Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Carlos Eduardo de Paula]

Golang has been recently upstreamed and I've been building multiple
versions on my Unleashed board successfully with kernel 5.3-rc4 and
previous.

I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
Golang doesn't build anymore failing on multiple points and
segfaulting as well.

I've captured a few logs with the error building here:

I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
out that the commit below is the starting point.

eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
commit eb93685847a9055283d05951c1b205e737f38533
Author: Paul Walmsley <paul.walmsley@sifive.com>
Date: Wed Aug 7 19:07:34 2019 -0700

riscv: fix flush_tlb_range() end address for flush_tlb_page()

The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
is set is wrong. It passes zero to flush_tlb_range() as the final
address to flush, but it should be at least 'addr'.

Some other Linux architecture ports use the beginning address to
flush, plus PAGE_SIZE, as the final address to flush. This might
flush slightly more than what's needed, but it seems unlikely that
being more clever would improve anything. So let's just take that
implementation for now.

While here, convert the macro into a static inline function, primarily
to avoid unintentional multiple evaluations of 'addr'.

This second version of the patch fixes a coding style issue found by
Christoph Hellwig <hch@lst.de>.

Reported-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

:040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch

> git bisect visualize
eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
for flush_tlb_page() HEAD, refs/bisect/bad


> git diff eb93685^!

```diff
diff --git a/arch/riscv/include/asm/tlbflush.h
b/arch/riscv/include/asm/tlbflush.h
index 687dd19..4d9bbe8 100644
--- a/arch/riscv/include/asm/tlbflush.h
+++ b/arch/riscv/include/asm/tlbflush.h
@@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
cpumask *cmask, unsigned long start,
}

#define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
-#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
+
#define flush_tlb_range(vma, start, end) \
remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
-#define flush_tlb_mm(mm) \
+
+static inline void flush_tlb_page(struct vm_area_struct *vma,
+ unsigned long addr)
+{
+ flush_tlb_range(vma, addr, addr + PAGE_SIZE);
+}
+
+#define flush_tlb_mm(mm) \
remote_sfence_vma(mm_cpumask(mm), 0, -1)

#endif /* CONFIG_SMP */
```

I was not able to revert this change from recent v5.5.0 so I don't
know if this is the problem or some close commits:

> git log 2b245b8b..2f478b60 |grep riscv
2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
for flush_tlb_page()

Carlos
-- 
________________________________________
Carlos Eduardo de Paula
me@carlosedp.com
http://carlosedp.com
http://twitter.com/carlosedp
Linkedin
________________________________________

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[David Abdurachmanov]

On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
<me@carlosedp.com> wrote:
>
> Golang has been recently upstreamed and I've been building multiple
> versions on my Unleashed board successfully with kernel 5.3-rc4 and
> previous.
>
> I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
> Golang doesn't build anymore failing on multiple points and
> segfaulting as well.

Could you also mention what version of OpenSBI you use?
Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?

>
> I've captured a few logs with the error building here:
>
> I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
> out that the commit below is the starting point.
>
> eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
> commit eb93685847a9055283d05951c1b205e737f38533
> Author: Paul Walmsley <paul.walmsley@sifive.com>
> Date: Wed Aug 7 19:07:34 2019 -0700
>
> riscv: fix flush_tlb_range() end address for flush_tlb_page()
>
> The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
> is set is wrong. It passes zero to flush_tlb_range() as the final
> address to flush, but it should be at least 'addr'.
>
> Some other Linux architecture ports use the beginning address to
> flush, plus PAGE_SIZE, as the final address to flush. This might
> flush slightly more than what's needed, but it seems unlikely that
> being more clever would improve anything. So let's just take that
> implementation for now.
>
> While here, convert the macro into a static inline function, primarily
> to avoid unintentional multiple evaluations of 'addr'.
>
> This second version of the patch fixes a coding style issue found by
> Christoph Hellwig <hch@lst.de>.
>
> Reported-by: Andreas Schwab <schwab@suse.de>
> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
>
> :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
> 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
>
> > git bisect visualize
> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> for flush_tlb_page() HEAD, refs/bisect/bad
>
>
> > git diff eb93685^!
>
> ```diff
> diff --git a/arch/riscv/include/asm/tlbflush.h
> b/arch/riscv/include/asm/tlbflush.h
> index 687dd19..4d9bbe8 100644
> --- a/arch/riscv/include/asm/tlbflush.h
> +++ b/arch/riscv/include/asm/tlbflush.h
> @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
> cpumask *cmask, unsigned long start,
> }
>
> #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
> -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
> +
> #define flush_tlb_range(vma, start, end) \
> remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
> -#define flush_tlb_mm(mm) \
> +
> +static inline void flush_tlb_page(struct vm_area_struct *vma,
> + unsigned long addr)
> +{
> + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
> +}
> +
> +#define flush_tlb_mm(mm) \
> remote_sfence_vma(mm_cpumask(mm), 0, -1)
>
> #endif /* CONFIG_SMP */
> ```
>
> I was not able to revert this change from recent v5.5.0 so I don't
> know if this is the problem or some close commits:
>
> > git log 2b245b8b..2f478b60 |grep riscv
> 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
> git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
> 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
> 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> for flush_tlb_page()
>
> Carlos
> --
> ________________________________________
> Carlos Eduardo de Paula
> me@carlosedp.com
> http://carlosedp.com
> http://twitter.com/carlosedp
> Linkedin
> ________________________________________
>

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Carlos Eduardo de Paula]

My board is running:

SiFive FSBL:       2018-03-20
OpenSBI v0.5-44-g049ad0b
U-Boot 2020.01-dirty (Jan 08 2020 - 18:05:52 -0200)

All build on january 8 using the guide I've wrote here
(https://github.com/carlosedp/riscv-bringup/tree/master/unleashed)
after our talks.

Haven't tested newer versions on Qemu, might build it to give a try. I
have v5.4-rc3 built for Qemu and it works fine.

Carlos

On Fri, Jan 31, 2020 at 10:32 AM David Abdurachmanov
<david.abdurachmanov@gmail.com> wrote:
>
> On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
> <me@carlosedp.com> wrote:
> >
> > Golang has been recently upstreamed and I've been building multiple
> > versions on my Unleashed board successfully with kernel 5.3-rc4 and
> > previous.
> >
> > I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
> > Golang doesn't build anymore failing on multiple points and
> > segfaulting as well.
>
> Could you also mention what version of OpenSBI you use?
> Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?
>
> >
> > I've captured a few logs with the error building here:
> >
> > I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
> > out that the commit below is the starting point.
> >
> > eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
> > commit eb93685847a9055283d05951c1b205e737f38533
> > Author: Paul Walmsley <paul.walmsley@sifive.com>
> > Date: Wed Aug 7 19:07:34 2019 -0700
> >
> > riscv: fix flush_tlb_range() end address for flush_tlb_page()
> >
> > The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
> > is set is wrong. It passes zero to flush_tlb_range() as the final
> > address to flush, but it should be at least 'addr'.
> >
> > Some other Linux architecture ports use the beginning address to
> > flush, plus PAGE_SIZE, as the final address to flush. This might
> > flush slightly more than what's needed, but it seems unlikely that
> > being more clever would improve anything. So let's just take that
> > implementation for now.
> >
> > While here, convert the macro into a static inline function, primarily
> > to avoid unintentional multiple evaluations of 'addr'.
> >
> > This second version of the patch fixes a coding style issue found by
> > Christoph Hellwig <hch@lst.de>.
> >
> > Reported-by: Andreas Schwab <schwab@suse.de>
> > Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
> > Reviewed-by: Christoph Hellwig <hch@lst.de>
> >
> > :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
> > 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
> >
> > > git bisect visualize
> > eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> > for flush_tlb_page() HEAD, refs/bisect/bad
> >
> >
> > > git diff eb93685^!
> >
> > ```diff
> > diff --git a/arch/riscv/include/asm/tlbflush.h
> > b/arch/riscv/include/asm/tlbflush.h
> > index 687dd19..4d9bbe8 100644
> > --- a/arch/riscv/include/asm/tlbflush.h
> > +++ b/arch/riscv/include/asm/tlbflush.h
> > @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
> > cpumask *cmask, unsigned long start,
> > }
> >
> > #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
> > -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
> > +
> > #define flush_tlb_range(vma, start, end) \
> > remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
> > -#define flush_tlb_mm(mm) \
> > +
> > +static inline void flush_tlb_page(struct vm_area_struct *vma,
> > + unsigned long addr)
> > +{
> > + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
> > +}
> > +
> > +#define flush_tlb_mm(mm) \
> > remote_sfence_vma(mm_cpumask(mm), 0, -1)
> >
> > #endif /* CONFIG_SMP */
> > ```
> >
> > I was not able to revert this change from recent v5.5.0 so I don't
> > know if this is the problem or some close commits:
> >
> > > git log 2b245b8b..2f478b60 |grep riscv
> > 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
> > git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
> > 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
> > 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
> > eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> > for flush_tlb_page()
> >
> > Carlos
> > --
> > ________________________________________
> > Carlos Eduardo de Paula
> > me@carlosedp.com
> > http://carlosedp.com
> > http://twitter.com/carlosedp
> > Linkedin
> > ________________________________________
> >
>


-- 
________________________________________
Carlos Eduardo de Paula
me@carlosedp.com
http://carlosedp.com
http://twitter.com/carlosedp
Linkedin
________________________________________

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Carlos Eduardo de Paula]

Updating this issue, I've built the same Golang tree (master) on Qemu
using the same kernel Image v5.5.0 I have on Unleashed and it built
successfully:

root@qemuriscv:~/go/src# time ./make.bash
Building Go cmd/dist using /root/go-linux-riscv64-bootstrap. (devel
+a858d15f11 13 hours ago linux/riscv64)
Building Go toolchain1 using /root/go-linux-riscv64-bootstrap.
Building Go bootstrap cmd/go (go_bootstrap) using Go toolchain1.
Building Go toolchain2 using go_bootstrap and Go toolchain1.
Building Go toolchain3 using go_bootstrap and Go toolchain2.
Building packages and commands for linux/riscv64.
---
Installed Go for linux/riscv64 in /root/go
Installed commands in /root/go/bin

real    43m19.946s
user    120m34.147s
sys    66m34.964s
Linux qemuriscv 5.5.0-dirty #3 SMP Fri Jan 31 00:13:59 -02 2020
riscv64 GNU/Linux
root@qemuriscv:~/go/src# ../bin/go version
go version devel +6e592c2 Fri Jan 31 14:46:05 2020 +0000 linux/riscv64


Also tried updating to latest opensbi commit as of today and still
seeing same error on Unleashed.


