Gh0st
/
linux
mirror of https://github.com/torvalds/linux.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

uprobes: Add do_ref_ctr argument to uprobe_write function 

Making update_ref_ctr call in uprobe_write conditional based
on do_ref_ctr argument. This way we can use uprobe_write for
instruction update without doing ref_ctr_offset update.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20250720112133.244369-8-jolsa@kernel.org
This commit is contained in:
Jiri Olsa 2025-07-20 13:21:17 +02:00 committed by Peter Zijlstra
parent ec46350fe1
commit 18a111256a
2 changed files with 5 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/linux/uprobes.h
View File

@ -200,7 +200,7 @@ extern unsigned long uprobe_get_trap_addr(struct pt_regs *regs);
extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct vm_area_struct *vma, unsigned long vaddr, uprobe_opcode_t, extern int uprobe_write_opcode(struct arch_uprobe *auprobe, struct vm_area_struct *vma, unsigned long vaddr, uprobe_opcode_t,
bool is_register); bool is_register);
extern int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, const unsigned long opcode_vaddr, extern int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, const unsigned long opcode_vaddr,
uprobe_opcode_t *insn, int nbytes, uprobe_write_verify_t verify, bool is_register); uprobe_opcode_t *insn, int nbytes, uprobe_write_verify_t verify, bool is_register, bool do_update_ref_ctr);
extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc); extern struct uprobe *uprobe_register(struct inode *inode, loff_t offset, loff_t ref_ctr_offset, struct uprobe_consumer *uc);
extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool); extern int uprobe_apply(struct uprobe *uprobe, struct uprobe_consumer *uc, bool);
extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc); extern void uprobe_unregister_nosync(struct uprobe *uprobe, struct uprobe_consumer *uc);

8
kernel/events/uprobes.c
View File

@ -491,12 +491,12 @@ int uprobe_write_opcode(struct arch_uprobe *auprobe, struct vm_area_struct *vma,
bool is_register) bool is_register)
{ {
return uprobe_write(auprobe, vma, opcode_vaddr, &opcode, UPROBE_SWBP_INSN_SIZE, return uprobe_write(auprobe, vma, opcode_vaddr, &opcode, UPROBE_SWBP_INSN_SIZE,
verify_opcode, is_register); verify_opcode, is_register, true /* do_update_ref_ctr */);
} }
int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma, int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma,
const unsigned long insn_vaddr, uprobe_opcode_t *insn, int nbytes, const unsigned long insn_vaddr, uprobe_opcode_t *insn, int nbytes,
uprobe_write_verify_t verify, bool is_register) uprobe_write_verify_t verify, bool is_register, bool do_update_ref_ctr)
{ {
const unsigned long vaddr = insn_vaddr & PAGE_MASK; const unsigned long vaddr = insn_vaddr & PAGE_MASK;
struct mm_struct *mm = vma->vm_mm; struct mm_struct *mm = vma->vm_mm;
@ -537,7 +537,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma,
} }
/* We are going to replace instruction, update ref_ctr. */ /* We are going to replace instruction, update ref_ctr. */
if (!ref_ctr_updated && uprobe->ref_ctr_offset) { if (do_update_ref_ctr && !ref_ctr_updated && uprobe->ref_ctr_offset) {
ret = update_ref_ctr(uprobe, mm, is_register ? 1 : -1); ret = update_ref_ctr(uprobe, mm, is_register ? 1 : -1);
if (ret) { if (ret) {
folio_put(folio); folio_put(folio);
@ -589,7 +589,7 @@ int uprobe_write(struct arch_uprobe *auprobe, struct vm_area_struct *vma,
out: out:
/* Revert back reference counter if instruction update failed. */ /* Revert back reference counter if instruction update failed. */
if (ret < 0 && ref_ctr_updated) if (do_update_ref_ctr && ret < 0 && ref_ctr_updated)
update_ref_ctr(uprobe, mm, is_register ? -1 : 1); update_ref_ctr(uprobe, mm, is_register ? -1 : 1);
/* try collapse pmd for compound page */ /* try collapse pmd for compound page */