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In net_dm_packet_trace_kfree_skb_hit() and net_dm_hw_trap_packet_probe(), u64_stats_update_begin() / u64_stats_inc() / u64_stats_update_end() were called after spin_unlock_irqrestore(&...drop_queue.lock, flags), when local IRQs had already been re-enabled. Tracepoint probes can execute in IRQ or softirq context. On 32-bit architectures, u64_stats_update_begin() disables preemption but not interrupts, relying on seqcount writes. If a nested interrupt occurs on the same CPU during the 64-bit stats update, the reentrant seqcount update can corrupt the seqcount state or stats value. Fix this by performing the 64-bit per-CPU stats update before releasing drop_queue.lock via spin_unlock_irqrestore(), ensuring local interrupts remain disabled during the u64_stats update. Fixes:e9feb58020("drop_monitor: Expose tail drop counter") Fixes:5e58109b1e("drop_monitor: Add support for packet alert mode for hardware drops") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20260722141743.3266924-3-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1784 lines
42 KiB
1784 lines
42 KiB