On Fri, Jan 31, 2020 at 11:20 AM Carlos Eduardo de Paula
<me@carlosedp.com> wrote:
>
> My board is running:
>
> SiFive FSBL:       2018-03-20
> OpenSBI v0.5-44-g049ad0b
> U-Boot 2020.01-dirty (Jan 08 2020 - 18:05:52 -0200)
>
> All build on january 8 using the guide I've wrote here
> (https://github.com/carlosedp/riscv-bringup/tree/master/unleashed)
> after our talks.
>
> Haven't tested newer versions on Qemu, might build it to give a try. I
> have v5.4-rc3 built for Qemu and it works fine.
>
> Carlos
>
> On Fri, Jan 31, 2020 at 10:32 AM David Abdurachmanov
> <david.abdurachmanov@gmail.com> wrote:
> >
> > On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
> > <me@carlosedp.com> wrote:
> > >
> > > Golang has been recently upstreamed and I've been building multiple
> > > versions on my Unleashed board successfully with kernel 5.3-rc4 and
> > > previous.
> > >
> > > I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
> > > Golang doesn't build anymore failing on multiple points and
> > > segfaulting as well.
> >
> > Could you also mention what version of OpenSBI you use?
> > Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?
> >
> > >
> > > I've captured a few logs with the error building here:
> > >
> > > I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
> > > out that the commit below is the starting point.
> > >
> > > eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
> > > commit eb93685847a9055283d05951c1b205e737f38533
> > > Author: Paul Walmsley <paul.walmsley@sifive.com>
> > > Date: Wed Aug 7 19:07:34 2019 -0700
> > >
> > > riscv: fix flush_tlb_range() end address for flush_tlb_page()
> > >
> > > The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
> > > is set is wrong. It passes zero to flush_tlb_range() as the final
> > > address to flush, but it should be at least 'addr'.
> > >
> > > Some other Linux architecture ports use the beginning address to
> > > flush, plus PAGE_SIZE, as the final address to flush. This might
> > > flush slightly more than what's needed, but it seems unlikely that
> > > being more clever would improve anything. So let's just take that
> > > implementation for now.
> > >
> > > While here, convert the macro into a static inline function, primarily
> > > to avoid unintentional multiple evaluations of 'addr'.
> > >
> > > This second version of the patch fixes a coding style issue found by
> > > Christoph Hellwig <hch@lst.de>.
> > >
> > > Reported-by: Andreas Schwab <schwab@suse.de>
> > > Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
> > > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > >
> > > :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
> > > 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
> > >
> > > > git bisect visualize
> > > eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> > > for flush_tlb_page() HEAD, refs/bisect/bad
> > >
> > >
> > > > git diff eb93685^!
> > >
> > > ```diff
> > > diff --git a/arch/riscv/include/asm/tlbflush.h
> > > b/arch/riscv/include/asm/tlbflush.h
> > > index 687dd19..4d9bbe8 100644
> > > --- a/arch/riscv/include/asm/tlbflush.h
> > > +++ b/arch/riscv/include/asm/tlbflush.h
> > > @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
> > > cpumask *cmask, unsigned long start,
> > > }
> > >
> > > #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
> > > -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
> > > +
> > > #define flush_tlb_range(vma, start, end) \
> > > remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
> > > -#define flush_tlb_mm(mm) \
> > > +
> > > +static inline void flush_tlb_page(struct vm_area_struct *vma,
> > > + unsigned long addr)
> > > +{
> > > + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
> > > +}
> > > +
> > > +#define flush_tlb_mm(mm) \
> > > remote_sfence_vma(mm_cpumask(mm), 0, -1)
> > >
> > > #endif /* CONFIG_SMP */
> > > ```
> > >
> > > I was not able to revert this change from recent v5.5.0 so I don't
> > > know if this is the problem or some close commits:
> > >
> > > > git log 2b245b8b..2f478b60 |grep riscv
> > > 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
> > > git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
> > > 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
> > > 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
> > > eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> > > for flush_tlb_page()
> > >
> > > Carlos
> > > --
> > > ________________________________________
> > > Carlos Eduardo de Paula
> > > me@carlosedp.com
> > > http://carlosedp.com
> > > http://twitter.com/carlosedp
> > > Linkedin
> > > ________________________________________
> > >
> >
>
>
> --
> ________________________________________
> Carlos Eduardo de Paula
> me@carlosedp.com
> http://carlosedp.com
> http://twitter.com/carlosedp
> Linkedin
> ________________________________________



-- 
________________________________________
Carlos Eduardo de Paula
me@carlosedp.com
http://carlosedp.com
http://twitter.com/carlosedp
Linkedin
________________________________________

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Atish Patra]

On Fri, Jan 31, 2020 at 8:32 AM Carlos Eduardo de Paula
<me@carlosedp.com> wrote:
>
> Updating this issue, I've built the same Golang tree (master) on Qemu
> using the same kernel Image v5.5.0 I have on Unleashed and it built
> successfully:
>
> root@qemuriscv:~/go/src# time ./make.bash
> Building Go cmd/dist using /root/go-linux-riscv64-bootstrap. (devel
> +a858d15f11 13 hours ago linux/riscv64)
> Building Go toolchain1 using /root/go-linux-riscv64-bootstrap.
> Building Go bootstrap cmd/go (go_bootstrap) using Go toolchain1.
> Building Go toolchain2 using go_bootstrap and Go toolchain1.
> Building Go toolchain3 using go_bootstrap and Go toolchain2.
> Building packages and commands for linux/riscv64.
> ---
> Installed Go for linux/riscv64 in /root/go
> Installed commands in /root/go/bin
>
> real    43m19.946s
> user    120m34.147s
> sys    66m34.964s
> Linux qemuriscv 5.5.0-dirty #3 SMP Fri Jan 31 00:13:59 -02 2020
> riscv64 GNU/Linux
> root@qemuriscv:~/go/src# ../bin/go version
> go version devel +6e592c2 Fri Jan 31 14:46:05 2020 +0000 linux/riscv64
>
>
> Also tried updating to latest opensbi commit as of today and still
> seeing same error on Unleashed.
>
>

Resending it as 1st one did not seem to go through for some reason

You might be hitting the tlb flushing hardware errata on unleashed.
IIRC, anything other than full tlb flush
is broken on unleashed. I don't have the exact errata number or a link
that I can point to. May be Paul or somebody else from sifive
can share that so that we can document it as well.

Can you try this patch in OpenSBI? This forces OpenSBI to do a full
flush every time for HiFive Unleashed.

diff --git a/platform/sifive/fu540/platform.c b/platform/sifive/fu540/platform.c
index c8ead9dede23..e36338d2903f 100644
--- a/platform/sifive/fu540/platform.c
+++ b/platform/sifive/fu540/platform.c
@@ -218,5 +218,6 @@ const struct sbi_platform platform = {
        .hart_count             = FU540_HART_COUNT,
        .hart_stack_size        = FU540_HART_STACK_SIZE,
        .disabled_hart_mask     = FU540_HARITD_DISABLED,
+       .tlb_range_flush_limit  = 0,
        .platform_ops_addr      = (unsigned long)&platform_ops
 };

