Re: [PATCH] openrisc: Reserve memblock for initrd

2020-09-03 Thread Stafford Horne
On Tue, Sep 01, 2020 at 03:11:30PM +0300, Mike Rapoport wrote:
> On Tue, Sep 01, 2020 at 07:20:44PM +0900, Stafford Horne wrote:
> > On Tue, Sep 01, 2020 at 08:59:24AM +0300, Mike Rapoport wrote:
> > > On Tue, Sep 01, 2020 at 06:21:01AM +0900, Stafford Horne wrote:
> > > > Recently OpenRISC added support for external initrd images, but I found
> > > > some instability when using larger buildroot initrd images. It turned
> > > > out that I forgot to reserve the memblock space for the initrd image.
> > > > 
> > > > This patch fixes the instability issue by reserving memblock space.
> > > > 
> > > > Fixes: ff6c923dbec3 ("openrisc: Add support for external initrd images")
> > > > Signed-off-by: Stafford Horne 
> > > > ---
> > > >  arch/openrisc/kernel/setup.c | 9 +
> > > >  1 file changed, 9 insertions(+)
> > > > 
> > > > diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c
> > > > index b18e775f8be3..2c8aa53cc7ba 100644
> > > > --- a/arch/openrisc/kernel/setup.c
> > > > +++ b/arch/openrisc/kernel/setup.c
> > > > @@ -80,6 +80,15 @@ static void __init setup_memory(void)
> > > >  */
> > > > memblock_reserve(__pa(_stext), _end - _stext);
> > > >  
> > > > +#ifdef CONFIG_BLK_DEV_INITRD
> > > > +   /* Then reserve the initrd, if any */
> > > > +   if (initrd_start && (initrd_end > initrd_start)) {
> > > > +   memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
> > > > +   ALIGN(initrd_end, PAGE_SIZE) -
> > > > +   ALIGN_DOWN(initrd_start, PAGE_SIZE));
> > > > +   }
> > > 
> > > The core mm takes care of reserving the entrire pages for the memory
> > > reserved with memblock, so it is not necessary to do it here.
> > 
> > Thanks for the pointer
> > 
> > I guess what you mean is it is not required to do the page alignment.
> 
> Right. 
> 
> > I used other architectures as an example and most do the alignment, I
> > think for most architectures this can be pulled out to generic code.
> 
> You are more than welcome :)
> We already have a generic free_initrd_mem(), maybe it's time to have a
> generic reserve_initrd_mem().
> 
> I'm ok with openrisc doing the alignment, but I think using local
> variables would make the core more readable, e.g
> 
>   if (initd_start && (initrd_end)) {
>   unsigned long aligned_start = ALIGN_DOWN(initrd_start, 
> PAGE_SIZE);
>   unsigned long aligned_end = ALIGN(end, PAGE_SIZE);
> 
>   memblock_reserve(aligned_start, aligned_end);
>   }
> 
> What do you say?

Well, if the alignment is not needed I rather not do it.  That would make the
code as simple as:

if (initrd_start && (initrd_end > initrd_start)) {
memblock_reserve(__pa(initrd_start), initrd_end - initrd_start);
}

Let me look what is involved in making a reserve_initrd_mem().

-Stafford

> > -Stafford
> > 
> > > > +#endif /* CONFIG_BLK_DEV_INITRD */
> > > > +
> > > > early_init_fdt_reserve_self();
> > > > early_init_fdt_scan_reserved_mem();
> > > >  
> > > > -- 
> > > > 2.26.2
> > > > 
> > > 
> > > -- 
> > > Sincerely yours,
> > > Mike.
> 
> -- 
> Sincerely yours,
> Mike.


