On Wed, Jan 22, 2025 at 10:38 AM Saket Kumar Bhaskar <skb99@xxxxxxxxxxxxx> wrote: > > For platforms on powerpc architecture with a default page size greater > than 4096, there was an inconsistency in fragment size calculation. > This caused the BPF selftest xdp_adjust_tail/xdp_adjust_frags_tail_grow > to fail on powerpc. > > The issue occurred because the fragment buffer size in > bpf_prog_test_run_xdp() was set to 4096, while the actual data size in > the fragment within the shared skb was checked against PAGE_SIZE > (65536 on powerpc) in min_t, causing it to exceed 4096 and be set > accordingly. This discrepancy led to an overflow when > bpf_xdp_frags_increase_tail() checked for tailroom, as skb_frag_size(frag) > could be greater than rxq->frag_size (when PAGE_SIZE > 4096). > > This commit updates the page size references to 4096 to ensure consistency > and prevent overflow issues in fragment size calculations. This isn't right. Please fix the selftest instead. pw-bot: cr
