* [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling
@ 2026-09-13 17:15 Matt Vollrath
2026-09-13 17:15 ` [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel Matt Vollrath
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: Matt Vollrath @ 2026-09-13 17:15 UTC (permalink / raw)
To: intel-wired-lan
Cc: Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller,
Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, Matt Vollrath
Fix some longstanding bugs in Rx DMA error handling.
These two patches eliminate some conditions which would result in
DMA_MAPPING_ERROR being sent to h/w or to dma_unmap_page() or
dma_unmap_single(). A teardown leak in the packet-splitting path is also
fixed by a necessary refactor.
v2:
* Renamed series from "e1000e: fix Rx bugs"
* Removed RXALL buffer overrun fix from the series.
RXALL bugs will be fixed in a separate series.
* Reworded patch commit messages.
Matt Vollrath (2):
e1000e: fix Rx skb DMA map error sentinel
e1000e: fix ps_pages DMA map error sentinel
drivers/net/ethernet/intel/e1000e/netdev.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)
base-commit: 78445023439506ebd83b86d40b1e428a3b309d4a
--
2.43.0
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel 2026-09-13 17:15 [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling Matt Vollrath @ 2026-09-13 17:15 ` Matt Vollrath 2026-10-05 18:11 ` Ruinskiy, Dima 2026-09-13 17:15 ` [PATCH iwl-net v2 2/2] e1000e: fix ps_pages " Matt Vollrath 2026-09-16 12:16 ` [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling Simon Horman 2 siblings, 1 reply; 8+ messages in thread From: Matt Vollrath @ 2026-09-13 17:15 UTC (permalink / raw) To: intel-wired-lan Cc: Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, Matt Vollrath, stable Upon encountering a DMA_MAPPING_ERROR during skb allocation and mapping, the driver would leave DMA_MAPPING_ERROR in the buffer_info->dma field. This would lead several buffer_info->dma == 0 conditions down unwanted paths: * In e1000_alloc_jumbo_rx_buffers(), it would not re-attempt the failed mapping and instead write DMA_MAPPING_ERROR to the h/w descriptor on the next allocation call. On cleaning or teardown it would attempt to dma_unmap_page() DMA_MAPPING_ERROR. This case would only be reachable at MTU > 1518 and page size > 16K. * In e1000_clean_rx_ring(), it would attempt to dma_unmap_page/single() DMA_MAPPING_ERROR (unless cleaned by the jumbo path first). This case would be reachable at any combination of MTU and page size. Use buffer_info->dma = 0 as the sentinel for "DMA is not mapped." Set it immediately upon detecting the failure. The map error value was 0 on some platforms (including most common x86) until error values were unified to DMA_MAPPING_ERROR in v4.20/v5.0. Since then the error handling in this driver has been incorrect on all platforms. Signed-off-by: Matt Vollrath <tactii@gmail.com> Suggested-by: Jakub Kicinski <kuba@kernel.org> Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9 devices only)") Cc: stable@vger.kernel.org --- v2: * Add history blurb to description. --- drivers/net/ethernet/intel/e1000e/netdev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 844f31ab37ad..26f45ee8c7e7 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -691,6 +691,7 @@ static void e1000_alloc_rx_buffers(struct e1000_ring *rx_ring, adapter->rx_buffer_len, DMA_FROM_DEVICE); if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { + buffer_info->dma = 0; dev_err(&pdev->dev, "Rx DMA map failed\n"); adapter->rx_dma_failed++; break; @@ -791,6 +792,7 @@ static void e1000_alloc_rx_buffers_ps(struct e1000_ring *rx_ring, adapter->rx_ps_bsize0, DMA_FROM_DEVICE); if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { + buffer_info->dma = 0; dev_err(&pdev->dev, "Rx DMA map failed\n"); adapter->rx_dma_failed++; /* cleanup skb */ @@ -877,6 +879,7 @@ static void e1000_alloc_jumbo_rx_buffers(struct e1000_ring *rx_ring, PAGE_SIZE, DMA_FROM_DEVICE); if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { + buffer_info->dma = 0; adapter->alloc_rx_buff_failed++; break; } base-commit: 78445023439506ebd83b86d40b1e428a3b309d4a -- 2.43.0 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel 2026-09-13 17:15 ` [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel Matt Vollrath @ 2026-10-05 18:11 ` Ruinskiy, Dima 2026-10-05 19:47 ` Kadosh, MoriyaX 0 siblings, 1 reply; 8+ messages in thread From: Ruinskiy, Dima @ 2026-10-05 18:11 UTC (permalink / raw) To: Matt Vollrath, intel-wired-lan Cc: Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, stable On 13/09/2026 20:15, Matt Vollrath wrote: > Upon encountering a DMA_MAPPING_ERROR during skb allocation and mapping, > the driver would leave DMA_MAPPING_ERROR in the buffer_info->dma field. > This would lead several buffer_info->dma == 0 conditions down unwanted > paths: > > * In e1000_alloc_jumbo_rx_buffers(), it would not re-attempt the failed > mapping and instead write DMA_MAPPING_ERROR to the h/w descriptor on > the next allocation call. On cleaning or teardown it would attempt to > dma_unmap_page() DMA_MAPPING_ERROR. This case would only be > reachable at MTU > 1518 and page size > 16K. > * In e1000_clean_rx_ring(), it would attempt to dma_unmap_page/single() > DMA_MAPPING_ERROR (unless cleaned by the jumbo path first). This case > would be reachable at any combination of MTU and page size. > > Use buffer_info->dma = 0 as the sentinel for "DMA is not mapped." Set it > immediately upon detecting the failure. > > The map error value was 0 on some platforms (including most common x86) > until error values were unified to DMA_MAPPING_ERROR in v4.20/v5.0. > Since then the error handling in this driver has been incorrect on all > platforms. > > Signed-off-by: Matt Vollrath <tactii@gmail.com> > Suggested-by: Jakub Kicinski <kuba@kernel.org> > Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9 devices only)") > Cc: stable@vger.kernel.org > --- > v2: > * Add history blurb to description. > --- > drivers/net/ethernet/intel/e1000e/netdev.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c > index 844f31ab37ad..26f45ee8c7e7 100644 > --- a/drivers/net/ethernet/intel/e1000e/netdev.c > +++ b/drivers/net/ethernet/intel/e1000e/netdev.c > @@ -691,6 +691,7 @@ static void e1000_alloc_rx_buffers(struct e1000_ring *rx_ring, > adapter->rx_buffer_len, > DMA_FROM_DEVICE); > if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { > + buffer_info->dma = 0; > dev_err(&pdev->dev, "Rx DMA map failed\n"); > adapter->rx_dma_failed++; > break; > @@ -791,6 +792,7 @@ static void e1000_alloc_rx_buffers_ps(struct e1000_ring *rx_ring, > adapter->rx_ps_bsize0, > DMA_FROM_DEVICE); > if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { > + buffer_info->dma = 0; > dev_err(&pdev->dev, "Rx DMA map failed\n"); > adapter->rx_dma_failed++; > /* cleanup skb */ > @@ -877,6 +879,7 @@ static void e1000_alloc_jumbo_rx_buffers(struct e1000_ring *rx_ring, > PAGE_SIZE, > DMA_FROM_DEVICE); > if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { > + buffer_info->dma = 0; > adapter->alloc_rx_buff_failed++; > break; > } > > base-commit: 78445023439506ebd83b86d40b1e428a3b309d4a Reviewed-by: Dima Ruinskiy <dima.ruinskiy@intel.com> ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel 2026-10-05 18:11 ` Ruinskiy, Dima @ 2026-10-05 19:47 ` Kadosh, MoriyaX 0 siblings, 0 replies; 8+ messages in thread From: Kadosh, MoriyaX @ 2026-10-05 19:47 UTC (permalink / raw) To: Ruinskiy, Dima, Matt Vollrath, intel-wired-lan Cc: Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, stable On 05/10/2026 21:11, Ruinskiy, Dima wrote: > On 13/09/2026 20:15, Matt Vollrath wrote: >> Upon encountering a DMA_MAPPING_ERROR during skb allocation and mapping, >> the driver would leave DMA_MAPPING_ERROR in the buffer_info->dma field. >> This would lead several buffer_info->dma == 0 conditions down unwanted >> paths: >> >> * In e1000_alloc_jumbo_rx_buffers(), it