From: Aaron Tomlin Date: Thu, 26 Feb 2026 16:31:21 +0000 (-0500) Subject: vmxnet3: Suppress page allocation warning for massive Rx Data ring X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=c31770c49348fb019167fa95119f330597c99193;p=thirdparty%2Fkernel%2Flinux.git vmxnet3: Suppress page allocation warning for massive Rx Data ring The vmxnet3 driver supports an Rx Data ring (rx-mini) to optimise the processing of small packets. The size of this ring's DMA-coherent memory allocation is determined by the product of the primary Rx ring size and the data ring descriptor size: sz = rq->rx_ring[0].size * rq->data_ring.desc_size; When a user configures the maximum supported parameters via ethtool (rx_ring[0].size = 4096, data_ring.desc_size = 2048), the required contiguous memory allocation reaches 8 MB (8,388,608 bytes). In environments lacking Contiguous Memory Allocator (CMA), dma_alloc_coherent() falls back to the standard zone buddy allocator. An 8 MB allocation translates to a page order of 11, which strictly exceeds the default MAX_PAGE_ORDER (10) on most architectures. Consequently, __alloc_pages_noprof() catches the oversize request and triggers a loud kernel warning stack trace: WARN_ON_ONCE_GFP(order > MAX_PAGE_ORDER, gfp) This warning is unnecessary and alarming to system administrators because the vmxnet3 driver already handles this allocation failure gracefully. If dma_alloc_coherent() returns NULL, the driver safely disables the Rx Data ring (adapter->rxdataring_enabled = false) and falls back to standard, streaming DMA packet processing. To resolve this, append the __GFP_NOWARN flag to the dma_alloc_coherent() gfp_mask. This instructs the page allocator to silently fail the allocation if it exceeds order limits or memory is too fragmented, preventing the spurious warning stack trace. Furthermore, enhance the subsequent netdev_err() fallback message to include the requested allocation size. This provides critical debugging context to the administrator (e.g., revealing that an 8 MB allocation was attempted and failed) without making hardcoded assumptions about the state of the system's configurations. Reviewed-by: Jijie Shao Signed-off-by: Aaron Tomlin Link: https://patch.msgid.link/20260226163121.4045808-1-atomlin@atomlin.com Signed-off-by: Jakub Kicinski --- diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c index 0572f6a9bdb62..40522afc05320 100644 --- a/drivers/net/vmxnet3/vmxnet3_drv.c +++ b/drivers/net/vmxnet3/vmxnet3_drv.c @@ -2268,10 +2268,10 @@ vmxnet3_rq_create(struct vmxnet3_rx_queue *rq, struct vmxnet3_adapter *adapter) rq->data_ring.base = dma_alloc_coherent(&adapter->pdev->dev, sz, &rq->data_ring.basePA, - GFP_KERNEL); + GFP_KERNEL | __GFP_NOWARN); if (!rq->data_ring.base) { netdev_err(adapter->netdev, - "rx data ring will be disabled\n"); + "failed to allocate %zu bytes, rx data ring will be disabled\n", sz); adapter->rxdataring_enabled = false; } } else {