linux-kernel - [PATCH 4/4] memblock: stop poisoning raw allocations

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Date:   Wed, 14 Jul 2021 15:37:39 +0300
From:   Mike Rapoport <rppt@...nel.org>
To:     Andrew Morton <akpm@...ux-foundation.org>
Cc:     Michal Simek <monstr@...str.eu>, Mike Rapoport <rppt@...nel.org>,
        Mike Rapoport <rppt@...ux.ibm.com>,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: [PATCH 4/4] memblock: stop poisoning raw allocations

From: Mike Rapoport <rppt@...ux.ibm.com>

Functions memblock_alloc_exact_nid_raw() and memblock_alloc_try_nid_raw()
are intended for early memory allocation without overhead of zeroing the
allocated memory. Since these functions were used to allocate the memory
map, they have ended up with addition of a call to page_init_poison() that
poisoned the allocated memory when CONFIG_PAGE_POISON was set.

Since the memory map is allocated using a dedicated memmep_alloc() function
that takes care of the poisoning, remove page poisoning from the
memblock_alloc_*_raw() functions.

Signed-off-by: Mike Rapoport <rppt@...ux.ibm.com>
---
 mm/memblock.c | 20 ++++----------------
 1 file changed, 4 insertions(+), 16 deletions(-)

diff --git a/mm/memblock.c b/mm/memblock.c
index 0041ff62c584..9748d0689f81 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -1490,18 +1490,12 @@ void * __init memblock_alloc_exact_nid_raw(
 			phys_addr_t min_addr, phys_addr_t max_addr,
 			int nid)
 {
-	void *ptr;
-
 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
 		     __func__, (u64)size, (u64)align, nid, &min_addr,
 		     &max_addr, (void *)_RET_IP_);
 
-	ptr = memblock_alloc_internal(size, align,
-					   min_addr, max_addr, nid, true);
-	if (ptr && size > 0)
-		page_init_poison(ptr, size);
-
-	return ptr;
+	return memblock_alloc_internal(size, align, min_addr, max_addr, nid,
+				       true);
 }
 
 /**
@@ -1528,18 +1522,12 @@ void * __init memblock_alloc_try_nid_raw(
 			phys_addr_t min_addr, phys_addr_t max_addr,
 			int nid)
 {
-	void *ptr;
-
 	memblock_dbg("%s: %llu bytes align=0x%llx nid=%d from=%pa max_addr=%pa %pS\n",
 		     __func__, (u64)size, (u64)align, nid, &min_addr,
 		     &max_addr, (void *)_RET_IP_);
 
-	ptr = memblock_alloc_internal(size, align,
-					   min_addr, max_addr, nid, false);
-	if (ptr && size > 0)
-		page_init_poison(ptr, size);
-
-	return ptr;
+	return memblock_alloc_internal(size, align, min_addr, max_addr, nid,
+				       false);
 }
 
 /**
-- 
2.28.0