Re: [PATCH] openrisc: Reserve memblock for initrd

2020-09-01 Thread Mike Rapoport
On Tue, Sep 01, 2020 at 07:20:44PM +0900, Stafford Horne wrote:
> On Tue, Sep 01, 2020 at 08:59:24AM +0300, Mike Rapoport wrote:
> > On Tue, Sep 01, 2020 at 06:21:01AM +0900, Stafford Horne wrote:
> > > Recently OpenRISC added support for external initrd images, but I found
> > > some instability when using larger buildroot initrd images. It turned
> > > out that I forgot to reserve the memblock space for the initrd image.
> > > 
> > > This patch fixes the instability issue by reserving memblock space.
> > > 
> > > Fixes: ff6c923dbec3 ("openrisc: Add support for external initrd images")
> > > Signed-off-by: Stafford Horne 
> > > ---
> > >  arch/openrisc/kernel/setup.c | 9 +
> > >  1 file changed, 9 insertions(+)
> > > 
> > > diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c
> > > index b18e775f8be3..2c8aa53cc7ba 100644
> > > --- a/arch/openrisc/kernel/setup.c
> > > +++ b/arch/openrisc/kernel/setup.c
> > > @@ -80,6 +80,15 @@ static void __init setup_memory(void)
> > >*/
> > >   memblock_reserve(__pa(_stext), _end - _stext);
> > >  
> > > +#ifdef CONFIG_BLK_DEV_INITRD
> > > + /* Then reserve the initrd, if any */
> > > + if (initrd_start && (initrd_end > initrd_start)) {
> > > + memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
> > > + ALIGN(initrd_end, PAGE_SIZE) -
> > > + ALIGN_DOWN(initrd_start, PAGE_SIZE));
> > > + }
> > 
> > The core mm takes care of reserving the entrire pages for the memory
> > reserved with memblock, so it is not necessary to do it here.
> 
> Thanks for the pointer
> 
> I guess what you mean is it is not required to do the page alignment.

Right. 

> I used other architectures as an example and most do the alignment, I
> think for most architectures this can be pulled out to generic code.

You are more than welcome :)
We already have a generic free_initrd_mem(), maybe it's time to have a
generic reserve_initrd_mem().

I'm ok with openrisc doing the alignment, but I think using local
variables would make the core more readable, e.g

if (initd_start && (initrd_end)) {
unsigned long aligned_start = ALIGN_DOWN(initrd_start, 
PAGE_SIZE);
unsigned long aligned_end = ALIGN(end, PAGE_SIZE);

memblock_reserve(aligned_start, aligned_end);
}

What do you say?

> -Stafford
> 
> > > +#endif /* CONFIG_BLK_DEV_INITRD */
> > > +
> > >   early_init_fdt_reserve_self();
> > >   early_init_fdt_scan_reserved_mem();
> > >  
> > > -- 
> > > 2.26.2
> > > 
> > 
> > -- 
> > Sincerely yours,
> > Mike.

-- 
Sincerely yours,
Mike.


Re: [PATCH] openrisc: Reserve memblock for initrd

2020-09-01 Thread Stafford Horne
On Tue, Sep 01, 2020 at 08:59:24AM +0300, Mike Rapoport wrote:
> On Tue, Sep 01, 2020 at 06:21:01AM +0900, Stafford Horne wrote:
> > Recently OpenRISC added support for external initrd images, but I found
> > some instability when using larger buildroot initrd images. It turned
> > out that I forgot to reserve the memblock space for the initrd image.
> > 
> > This patch fixes the instability issue by reserving memblock space.
> > 
> > Fixes: ff6c923dbec3 ("openrisc: Add support for external initrd images")
> > Signed-off-by: Stafford Horne 
> > ---
> >  arch/openrisc/kernel/setup.c | 9 +
> >  1 file changed, 9 insertions(+)
> > 
> > diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c
> > index b18e775f8be3..2c8aa53cc7ba 100644
> > --- a/arch/openrisc/kernel/setup.c
> > +++ b/arch/openrisc/kernel/setup.c
> > @@ -80,6 +80,15 @@ static void __init setup_memory(void)
> >  */
> > memblock_reserve(__pa(_stext), _end - _stext);
> >  
> > +#ifdef CONFIG_BLK_DEV_INITRD
> > +   /* Then reserve the initrd, if any */
> > +   if (initrd_start && (initrd_end > initrd_start)) {
> > +   memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
> > +   ALIGN(initrd_end, PAGE_SIZE) -
> > +   ALIGN_DOWN(initrd_start, PAGE_SIZE));
> > +   }
> 
> The core mm takes care of reserving the entrire pages for the memory
> reserved with memblock, so it is not necessary to do it here.

