From: Honggang Li <ho...@redhat.com> Date: Mon, 13 Apr 2015 17:21:58 +0800
> If CONFIG_ARCH_DMA_ADDR_T_64BIT enabled for x86 systems and physical > memory is more than 4GB, dma_map_page may return a valid memory > address which greater than 0xffffffff. As a result, the mlx5 device page > allocator RB tree will be initialized with valid addresses greater than > 0xfffffff. > > However, (addr & PAGE_MASK) set the high four bytes to zeros. So, it's > impossible for the function, free_4k, to release the pages whose > addresses greater than 4GB. Memory leaks. And mlx5_ib module can't > release the pages when user try to remove the module, as a result, > system hang. > > [root@rdma05 root]# dmesg | grep addr | head > addr = 3fe384000 > addr & PAGE_MASK = fe384000 > [root@rdma05 root]# rmmod mlx5_ib <---- hang on > > ---------------------- cosnole log ----------------- > mlx5_ib 0000:04:00.0: irq 138 for MSI/MSI-X > alloc irq_desc for 139 on node -1 > alloc kstat_irqs on node -1 > mlx5_ib 0000:04:00.0: irq 139 for MSI/MSI-X > 0000:04:00.0:free_4k:221:(pid 1519): page not found > 0000:04:00.0:free_4k:221:(pid 1519): page not found > 0000:04:00.0:free_4k:221:(pid 1519): page not found > 0000:04:00.0:free_4k:221:(pid 1519): page not found > ---------------------- cosnole log ----------------- > > Signed-off-by: Honggang Li <ho...@redhat.com> Please someone at Mellanox review this. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
