From 85714108e673cdebf1b96abfd50fb02a29e37577 Mon Sep 17 00:00:00 2001 From: Peng Fan Date: Thu, 21 Jul 2016 16:04:21 +0800 Subject: [PATCH] drivers: base: dma-mapping: page align the size when unmap_kernel_range 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: [] dump_backtrace+0x0/0x124 [] show_stack+0x10/0x1c [] dump_stack+0x84/0xc8 [] warn_slowpath_common+0x98/0xd0 [] warn_slowpath_null+0x14/0x20 [] vunmap_page_range+0x1c8/0x1d0 [] unmap_kernel_range+0x20/0x88 [] dma_common_free_remap+0x74/0x84 [] __iommu_free_attrs+0x9c/0x178 [] ehci_mem_cleanup+0x140/0x194 [] ehci_stop+0x8c/0xdc [] usb_remove_hcd+0xf0/0x1cc [] host_stop+0x1c/0x58 [] ci_otg_work+0xdc/0x120 [] process_one_work+0x134/0x33c [] worker_thread+0x13c/0x47c [] 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: Peng Fan Cc: Greg Kroah-Hartman Cc: Signed-off-by: Greg Kroah-Hartman --- drivers/base/dma-mapping.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c index d799662f19eb..261420ddfe66 100644 --- a/drivers/base/dma-mapping.c +++ b/drivers/base/dma-mapping.c @@ -334,7 +334,7 @@ void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags) return; } - unmap_kernel_range((unsigned long)cpu_addr, size); + unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size)); vunmap(cpu_addr); } #endif