> On Fri, Jan 31, 2020 at 11:20 AM Carlos Eduardo de Paula
> <me@carlosedp.com> wrote:
> >
> > My board is running:
> >
> > SiFive FSBL:       2018-03-20
> > OpenSBI v0.5-44-g049ad0b
> > U-Boot 2020.01-dirty (Jan 08 2020 - 18:05:52 -0200)
> >
> > All build on january 8 using the guide I've wrote here
> > (https://github.com/carlosedp/riscv-bringup/tree/master/unleashed)
> > after our talks.
> >
> > Haven't tested newer versions on Qemu, might build it to give a try. I
> > have v5.4-rc3 built for Qemu and it works fine.
> >
> > Carlos
> >
> > On Fri, Jan 31, 2020 at 10:32 AM David Abdurachmanov
> > <david.abdurachmanov@gmail.com> wrote:
> > >
> > > On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
> > > <me@carlosedp.com> wrote:
> > > >
> > > > Golang has been recently upstreamed and I've been building multiple
> > > > versions on my Unleashed board successfully with kernel 5.3-rc4 and
> > > > previous.
> > > >
> > > > I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
> > > > Golang doesn't build anymore failing on multiple points and
> > > > segfaulting as well.
> > >
> > > Could you also mention what version of OpenSBI you use?
> > > Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?
> > >
> > > >
> > > > I've captured a few logs with the error building here:
> > > >
> > > > I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
> > > > out that the commit below is the starting point.
> > > >
> > > > eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
> > > > commit eb93685847a9055283d05951c1b205e737f38533
> > > > Author: Paul Walmsley <paul.walmsley@sifive.com>
> > > > Date: Wed Aug 7 19:07:34 2019 -0700
> > > >
> > > > riscv: fix flush_tlb_range() end address for flush_tlb_page()
> > > >
> > > > The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
> > > > is set is wrong. It passes zero to flush_tlb_range() as the final
> > > > address to flush, but it should be at least 'addr'.
> > > >
> > > > Some other Linux architecture ports use the beginning address to
> > > > flush, plus PAGE_SIZE, as the final address to flush. This might
> > > > flush slightly more than what's needed, but it seems unlikely that
> > > > being more clever would improve anything. So let's just take that
> > > > implementation for now.
> > > >
> > > > While here, convert the macro into a static inline function, primarily
> > > > to avoid unintentional multiple evaluations of 'addr'.
> > > >
> > > > This second version of the patch fixes a coding style issue found by
> > > > Christoph Hellwig <hch@lst.de>.
> > > >
> > > > Reported-by: Andreas Schwab <schwab@suse.de>
> > > > Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
> > > > Reviewed-by: Christoph Hellwig <hch@lst.de>
> > > >
> > > > :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
> > > > 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
> > > >
> > > > > git bisect visualize
> > > > eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> > > > for flush_tlb_page() HEAD, refs/bisect/bad
> > > >
> > > >
> > > > > git diff eb93685^!
> > > >
> > > > ```diff
> > > > diff --git a/arch/riscv/include/asm/tlbflush.h
> > > > b/arch/riscv/include/asm/tlbflush.h
> > > > index 687dd19..4d9bbe8 100644
> > > > --- a/arch/riscv/include/asm/tlbflush.h
> > > > +++ b/arch/riscv/include/asm/tlbflush.h
> > > > @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
> > > > cpumask *cmask, unsigned long start,
> > > > }
> > > >
> > > > #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
> > > > -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
> > > > +
> > > > #define flush_tlb_range(vma, start, end) \
> > > > remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
> > > > -#define flush_tlb_mm(mm) \
> > > > +
> > > > +static inline void flush_tlb_page(struct vm_area_struct *vma,
> > > > + unsigned long addr)
> > > > +{
> > > > + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
> > > > +}
> > > > +
> > > > +#define flush_tlb_mm(mm) \
> > > > remote_sfence_vma(mm_cpumask(mm), 0, -1)
> > > >
> > > > #endif /* CONFIG_SMP */
> > > > ```
> > > >
> > > > I was not able to revert this change from recent v5.5.0 so I don't
> > > > know if this is the problem or some close commits:
> > > >
> > > > > git log 2b245b8b..2f478b60 |grep riscv
> > > > 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
> > > > git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
> > > > 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
> > > > 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
> > > > eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> > > > for flush_tlb_page()
> > > >
> > > > Carlos
> > > > --
> > > > ________________________________________
> > > > Carlos Eduardo de Paula
> > > > me@carlosedp.com
> > > > http://carlosedp.com
> > > > http://twitter.com/carlosedp
> > > > Linkedin
> > > > ________________________________________
> > > >
> > >
> >
> >
> > --
> > ________________________________________
> > Carlos Eduardo de Paula
> > me@carlosedp.com
> > http://carlosedp.com
> > http://twitter.com/carlosedp
> > Linkedin
> > ________________________________________
>
>
>
> --
> ________________________________________
> Carlos Eduardo de Paula
> me@carlosedp.com
> http://carlosedp.com
> http://twitter.com/carlosedp
> Linkedin
> ________________________________________
>


-- 
Regards,
Atish

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[William Grant]

[-- Attachment #1.1: Type: text/plain, Size: 8419 bytes --]

On 1/2/20 3:58 pm, Atish Patra wrote:
> On Fri, Jan 31, 2020 at 8:32 AM Carlos Eduardo de Paula
> <me@carlosedp.com> wrote:
>>
>> Updating this issue, I've built the same Golang tree (master) on Qemu
>> using the same kernel Image v5.5.0 I have on Unleashed and it built
>> successfully:
>>
>> root@qemuriscv:~/go/src# time ./make.bash
>> Building Go cmd/dist using /root/go-linux-riscv64-bootstrap. (devel
>> +a858d15f11 13 hours ago linux/riscv64)
>> Building Go toolchain1 using /root/go-linux-riscv64-bootstrap.
>> Building Go bootstrap cmd/go (go_bootstrap) using Go toolchain1.
>> Building Go toolchain2 using go_bootstrap and Go toolchain1.
>> Building Go toolchain3 using go_bootstrap and Go toolchain2.
>> Building packages and commands for linux/riscv64.
>> ---
>> Installed Go for linux/riscv64 in /root/go
>> Installed commands in /root/go/bin
>>
>> real    43m19.946s
>> user    120m34.147s
>> sys    66m34.964s
>> Linux qemuriscv 5.5.0-dirty #3 SMP Fri Jan 31 00:13:59 -02 2020
>> riscv64 GNU/Linux
>> root@qemuriscv:~/go/src# ../bin/go version
>> go version devel +6e592c2 Fri Jan 31 14:46:05 2020 +0000 linux/riscv64
>>
>>
>> Also tried updating to latest opensbi commit as of today and still
>> seeing same error on Unleashed.
>>
>>
> 
> Resending it as 1st one did not seem to go through for some reason
> 
> You might be hitting the tlb flushing hardware errata on unleashed.
> IIRC, anything other than full tlb flush
> is broken on unleashed. I don't have the exact errata number or a link
> that I can point to. May be Paul or somebody else from sifive
> can share that so that we can document it as well.
> 
> Can you try this patch in OpenSBI? This forces OpenSBI to do a full
> flush every time for HiFive Unleashed.

I've separately been trying to track this down for a couple of days, and
indeed, adjusting OpenSBI to always do a full flush is the easiest
workaround. I haven't seen any public reference to TLB errata on the
SoC, but it would explain a lot.

For now I've found that existing kernels with OpenSBI patched to always
do a full flush, or kernels patched to do a full flush at the end of
wp_page_copy, get Go building stably. I don't know if there's something
special about wp_page_copy that tickles the bug, or if it's just called
often enough that it papers over incomplete flushes elsewhere.

> diff --git a/platform/sifive/fu540/platform.c b/platform/sifive/fu540/platform.c
> index c8ead9dede23..e36338d2903f 100644
> --- a/platform/sifive/fu540/platform.c
> +++ b/platform/sifive/fu540/platform.c
> @@ -218,5 +218,6 @@ const struct sbi_platform platform = {
>         .hart_count             = FU540_HART_COUNT,
>         .hart_stack_size        = FU540_HART_STACK_SIZE,
>         .disabled_hart_mask     = FU540_HARITD_DISABLED,
> +       .tlb_range_flush_limit  = 0,
>         .platform_ops_addr      = (unsigned long)&platform_ops
>  };
> 
>> On Fri, Jan 31, 2020 at 11:20 AM Carlos Eduardo de Paula
>> <me@carlosedp.com> wrote:
>>>
>>> My board is running:
>>>
>>> SiFive FSBL:       2018-03-20
>>> OpenSBI v0.5-44-g049ad0b
>>> U-Boot 2020.01-dirty (Jan 08 2020 - 18:05:52 -0200)
>>>
>>> All build on january 8 using the guide I've wrote here
>>> (https://github.com/carlosedp/riscv-bringup/tree/master/unleashed)
>>> after our talks.
>>>
>>> Haven't tested newer versions on Qemu, might build it to give a try. I
>>> have v5.4-rc3 built for Qemu and it works fine.
>>>
>>> Carlos
>>>
>>> On Fri, Jan 31, 2020 at 10:32 AM David Abdurachmanov
>>> <david.abdurachmanov@gmail.com> wrote:
>>>>
>>>> On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
>>>> <me@carlosedp.com> wrote:
>>>>>
>>>>> Golang has been recently upstreamed and I've been building multiple
>>>>> versions on my Unleashed board successfully with kernel 5.3-rc4 and
>>>>> previous.
>>>>>
>>>>> I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
>>>>> Golang doesn't build anymore failing on multiple points and
>>>>> segfaulting as well.
>>>>
>>>> Could you also mention what version of OpenSBI you use?
>>>> Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?
>>>>
>>>>>
>>>>> I've captured a few logs with the error building here:
>>>>>
>>>>> I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
>>>>> out that the commit below is the starting point.
>>>>>
>>>>> eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
>>>>> commit eb93685847a9055283d05951c1b205e737f38533
>>>>> Author: Paul Walmsley <paul.walmsley@sifive.com>
>>>>> Date: Wed Aug 7 19:07:34 2019 -0700
>>>>>
>>>>> riscv: fix flush_tlb_range() end address for flush_tlb_page()
>>>>>
>>>>> The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
>>>>> is set is wrong. It passes zero to flush_tlb_range() as the final
>>>>> address to flush, but it should be at least 'addr'.
>>>>>
>>>>> Some other Linux architecture ports use the beginning address to
>>>>> flush, plus PAGE_SIZE, as the final address to flush. This might
>>>>> flush slightly more than what's needed, but it seems unlikely that
>>>>> being more clever would improve anything. So let's just take that
>>>>> implementation for now.
>>>>>
>>>>> While here, convert the macro into a static inline function, primarily
>>>>> to avoid unintentional multiple evaluations of 'addr'.
>>>>>
>>>>> This second version of the patch fixes a coding style issue found by
>>>>> Christoph Hellwig <hch@lst.de>.
>>>>>
>>>>> Reported-by: Andreas Schwab <schwab@suse.de>
>>>>> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
>>>>> Reviewed-by: Christoph Hellwig <hch@lst.de>
>>>>>
>>>>> :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
>>>>> 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
>>>>>
>>>>>> git bisect visualize
>>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
>>>>> for flush_tlb_page() HEAD, refs/bisect/bad
>>>>>
>>>>>
>>>>>> git diff eb93685^!
>>>>>
>>>>> ```diff
>>>>> diff --git a/arch/riscv/include/asm/tlbflush.h
>>>>> b/arch/riscv/include/asm/tlbflush.h
>>>>> index 687dd19..4d9bbe8 100644
>>>>> --- a/arch/riscv/include/asm/tlbflush.h
>>>>> +++ b/arch/riscv/include/asm/tlbflush.h
>>>>> @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
>>>>> cpumask *cmask, unsigned long start,
>>>>> }
>>>>>
>>>>> #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
>>>>> -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
>>>>> +
>>>>> #define flush_tlb_range(vma, start, end) \
>>>>> remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
>>>>> -#define flush_tlb_mm(mm) \
>>>>> +
>>>>> +static inline void flush_tlb_page(struct vm_area_struct *vma,
>>>>> + unsigned long addr)
>>>>> +{
>>>>> + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
>>>>> +}
>>>>> +
>>>>> +#define flush_tlb_mm(mm) \
>>>>> remote_sfence_vma(mm_cpumask(mm), 0, -1)
>>>>>
>>>>> #endif /* CONFIG_SMP */
>>>>> ```
>>>>>
>>>>> I was not able to revert this change from recent v5.5.0 so I don't
>>>>> know if this is the problem or some close commits:
>>>>>
>>>>>> git log 2b245b8b..2f478b60 |grep riscv
>>>>> 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
>>>>> 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
>>>>> 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
>>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
>>>>> for flush_tlb_page()
>>>>>
>>>>> Carlos
>>>>> --
>>>>> ________________________________________
>>>>> Carlos Eduardo de Paula
>>>>> me@carlosedp.com
>>>>> http://carlosedp.com
>>>>> http://twitter.com/carlosedp
>>>>> Linkedin
>>>>> ________________________________________
>>>>>
>>>>
>>>
>>>
>>> --
>>> ________________________________________
>>> Carlos Eduardo de Paula
>>> me@carlosedp.com
>>> http://carlosedp.com
>>> http://twitter.com/carlosedp
>>> Linkedin
>>> ________________________________________
>>
>>
>>
>> --
>> ________________________________________
>> Carlos Eduardo de Paula
>> me@carlosedp.com
>> http://carlosedp.com
>> http://twitter.com/carlosedp
>> Linkedin
>> ________________________________________
>>
> 
> 



