Subject: Re: [PATCH] pseries: Fix 64 bit logical memory block panic

From: "Aneesh Kumar K.V" <[email-masked]>
Date: Wed, 15 Jul 2020 18:12:25 +0530

Anton Blanchard <[email-masked]> writes:

> Booting with a 4GB LMB size causes us to panic:
>
>   qemu-system-ppc64: OS terminated: OS panic:
>       Memory block size not suitable: 0x0
>
> Fix pseries_memory_block_size() to handle 64 bit LMBs.
>
> Cc: [email-masked]
> Signed-off-by: Anton Blanchard <[email-masked]>
> ---
>  arch/powerpc/platforms/pseries/hotplug-memory.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c
> index 5ace2f9a277e..6574ac33e887 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-memory.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c
> @@ -27,7 +27,7 @@ static bool rtas_hp_event;
>  unsigned long pseries_memory_block_size(void)
>  {
>  	struct device_node *np;
> -	unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
> +	uint64_t memblock_size = MIN_MEMORY_BLOCK_SIZE;
>  	struct resource r;
>  
>  	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");

We need similar changes at more places?

modified   arch/powerpc/include/asm/book3s/64/mmu.h
@@ -85,7 +85,7 @@ extern unsigned int mmu_base_pid;
 /*
  * memory block size used with radix translation.
  */
-extern unsigned int __ro_after_init radix_mem_block_size;
+extern unsigned long __ro_after_init radix_mem_block_size;
 
 #define PRTB_SIZE_SHIFT	(mmu_pid_bits + 4)
 #define PRTB_ENTRIES	(1ul << mmu_pid_bits)
modified   arch/powerpc/include/asm/drmem.h
@@ -21,7 +21,7 @@ struct drmem_lmb {
 struct drmem_lmb_info {
 	struct drmem_lmb        *lmbs;
 	int                     n_lmbs;
-	u32                     lmb_size;
+	u64                     lmb_size;
 };
 
 extern struct drmem_lmb_info *drmem_info;
modified   arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -34,7 +34,7 @@
 
 unsigned int mmu_pid_bits;
 unsigned int mmu_base_pid;
-unsigned int radix_mem_block_size __ro_after_init;
+unsigned long radix_mem_block_size __ro_after_init;
 
 static __ref void *early_alloc_pgtable(unsigned long size, int nid,
 			unsigned long region_start, unsigned long region_end)
modified   arch/powerpc/mm/drmem.c
@@ -268,14 +268,15 @@ static void __init __walk_drmem_v2_lmbs(const __be32 *prop, const __be32 *usm,
 void __init walk_drmem_lmbs_early(unsigned long node,
 			void (*func)(struct drmem_lmb *, const __be32 **))
 {
+	const __be64 *lmb_prop;
 	const __be32 *prop, *usm;
 	int len;
 
-	prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len);
-	if (!prop || len < dt_root_size_cells * sizeof(__be32))
+	lmb_prop = of_get_flat_dt_prop(node, "ibm,lmb-size", &len);
+	if (!lmb_prop || len < sizeof(__be64))
 		return;
 
-	drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
+	drmem_info->lmb_size = be64_to_cpup(lmb_prop);
 
 	usm = of_get_flat_dt_prop(node, "linux,drconf-usable-memory", &len);
 
@@ -296,19 +297,19 @@ void __init walk_drmem_lmbs_early(unsigned long node,
 
 static int __init init_drmem_lmb_size(struct device_node *dn)
 {
-	const __be32 *prop;
+	const __be64 *prop;
 	int len;
 
 	if (drmem_info->lmb_size)
 		return 0;
 
 	prop = of_get_property(dn, "ibm,lmb-size", &len);
-	if (!prop || len < dt_root_size_cells * sizeof(__be32)) {
+	if (!prop || len < sizeof(__be64)) {
 		pr_info("Could not determine LMB size\n");
 		return -1;
 	}
 
-	drmem_info->lmb_size = dt_mem_next_cell(dt_root_size_cells, &prop);
+	drmem_info->lmb_size = be64_to_cpup(prop);
 	return 0;
 }
 
modified   arch/powerpc/platforms/pseries/hotplug-memory.c
@@ -27,7 +27,7 @@ static bool rtas_hp_event;
 unsigned long pseries_memory_block_size(void)
 {
 	struct device_node *np;
-	unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
+	unsigned long memblock_size = MIN_MEMORY_BLOCK_SIZE;
 	struct resource r;
 
 	np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");