Hi Andrew,
Just a quick fix-patch here to address some nits! :)
Thanks, Lorenzo
----8<----
>From 3656941531c0fb796f5a8ca7664832e58d468607 Mon Sep 17 00:00:00 2001
From: Lorenzo Stoakes <lorenzo.stoa...@oracle.com>
Date: Fri, 11 Jul 2025 15:06:06 +0100
Subject: [PATCH] mm/mremap: address review comments
Make seen_vma a local variable, and add a comment when vmi_needs_reset is
set to explain what it's for.
Signed-off-by: Lorenzo Stoakes <lorenzo.stoa...@oracle.com>
---
mm/mremap.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/mm/mremap.c b/mm/mremap.c
index 59f49de0f84e..142dc5287d8a 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -69,7 +69,6 @@ struct vma_remap_struct {
enum mremap_type remap_type; /* expand, shrink, etc. */
bool mmap_locked; /* Is mm currently write-locked? */
unsigned long charged; /* If VM_ACCOUNT, # pages to account. */
- bool seen_vma; /* Is >1 VMA being moved? */
bool vmi_needs_reset; /* Was the VMA iterator invalidated? */
};
@@ -1190,6 +1189,7 @@ static int copy_vma_and_data(struct vma_remap_struct *vrm,
*new_vma_ptr = NULL;
return -ENOMEM;
}
+ /* By merging, we may have invalidated any iterator in use. */
if (vma != vrm->vma)
vrm->vmi_needs_reset = true;
@@ -1807,10 +1807,10 @@ static unsigned long remap_move(struct vma_remap_struct
*vrm)
unsigned long start = vrm->addr;
unsigned long end = vrm->addr + vrm->old_len;
unsigned long new_addr = vrm->new_addr;
+ bool allowed = true, seen_vma = false;
unsigned long target_addr = new_addr;
unsigned long res = -EFAULT;
unsigned long last_end;
- bool allowed = true;
VMA_ITERATOR(vmi, current->mm, start);
/*
@@ -1828,7 +1828,7 @@ static unsigned long remap_move(struct vma_remap_struct
*vrm)
return -EFAULT;
/* No gap permitted at the start of the range. */
- if (!vrm->seen_vma && start < vma->vm_start)
+ if (!seen_vma && start < vma->vm_start)
return -EFAULT;
/*
@@ -1846,7 +1846,7 @@ static unsigned long remap_move(struct vma_remap_struct
*vrm)
*
* So we map B' at A'->vm_end + X, and C' at B'->vm_end + Y.
*/
- offset = vrm->seen_vma ? vma->vm_start - last_end : 0;
+ offset = seen_vma ? vma->vm_start - last_end : 0;
last_end = vma->vm_end;
vrm->vma = vma;
@@ -1855,7 +1855,7 @@ static unsigned long remap_move(struct vma_remap_struct
*vrm)
vrm->old_len = vrm->new_len = len;
allowed = vma_multi_allowed(vma);
- if (vrm->seen_vma && !allowed)
+ if (seen_vma && !allowed)
return -EFAULT;
res_vma = check_prep_vma(vrm);
@@ -1864,7 +1864,7 @@ static unsigned long remap_move(struct vma_remap_struct
*vrm)
if (IS_ERR_VALUE(res_vma))
return res_vma;
- if (!vrm->seen_vma) {
+ if (!seen_vma) {
VM_WARN_ON_ONCE(allowed && res_vma != new_addr);
res = res_vma;
}
@@ -1878,7 +1878,7 @@ static unsigned long remap_move(struct vma_remap_struct
*vrm)
vma_iter_reset(&vmi);
vrm->vmi_needs_reset = false;
}
- vrm->seen_vma = true;
+ seen_vma = true;
target_addr = res_vma + vrm->new_len;
}
--
2.50.0