[-- Attachment #2: OpenPGP digital signature --]
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Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Carlos Eduardo de Paula]

Hi Atish, I've added that patch to latest OpenSBI from master, dd'ed
it to my mmcblk0p3 partition but still got problems building Golang
using kernel v5.5.

> export GOROOT_BOOTSTRAP=/home/carlosedp/work/go-linux-riscv64-bootstrap
> time ./make.bash
Building Go cmd/dist using
/home/carlosedp/work/go-linux-riscv64-bootstrap. (devel +a858d15f11 13
hours ago linux/riscv64)
Building Go toolchain1 using /home/carlosedp/work/go-linux-riscv64-bootstrap.
fatal error: stopTheWorld: not stopped (status != _Pgcstop)

runtime stack:
runtime.throw(0x70c63e, 0x2e)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/panic.go:1112
+0x88
runtime.stopTheWorldWithSema()
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/proc.go:971
+0x434
runtime.systemstack(0x5b368)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/asm_riscv64.s:137
+0x80
runtime.mstart()
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/proc.go:1041

goroutine 992 [running]:
runtime.systemstack_switch()
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/asm_riscv64.s:91
+0x8 fp=0x3fb4412f70 sp=0x3fb4412f68 pc=0x909e0
runtime.gcStart(0x0, 0x0, 0x3f00000000)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/mgc.go:1306
+0x2f0 fp=0x3fb4412ff8 sp=0x3fb4412f70 pc=0x33628
runtime.mallocgc(0x40, 0x6367a0, 0x95c78001, 0xeecc28cbf77b49aa)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/malloc.go:1128
+0x4c8 fp=0x3fb4413098 sp=0x3fb4412ff8 pc=0x1e680
runtime.makeslice(0x6367a0, 0x0, 0x40, 0x73d1d8)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/slice.go:49
+0x94 fp=0x3fb44130c0 sp=0x3fb4413098 pc=0x74c2c
strings.(*Builder).grow(...)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/strings/builder.go:68
strings.(*Builder).Grow(...)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/strings/builder.go:82
strings.Join(0x3fb4413200, 0x2, 0x2, 0x6f0656, 0x1, 0x6dc940, 0x3fdd96ee98)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/strings/strings.go:438
+0x460 fp=0x3fb4413190 sp=0x3fb44130c0 pc=0x136fd8
path/filepath.join(0x3fb4413200, 0x2, 0x2, 0x100, 0x50edec)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/path/filepath/path_unix.go:45
+0xe8 fp=0x3fb44131d0 sp=0x3fb4413190 pc=0x145870
path/filepath.Join(...)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/path/filepath/path.go:212
cmd/go/internal/work.mkAbs(0x3fb4554900, 0x38, 0x3fb4404939, 0x7, 0x1,
0x3fb41e6c28)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:2037
+0xb0 fp=0x3fb4413220 sp=0x3fb44131d0 pc=0x502bd8
cmd/go/internal/work.gcToolchain.gc(0x3fb44bfd60, 0x3fb433fcc0,
0x3fb42eee40, 0x23, 0x3fb41201c0, 0xc2, 0x1b8, 0x0, 0x0, 0x3fb42eee00,
...)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/gc.go:139
+0xdd4 fp=0x3fb4413478 sp=0x3fb4413220 pc=0x50ebc4
cmd/go/internal/work.(*gcToolchain).gc(0xbbad10, 0x3fb44bfd60,
0x3fb433fcc0, 0x3fb42eee40, 0x23, 0x3fb41201c0, 0xc2, 0x1b8, 0x0, 0x0,
...)
    <autogenerated>:1 +0xb4 fp=0x3fb4413520 sp=0x3fb4413478 pc=0x5300ac
cmd/go/internal/work.(*Builder).build(0x3fb44bfd60, 0x3fb433fcc0, 0x0, 0x0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:678
+0x169c fp=0x3fb4413e00 sp=0x3fb4413520 pc=0x4f2054
cmd/go/internal/work.(*Builder).Do.func2(0x3fb433fcc0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:118
+0x7c fp=0x3fb4413ed8 sp=0x3fb4413e00 pc=0x52944c
cmd/go/internal/work.(*Builder).Do.func3(0x3fb44a8930, 0x3fb44bfd60,
0x3fb43fe7c0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:178
+0x88 fp=0x3fb4413fc0 sp=0x3fb4413ed8 pc=0x529860
runtime.goexit()
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/asm_riscv64.s:451
+0x4 fp=0x3fb4413fc0 sp=0x3fb4413fc0 pc=0x929e4
created by cmd/go/internal/work.(*Builder).Do
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:165
+0x2d8

goroutine 1 [semacquire]:
sync.runtime_Semacquire(0x3fb44a8938)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/runtime/sema.go:56
+0x4c
sync.(*WaitGroup).Wait(0x3fb44a8930)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/sync/waitgroup.go:130
+0xd4
cmd/go/internal/work.(*Builder).Do(0x3fb44bfd60, 0x3fb438b7c0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:187
+0x300
cmd/go/internal/work.InstallPackages(0x3fb409a090, 0x1, 0x1,
0x3fb40a6e00, 0x3a, 0x40)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/build.go:605
+0x4ac
cmd/go/internal/work.runInstall(0xb87580, 0x3fb409a090, 0x1, 0x1)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/build.go:516
+0x74
main.main()
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/main.go:189
+0x930

goroutine 1121 [select]:
cmd/go/internal/work.(*Builder).Do.func3(0x3fb44a8930, 0x3fb44bfd60,
0x3fb43fe7c0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:168
+0xec
created by cmd/go/internal/work.(*Builder).Do
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:165
+0x2d8

goroutine 991 [select]:
cmd/go/internal/work.(*Builder).Do.func3(0x3fb44a8930, 0x3fb44bfd60,
0x3fb43fe7c0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:168
+0xec
created by cmd/go/internal/work.(*Builder).Do
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:165
+0x2d8

goroutine 990 [runnable]:
syscall.Syscall(0x39, 0xa, 0x0, 0x0, 0x0, 0x0, 0x0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/syscall/asm_linux_riscv64.s:13
+0x14
syscall.Close(0xa, 0x3fb42c2980, 0x10)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/syscall/zsyscall_linux_riscv64.go:285
+0x48
syscall.forkExec(0x3fb42da0a0, 0x4a, 0x3fb42b8a50, 0xf, 0xf,
0x3fb4622ef0, 0xa632444f00010400, 0x3fb4445000, 0x0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/syscall/exec_unix.go:209
+0x348
syscall.StartProcess(...)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/syscall/exec_unix.go:248
os.startProcess(0x3fb42da0a0, 0x4a, 0x3fb42b8a50, 0xf, 0xf,
0x3fb4623088, 0x0, 0x0, 0x0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/os/exec_posix.go:52
+0x1c8
os.StartProcess(0x3fb42da0a0, 0x4a, 0x3fb42b8a50, 0xf, 0xf,
0x3fb4623088, 0x51, 0x0, 0x0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/os/exec.go:102
+0x78
os/exec.(*Cmd).Start(0x3fb42f49a0, 0x3f2d304c58, 0x3d5b8007a8)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/os/exec/exec.go:417
+0x3a4
os/exec.(*Cmd).Run(0x3fb42f49a0, 0x4af513a7c, 0xb91900)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/os/exec/exec.go:337
+0x34
cmd/go/internal/work.(*Builder).runOut(0x3fb44bfd60, 0x3fb433e3c0,
0x3fb41d8460, 0x48, 0x0, 0x0, 0x0, 0x3fb41c6c40, 0x12, 0x1c, ...)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:1928
+0x5bc
cmd/go/internal/work.(*Builder).run(0x3fb44bfd60, 0x3fb433e3c0,
0x3fb41d8460, 0x48, 0x3fb43011e1, 0x14, 0x0, 0x0, 0x0, 0x3fb41c6c40,
...)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:1853
+0x80
cmd/go/internal/work.gcToolchain.symabis.func1(0x3fb44e8900,
0x3fb42a6ed0, 0x1, 0x1, 0x3fb43b1080, 0x23, 0x23, 0x428902ca6305f6ce)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/gc.go:299
+0x2e8
cmd/go/internal/work.gcToolchain.symabis(0x3fb44bfd60, 0x3fb433e3c0,
0x3fb42a6ed0, 0x1, 0x1, 0x2a, 0x40, 0x0, 0x0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/gc.go:306
+0x114
cmd/go/internal/work.(*Builder).build(0x3fb44bfd60, 0x3fb433e3c0, 0x0, 0x0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:642
+0x1208
cmd/go/internal/work.(*Builder).Do.func2(0x3fb433e3c0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:118
+0x7c
cmd/go/internal/work.(*Builder).Do.func3(0x3fb44a8930, 0x3fb44bfd60,
0x3fb43fe7c0)
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:178
+0x88
created by cmd/go/internal/work.(*Builder).Do
    /Users/cdepaula/repos/golang.org/go-linux-riscv64-bootstrap/src/cmd/go/internal/work/exec.go:165
+0x2d8
go tool dist: FAILED:
/home/carlosedp/work/go-linux-riscv64-bootstrap/bin/go install
-gcflags=-l -tags=math_big_pure_go compiler_bootstrap
bootstrap/cmd/...: exit status 2
./make.bash  40.73s user 5.54s system 80% cpu 57.384 total

Did it worked for you William?

