Hi all,
After merging the mm tree, today's linux-next build (arm64 defconfig)
failed like this:
arch/arm64/mm/hugetlbpage.c: In function 'huge_ptep_clear_flush':
arch/arm64/mm/hugetlbpage.c:493:16: error: implicit declaration of function 'get_clear_flush'; did you mean 'ptep_clear_flush'? [-Werror=implicit-function-declaration]
493 | return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
| ^~~~~~~~~~~~~~~
| ptep_clear_flush
arch/arm64/mm/hugetlbpage.c:493:16: error: incompatible types when returning type 'int' but 'pte_t' was expected
493 | return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/arm64/mm/hugetlbpage.c:494:1: error: control reaches end of non-void function [-Werror=return-type]
494 | }
| ^
Caused by commit
00df1f1a133b ("mm: change huge_ptep_clear_flush() to return the original pte")
interacting with commit
fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()")
I have applied the following merg fix patch for today.
From: Stephen Rothwell <[email protected]>
Date: Thu, 12 May 2022 19:33:11 +1000
Subject: [PATCH] fixup for "mm: change huge_ptep_clear_flush() to return the original pte"
It interacts with commit
fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()")
from the arm64 tree
Signed-off-by: Stephen Rothwell <[email protected]>
---
arch/arm64/mm/hugetlbpage.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 5bdf913dedc7..30f5b76aabe9 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -490,7 +490,7 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
return ptep_clear_flush(vma, addr, ptep);
ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
- return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
+ return get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig);
}
static int __init hugetlbpage_init(void)
--
2.35.1
--
Cheers,
Stephen Rothwell
On Thu, May 12, 2022 at 07:38:55PM +1000, Stephen Rothwell wrote:
> After merging the mm tree, today's linux-next build (arm64 defconfig)
> failed like this:
>
> arch/arm64/mm/hugetlbpage.c: In function 'huge_ptep_clear_flush':
> arch/arm64/mm/hugetlbpage.c:493:16: error: implicit declaration of function 'get_clear_flush'; did you mean 'ptep_clear_flush'? [-Werror=implicit-function-declaration]
> 493 | return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
> | ^~~~~~~~~~~~~~~
> | ptep_clear_flush
> arch/arm64/mm/hugetlbpage.c:493:16: error: incompatible types when returning type 'int' but 'pte_t' was expected
> 493 | return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> arch/arm64/mm/hugetlbpage.c:494:1: error: control reaches end of non-void function [-Werror=return-type]
> 494 | }
> | ^
>
> Caused by commit
>
> 00df1f1a133b ("mm: change huge_ptep_clear_flush() to return the original pte")
>
> interacting with commit
>
> fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()")
>
> I have applied the following merg fix patch for today.
>
> From: Stephen Rothwell <[email protected]>
> Date: Thu, 12 May 2022 19:33:11 +1000
> Subject: [PATCH] fixup for "mm: change huge_ptep_clear_flush() to return the original pte"
>
> It interacts with commit
>
> fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()")
>
> from the arm64 tree
>
> Signed-off-by: Stephen Rothwell <[email protected]>
> ---
> arch/arm64/mm/hugetlbpage.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
> index 5bdf913dedc7..30f5b76aabe9 100644
> --- a/arch/arm64/mm/hugetlbpage.c
> +++ b/arch/arm64/mm/hugetlbpage.c
> @@ -490,7 +490,7 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> return ptep_clear_flush(vma, addr, ptep);
>
> ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
> - return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
> + return get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig);
> }
Note that after the arm64 commit, get_clear_contig() no longer flushes
the TLB. So maybe something like:
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 30f5b76aabe9..9a999550df8e 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -485,12 +485,15 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
{
size_t pgsize;
int ncontig;
+ pte_t orig_pte;
if (!pte_cont(READ_ONCE(*ptep)))
return ptep_clear_flush(vma, addr, ptep);
ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
- return get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig);
+ orig_pte = get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig);
+ flush_tlb_range(vma, addr, addr + pgsize * ncontig);
+ return orig_pte;
}
static int __init hugetlbpage_init(void)
--
Catalin
Hi Catalin,
On Thu, 12 May 2022 12:07:41 +0100 Catalin Marinas <[email protected]> wrote:
>
> Note that after the arm64 commit, get_clear_contig() no longer flushes
> the TLB. So maybe something like:
>
> diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
> index 30f5b76aabe9..9a999550df8e 100644
> --- a/arch/arm64/mm/hugetlbpage.c
> +++ b/arch/arm64/mm/hugetlbpage.c
> @@ -485,12 +485,15 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
> {
> size_t pgsize;
> int ncontig;
> + pte_t orig_pte;
>
> if (!pte_cont(READ_ONCE(*ptep)))
> return ptep_clear_flush(vma, addr, ptep);
>
> ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
> - return get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig);
> + orig_pte = get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig);
> + flush_tlb_range(vma, addr, addr + pgsize * ncontig);
> + return orig_pte;
> }
>
> static int __init hugetlbpage_init(void)
I have modified my merge resolution patch to as in the above so it
looks like this now:
From: Stephen Rothwell <[email protected]>
Date: Fri, 13 May 2022 17:08:07 +1000
Subject: [PATCH] fixup for "mm: change huge_ptep_clear_flush() to return the original pte"
It interacts with commit
fb396bb459c1 ("arm64/hugetlb: Drop TLB flush from get_clear_flush()")
from the arm64 tree
Signed-off-by: Stephen Rothwell <[email protected]>
---
arch/arm64/mm/hugetlbpage.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c
index 5bdf913dedc7..10b4a19ed6a2 100644
--- a/arch/arm64/mm/hugetlbpage.c
+++ b/arch/arm64/mm/hugetlbpage.c
@@ -485,12 +485,15 @@ pte_t huge_ptep_clear_flush(struct vm_area_struct *vma,
{
size_t pgsize;
int ncontig;
+ pte_t orig_pte;
if (!pte_cont(READ_ONCE(*ptep)))
return ptep_clear_flush(vma, addr, ptep);
ncontig = find_num_contig(vma->vm_mm, addr, ptep, &pgsize);
- return get_clear_flush(vma->vm_mm, addr, ptep, pgsize, ncontig);
+ orig_pte = get_clear_contig(vma->vm_mm, addr, ptep, pgsize, ncontig);
+ flush_tlb_range(vma, addr, addr + pgsize * ncontig);
+ return orig_pte;
}
static int __init hugetlbpage_init(void)
--
2.35.1
--
Cheers,
Stephen Rothwell