Messages in this thread | | | Date | Wed, 6 Jun 2012 11:18:44 +0200 | From | Ingo Molnar <> | Subject | Re: [RESEND PATCH 1/3] uprobes: Remove redundant lock_page/unlock_page |
| |
* Srikar Dronamraju <srikar@linux.vnet.ibm.com> wrote:
> From: Srikar Dronamraju <srikar@linux.vnet.ibm.com> > > Since read_opcode() reads from the referenced page and doesnt modify > the page contents nor the page attributes, there is no need to lock > the page. > > Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> > --- > Modified changelog based on comments from Peter Zijlstra > > kernel/events/uprobes.c | 2 -- > 1 files changed, 0 insertions(+), 2 deletions(-) > > diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c > index 42b21eb..b3f3095 100644 > --- a/kernel/events/uprobes.c > +++ b/kernel/events/uprobes.c > @@ -315,12 +315,10 @@ static int read_opcode(struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_ > if (ret <= 0) > return ret; > > - lock_page(page); > vaddr_new = kmap_atomic(page); > vaddr &= ~PAGE_MASK; > memcpy(opcode, vaddr_new + vaddr, UPROBE_SWBP_INSN_SIZE); > kunmap_atomic(vaddr_new); > - unlock_page(page); > > put_page(page);
Is this also a bug fix, or can it wait until v3.6?
Thanks,
Ingo
| |