/arch/riscv/kernel/head.S
>     +++ b/arch/riscv/kernel/head.S
>     @@ -143,6 +143,7 @@ relocate:
>         tail smp_callin
>      #endif
>
>     +.align 2
>      .Lsecondary_park:
>         /* We lack SMP support or have too many harts, so park this hart */
>         wfi
>
> Thanks for pointing this out!
>
The position which I set in this patch is also be set to stvec for jumping to
correct VA at satp enabling. The label .Lsecondary_park is also be set to stvec,
I don't notice it because as you said, this label address is correct
just by coincidence.
I think there are two places need to be aligned.

The first setting as following:
relocate:
        ...
        /* Point stvec to virtual address of intruction after satp write */
        la a0, 1f
        add a0, a0, a1
        csrw stvec, a0    <-----------  first set
        ...
        sfence.vma
        csrw sptbr, a0
1:
        /* Set trap vector to spin forever to help debug */
        la a0, .Lsecondary_park
        csrw stvec, a0

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH] RISC-V: Add the directive for alignment of stvec's value
  2018-06-21  1:40 ` Zong Li
@ 2018-08-02 10:05   ` Christoph Hellwig
  -1 siblings, 0 replies; 10+ messages in thread
From: Christoph Hellwig @ 2018-08-02 10:05 UTC (permalink / raw)
  To: Zong Li; +Cc: palmer, aou, linux-riscv, linux-kernel, greentime

On Thu, Jun 21, 2018 at 09:40:07AM +0800, Zong Li wrote:
> The stvec's value must be 4 byte alignment by specification definition.
> This directive avoids to stvec be set the non-alignment value by the
> following code in head.S
> 
>  /* Point stvec to virtual address of intruction after satp write */
> la a0, 1f
> add a0, a0, a1
> csrw stvec, a0
> 
> Signed-off-by: Zong Li <zong@andestech.com>

Just noticed this didn't get picked up yet, so:

Reviewed-by: Christoph Hellwig <hch@lst.de>

^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH] RISC-V: Add the directive for alignment of stvec's value
@ 2018-08-02 10:05   ` Christoph Hellwig
  0 siblings, 0 replies; 10+ messages in thread
From: Christoph Hellwig @ 2018-08-02 10:05 UTC (permalink / raw)
  To: linux-riscv

On Thu, Jun 21, 2018 at 09:40:07AM +0800, Zong Li wrote:
> The stvec's value must be 4 byte alignment by specification definition.
> This directive avoids to stvec be set the non-alignment value by the
> following code in head.S
> 
>  /* Point stvec to virtual address of intruction after satp write */
> la a0, 1f
> add a0, a0, a1
> csrw stvec, a0
> 
> Signed-off-by: Zong Li <zong@andestech.com>

Just noticed this didn't get picked up yet, so:

Reviewed-by: Christoph Hellwig <hch@lst.de>

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: [PATCH] RISC-V: Add the directive for alignment of stvec's value
  2018-08-02  1:26     ` Zong Li
@ 2018-08-04  4:38       ` Palmer Dabbelt
  -1 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2018-08-04  4:38 UTC (permalink / raw)
  To: zongbox; +Cc: zong, linux-riscv, aou, linux-kernel, greentime

