[dpdk-dev] [PATCH v4] bus/pci: align next mapping address on page boundary

[dpdk-dev] [PATCH v4] bus/pci: align next mapping address on page boundary

[Wangyu (Eric)]

Currently, the next address picked by PCI mapping infrastructure
may be page-unaligned due to BAR length being smaller than page size.
This leads to a situation where the requested map address is invalid,
resulting in mmap() call returning an arbitrary address,
which will later interfere with device BAR mapping in secondary processes.

Fix it by always aligning the next requested address on page boundary.

Signed-off-by: Xiaofeng Deng <dengxiaofeng@huawei.com>
Signed-off-by: Wangyu (Eric) <seven.wangyu@huawei.com>
Acked-by: Wei Hu <xavier.huwei@huawei.com>
Acked-by: Min Hu <humin29@huawei.com>
Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
Acked-by: Gavin Hu (Arm Technology China) <Gavin.Hu@arm.com>

Fixes: c752998b5e2e ("pci: introduce library and driver")
Cc: stable@dpdk.org
---
 drivers/bus/pci/linux/pci_uio.c  | 2 ++  drivers/bus/pci/linux/pci_vfio.c | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/drivers/bus/pci/linux/pci_uio.c b/drivers/bus/pci/linux/pci_uio.c index 6dca05a..097dc19 100644
--- a/drivers/bus/pci/linux/pci_uio.c
+++ b/drivers/bus/pci/linux/pci_uio.c
@@ -351,6 +351,8 @@
 	pci_map_addr = RTE_PTR_ADD(mapaddr,
 			(size_t)dev->mem_resource[res_idx].len);
 
+	pci_map_addr = RTE_PTR_ALIGN(pci_map_addr, sysconf(_SC_PAGE_SIZE));
+
 	maps[map_idx].phaddr = dev->mem_resource[res_idx].phys_addr;
 	maps[map_idx].size = dev->mem_resource[res_idx].len;
 	maps[map_idx].addr = mapaddr;
diff --git a/drivers/bus/pci/linux/pci_vfio.c b/drivers/bus/pci/linux/pci_vfio.c
index b8faa23..64cd84a 100644
--- a/drivers/bus/pci/linux/pci_vfio.c
+++ b/drivers/bus/pci/linux/pci_vfio.c
@@ -750,6 +750,9 @@
 		bar_addr = pci_map_addr;
 		pci_map_addr = RTE_PTR_ADD(bar_addr, (size_t) reg->size);
 
+		pci_map_addr = RTE_PTR_ALIGN(pci_map_addr,
+					sysconf(_SC_PAGE_SIZE));
+
 		maps[i].addr = bar_addr;
 		maps[i].offset = reg->offset;
 		maps[i].size = reg->size;
--
1.8.3.1

Re: [dpdk-dev] [PATCH v4] bus/pci: align next mapping address on page boundary

[David Marchand]

On Wed, Nov 13, 2019 at 8:17 AM Wangyu (Eric) <seven.wangyu@huawei.com> wrote:
>
> Currently, the next address picked by PCI mapping infrastructure
> may be page-unaligned due to BAR length being smaller than page size.
> This leads to a situation where the requested map address is invalid,
> resulting in mmap() call returning an arbitrary address,
> which will later interfere with device BAR mapping in secondary processes.
>
> Fix it by always aligning the next requested address on page boundary.
>
> Signed-off-by: Xiaofeng Deng <dengxiaofeng@huawei.com>
> Signed-off-by: Wangyu (Eric) <seven.wangyu@huawei.com>
> Acked-by: Wei Hu <xavier.huwei@huawei.com>
> Acked-by: Min Hu <humin29@huawei.com>
> Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
> Acked-by: Gavin Hu (Arm Technology China) <Gavin.Hu@arm.com>
>
> Fixes: c752998b5e2e ("pci: introduce library and driver")
> Cc: stable@dpdk.org

Cc'd stable.

Applied, thanks.



--
David Marchand