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a=GoEa3M9JfhUA:10 a=JfrnYn6hAAAA:8 a=yPCof4ZbAAAA:8 a=r344kw388HAGseRd6Y4A:9 a=CjuIK1q_8ugA:10 a=1CNFftbPRP8L7MoqJWF3:22 On Tue, Aug 12, 2025 at 12:39:09PM +0200, Peter Zijlstra wrote: > Ensure @rb usage doesn't extend out of the branch block. > > Signed-off-by: Peter Zijlstra (Intel) Nice to separate this out and make this bit clear. I'm guessing you're holding off on putting the rb decl into the branch as you intend in a future patch to separate out the rb branch too into a helper like tglx's original did? Reviewed-by: Lorenzo Stoakes > --- > kernel/events/core.c | 6 +----- > 1 file changed, 1 insertion(+), 5 deletions(-) > > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -7116,8 +7116,6 @@ static int perf_mmap(struct file *file, > * multiple times. > */ > ret = 0; > - /* We need the rb to map pages. */ > - rb = event->rb; > perf_mmap_account(vma, user_extra, extra); > atomic_inc(&event->mmap_count); > goto unlock; > @@ -7136,8 +7134,6 @@ static int perf_mmap(struct file *file, > goto unlock; > } > > - WARN_ON(!rb && event->rb); > - > if (vma->vm_flags & VM_WRITE) > flags |= RING_BUFFER_WRITABLE; > > @@ -7190,7 +7186,7 @@ static int perf_mmap(struct file *file, > * full cleanup in this case and therefore does not invoke > * vmops::close(). > */ > - ret = map_range(rb, vma); > + ret = map_range(event->rb, vma); > if (ret) > perf_mmap_close(vma); > > >