On Wed, 01 Aug 2018 18:26:48 PDT (-0700), zongbox@gmail.com wrote:
> Palmer Dabbelt <palmer@sifive.com> 於 2018年8月2日 週四 上午8:38寫道:
>>
>> On Wed, 20 Jun 2018 18:40:07 PDT (-0700), zong@andestech.com wrote:
>> > The stvec's value must be 4 byte alignment by specification definition.
>> > This directive avoids to stvec be set the non-alignment value by the
>> > following code in head.S
>> >
>> >  /* Point stvec to virtual address of intruction after satp write */
>> > la a0, 1f
>> > add a0, a0, a1
>> > csrw stvec, a0
>> >
>> > Signed-off-by: Zong Li <zong@andestech.com>
>> > ---
>> >  arch/riscv/kernel/head.S | 1 +
>> >  1 file changed, 1 insertion(+)
>> >
>> > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
>> > index 396ec7b349ce..ae7b204f531c 100644
>> > --- a/arch/riscv/kernel/head.S
>> > +++ b/arch/riscv/kernel/head.S
>> > @@ -94,6 +94,7 @@ relocate:
>> >       or a0, a0, a1
>> >       sfence.vma
>> >       csrw sptbr, a0
>> > +.align 2
>> >  1:
>> >       /* Set trap vector to spin forever to help debug */
>> >       la a0, .Lsecondary_park
>>
>> I don't think this is actually correct: you shouldn't be aligning the address
>> at which stvec is set, but the address that stvec is set to.  If this is fixing
>> anything then it's probably just by coincidence as it's causing
>> .Lsecondary_park to be aligned.
>>
>> I think this patch is the correct fix
>>
>>     diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
>>     index 6e07ed37bbff..d1beecf1d060 100644
>>     --- a/arch/riscv/kernel/head.S
>>     +++ b/arch/riscv/kernel/head.S
>>     @@ -143,6 +143,7 @@ relocate:
>>         tail smp_callin
>>      #endif
>>
>>     +.align 2
>>      .Lsecondary_park:
>>         /* We lack SMP support or have too many harts, so park this hart */
>>         wfi
>>
>> Thanks for pointing this out!
>>
> The position which I set in this patch is also be set to stvec for jumping to
> correct VA at satp enabling. The label .Lsecondary_park is also be set to stvec,
> I don't notice it because as you said, this label address is correct
> just by coincidence.
> I think there are two places need to be aligned.
>
> The first setting as following:
> relocate:
>         ...
>         /* Point stvec to virtual address of intruction after satp write */
>         la a0, 1f
>         add a0, a0, a1
>         csrw stvec, a0    <-----------  first set
>         ...
>         sfence.vma
>         csrw sptbr, a0
> 1:
>         /* Set trap vector to spin forever to help debug */
>         la a0, .Lsecondary_park
>         csrw stvec, a0

I agree.  I think this should do it:

    commit a8c5f596bcd528c5468d621bc84cd901632a912a
    gpg: Signature made Fri 03 Aug 2018 09:13:56 PM PDT
    gpg:                using RSA key 00CE76D1834960DFCE886DF8EF4CA1502CCBAB41
    gpg:                issuer "palmer@dabbelt.com"
    gpg: Good signature from "Palmer Dabbelt <palmer@dabbelt.com>" [ultimate]
    gpg:                 aka "Palmer Dabbelt <palmer@sifive.com>" [ultimate]
    Author: Palmer Dabbelt <palmer@sifive.com>
    Date:   Wed Aug 1 17:38:30 2018 -0700
    
        RISC-V: Align early stvec targets
        
        The ISA mandantes that stvec is 4-byte aligned, but we weren't actually
        respecting in the early boot code.  These trap vector are never expected
        to actually be used unless there's a bug in early in the boot process of
        the kernel, which explains why the bug wasn't noticed until recently.
        
        Thanks to Zong for finding the bug!
        
        CC: zong@andestech.com
        Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
    
    diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
    index 6e07ed37bbff..c4d2c63f9a29 100644
    --- a/arch/riscv/kernel/head.S
    +++ b/arch/riscv/kernel/head.S
    @@ -94,6 +94,7 @@ relocate:
     	or a0, a0, a1
     	sfence.vma
     	csrw sptbr, a0
    +.align 2
     1:
     	/* Set trap vector to spin forever to help debug */
     	la a0, .Lsecondary_park
    @@ -143,6 +144,7 @@ relocate:
     	tail smp_callin
     #endif
     
    +.align 2
     .Lsecondary_park:
     	/* We lack SMP support or have too many harts, so park this hart */
     	wfi


^ permalink raw reply	[flat|nested] 10+ messages in thread

* [PATCH] RISC-V: Add the directive for alignment of stvec's value
@ 2018-08-04  4:38       ` Palmer Dabbelt
  0 siblings, 0 replies; 10+ messages in thread
From: Palmer Dabbelt @ 2018-08-04  4:38 UTC (permalink / raw)
  To: linux-riscv

