mvneta_swbm_add_rx_fragment() sets XDP_FLAGS_FRAGS_PF_MEMALLOC on the xdp_buff when a fragment page is a pfmemalloc one (page under memory pressure). The xdp_buff is reused for the next frame, but only the XDP_FLAGS_HAS_FRAGS bit was cleared at frame start, so the pfmemalloc bit leaked from one frame into the following ones. mvneta_swbm_build_skb() propagates the flag to skb->pfmemalloc through xdp_update_skb_frags_info(), so the skb of a subsequent fragmented frame could be wrongly marked as pfmemalloc even if none of its pages are under pressure. Clear all the xdp_buff flags in mvneta_swbm_rx_frame(), which is invoked for each new frame, instead of just the XDP_FLAGS_HAS_FRAGS bit. Fixes: ed7a58cb40bd ("net: marvell: rely on xdp_update_skb_shared_info utility routine") Reviewed-by: Simon Horman Signed-off-by: Lorenzo Bianconi --- Changes in v4: - Rename xdp_reinit_buf() in xdp_reinit_buff(). - Link to v3: https://lore.kernel.org/r/20260928-mvneta-xdp-clear-frag-fix-v3-1-af4a51499eaf@oss.qualcomm.com Changes in v3: - Rename xdp_buff_clear_flags() in xdp_reinit_buf(). - Link to v2: https://lore.kernel.org/r/20260923-mvneta-xdp-clear-frag-fix-v2-1-298693a7ea6b@oss.qualcomm.com Changes in v2: - Introduce xdp_buff_clear_flags() utility routine. - Link to v1: https://lore.kernel.org/r/20260920-mvneta-xdp-clear-frag-fix-v1-1-d7efadecf959@oss.qualcomm.com --- drivers/net/ethernet/marvell/mvneta.c | 2 +- include/net/xdp.h | 5 +++++ 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c index 543e566425c1..4f479b6f731e 100644 --- a/drivers/net/ethernet/marvell/mvneta.c +++ b/drivers/net/ethernet/marvell/mvneta.c @@ -2340,7 +2340,7 @@ mvneta_swbm_rx_frame(struct mvneta_port *pp, /* Prefetch header */ prefetch(data); - xdp_buff_clear_frags_flag(xdp); + xdp_reinit_buff(xdp); xdp_prepare_buff(xdp, data, pp->rx_offset_correction + MVNETA_MH_SIZE, data_len, true); } diff --git a/include/net/xdp.h b/include/net/xdp.h index aa742f413c35..07231adfb5f8 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -106,6 +106,11 @@ struct xdp_buff { }; }; +static __always_inline void xdp_reinit_buff(struct xdp_buff *xdp) +{ + xdp->flags = 0; +} + static __always_inline bool xdp_buff_has_frags(const struct xdp_buff *xdp) { return !!(xdp->flags & XDP_FLAGS_HAS_FRAGS); --- base-commit: 54518e0e827f4ca9229ae657022c60bf60f5c1bf change-id: 20260919-mvneta-xdp-clear-frag-fix-7ac691e1659b Best regards, -- Lorenzo Bianconi