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

Commit Message

David Hildenbrand June 4, 2024, 12:25 p.m. UTC

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

Signed-off-by: David Hildenbrand <[e-mail]>
---
 kernel/events/uprobes.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

Patch

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);
 	}