[PATCH 1/2] kfence: allow providing __kfence_pool in arch specific way

From: Jisheng Zhang
Date: Mon May 24 2021 - 05:26:45 EST


Some architectures may want to allocate the __kfence_pool differently
for example, allocate the __kfence_pool earlier before paging_init().
We also delay the memset() to kfence_init_pool().

Signed-off-by: Jisheng Zhang <Jisheng.Zhang@xxxxxxxxxxxxx>
---
mm/kfence/core.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/mm/kfence/core.c b/mm/kfence/core.c
index e18fbbd5d9b4..65f0210edb65 100644
--- a/mm/kfence/core.c
+++ b/mm/kfence/core.c
@@ -430,6 +430,8 @@ static bool __init kfence_init_pool(void)
if (!__kfence_pool)
return false;

+ memset(__kfence_pool, 0, KFENCE_POOL_SIZE);
+
if (!arch_kfence_init_pool())
goto err;

@@ -645,10 +647,10 @@ static DECLARE_DELAYED_WORK(kfence_timer, toggle_allocation_gate);

void __init kfence_alloc_pool(void)
{
- if (!kfence_sample_interval)
+ if (!kfence_sample_interval || __kfence_pool)
return;

- __kfence_pool = memblock_alloc(KFENCE_POOL_SIZE, PAGE_SIZE);
+ __kfence_pool = memblock_alloc_raw(KFENCE_POOL_SIZE, PAGE_SIZE);

if (!__kfence_pool)
pr_err("failed to allocate pool\n");
--
2.31.0