would not re-attempt the failed >> mapping and instead write DMA_MAPPING_ERROR to the h/w descriptor on >> the next allocation call. On cleaning or teardown it would attempt to >> dma_unmap_page() DMA_MAPPING_ERROR. This case would only be >> reachable at MTU > 1518 and page size > 16K. >> * In e1000_clean_rx_ring(), it would attempt to dma_unmap_page/single() >> DMA_MAPPING_ERROR (unless cleaned by the jumbo path first). This case >> would be reachable at any combination of MTU and page size. >> >> Use buffer_info->dma = 0 as the sentinel for "DMA is not mapped." Set it >> immediately upon detecting the failure. >> >> The map error value was 0 on some platforms (including most common x86) >> until error values were unified to DMA_MAPPING_ERROR in v4.20/v5.0. >> Since then the error handling in this driver has been incorrect on all >> platforms. >> >> Signed-off-by: Matt Vollrath <tactii@gmail.com> >> Suggested-by: Jakub Kicinski <kuba@kernel.org> >> Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver >> (currently for ICH9 devices only)") >> Cc: stable@vger.kernel.org >> --- >> v2: >> * Add history blurb to description. >> --- >> drivers/net/ethernet/intel/e1000e/netdev.c | 3 +++ >> 1 file changed, 3 insertions(+) >> >> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ >> ethernet/intel/e1000e/netdev.c >> index 844f31ab37ad..26f45ee8c7e7 100644 >> --- a/drivers/net/ethernet/intel/e1000e/netdev.c >> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c >> @@ -691,6 +691,7 @@ static void e1000_alloc_rx_buffers(struct >> e1000_ring *rx_ring, >> adapter->rx_buffer_len, >> DMA_FROM_DEVICE); >> if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { >> + buffer_info->dma = 0; >> dev_err(&pdev->dev, "Rx DMA map failed\n"); >> adapter->rx_dma_failed++; >> break; >> @@ -791,6 +792,7 @@ static void e1000_alloc_rx_buffers_ps(struct >> e1000_ring *rx_ring, >> adapter->rx_ps_bsize0, >> DMA_FROM_DEVICE); >> if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { >> + buffer_info->dma = 0; >> dev_err(&pdev->dev, "Rx DMA map failed\n"); >> adapter->rx_dma_failed++; >> /* cleanup skb */ >> @@ -877,6 +879,7 @@ static void e1000_alloc_jumbo_rx_buffers(struct >> e1000_ring *rx_ring, >> PAGE_SIZE, >> DMA_FROM_DEVICE); >> if (dma_mapping_error(&pdev->dev, buffer_info->dma)) { >> + buffer_info->dma = 0; >> adapter->alloc_rx_buff_failed++; >> break; >> } >> >> base-commit: 78445023439506ebd83b86d40b1e428a3b309d4a > Reviewed-by: Dima Ruinskiy <dima.ruinskiy@intel.com> Tested-by: Moriya Kadosh <moriyax.kadosh@intel.com> ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH iwl-net v2 2/2] e1000e: fix ps_pages DMA map error sentinel 2026-09-13 17:15 [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling Matt Vollrath 2026-09-13 17:15 ` [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel Matt Vollrath @ 2026-09-13 17:15 ` Matt Vollrath 2026-10-05 18:11 ` Ruinskiy, Dima 2026-09-16 12:16 ` [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling Simon Horman 2 siblings, 1 reply; 8+ messages in thread From: Matt Vollrath @ 2026-09-13 17:15 UTC (permalink / raw) To: intel-wired-lan Cc: Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, Matt Vollrath, stable While allocating packet-split buffer pages, a failed DMA mapping would leave DMA_MAPPING_ERROR in the ps_page->dma field. This would have two consequences: * The next attempt to allocate that buffer would write DMA_MAPPING_ERROR to h/w if all pages are allocated. If the h/w uses that buffer and is handling a frame large enough to touch the affected page, it would cause a DMA fault and be dropped. The driver would then call dma_unmap_page() on DMA_MAPPING_ERROR and unknowingly send the uninitialized page up the stack as part of the frame payload. * On ring teardown, dma_unmap_page() would be called on DMA_MAPPING_ERROR. This condition is only reachable when MTU > 1500 and PAGE_SIZE <= 16K. Fix this by setting ps_page->dma = 0 upon mapping failure and separately testing ->page and ->dma during allocation and teardown. The rewrite of the ps_pages section of e1000_clean_rx_ring was necessary to recognize the case of an allocated page without a valid DMA mapping. It also fixes a separate bug which would potentially leak pages on ring teardown. The cleaner stops cleaning pages when h/w reported that it did not write to a page in the sequence, leaving the following pages allocated and mapped. The teardown would then break early and leak the unused mapped pages. If the ring is re-constructed by down/up with similar configuration, it would reclaim those lost pages. This would only affect configurations with rx_ps_pages >= 2 (MTU > PAGE_SIZE) and the same condition of MTU > 1500 and PAGE_SIZE <= 16K. Signed-off-by: Matt Vollrath <tactii@gmail.com> Assisted-by: Claude:claude-5-fable Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9 devices only)") Cc: stable@vger.kernel.org --- v2: * Reword last paragraph of description. --- drivers/net/ethernet/intel/e1000e/netdev.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c index 26f45ee8c7e7..063fc8cd2673 100644 --- a/drivers/net/ethernet/intel/e1000e/netdev.c +++ b/drivers/net/ethernet/intel/e1000e/netdev.c @@ -759,12 +759,15 @@ static void e1000_alloc_rx_buffers_ps(struct e1000_ring *rx_ring, adapter->alloc_rx_buff_failed++; goto no_buffers; } + } + if (!ps_page->dma) { ps_page->dma = dma_map_page(&pdev->dev, ps_page->page, 0, PAGE_SIZE, DMA_FROM_DEVICE); if (dma_mapping_error(&pdev->dev, ps_page->dma)) { + ps_page->dma = 0; dev_err(&adapter->pdev->dev, "Rx DMA page map failed\n"); adapter->rx_dma_failed++; @@ -1722,13 +1725,15 @@ static void e1000_clean_rx_ring(struct e1000_ring *rx_ring) for (j = 0; j < PS_PAGE_BUFFERS; j++) { ps_page = &buffer_info->ps_pages[j]; - if (!ps_page->page) - break; - dma_unmap_page(&pdev->dev, ps_page->dma, PAGE_SIZE, - DMA_FROM_DEVICE); - ps_page->dma = 0; - put_page(ps_page->page); - ps_page->page = NULL; + if (ps_page->dma) { + dma_unmap_page(&pdev->dev, ps_page->dma, + PAGE_SIZE, DMA_FROM_DEVICE); + ps_page->dma = 0; + } + if (ps_page->page) { + put_page(ps_page->page); + ps_page->page = NULL; + } } } -- 2.43.0 ^ permalink raw reply related [flat|nested] 8+ messages in thread
* Re: [PATCH iwl-net v2 2/2] e1000e: fix ps_pages DMA map error sentinel 2026-09-13 17:15 ` [PATCH iwl-net v2 2/2] e1000e: fix ps_pages " Matt Vollrath @ 2026-10-05 18:11 ` Ruinskiy, Dima 2026-10-05 19:46 ` Kadosh, MoriyaX 0 siblings, 1 reply; 8+ messages in thread From: Ruinskiy, Dima @ 2026-10-05 18:11 UTC (permalink / raw) To: Matt Vollrath, intel-wired-lan Cc: Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, stable On 13/09/2026 20:15, Matt Vollrath wrote: > While allocating packet-split buffer pages, a failed DMA mapping would > leave DMA_MAPPING_ERROR in the ps_page->dma field. > > This would have two consequences: > * The next attempt to allocate that buffer would write DMA_MAPPING_ERROR > to h/w if all pages are allocated. If the h/w uses that buffer and is > handling a frame large enough to touch the affected page, it would > cause a DMA fault and be dropped. The driver would then call > dma_unmap_page() on DMA_MAPPING_ERROR and unknowingly send the > uninitialized page up the stack as part of the frame payload. > * On ring teardown, dma_unmap_page() would be called on > DMA_MAPPING_ERROR. > > This condition is only reachable when MTU > 1500 and PAGE_SIZE <= 16K. > > Fix this by setting ps_page->dma = 0 upon mapping failure and separately > testing ->page and ->dma during allocation and teardown. > > The rewrite of the ps_pages section of e1000_clean_rx_ring was necessary > to recognize the case of an allocated page without a valid DMA mapping. > It also fixes a separate bug which would potentially leak pages on ring > teardown. The cleaner stops cleaning pages when h/w reported that it did > not write to a page in the sequence, leaving