Carlos

On Sat, Feb 1, 2020 at 2:08 AM William Grant <me@williamgrant.id.au> wrote:
>
> On 1/2/20 3:58 pm, Atish Patra wrote:
> > On Fri, Jan 31, 2020 at 8:32 AM Carlos Eduardo de Paula
> > <me@carlosedp.com> wrote:
> >>
> >> Updating this issue, I've built the same Golang tree (master) on Qemu
> >> using the same kernel Image v5.5.0 I have on Unleashed and it built
> >> successfully:
> >>
> >> root@qemuriscv:~/go/src# time ./make.bash
> >> Building Go cmd/dist using /root/go-linux-riscv64-bootstrap. (devel
> >> +a858d15f11 13 hours ago linux/riscv64)
> >> Building Go toolchain1 using /root/go-linux-riscv64-bootstrap.
> >> Building Go bootstrap cmd/go (go_bootstrap) using Go toolchain1.
> >> Building Go toolchain2 using go_bootstrap and Go toolchain1.
> >> Building Go toolchain3 using go_bootstrap and Go toolchain2.
> >> Building packages and commands for linux/riscv64.
> >> ---
> >> Installed Go for linux/riscv64 in /root/go
> >> Installed commands in /root/go/bin
> >>
> >> real    43m19.946s
> >> user    120m34.147s
> >> sys    66m34.964s
> >> Linux qemuriscv 5.5.0-dirty #3 SMP Fri Jan 31 00:13:59 -02 2020
> >> riscv64 GNU/Linux
> >> root@qemuriscv:~/go/src# ../bin/go version
> >> go version devel +6e592c2 Fri Jan 31 14:46:05 2020 +0000 linux/riscv64
> >>
> >>
> >> Also tried updating to latest opensbi commit as of today and still
> >> seeing same error on Unleashed.
> >>
> >>
> >
> > Resending it as 1st one did not seem to go through for some reason
> >
> > You might be hitting the tlb flushing hardware errata on unleashed.
> > IIRC, anything other than full tlb flush
> > is broken on unleashed. I don't have the exact errata number or a link
> > that I can point to. May be Paul or somebody else from sifive
> > can share that so that we can document it as well.
> >
> > Can you try this patch in OpenSBI? This forces OpenSBI to do a full
> > flush every time for HiFive Unleashed.
>
> I've separately been trying to track this down for a couple of days, and
> indeed, adjusting OpenSBI to always do a full flush is the easiest
> workaround. I haven't seen any public reference to TLB errata on the
> SoC, but it would explain a lot.
>
> For now I've found that existing kernels with OpenSBI patched to always
> do a full flush, or kernels patched to do a full flush at the end of
> wp_page_copy, get Go building stably. I don't know if there's something
> special about wp_page_copy that tickles the bug, or if it's just called
> often enough that it papers over incomplete flushes elsewhere.
>
> > diff --git a/platform/sifive/fu540/platform.c b/platform/sifive/fu540/platform.c
> > index c8ead9dede23..e36338d2903f 100644
> > --- a/platform/sifive/fu540/platform.c
> > +++ b/platform/sifive/fu540/platform.c
> > @@ -218,5 +218,6 @@ const struct sbi_platform platform = {
> >         .hart_count             = FU540_HART_COUNT,
> >         .hart_stack_size        = FU540_HART_STACK_SIZE,
> >         .disabled_hart_mask     = FU540_HARITD_DISABLED,
> > +       .tlb_range_flush_limit  = 0,
> >         .platform_ops_addr      = (unsigned long)&platform_ops
> >  };
> >
> >> On Fri, Jan 31, 2020 at 11:20 AM Carlos Eduardo de Paula
> >> <me@carlosedp.com> wrote:
> >>>
> >>> My board is running:
> >>>
> >>> SiFive FSBL:       2018-03-20
> >>> OpenSBI v0.5-44-g049ad0b
> >>> U-Boot 2020.01-dirty (Jan 08 2020 - 18:05:52 -0200)
> >>>
> >>> All build on january 8 using the guide I've wrote here
> >>> (https://github.com/carlosedp/riscv-bringup/tree/master/unleashed)
> >>> after our talks.
> >>>
> >>> Haven't tested newer versions on Qemu, might build it to give a try. I
> >>> have v5.4-rc3 built for Qemu and it works fine.
> >>>
> >>> Carlos
> >>>
> >>> On Fri, Jan 31, 2020 at 10:32 AM David Abdurachmanov
> >>> <david.abdurachmanov@gmail.com> wrote:
> >>>>
> >>>> On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
> >>>> <me@carlosedp.com> wrote:
> >>>>>
> >>>>> Golang has been recently upstreamed and I've been building multiple
> >>>>> versions on my Unleashed board successfully with kernel 5.3-rc4 and
> >>>>> previous.
> >>>>>
> >>>>> I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
> >>>>> Golang doesn't build anymore failing on multiple points and
> >>>>> segfaulting as well.
> >>>>
> >>>> Could you also mention what version of OpenSBI you use?
> >>>> Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?
> >>>>
> >>>>>
> >>>>> I've captured a few logs with the error building here:
> >>>>>
> >>>>> I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
> >>>>> out that the commit below is the starting point.
> >>>>>
> >>>>> eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
> >>>>> commit eb93685847a9055283d05951c1b205e737f38533
> >>>>> Author: Paul Walmsley <paul.walmsley@sifive.com>
> >>>>> Date: Wed Aug 7 19:07:34 2019 -0700
> >>>>>
> >>>>> riscv: fix flush_tlb_range() end address for flush_tlb_page()
> >>>>>
> >>>>> The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
> >>>>> is set is wrong. It passes zero to flush_tlb_range() as the final
> >>>>> address to flush, but it should be at least 'addr'.
> >>>>>
> >>>>> Some other Linux architecture ports use the beginning address to
> >>>>> flush, plus PAGE_SIZE, as the final address to flush. This might
> >>>>> flush slightly more than what's needed, but it seems unlikely that
> >>>>> being more clever would improve anything. So let's just take that
> >>>>> implementation for now.
> >>>>>
> >>>>> While here, convert the macro into a static inline function, primarily
> >>>>> to avoid unintentional multiple evaluations of 'addr'.
> >>>>>
> >>>>> This second version of the patch fixes a coding style issue found by
> >>>>> Christoph Hellwig <hch@lst.de>.
> >>>>>
> >>>>> Reported-by: Andreas Schwab <schwab@suse.de>
> >>>>> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
> >>>>> Reviewed-by: Christoph Hellwig <hch@lst.de>
> >>>>>
> >>>>> :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
> >>>>> 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
> >>>>>
> >>>>>> git bisect visualize
> >>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> >>>>> for flush_tlb_page() HEAD, refs/bisect/bad
> >>>>>
> >>>>>
> >>>>>> git diff eb93685^!
> >>>>>
> >>>>> ```diff
> >>>>> diff --git a/arch/riscv/include/asm/tlbflush.h
> >>>>> b/arch/riscv/include/asm/tlbflush.h
> >>>>> index 687dd19..4d9bbe8 100644
> >>>>> --- a/arch/riscv/include/asm/tlbflush.h
> >>>>> +++ b/arch/riscv/include/asm/tlbflush.h
> >>>>> @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
> >>>>> cpumask *cmask, unsigned long start,
> >>>>> }
> >>>>>
> >>>>> #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
> >>>>> -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
> >>>>> +
> >>>>> #define flush_tlb_range(vma, start, end) \
> >>>>> remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
> >>>>> -#define flush_tlb_mm(mm) \
> >>>>> +
> >>>>> +static inline void flush_tlb_page(struct vm_area_struct *vma,
> >>>>> + unsigned long addr)
> >>>>> +{
> >>>>> + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
> >>>>> +}
> >>>>> +
> >>>>> +#define flush_tlb_mm(mm) \
> >>>>> remote_sfence_vma(mm_cpumask(mm), 0, -1)
> >>>>>
> >>>>> #endif /* CONFIG_SMP */
> >>>>> ```
> >>>>>
> >>>>> I was not able to revert this change from recent v5.5.0 so I don't
> >>>>> know if this is the problem or some close commits:
> >>>>>
> >>>>>> git log 2b245b8b..2f478b60 |grep riscv
> >>>>> 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
> >>>>> git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
> >>>>> 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
> >>>>> 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
> >>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> >>>>> for flush_tlb_page()
> >>>>>
> >>>>> Carlos
> >>>>> --
> >>>>> ________________________________________
> >>>>> Carlos Eduardo de Paula
> >>>>> me@carlosedp.com
> >>>>> http://carlosedp.com
> >>>>> http://twitter.com/carlosedp
> >>>>> Linkedin
> >>>>> ________________________________________
> >>>>>
> >>>>
> >>>
> >>>
> >>> --
> >>> ________________________________________
> >>> Carlos Eduardo de Paula
> >>> me@carlosedp.com
> >>> http://carlosedp.com
> >>> http://twitter.com/carlosedp
> >>> Linkedin
> >>> ________________________________________
> >>
> >>
> >>
> >> --
> >> ________________________________________
> >> Carlos Eduardo de Paula
> >> me@carlosedp.com
> >> http://carlosedp.com
> >> http://twitter.com/carlosedp
> >> Linkedin
> >> ________________________________________
> >>
> >
> >
>
>


