[PATCH] xen/arm64: do not (incorrectly) limit size of xenheap

[PATCH] xen/arm64: do not (incorrectly) limit size of xenheap

[Julien Grall]

The commit 88e3ed61642bb393458acc7a9bd2f96edc337190 "x86/NUMA: make
init_node_heap() respect Xen heap limit" breaks boot on the arm64 board
X-Gene.

The xenheap bits variable is used to know the last RAM MFN always mapped
in Xen virtual memory. If the value is 0, it means that all the memory is
always mapped in Xen virtual memory.

On X-gene the RAM bank resides above 128GB and last xenheap MFN is
0x4400000. With the new way to calculate the number of bits, xenheap_bits
will be equal to 38 bits. This will result to hide all the RAM and the
impossibility to allocate xenheap memory.

Given that aarch64 have always all the memory mapped in Xen virtual
memory, it's not necessary to call xenheap_max_mfn which set the number
of bits.

Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Julien Grall <julien.grall@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

---
    Changes in v2:
        - Update the commit title
        - Add Ian's acked
---
 xen/arch/arm/setup.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 6626eba..48f734f 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -665,7 +665,6 @@ static void __init setup_mm(unsigned long dtb_paddr, size_t dtb_size)
     xenheap_virt_end = XENHEAP_VIRT_START + ram_end - ram_start;
     xenheap_mfn_start = ram_start >> PAGE_SHIFT;
     xenheap_mfn_end = ram_end >> PAGE_SHIFT;
-    xenheap_max_mfn(xenheap_mfn_end);
 
     /*
      * Need enough mapped pages for copying the DTB.
-- 
2.1.4

Re: [PATCH] xen/arm64: do not (incorrectly) limit size of xenheap

[Wei Liu]

On Fri, Sep 04, 2015 at 01:57:00PM +0100, Julien Grall wrote:
> The commit 88e3ed61642bb393458acc7a9bd2f96edc337190 "x86/NUMA: make
> init_node_heap() respect Xen heap limit" breaks boot on the arm64 board
> X-Gene.
> 
> The xenheap bits variable is used to know the last RAM MFN always mapped
> in Xen virtual memory. If the value is 0, it means that all the memory is
> always mapped in Xen virtual memory.
> 
> On X-gene the RAM bank resides above 128GB and last xenheap MFN is
> 0x4400000. With the new way to calculate the number of bits, xenheap_bits
> will be equal to 38 bits. This will result to hide all the RAM and the
> impossibility to allocate xenheap memory.
> 
> Given that aarch64 have always all the memory mapped in Xen virtual
> memory, it's not necessary to call xenheap_max_mfn which set the number
> of bits.
> 
> Suggested-by: Jan Beulich <jbeulich@suse.com>
> Signed-off-by: Julien Grall <julien.grall@citrix.com>
> Acked-by: Ian Campbell <ian.campbell@citrix.com>
> 

Release-acked-by: Wei Liu <wei.liu2@citrix.com>

Re: [PATCH] xen/arm64: do not (incorrectly) limit size of xenheap

[Ian Campbell]

On Fri, 2015-09-04 at 14:16 +0100, Wei Liu wrote:
> On Fri, Sep 04, 2015 at 01:57:00PM +0100, Julien Grall wrote:
> > The commit 88e3ed61642bb393458acc7a9bd2f96edc337190 "x86/NUMA: make
> > init_node_heap() respect Xen heap limit" breaks boot on the arm64 board
> > X-Gene.
> > 
> > The xenheap bits variable is used to know the last RAM MFN always 
> > mapped
> > in Xen virtual memory. If the value is 0, it means that all the memory 
> > is
> > always mapped in Xen virtual memory.
> > 
> > On X-gene the RAM bank resides above 128GB and last xenheap MFN is
> > 0x4400000. With the new way to calculate the number of bits, 
> > xenheap_bits
> > will be equal to 38 bits. This will result to hide all the RAM and the
> > impossibility to allocate xenheap memory.
> > 
> > Given that aarch64 have always all the memory mapped in Xen virtual
> > memory, it's not necessary to call xenheap_max_mfn which set the number
> > of bits.
> > 
> > Suggested-by: Jan Beulich <jbeulich@suse.com>
> > Signed-off-by: Julien Grall <julien.grall@citrix.com>
> > Acked-by: Ian Campbell <ian.campbell@citrix.com>
> > 
> 
> Release-acked-by: Wei Liu <wei.liu2@citrix.com>

Applied.