Re: [PATCH] powerpc/kasan: fix early boot failure on PPC32

[Michael Ellerman]

On Wed, 2019-07-31 at 06:01:42 UTC, Christophe Leroy wrote:
> Due to commit 4a6d8cf90017 ("powerpc/mm: don't use pte_alloc_kernel()
> until slab is available on PPC32"), pte_alloc_kernel() cannot be used
> during early KASAN init.
> 
> Fix it by using memblock_alloc() instead.
> 
> Reported-by: Erhard F. 
> Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
> Signed-off-by: Christophe Leroy 

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/d7e23b887f67178c4f840781be7a6aa6aeb52ab1

cheers

Re: [PATCH] powerpc/kasan: fix early boot failure on PPC32

[Christophe Leroy]

Le 31/07/2019 à 08:01, Christophe Leroy a écrit :

Due to commit 4a6d8cf90017 ("powerpc/mm: don't use pte_alloc_kernel()
until slab is available on PPC32"), pte_alloc_kernel() cannot be used
during early KASAN init.

Fix it by using memblock_alloc() instead.

Reported-by: Erhard F. 
Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
Signed-off-by: Christophe Leroy 


Cc: sta...@vger.kernel.org


---
  arch/powerpc/mm/kasan/kasan_init_32.c | 7 +--
  1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c 
b/arch/powerpc/mm/kasan/kasan_init_32.c
index 0d62be3cba47..74f4555a62ba 100644
--- a/arch/powerpc/mm/kasan/kasan_init_32.c
+++ b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -21,7 +21,7 @@ static void kasan_populate_pte(pte_t *ptep, pgprot_t prot)
__set_pte_at(_mm, va, ptep, pfn_pte(PHYS_PFN(pa), prot), 
0);
  }
  
-static int kasan_init_shadow_page_tables(unsigned long k_start, unsigned long k_end)

+static int __ref kasan_init_shadow_page_tables(unsigned long k_start, unsigned 
long k_end)
  {
pmd_t *pmd;
unsigned long k_cur, k_next;
@@ -35,7 +35,10 @@ static int kasan_init_shadow_page_tables(unsigned long 
k_start, unsigned long k_
if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte)
continue;
  
-		new = pte_alloc_one_kernel(_mm);

+   if (slab_is_available())
+   new = pte_alloc_one_kernel(_mm);
+   else
+   new = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE);
  
  		if (!new)

return -ENOMEM;

[PATCH] powerpc/kasan: fix early boot failure on PPC32

[Christophe Leroy]

Due to commit 4a6d8cf90017 ("powerpc/mm: don't use pte_alloc_kernel()
until slab is available on PPC32"), pte_alloc_kernel() cannot be used
during early KASAN init.

Fix it by using memblock_alloc() instead.

Reported-by: Erhard F. 
Fixes: 2edb16efc899 ("powerpc/32: Add KASAN support")
Signed-off-by: Christophe Leroy 
---
 arch/powerpc/mm/kasan/kasan_init_32.c | 7 +--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c 
b/arch/powerpc/mm/kasan/kasan_init_32.c
index 0d62be3cba47..74f4555a62ba 100644
--- a/arch/powerpc/mm/kasan/kasan_init_32.c
+++ b/arch/powerpc/mm/kasan/kasan_init_32.c
@@ -21,7 +21,7 @@ static void kasan_populate_pte(pte_t *ptep, pgprot_t prot)
__set_pte_at(_mm, va, ptep, pfn_pte(PHYS_PFN(pa), prot), 
0);
 }
 
-static int kasan_init_shadow_page_tables(unsigned long k_start, unsigned long 
k_end)
+static int __ref kasan_init_shadow_page_tables(unsigned long k_start, unsigned 
long k_end)
 {
pmd_t *pmd;
unsigned long k_cur, k_next;
@@ -35,7 +35,10 @@ static int kasan_init_shadow_page_tables(unsigned long 
k_start, unsigned long k_
if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte)
continue;
 
-   new = pte_alloc_one_kernel(_mm);
+   if (slab_is_available())
+   new = pte_alloc_one_kernel(_mm);
+   else
+   new = memblock_alloc(PTE_FRAG_SIZE, PTE_FRAG_SIZE);
 
if (!new)
return -ENOMEM;
-- 
2.13.3