-- 
________________________________________
Carlos Eduardo de Paula
me@carlosedp.com
http://carlosedp.com
http://twitter.com/carlosedp
Linkedin
________________________________________

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[William Grant]

[-- Attachment #1.1: Type: text/plain, Size: 10125 bytes --]

On 2/2/20 5:58 am, Carlos Eduardo de Paula wrote:
> Hi Atish, I've added that patch to latest OpenSBI from master, dd'ed
> it to my mmcblk0p3 partition but still got problems building Golang
> using kernel v5.5.
> 
> [... snip ...]
> 
> Did it worked for you William?
> 
> Carlos

Ah, sorry, I didn't actually test Atish's patch. It's not quite right,
since .tlb_range_flush_limit = 0 implies the default is used. I think
setting it to 1 should work, but I hadn't noticed the parameter so I'd
just been adjusting sbi_tlb_sfence_vma to have the same bug Linux did:
treat page-size flushes as full ones.

diff --git a/lib/sbi/sbi_tlb.c b/lib/sbi/sbi_tlb.c
index 072915f..165432a 100644
--- a/lib/sbi/sbi_tlb.c
+++ b/lib/sbi/sbi_tlb.c
@@ -70,7 +70,8 @@ static void sbi_tlb_sfence_vma(struct sbi_tlb_info *tinfo)
        unsigned long size  = tinfo->size;
        unsigned long i;

-       if ((start == 0 && size == 0) || (size == SBI_TLB_FLUSH_ALL)) {
+       if ((start == 0 && size == 0) || (size == SBI_TLB_FLUSH_ALL)
+           || (size == PAGE_SIZE)) {
                sbi_tlb_flush_all();
                return;
        }

> On Sat, Feb 1, 2020 at 2:08 AM William Grant <me@williamgrant.id.au> wrote:
>>
>> On 1/2/20 3:58 pm, Atish Patra wrote:
>>> On Fri, Jan 31, 2020 at 8:32 AM Carlos Eduardo de Paula
>>> <me@carlosedp.com> wrote:
>>>>
>>>> Updating this issue, I've built the same Golang tree (master) on Qemu
>>>> using the same kernel Image v5.5.0 I have on Unleashed and it built
>>>> successfully:
>>>>
>>>> root@qemuriscv:~/go/src# time ./make.bash
>>>> Building Go cmd/dist using /root/go-linux-riscv64-bootstrap. (devel
>>>> +a858d15f11 13 hours ago linux/riscv64)
>>>> Building Go toolchain1 using /root/go-linux-riscv64-bootstrap.
>>>> Building Go bootstrap cmd/go (go_bootstrap) using Go toolchain1.
>>>> Building Go toolchain2 using go_bootstrap and Go toolchain1.
>>>> Building Go toolchain3 using go_bootstrap and Go toolchain2.
>>>> Building packages and commands for linux/riscv64.
>>>> ---
>>>> Installed Go for linux/riscv64 in /root/go
>>>> Installed commands in /root/go/bin
>>>>
>>>> real    43m19.946s
>>>> user    120m34.147s
>>>> sys    66m34.964s
>>>> Linux qemuriscv 5.5.0-dirty #3 SMP Fri Jan 31 00:13:59 -02 2020
>>>> riscv64 GNU/Linux
>>>> root@qemuriscv:~/go/src# ../bin/go version
>>>> go version devel +6e592c2 Fri Jan 31 14:46:05 2020 +0000 linux/riscv64
>>>>
>>>>
>>>> Also tried updating to latest opensbi commit as of today and still
>>>> seeing same error on Unleashed.
>>>>
>>>>
>>>
>>> Resending it as 1st one did not seem to go through for some reason
>>>
>>> You might be hitting the tlb flushing hardware errata on unleashed.
>>> IIRC, anything other than full tlb flush
>>> is broken on unleashed. I don't have the exact errata number or a link
>>> that I can point to. May be Paul or somebody else from sifive
>>> can share that so that we can document it as well.
>>>
>>> Can you try this patch in OpenSBI? This forces OpenSBI to do a full
>>> flush every time for HiFive Unleashed.
>>
>> I've separately been trying to track this down for a couple of days, and
>> indeed, adjusting OpenSBI to always do a full flush is the easiest
>> workaround. I haven't seen any public reference to TLB errata on the
>> SoC, but it would explain a lot.
>>
>> For now I've found that existing kernels with OpenSBI patched to always
>> do a full flush, or kernels patched to do a full flush at the end of
>> wp_page_copy, get Go building stably. I don't know if there's something
>> special about wp_page_copy that tickles the bug, or if it's just called
>> often enough that it papers over incomplete flushes elsewhere.
>>
>>> diff --git a/platform/sifive/fu540/platform.c b/platform/sifive/fu540/platform.c
>>> index c8ead9dede23..e36338d2903f 100644
>>> --- a/platform/sifive/fu540/platform.c
>>> +++ b/platform/sifive/fu540/platform.c
>>> @@ -218,5 +218,6 @@ const struct sbi_platform platform = {
>>>         .hart_count             = FU540_HART_COUNT,
>>>         .hart_stack_size        = FU540_HART_STACK_SIZE,
>>>         .disabled_hart_mask     = FU540_HARITD_DISABLED,
>>> +       .tlb_range_flush_limit  = 0,
>>>         .platform_ops_addr      = (unsigned long)&platform_ops
>>>  };
>>>
>>>> On Fri, Jan 31, 2020 at 11:20 AM Carlos Eduardo de Paula
>>>> <me@carlosedp.com> wrote:
>>>>>
>>>>> My board is running:
>>>>>
>>>>> SiFive FSBL:       2018-03-20
>>>>> OpenSBI v0.5-44-g049ad0b
>>>>> U-Boot 2020.01-dirty (Jan 08 2020 - 18:05:52 -0200)
>>>>>
>>>>> All build on january 8 using the guide I've wrote here
>>>>> (https://github.com/carlosedp/riscv-bringup/tree/master/unleashed)
>>>>> after our talks.
>>>>>
>>>>> Haven't tested newer versions on Qemu, might build it to give a try. I
>>>>> have v5.4-rc3 built for Qemu and it works fine.
>>>>>
>>>>> Carlos
>>>>>
>>>>> On Fri, Jan 31, 2020 at 10:32 AM David Abdurachmanov
>>>>> <david.abdurachmanov@gmail.com> wrote:
>>>>>>
>>>>>> On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
>>>>>> <me@carlosedp.com> wrote:
>>>>>>>
>>>>>>> Golang has been recently upstreamed and I've been building multiple
>>>>>>> versions on my Unleashed board successfully with kernel 5.3-rc4 and
>>>>>>> previous.
>>>>>>>
>>>>>>> I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
>>>>>>> Golang doesn't build anymore failing on multiple points and
>>>>>>> segfaulting as well.
>>>>>>
>>>>>> Could you also mention what version of OpenSBI you use?
>>>>>> Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?
>>>>>>
>>>>>>>
>>>>>>> I've captured a few logs with the error building here:
>>>>>>>
>>>>>>> I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
>>>>>>> out that the commit below is the starting point.
>>>>>>>
>>>>>>> eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
>>>>>>> commit eb93685847a9055283d05951c1b205e737f38533
>>>>>>> Author: Paul Walmsley <paul.walmsley@sifive.com>
>>>>>>> Date: Wed Aug 7 19:07:34 2019 -0700
>>>>>>>
>>>>>>> riscv: fix flush_tlb_range() end address for flush_tlb_page()
>>>>>>>
>>>>>>> The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
>>>>>>> is set is wrong. It passes zero to flush_tlb_range() as the final
>>>>>>> address to flush, but it should be at least 'addr'.
>>>>>>>
>>>>>>> Some other Linux architecture ports use the beginning address to
>>>>>>> flush, plus PAGE_SIZE, as the final address to flush. This might
>>>>>>> flush slightly more than what's needed, but it seems unlikely that
>>>>>>> being more clever would improve anything. So let's just take that
>>>>>>> implementation for now.
>>>>>>>
>>>>>>> While here, convert the macro into a static inline function, primarily
>>>>>>> to avoid unintentional multiple evaluations of 'addr'.
>>>>>>>
>>>>>>> This second version of the patch fixes a coding style issue found by
>>>>>>> Christoph Hellwig <hch@lst.de>.
>>>>>>>
>>>>>>> Reported-by: Andreas Schwab <schwab@suse.de>
>>>>>>> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
>>>>>>> Reviewed-by: Christoph Hellwig <hch@lst.de>
>>>>>>>
>>>>>>> :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
>>>>>>> 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
>>>>>>>
>>>>>>>> git bisect visualize
>>>>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
>>>>>>> for flush_tlb_page() HEAD, refs/bisect/bad
>>>>>>>
>>>>>>>
>>>>>>>> git diff eb93685^!
>>>>>>>
>>>>>>> ```diff
>>>>>>> diff --git a/arch/riscv/include/asm/tlbflush.h
>>>>>>> b/arch/riscv/include/asm/tlbflush.h
>>>>>>> index 687dd19..4d9bbe8 100644
>>>>>>> --- a/arch/riscv/include/asm/tlbflush.h
>>>>>>> +++ b/arch/riscv/include/asm/tlbflush.h
>>>>>>> @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
>>>>>>> cpumask *cmask, unsigned long start,
>>>>>>> }
>>>>>>>
>>>>>>> #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
>>>>>>> -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
>>>>>>> +
>>>>>>> #define flush_tlb_range(vma, start, end) \
>>>>>>> remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
>>>>>>> -#define flush_tlb_mm(mm) \
>>>>>>> +
>>>>>>> +static inline void flush_tlb_page(struct vm_area_struct *vma,
>>>>>>> + unsigned long addr)
>>>>>>> +{
>>>>>>> + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
>>>>>>> +}
>>>>>>> +
>>>>>>> +#define flush_tlb_mm(mm) \
>>>>>>> remote_sfence_vma(mm_cpumask(mm), 0, -1)
>>>>>>>
>>>>>>> #endif /* CONFIG_SMP */
>>>>>>> ```
>>>>>>>
>>>>>>> I was not able to revert this change from recent v5.5.0 so I don't
>>>>>>> know if this is the problem or some close commits:
>>>>>>>
>>>>>>>> git log 2b245b8b..2f478b60 |grep riscv
>>>>>>> 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
>>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
>>>>>>> 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
>>>>>>> 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
>>>>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
>>>>>>> for flush_tlb_page()
>>>>>>>
>>>>>>> Carlos
>>>>>>> --
>>>>>>> ________________________________________
>>>>>>> Carlos Eduardo de Paula
>>>>>>> me@carlosedp.com
>>>>>>> http://carlosedp.com
>>>>>>> http://twitter.com/carlosedp
>>>>>>> Linkedin
>>>>>>> ________________________________________
>>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> ________________________________________
>>>>> Carlos Eduardo de Paula
>>>>> me@carlosedp.com
>>>>> http://carlosedp.com
>>>>> http://twitter.com/carlosedp
>>>>> Linkedin
>>>>> ________________________________________
>>>>
>>>>
>>>>
>>>> --
>>>> ________________________________________
>>>> Carlos Eduardo de Paula
>>>> me@carlosedp.com
>>>> http://carlosedp.com
>>>> http://twitter.com/carlosedp
>>>> Linkedin
>>>> ________________________________________
>>>>
>>>
>>>
>>
>>
> 
> 