the following pages > allocated and mapped. The teardown would then break early and leak the > unused mapped pages. If the ring is re-constructed by down/up with > similar configuration, it would reclaim those lost pages. This would > only affect configurations with rx_ps_pages >= 2 (MTU > PAGE_SIZE) and > the same condition of MTU > 1500 and PAGE_SIZE <= 16K. > > Signed-off-by: Matt Vollrath <tactii@gmail.com> > Assisted-by: Claude:claude-5-fable > Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver (currently for ICH9 devices only)") > Cc: stable@vger.kernel.org > --- > v2: > * Reword last paragraph of description. > --- > drivers/net/ethernet/intel/e1000e/netdev.c | 19 ++++++++++++------- > 1 file changed, 12 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c > index 26f45ee8c7e7..063fc8cd2673 100644 > --- a/drivers/net/ethernet/intel/e1000e/netdev.c > +++ b/drivers/net/ethernet/intel/e1000e/netdev.c > @@ -759,12 +759,15 @@ static void e1000_alloc_rx_buffers_ps(struct e1000_ring *rx_ring, > adapter->alloc_rx_buff_failed++; > goto no_buffers; > } > + } > + if (!ps_page->dma) { > ps_page->dma = dma_map_page(&pdev->dev, > ps_page->page, > 0, PAGE_SIZE, > DMA_FROM_DEVICE); > if (dma_mapping_error(&pdev->dev, > ps_page->dma)) { > + ps_page->dma = 0; > dev_err(&adapter->pdev->dev, > "Rx DMA page map failed\n"); > adapter->rx_dma_failed++; > @@ -1722,13 +1725,15 @@ static void e1000_clean_rx_ring(struct e1000_ring *rx_ring) > > for (j = 0; j < PS_PAGE_BUFFERS; j++) { > ps_page = &buffer_info->ps_pages[j]; > - if (!ps_page->page) > - break; > - dma_unmap_page(&pdev->dev, ps_page->dma, PAGE_SIZE, > - DMA_FROM_DEVICE); > - ps_page->dma = 0; > - put_page(ps_page->page); > - ps_page->page = NULL; > + if (ps_page->dma) { > + dma_unmap_page(&pdev->dev, ps_page->dma, > + PAGE_SIZE, DMA_FROM_DEVICE); > + ps_page->dma = 0; > + } > + if (ps_page->page) { > + put_page(ps_page->page); > + ps_page->page = NULL; > + } > } > } > Reviewed-by: Dima Ruinskiy <dima.ruinskiy@intel.com> ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH iwl-net v2 2/2] e1000e: fix ps_pages DMA map error sentinel 2026-10-05 18:11 ` Ruinskiy, Dima @ 2026-10-05 19:46 ` Kadosh, MoriyaX 0 siblings, 0 replies; 8+ messages in thread From: Kadosh, MoriyaX @ 2026-10-05 19:46 UTC (permalink / raw) To: Ruinskiy, Dima, Matt Vollrath, intel-wired-lan Cc: Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev, stable On 05/10/2026 21:11, Ruinskiy, Dima wrote: > On 13/09/2026 20:15, Matt Vollrath wrote: >> While allocating packet-split buffer pages, a failed DMA mapping would >> leave DMA_MAPPING_ERROR in the ps_page->dma field. >> >> This would have two consequences: >> * The next attempt to allocate that buffer would write DMA_MAPPING_ERROR >> to h/w if all pages are allocated. If the h/w uses that buffer and is >> handling a frame large enough to touch the affected page, it would >> cause a DMA fault and be dropped. The driver would then call >> dma_unmap_page() on DMA_MAPPING_ERROR and unknowingly send the >> uninitialized page up the stack as part of the frame payload. >> * On ring teardown, dma_unmap_page() would be called on >> DMA_MAPPING_ERROR. >> >> This condition is only reachable when MTU > 1500 and PAGE_SIZE <= 16K. >> >> Fix this by setting ps_page->dma = 0 upon mapping failure and separately >> testing ->page and ->dma during allocation and teardown. >> >> The rewrite of the ps_pages section of e1000_clean_rx_ring was necessary >> to recognize the case of an allocated page without a valid DMA mapping. >> It also fixes a separate bug which would potentially leak pages on ring >> teardown. The cleaner stops cleaning pages when h/w reported that it did >> not write to a page in the sequence, leaving the following pages >> allocated and mapped. The teardown would then break early and leak the >> unused mapped pages. If the ring is re-constructed by down/up with >> similar configuration, it would reclaim those lost