[v2,06/21] memblock: memblock_phys_alloc_try_nid(): don't panic

[v2,06/21] memblock: memblock_phys_alloc_try_nid(): don't panic

[Michael Ellerman]

Michael Ellerman <mpe@ellerman.id.au> writes:

> Mike Rapoport <rppt@linux.ibm.com> writes:
>
>> diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
>> index ae34e3a..2c61ea4 100644
>> --- a/arch/arm64/mm/numa.c
>> +++ b/arch/arm64/mm/numa.c
>> @@ -237,6 +237,10 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
>>  		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
>>  
>>  	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
>> +	if (!nd_pa)
>> +		panic("Cannot allocate %zu bytes for node %d data\n",
>> +		      nd_size, nid);
>> +
>>  	nd = __va(nd_pa);

Wrong hunk, O_o

> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

You know what I mean though :)

cheers

[v2,06/21] memblock: memblock_phys_alloc_try_nid(): don't panic

[Michael Ellerman]

Mike Rapoport <rppt@linux.ibm.com> writes:

> diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
> index ae34e3a..2c61ea4 100644
> --- a/arch/arm64/mm/numa.c
> +++ b/arch/arm64/mm/numa.c
> @@ -237,6 +237,10 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
>  		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
>  
>  	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
> +	if (!nd_pa)
> +		panic("Cannot allocate %zu bytes for node %d data\n",
> +		      nd_size, nid);
> +
>  	nd = __va(nd_pa);

Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)

cheers

[v2,06/21] memblock: memblock_phys_alloc_try_nid(): don't panic

[Mike Rapoport]

On Fri, Jan 25, 2019 at 05:45:02PM +0000, Catalin Marinas wrote:
> On Mon, Jan 21, 2019 at 10:03:53AM +0200, Mike Rapoport wrote:
> > diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
> > index ae34e3a..2c61ea4 100644
> > --- a/arch/arm64/mm/numa.c
> > +++ b/arch/arm64/mm/numa.c
> > @@ -237,6 +237,10 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
> >  		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
> >  
> >  	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
> > +	if (!nd_pa)
> > +		panic("Cannot allocate %zu bytes for node %d data\n",
> > +		      nd_size, nid);
> > +
> >  	nd = __va(nd_pa);
> >  
> >  	/* report and initialize */
> 
> Does it mean that memblock_phys_alloc_try_nid() never returns valid
> physical memory starting at 0?

Yes, it does.
memblock_find_in_range_node() that is used by all allocation methods
skips the first page [1].
 
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/mm/memblock.c#n257

> -- 
> Catalin
>

[v2,06/21] memblock: memblock_phys_alloc_try_nid(): don't panic

[Catalin Marinas]

On Mon, Jan 21, 2019 at 10:03:53AM +0200, Mike Rapoport wrote:
> diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
> index ae34e3a..2c61ea4 100644
> --- a/arch/arm64/mm/numa.c
> +++ b/arch/arm64/mm/numa.c
> @@ -237,6 +237,10 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
>  		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
>  
>  	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
> +	if (!nd_pa)
> +		panic("Cannot allocate %zu bytes for node %d data\n",
> +		      nd_size, nid);
> +
>  	nd = __va(nd_pa);
>  
>  	/* report and initialize */

Does it mean that memblock_phys_alloc_try_nid() never returns valid
physical memory starting at 0?

[v2,06/21] memblock: memblock_phys_alloc_try_nid(): don't panic

[Mike Rapoport]

The memblock_phys_alloc_try_nid() function tries to allocate memory from
the requested node and then falls back to allocation from any node in the
system. The memblock_alloc_base() fallback used by this function panics if
the allocation fails.

Replace the memblock_alloc_base() fallback with the direct call to
memblock_alloc_range_nid() and update the memblock_phys_alloc_try_nid()
callers to check the returned value and panic in case of error.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
---
 arch/arm64/mm/numa.c   | 4 ++++
 arch/powerpc/mm/numa.c | 4 ++++
 mm/memblock.c          | 4 +++-
 3 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
index ae34e3a..2c61ea4 100644
--- a/arch/arm64/mm/numa.c
+++ b/arch/arm64/mm/numa.c
@@ -237,6 +237,10 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
 		pr_info("Initmem setup node %d [<memory-less node>]\n", nid);
 
 	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
+	if (!nd_pa)
+		panic("Cannot allocate %zu bytes for node %d data\n",
+		      nd_size, nid);
+
 	nd = __va(nd_pa);
 
 	/* report and initialize */
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 270cefb..8f2bbe1 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -788,6 +788,10 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
 	int tnid;
 
 	nd_pa = memblock_phys_alloc_try_nid(nd_size, SMP_CACHE_BYTES, nid);
+	if (!nd_pa)
+		panic("Cannot allocate %zu bytes for node %d data\n",
+		      nd_size, nid);
+
 	nd = __va(nd_pa);
 
 	/* report and initialize */
diff --git a/mm/memblock.c b/mm/memblock.c
index f019aee..8aabb1b 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1393,7 +1393,9 @@ phys_addr_t __init memblock_phys_alloc_try_nid(phys_addr_t size, phys_addr_t ali
 
 	if (res)
 		return res;
-	return memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ACCESSIBLE);
+	return memblock_alloc_range_nid(size, align, 0,
+					MEMBLOCK_ALLOC_ACCESSIBLE,
+					NUMA_NO_NODE, MEMBLOCK_NONE);
 }
 
 /**