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Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Atish Patra]

On Sat, Feb 1, 2020 at 3:37 PM William Grant <me@williamgrant.id.au> wrote:
>
> On 2/2/20 5:58 am, Carlos Eduardo de Paula wrote:
> > Hi Atish, I've added that patch to latest OpenSBI from master, dd'ed
> > it to my mmcblk0p3 partition but still got problems building Golang
> > using kernel v5.5.
> >
> > [... snip ...]
> >
> > Did it worked for you William?
> >
> > Carlos
>
> Ah, sorry, I didn't actually test Atish's patch. It's not quite right,
> since .tlb_range_flush_limit = 0 implies the default is used. I think
> setting it to 1 should work,

My bad. That's what happens when you are jet lagged and sent a patch
at 5AM without testing :(.
Ideally, it should be set to zero. I have fixed the issue in platform
header and sent a patch series.

http://lists.infradead.org/pipermail/opensbi/2020-February/001060.html

but I hadn't noticed the parameter so I'd
> just been adjusting sbi_tlb_sfence_vma to have the same bug Linux did:
> treat page-size flushes as full ones.
>
> diff --git a/lib/sbi/sbi_tlb.c b/lib/sbi/sbi_tlb.c
> index 072915f..165432a 100644
> --- a/lib/sbi/sbi_tlb.c
> +++ b/lib/sbi/sbi_tlb.c
> @@ -70,7 +70,8 @@ static void sbi_tlb_sfence_vma(struct sbi_tlb_info *tinfo)
>         unsigned long size  = tinfo->size;
>         unsigned long i;
>
> -       if ((start == 0 && size == 0) || (size == SBI_TLB_FLUSH_ALL)) {
> +       if ((start == 0 && size == 0) || (size == SBI_TLB_FLUSH_ALL)
> +           || (size == PAGE_SIZE)) {
>                 sbi_tlb_flush_all();
>                 return;
>         }
>
> > On Sat, Feb 1, 2020 at 2:08 AM William Grant <me@williamgrant.id.au> wrote:
> >>
> >> On 1/2/20 3:58 pm, Atish Patra wrote:
> >>> On Fri, Jan 31, 2020 at 8:32 AM Carlos Eduardo de Paula
> >>> <me@carlosedp.com> wrote:
> >>>>
> >>>> Updating this issue, I've built the same Golang tree (master) on Qemu
> >>>> using the same kernel Image v5.5.0 I have on Unleashed and it built
> >>>> successfully:
> >>>>
> >>>> root@qemuriscv:~/go/src# time ./make.bash
> >>>> Building Go cmd/dist using /root/go-linux-riscv64-bootstrap. (devel
> >>>> +a858d15f11 13 hours ago linux/riscv64)
> >>>> Building Go toolchain1 using /root/go-linux-riscv64-bootstrap.
> >>>> Building Go bootstrap cmd/go (go_bootstrap) using Go toolchain1.
> >>>> Building Go toolchain2 using go_bootstrap and Go toolchain1.
> >>>> Building Go toolchain3 using go_bootstrap and Go toolchain2.
> >>>> Building packages and commands for linux/riscv64.
> >>>> ---
> >>>> Installed Go for linux/riscv64 in /root/go
> >>>> Installed commands in /root/go/bin
> >>>>
> >>>> real    43m19.946s
> >>>> user    120m34.147s
> >>>> sys    66m34.964s
> >>>> Linux qemuriscv 5.5.0-dirty #3 SMP Fri Jan 31 00:13:59 -02 2020
> >>>> riscv64 GNU/Linux
> >>>> root@qemuriscv:~/go/src# ../bin/go version
> >>>> go version devel +6e592c2 Fri Jan 31 14:46:05 2020 +0000 linux/riscv64
> >>>>
> >>>>
> >>>> Also tried updating to latest opensbi commit as of today and still
> >>>> seeing same error on Unleashed.
> >>>>
> >>>>
> >>>
> >>> Resending it as 1st one did not seem to go through for some reason
> >>>
> >>> You might be hitting the tlb flushing hardware errata on unleashed.
> >>> IIRC, anything other than full tlb flush
> >>> is broken on unleashed. I don't have the exact errata number or a link
> >>> that I can point to. May be Paul or somebody else from sifive
> >>> can share that so that we can document it as well.
> >>>
> >>> Can you try this patch in OpenSBI? This forces OpenSBI to do a full
> >>> flush every time for HiFive Unleashed.
> >>
> >> I've separately been trying to track this down for a couple of days, and
> >> indeed, adjusting OpenSBI to always do a full flush is the easiest
> >> workaround. I haven't seen any public reference to TLB errata on the
> >> SoC, but it would explain a lot.
> >>
> >> For now I've found that existing kernels with OpenSBI patched to always
> >> do a full flush, or kernels patched to do a full flush at the end of
> >> wp_page_copy, get Go building stably. I don't know if there's something
> >> special about wp_page_copy that tickles the bug, or if it's just called
> >> often enough that it papers over incomplete flushes elsewhere.
> >>
> >>> diff --git a/platform/sifive/fu540/platform.c b/platform/sifive/fu540/platform.c
> >>> index c8ead9dede23..e36338d2903f 100644
> >>> --- a/platform/sifive/fu540/platform.c
> >>> +++ b/platform/sifive/fu540/platform.c
> >>> @@ -218,5 +218,6 @@ const struct sbi_platform platform = {
> >>>         .hart_count             = FU540_HART_COUNT,
> >>>         .hart_stack_size        = FU540_HART_STACK_SIZE,
> >>>         .disabled_hart_mask     = FU540_HARITD_DISABLED,
> >>> +       .tlb_range_flush_limit  = 0,
> >>>         .platform_ops_addr      = (unsigned long)&platform_ops
> >>>  };
> >>>
> >>>> On Fri, Jan 31, 2020 at 11:20 AM Carlos Eduardo de Paula
> >>>> <me@carlosedp.com> wrote:
> >>>>>
> >>>>> My board is running:
> >>>>>
> >>>>> SiFive FSBL:       2018-03-20
> >>>>> OpenSBI v0.5-44-g049ad0b
> >>>>> U-Boot 2020.01-dirty (Jan 08 2020 - 18:05:52 -0200)
> >>>>>
> >>>>> All build on january 8 using the guide I've wrote here
> >>>>> (https://github.com/carlosedp/riscv-bringup/tree/master/unleashed)
> >>>>> after our talks.
> >>>>>
> >>>>> Haven't tested newer versions on Qemu, might build it to give a try. I
> >>>>> have v5.4-rc3 built for Qemu and it works fine.
> >>>>>
> >>>>> Carlos
> >>>>>
> >>>>> On Fri, Jan 31, 2020 at 10:32 AM David Abdurachmanov
> >>>>> <david.abdurachmanov@gmail.com> wrote:
> >>>>>>
> >>>>>> On Fri, Jan 31, 2020 at 2:14 PM Carlos Eduardo de Paula
> >>>>>> <me@carlosedp.com> wrote:
> >>>>>>>
> >>>>>>> Golang has been recently upstreamed and I've been building multiple
> >>>>>>> versions on my Unleashed board successfully with kernel 5.3-rc4 and
> >>>>>>> previous.
> >>>>>>>
> >>>>>>> I noticed that after I updated my Kernel from v5.3-rc4 to v5.5-rc5,
> >>>>>>> Golang doesn't build anymore failing on multiple points and
> >>>>>>> segfaulting as well.
> >>>>>>
> >>>>>> Could you also mention what version of OpenSBI you use?
> >>>>>> Does it also fail on QEMU (avoid 4.2.0) or only on Unleashed?
> >>>>>>
> >>>>>>>
> >>>>>>> I've captured a few logs with the error building here:
> >>>>>>>
> >>>>>>> I've bisected the versions between v5.4-rc3 and v5.4 and it pointed
> >>>>>>> out that the commit below is the starting point.
> >>>>>>>
> >>>>>>> eb93685847a9055283d05951c1b205e737f38533 is the first bad commit
> >>>>>>> commit eb93685847a9055283d05951c1b205e737f38533
> >>>>>>> Author: Paul Walmsley <paul.walmsley@sifive.com>
> >>>>>>> Date: Wed Aug 7 19:07:34 2019 -0700
> >>>>>>>
> >>>>>>> riscv: fix flush_tlb_range() end address for flush_tlb_page()
> >>>>>>>
> >>>>>>> The RISC-V kernel implementation of flush_tlb_page() when CONFIG_SMP
> >>>>>>> is set is wrong. It passes zero to flush_tlb_range() as the final
> >>>>>>> address to flush, but it should be at least 'addr'.
> >>>>>>>
> >>>>>>> Some other Linux architecture ports use the beginning address to
> >>>>>>> flush, plus PAGE_SIZE, as the final address to flush. This might
> >>>>>>> flush slightly more than what's needed, but it seems unlikely that
> >>>>>>> being more clever would improve anything. So let's just take that
> >>>>>>> implementation for now.
> >>>>>>>
> >>>>>>> While here, convert the macro into a static inline function, primarily
> >>>>>>> to avoid unintentional multiple evaluations of 'addr'.
> >>>>>>>
> >>>>>>> This second version of the patch fixes a coding style issue found by
> >>>>>>> Christoph Hellwig <hch@lst.de>.
> >>>>>>>
> >>>>>>> Reported-by: Andreas Schwab <schwab@suse.de>
> >>>>>>> Signed-off-by: Paul Walmsley <paul.walmsley@sifive.com>
> >>>>>>> Reviewed-by: Christoph Hellwig <hch@lst.de>
> >>>>>>>
> >>>>>>> :040000 040000 1a4ee20b3614c93de2a925bba2df6f2e1518f227
> >>>>>>> 6b4ffd3e1a2245912cf734a8a3f61db7eb0ccd67 M arch
> >>>>>>>
> >>>>>>>> git bisect visualize
> >>>>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> >>>>>>> for flush_tlb_page() HEAD, refs/bisect/bad
> >>>>>>>
> >>>>>>>
> >>>>>>>> git diff eb93685^!
> >>>>>>>
> >>>>>>> ```diff
> >>>>>>> diff --git a/arch/riscv/include/asm/tlbflush.h
> >>>>>>> b/arch/riscv/include/asm/tlbflush.h
> >>>>>>> index 687dd19..4d9bbe8 100644
> >>>>>>> --- a/arch/riscv/include/asm/tlbflush.h
> >>>>>>> +++ b/arch/riscv/include/asm/tlbflush.h
> >>>>>>> @@ -53,10 +53,17 @@ static inline void remote_sfence_vma(struct
> >>>>>>> cpumask *cmask, unsigned long start,
> >>>>>>> }
> >>>>>>>
> >>>>>>> #define flush_tlb_all() sbi_remote_sfence_vma(NULL, 0, -1)
> >>>>>>> -#define flush_tlb_page(vma, addr) flush_tlb_range(vma, addr, 0)
> >>>>>>> +
> >>>>>>> #define flush_tlb_range(vma, start, end) \
> >>>>>>> remote_sfence_vma(mm_cpumask((vma)->vm_mm), start, (end) - (start))
> >>>>>>> -#define flush_tlb_mm(mm) \
> >>>>>>> +
> >>>>>>> +static inline void flush_tlb_page(struct vm_area_struct *vma,
> >>>>>>> + unsigned long addr)
> >>>>>>> +{
> >>>>>>> + flush_tlb_range(vma, addr, addr + PAGE_SIZE);
> >>>>>>> +}
> >>>>>>> +
> >>>>>>> +#define flush_tlb_mm(mm) \
> >>>>>>> remote_sfence_vma(mm_cpumask(mm), 0, -1)
> >>>>>>>
> >>>>>>> #endif /* CONFIG_SMP */
> >>>>>>> ```
> >>>>>>>
> >>>>>>> I was not able to revert this change from recent v5.5.0 so I don't
> >>>>>>> know if this is the problem or some close commits:
> >>>>>>>
> >>>>>>>> git log 2b245b8b..2f478b60 |grep riscv
> >>>>>>> 2f478b6 N 6 months ago Linus..Merge tag 'riscv/for-v5.3-rc5' of
> >>>>>>> git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
> >>>>>>> 69703eb N 6 months ago Vince..riscv: Make __fstate_clean() work correctly.
> >>>>>>> 8ac71d7 N 6 months ago Vince..riscv: Correct the initialized flow of FP register
> >>>>>>> eb93685 N 6 months ago Paul ..riscv: fix flush_tlb_range() end address
> >>>>>>> for flush_tlb_page()
> >>>>>>>
> >>>>>>> Carlos
> >>>>>>> --
> >>>>>>> ________________________________________
> >>>>>>> Carlos Eduardo de Paula
> >>>>>>> me@carlosedp.com
> >>>>>>> http://carlosedp.com
> >>>>>>> http://twitter.com/carlosedp
> >>>>>>> Linkedin
> >>>>>>> ________________________________________
> >>>>>>>
> >>>>>>
> >>>>>
> >>>>>
> >>>>> --
> >>>>> ________________________________________
> >>>>> Carlos Eduardo de Paula
> >>>>> me@carlosedp.com
> >>>>> http://carlosedp.com
> >>>>> http://twitter.com/carlosedp
> >>>>> Linkedin
> >>>>> ________________________________________
> >>>>
> >>>>
> >>>>
> >>>> --
> >>>> ________________________________________
> >>>> Carlos Eduardo de Paula
> >>>> me@carlosedp.com
> >>>> http://carlosedp.com
> >>>> http://twitter.com/carlosedp
> >>>> Linkedin
> >>>> ________________________________________
> >>>>
> >>>
> >>>
> >>
> >>
> >
> >
>
>