pages. This would >> only affect configurations with rx_ps_pages >= 2 (MTU > PAGE_SIZE) and >> the same condition of MTU > 1500 and PAGE_SIZE <= 16K. >> >> Signed-off-by: Matt Vollrath <tactii@gmail.com> >> Assisted-by: Claude:claude-5-fable >> Fixes: bc7f75fa9788 ("[E1000E]: New pci-express e1000 driver >> (currently for ICH9 devices only)") >> Cc: stable@vger.kernel.org >> --- >> v2: >> * Reword last paragraph of description. >> --- >> drivers/net/ethernet/intel/e1000e/netdev.c | 19 ++++++++++++------- >> 1 file changed, 12 insertions(+), 7 deletions(-) >> >> diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ >> ethernet/intel/e1000e/netdev.c >> index 26f45ee8c7e7..063fc8cd2673 100644 >> --- a/drivers/net/ethernet/intel/e1000e/netdev.c >> +++ b/drivers/net/ethernet/intel/e1000e/netdev.c >> @@ -759,12 +759,15 @@ static void e1000_alloc_rx_buffers_ps(struct >> e1000_ring *rx_ring, >> adapter->alloc_rx_buff_failed++; >> goto no_buffers; >> } >> + } >> + if (!ps_page->dma) { >> ps_page->dma = dma_map_page(&pdev->dev, >> ps_page->page, >> 0, PAGE_SIZE, >> DMA_FROM_DEVICE); >> if (dma_mapping_error(&pdev->dev, >> ps_page->dma)) { >> + ps_page->dma = 0; >> dev_err(&adapter->pdev->dev, >> "Rx DMA page map failed\n"); >> adapter->rx_dma_failed++; >> @@ -1722,13 +1725,15 @@ static void e1000_clean_rx_ring(struct >> e1000_ring *rx_ring) >> for (j = 0; j < PS_PAGE_BUFFERS; j++) { >> ps_page = &buffer_info->ps_pages[j]; >> - if (!ps_page->page) >> - break; >> - dma_unmap_page(&pdev->dev, ps_page->dma, PAGE_SIZE, >> - DMA_FROM_DEVICE); >> - ps_page->dma = 0; >> - put_page(ps_page->page); >> - ps_page->page = NULL; >> + if (ps_page->dma) { >> + dma_unmap_page(&pdev->dev, ps_page->dma, >> + PAGE_SIZE, DMA_FROM_DEVICE); >> + ps_page->dma = 0; >> + } >> + if (ps_page->page) { >> + put_page(ps_page->page); >> + ps_page->page = NULL; >> + } >> } >> } > Reviewed-by: Dima Ruinskiy <dima.ruinskiy@intel.com> Tested-by: Moriya Kadosh <moriyax.kadosh@intel.com> ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling 2026-09-13 17:15 [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling Matt Vollrath 2026-09-13 17:15 ` [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel Matt Vollrath 2026-09-13 17:15 ` [PATCH iwl-net v2 2/2] e1000e: fix ps_pages " Matt Vollrath @ 2026-09-16 12:16 ` Simon Horman 2 siblings, 0 replies; 8+ messages in thread From: Simon Horman @ 2026-09-16 12:16 UTC (permalink / raw) To: Matt Vollrath Cc: intel-wired-lan, Tony Nguyen, Przemek Kitszel, Andrew Lunn, David S . Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni, netdev On Sun, Sep 13, 2026 at 01:15:53PM -0400, Matt Vollrath wrote: > Fix some longstanding bugs in Rx DMA error handling. > > These two patches eliminate some conditions which would result in > DMA_MAPPING_ERROR being sent to h/w or to dma_unmap_page() or > dma_unmap_single(). A teardown leak in the packet-splitting path is also > fixed by a necessary refactor. > > v2: > * Renamed series from "e1000e: fix Rx bugs" > * Removed RXALL buffer overrun fix from the series. > RXALL bugs will be fixed in a separate series. > * Reworded patch commit messages. For the series: Reviewed-by: Simon Horman <horms@kernel.org> ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2026-10-05 19:50 UTC | newest] Thread overview: 8+ messages (download: mbox.gz follow: Atom feed -- links below jump to the message on this page -- 2026-09-13 17:15 [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling Matt Vollrath 2026-09-13 17:15 ` [PATCH iwl-net v2 1/2] e1000e: fix Rx skb DMA map error sentinel Matt Vollrath 2026-10-05 18:11 ` Ruinskiy, Dima 2026-10-05 19:47 ` Kadosh, MoriyaX 2026-09-13 17:15 ` [PATCH iwl-net v2 2/2] e1000e: fix ps_pages " Matt Vollrath 2026-10-05 18:11 ` Ruinskiy, Dima 2026-10-05 19:46 ` Kadosh, MoriyaX 2026-09-16 12:16 ` [PATCH iwl-net v2 0/2] e1000e: fix Rx DMA error handling Simon Horman
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