Thanks for the pointer

I guess what you mean is it is not required to do the page alignment.  I used
other architectures as an example and most do the alignment, I think for most
architectures this can be pulled out to generic code.

-Stafford

> > +#endif /* CONFIG_BLK_DEV_INITRD */
> > +
> > early_init_fdt_reserve_self();
> > early_init_fdt_scan_reserved_mem();
> >  
> > -- 
> > 2.26.2
> > 
> 
> -- 
> Sincerely yours,
> Mike.


Re: [PATCH] openrisc: Reserve memblock for initrd

2020-08-31 Thread Mike Rapoport
On Tue, Sep 01, 2020 at 06:21:01AM +0900, Stafford Horne wrote:
> Recently OpenRISC added support for external initrd images, but I found
> some instability when using larger buildroot initrd images. It turned
> out that I forgot to reserve the memblock space for the initrd image.
> 
> This patch fixes the instability issue by reserving memblock space.
> 
> Fixes: ff6c923dbec3 ("openrisc: Add support for external initrd images")
> Signed-off-by: Stafford Horne 
> ---
>  arch/openrisc/kernel/setup.c | 9 +
>  1 file changed, 9 insertions(+)
> 
> diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c
> index b18e775f8be3..2c8aa53cc7ba 100644
> --- a/arch/openrisc/kernel/setup.c
> +++ b/arch/openrisc/kernel/setup.c
> @@ -80,6 +80,15 @@ static void __init setup_memory(void)
>*/
>   memblock_reserve(__pa(_stext), _end - _stext);
>  
> +#ifdef CONFIG_BLK_DEV_INITRD
> + /* Then reserve the initrd, if any */
> + if (initrd_start && (initrd_end > initrd_start)) {
> + memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
> + ALIGN(initrd_end, PAGE_SIZE) -
> + ALIGN_DOWN(initrd_start, PAGE_SIZE));
> + }

The core mm takes care of reserving the entrire pages for the memory
reserved with memblock, so it is not necessary to do it here.

> +#endif /* CONFIG_BLK_DEV_INITRD */
> +
>   early_init_fdt_reserve_self();
>   early_init_fdt_scan_reserved_mem();
>  
> -- 
> 2.26.2
> 

-- 
Sincerely yours,
Mike.


[PATCH] openrisc: Reserve memblock for initrd

2020-08-31 Thread Stafford Horne
Recently OpenRISC added support for external initrd images, but I found
some instability when using larger buildroot initrd images. It turned
out that I forgot to reserve the memblock space for the initrd image.

This patch fixes the instability issue by reserving memblock space.

Fixes: ff6c923dbec3 ("openrisc: Add support for external initrd images")
Signed-off-by: Stafford Horne 
---
 arch/openrisc/kernel/setup.c | 9 +
 1 file changed, 9 insertions(+)

diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c
index b18e775f8be3..2c8aa53cc7ba 100644
--- a/arch/openrisc/kernel/setup.c
+++ b/arch/openrisc/kernel/setup.c
@@ -80,6 +80,15 @@ static void __init setup_memory(void)
 */
memblock_reserve(__pa(_stext), _end - _stext);
 
+#ifdef CONFIG_BLK_DEV_INITRD
+   /* Then reserve the initrd, if any */
+   if (initrd_start && (initrd_end > initrd_start)) {
+   memblock_reserve(ALIGN_DOWN(__pa(initrd_start), PAGE_SIZE),
+   ALIGN(initrd_end, PAGE_SIZE) -
+   ALIGN_DOWN(initrd_start, PAGE_SIZE));
+   }
+#endif /* CONFIG_BLK_DEV_INITRD */
+
early_init_fdt_reserve_self();
early_init_fdt_scan_reserved_mem();
 
-- 
2.26.2