• Peng Fan's avatar
    drivers: base: dma-mapping: page align the size when unmap_kernel_range · 1ccdc775
    Peng Fan authored
    commit 85714108 upstream.
    
    When dma_common_free_remap, the input parameter 'size' may not
    be page aligned. And, met kernel warning when doing iommu dma
    for usb on i.MX8 platform:
    "
    WARNING: CPU: 0 PID: 869 at mm/vmalloc.c:70 vunmap_page_range+0x1cc/0x1d0()
    Modules linked in:
    CPU: 0 PID: 869 Comm: kworker/u8:2 Not tainted 4.1.12-00444-gc5f9d1d-dirty #147
    Hardware name: Freescale i.MX8DV Sabreauto (DT)
    Workqueue: ci_otg ci_otg_work
    Call trace:
    [<ffffffc000089920>] dump_backtrace+0x0/0x124
    [<ffffffc000089a54>] show_stack+0x10/0x1c
    [<ffffffc0006d1e6c>] dump_stack+0x84/0xc8
    [<ffffffc0000b4568>] warn_slowpath_common+0x98/0xd0
    [<ffffffc0000b4664>] warn_slowpath_null+0x14/0x20
    [<ffffffc000170348>] vunmap_page_range+0x1c8/0x1d0
    [<ffffffc000170388>] unmap_kernel_range+0x20/0x88
    [<ffffffc000460ad0>] dma_common_free_remap+0x74/0x84
    [<ffffffc0000940d8>] __iommu_free_attrs+0x9c/0x178
    [<ffffffc0005032bc>] ehci_mem_cleanup+0x140/0x194
    [<ffffffc000503548>] ehci_stop+0x8c/0xdc
    [<ffffffc0004e8258>] usb_remove_hcd+0xf0/0x1cc
    [<ffffffc000516bc0>] host_stop+0x1c/0x58
    [<ffffffc000514240>] ci_otg_work+0xdc/0x120
    [<ffffffc0000c9c34>] process_one_work+0x134/0x33c
    [<ffffffc0000c9f78>] worker_thread+0x13c/0x47c
    [<ffffffc0000cf43c>] kthread+0xd8/0xf0
    "
    
    For dma_common_pages_remap:
    dma_common_pages_remap
       |->get_vm_area_caller
            |->__get_vm_area_node
                |->size = PAGE_ALIGN(size);   Round up to page aligned
    
    So, in dma_common_free_remap, we also need a page aligned size,
    pass 'PAGE_ALIGN(size)' to unmap_kernel_range.
    Signed-off-by: default avatarPeng Fan <van.freenix@gmail.com>
    Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
    1ccdc775
dma-mapping.c 8.19 KB