On Wed, 01 Aug 2018 18:26:48 PDT (-0700), zongbox at gmail.com wrote:
> Palmer Dabbelt <palmer@sifive.com> ? 2018?8?2? ?? ??8:38???
>>
>> On Wed, 20 Jun 2018 18:40:07 PDT (-0700), zong at andestech.com wrote:
>> > The stvec's value must be 4 byte alignment by specification definition.
>> > This directive avoids to stvec be set the non-alignment value by the
>> > following code in head.S
>> >
>> >  /* Point stvec to virtual address of intruction after satp write */
>> > la a0, 1f
>> > add a0, a0, a1
>> > csrw stvec, a0
>> >
>> > Signed-off-by: Zong Li <zong@andestech.com>
>> > ---
>> >  arch/riscv/kernel/head.S | 1 +
>> >  1 file changed, 1 insertion(+)
>> >
>> > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
>> > index 396ec7b349ce..ae7b204f531c 100644
>> > --- a/arch/riscv/kernel/head.S
>> > +++ b/arch/riscv/kernel/head.S
>> > @@ -94,6 +94,7 @@ relocate:
>> >       or a0, a0, a1
>> >       sfence.vma
>> >       csrw sptbr, a0
>> > +.align 2
>> >  1:
>> >       /* Set trap vector to spin forever to help debug */
>> >       la a0, .Lsecondary_park
>>
>> I don't think this is actually correct: you shouldn't be aligning the address
>> at which stvec is set, but the address that stvec is set to.  If this is fixing
>> anything then it's probably just by coincidence as it's causing
>> .Lsecondary_park to be aligned.
>>
>> I think this patch is the correct fix
>>
>>     diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
>>     index 6e07ed37bbff..d1beecf1d060 100644
>>     --- a/arch/riscv/kernel/head.S
>>     +++ b/arch/riscv/kernel/head.S
>>     @@ -143,6 +143,7 @@ relocate:
>>         tail smp_callin
>>      #endif
>>
>>     +.align 2
>>      .Lsecondary_park:
>>         /* We lack SMP support or have too many harts, so park this hart */
>>         wfi
>>
>> Thanks for pointing this out!
>>
> The position which I set in this patch is also be set to stvec for jumping to
> correct VA at satp enabling. The label .Lsecondary_park is also be set to stvec,
> I don't notice it because as you said, this label address is correct
> just by coincidence.
> I think there are two places need to be aligned.
>
> The first setting as following:
> relocate:
>         ...
>         /* Point stvec to virtual address of intruction after satp write */
>         la a0, 1f
>         add a0, a0, a1
>         csrw stvec, a0    <-----------  first set
>         ...
>         sfence.vma
>         csrw sptbr, a0
> 1:
>         /* Set trap vector to spin forever to help debug */
>         la a0, .Lsecondary_park
>         csrw stvec, a0

I agree.  I think this should do it:

    commit a8c5f596bcd528c5468d621bc84cd901632a912a
    gpg: Signature made Fri 03 Aug 2018 09:13:56 PM PDT
    gpg:                using RSA key 00CE76D1834960DFCE886DF8EF4CA1502CCBAB41
    gpg:                issuer "palmer at dabbelt.com"
    gpg: Good signature from "Palmer Dabbelt <palmer@dabbelt.com>" [ultimate]
    gpg:                 aka "Palmer Dabbelt <palmer@sifive.com>" [ultimate]
    Author: Palmer Dabbelt <palmer@sifive.com>
    Date:   Wed Aug 1 17:38:30 2018 -0700
    
        RISC-V: Align early stvec targets
        
        The ISA mandantes that stvec is 4-byte aligned, but we weren't actually
        respecting in the early boot code.  These trap vector are never expected
        to actually be used unless there's a bug in early in the boot process of
        the kernel, which explains why the bug wasn't noticed until recently.
        
        Thanks to Zong for finding the bug!
        
        CC: zong at andestech.com
        Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
    
    diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
    index 6e07ed37bbff..c4d2c63f9a29 100644
    --- a/arch/riscv/kernel/head.S
    +++ b/arch/riscv/kernel/head.S
    @@ -94,6 +94,7 @@ relocate:
     	or a0, a0, a1
     	sfence.vma
     	csrw sptbr, a0
    +.align 2
     1:
     	/* Set trap vector to spin forever to help debug */
     	la a0, .Lsecondary_park
    @@ -143,6 +144,7 @@ relocate:
     	tail smp_callin
     #endif
     
    +.align 2
     .Lsecondary_park:
     	/* We lack SMP support or have too many harts, so park this hart */
     	wfi

^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2018-08-04  4:46 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-06-21  1:40 [PATCH] RISC-V: Add the directive for alignment of stvec's value Zong Li
2018-06-21  1:40 ` Zong Li
2018-08-02  0:38 ` Palmer Dabbelt
2018-08-02  0:38   ` Palmer Dabbelt
2018-08-02  1:26   ` Zong Li
2018-08-02  1:26     ` Zong Li
2018-08-04  4:38     ` Palmer Dabbelt
2018-08-04  4:38       ` Palmer Dabbelt
2018-08-02 10:05 ` Christoph Hellwig
2018-08-02 10:05   ` Christoph Hellwig

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