Re: [PATCH 1/3] powerpc/mm: Initialize the HPTE encoding values

From: Aneesh Kumar K.V
Date: Thu Sep 12 2019 - 09:37:40 EST


On 8/30/19 5:37 PM, Laurent Dufour wrote:
Before reading the HPTE encoding values we initialize all of them to -1 (an
invalid value) to later being able to detect the initialized ones.

Signed-off-by: Laurent Dufour <ldufour@xxxxxxxxxxxxx>
---
arch/powerpc/mm/book3s64/hash_utils.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/hash_utils.c b/arch/powerpc/mm/book3s64/hash_utils.c
index c3bfef08dcf8..2039bc315459 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c
@@ -408,7 +408,7 @@ static int __init htab_dt_scan_page_sizes(unsigned long node,
{
const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
const __be32 *prop;
- int size = 0;
+ int size = 0, idx, base_idx;
/* We are scanning "cpu" nodes only */
if (type == NULL || strcmp(type, "cpu") != 0)
@@ -418,6 +418,11 @@ static int __init htab_dt_scan_page_sizes(unsigned long node,
if (!prop)
return 0;
+ /* Set all the penc values to invalid */
+ for (base_idx = 0; base_idx < MMU_PAGE_COUNT; base_idx++)
+ for (idx = 0; idx < MMU_PAGE_COUNT; idx++)
+ mmu_psize_defs[base_idx].penc[idx] = -1;
+
pr_info("Page sizes from device-tree:\n");
size /= 4;
cur_cpu_spec->mmu_features &= ~(MMU_FTR_16M_PAGE);
@@ -426,7 +431,6 @@ static int __init htab_dt_scan_page_sizes(unsigned long node,
unsigned int slbenc = be32_to_cpu(prop[1]);
unsigned int lpnum = be32_to_cpu(prop[2]);
struct mmu_psize_def *def;
- int idx, base_idx;
size -= 3; prop += 3;
base_idx = get_idx_from_shift(base_shift);


We already do this in mmu_psize_set_default_penc() ?

-aneesh