[PATCH RFC 1/3] kernel/events/uprobes: pass VMA instead of MM to install_breakpoint()

David Hildenbrand
2024-06-04T12:26:10Z

... and remove the "MM" argument from remove_breakpoint(), because it
can easily be derived from the VMA.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
kernel/events/uprobes.c | 20 +++++++++++---------
1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 2c83ba776fc7b..c6d6b7a8e4410 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -886,10 +886,10 @@ static bool filter_chain(struct uprobe *uprobe,
return ret;
}

-static int
-install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
- struct vm_area_struct *vma, unsigned long vaddr)
+static int install_breakpoint(struct uprobe *uprobe, struct vm_area_struct *vma,
+ unsigned long vaddr)
{
+ struct mm_struct *mm = vma->vm_mm;
bool first_uprobe;
int ret;

@@ -914,9 +914,11 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
return ret;
}

-static int
-remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vaddr)
+static int remove_breakpoint(struct uprobe *uprobe, struct vm_area_struct *vma,
+ unsigned long vaddr)
{
+ struct mm_struct *mm = vma->vm_mm;
+
set_bit(MMF_RECALC_UPROBES, &mm->flags);
return set_orig_insn(&uprobe->arch, mm, vaddr);
}
@@ -1061,11 +1063,11 @@ register_for_each_vma(struct uprobe *uprobe, struct uprobe_consumer *new)
/* consult only the "caller", new consumer. */
if (consumer_filter(new,
UPROBE_FILTER_REGISTER, mm))
- err = install_breakpoint(uprobe, mm, vma, info->vaddr);
+ err = install_breakpoint(uprobe, vma, info->vaddr);
} else if (test_bit(MMF_HAS_UPROBES, &mm->flags)) {
if (!filter_chain(uprobe,
UPROBE_FILTER_UNREGISTER, mm))
- err |= remove_breakpoint(uprobe, mm, info->vaddr);
+ err |= remove_breakpoint(uprobe, vma, info->vaddr);
}

unlock:
@@ -1250,7 +1252,7 @@ static int unapply_uprobe(struct uprobe *uprobe, struct mm_struct *mm)
continue;

vaddr = offset_to_vaddr(vma, uprobe->offset);
- err |= remove_breakpoint(uprobe, mm, vaddr);
+ err |= remove_breakpoint(uprobe, vma, vaddr);
}
mmap_read_unlock(mm);

@@ -1386,7 +1388,7 @@ int uprobe_mmap(struct vm_area_struct *vma)
if (!fatal_signal_pending(current) &&
filter_chain(uprobe, UPROBE_FILTER_MMAP, vma->vm_mm)) {
unsigned long vaddr = offset_to_vaddr(vma, uprobe->offset);
- install_breakpoint(uprobe, vma->vm_mm, vma, vaddr);
+ install_breakpoint(uprobe, vma, vaddr);
}
put_uprobe(uprobe);
}
--
2.45.1