-- 
Regards,
Atish

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Carlos Eduardo de Paula]

On Sun, Feb 2, 2020 at 9:30 AM Atish Patra <atishp@atishpatra.org> wrote:
>
> On Sat, Feb 1, 2020 at 3:37 PM William Grant <me@williamgrant.id.au> wrote:
> >
> > On 2/2/20 5:58 am, Carlos Eduardo de Paula wrote:
> > > Hi Atish, I've added that patch to latest OpenSBI from master, dd'ed
> > > it to my mmcblk0p3 partition but still got problems building Golang
> > > using kernel v5.5.
> > >
> > > [... snip ...]
> > >
> > > Did it worked for you William?
> > >
> > > Carlos
> >
> > Ah, sorry, I didn't actually test Atish's patch. It's not quite right,
> > since .tlb_range_flush_limit = 0 implies the default is used. I think
> > setting it to 1 should work,
>
> My bad. That's what happens when you are jet lagged and sent a patch
> at 5AM without testing :(.
> Ideally, it should be set to zero. I have fixed the issue in platform
> header and sent a patch series.
>
> http://lists.infradead.org/pipermail/opensbi/2020-February/001060.html
>
> --
> Regards,
> Atish


No worries Atish :)

I've changed the parameter to "1" and confirm that it works.

Built and tested Golang on v5.5.
Carlos

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Paul Walmsley]

Hi folks, sorry for the late response.

On Fri, 31 Jan 2020, Atish Patra wrote:

> You might be hitting the tlb flushing hardware errata on unleashed. 
> IIRC, anything other than full tlb flush is broken on unleashed. I don't 
> have the exact errata number or a link that I can point to. May be Paul 
> or somebody else from sifive can share that so that we can document it 
> as well.

This is correct: full TLB flushes are required on HiFive Unleashed, even 
for smaller ranges.  SiFive hasn't officially published the erratum yet.  
This is probably the closest thing to it that is currently public:

https://github.com/chipsalliance/rocket-chip/commit/592fe534fb8d7243a7ba636a4577c7b018ee131b


- Paul

Re: Errors and segmentation fault while building Golang on Kernel after v5.4-rc3

[Carlos Eduardo de Paula]

Just build OpenSBI v0.6 and Kernel 5.6-rc5 and I can confirm it works fine.

I didn't see the TLB problems as before.

Thanks!

On Wed, Mar 11, 2020 at 1:29 PM David Abdurachmanov
<david.abdurachmanov@sifive.com> wrote:
>
> On Wed, Mar 11, 2020 at 8:38 AM Carlos Eduardo de Paula
> <me@carlosedp.com> wrote:
> >
> > On Mon, Feb 3, 2020 at 12:06 PM Carlos Eduardo de Paula
> > <me@carlosedp.com> wrote:
> > >
> > > On Sun, Feb 2, 2020 at 9:30 AM Atish Patra <atishp@atishpatra.org> wrote:
> > > >
> > > > On Sat, Feb 1, 2020 at 3:37 PM William Grant <me@williamgrant.id.au> wrote:
> > > > >
> > > > > On 2/2/20 5:58 am, Carlos Eduardo de Paula wrote:
> > > > > > Hi Atish, I've added that patch to latest OpenSBI from master, dd'ed
> > > > > > it to my mmcblk0p3 partition but still got problems building Golang
> > > > > > using kernel v5.5.
> > > > > >
> > > > > > [... snip ...]
> > > > > >
> > > > > > Did it worked for you William?
> > > > > >
> > > > > > Carlos
> > > > >
> > > > > Ah, sorry, I didn't actually test Atish's patch. It's not quite right,
> > > > > since .tlb_range_flush_limit = 0 implies the default is used. I think
> > > > > setting it to 1 should work,
> > > >
> > > > My bad. That's what happens when you are jet lagged and sent a patch
> > > > at 5AM without testing :(.
> > > > Ideally, it should be set to zero. I have fixed the issue in platform
> > > > header and sent a patch series.
> > > >
> > > > http://lists.infradead.org/pipermail/opensbi/2020-February/001060.html
> > > >
> > > > --
> > > > Regards,
> > > > Atish
> > >
> > >
> > > No worries Atish :)
> > >
> > > I've changed the parameter to "1" and confirm that it works.
> > >
> > > Built and tested Golang on v5.5.
> > > Carlos
> >
> > Atish, the correction of the TLB flush sent previously will be
> > upstreamed into OpenSBI or is something that should be patched
> > off-tree?
>
> This was merged sometime ago and is available in v0.6.
>
> david



-- 
________________________________________
Carlos Eduardo de Paula
me@carlosedp.com
http://carlosedp.com
https://twitter.com/carlosedp
https://www.linkedin.com/in/carlosedp/
________________________________________