3.16.57-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Ganesh Mahendran <[email protected]> commit aac6830ec1cb681544212838911cdc57f2638216 upstream. VM_IOREMAP is used to access hardware through a mechanism called I/O mapped memory. Android binder is a IPC machanism which will not access I/O memory. And VM_IOREMAP has alignment requiement which may not needed in binder. __get_vm_area_node() { ... if (flags & VM_IOREMAP) align = 1ul << clamp_t(int, fls_long(size), PAGE_SHIFT, IOREMAP_MAX_ORDER); ... } This patch will save some kernel vm area, especially for 32bit os. In 32bit OS, kernel vm area is only 240MB. We may got below error when launching a app: <3>[ 4482.440053] binder_alloc: binder_alloc_mmap_handler: 15728 8ce67000-8cf65000 get_vm_area failed -12 <3>[ 4483.218817] binder_alloc: binder_alloc_mmap_handler: 15745 8ce67000-8cf65000 get_vm_area failed -12 Signed-off-by: Ganesh Mahendran <[email protected]> Acked-by: Martijn Coenen <[email protected]> Acked-by: Todd Kjos <[email protected]> ---- V3: update comments V2: update comments Signed-off-by: Greg Kroah-Hartman <[email protected]> [bwh: Backported to 3.16: adjust filename] Signed-off-by: Ben Hutchings <[email protected]> --- drivers/staging/android/binder.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/staging/android/binder.c +++ b/drivers/staging/android/binder.c @@ -2808,7 +2808,7 @@ static int binder_mmap(struct file *filp goto err_already_mapped; } - area = get_vm_area(vma->vm_end - vma->vm_start, VM_IOREMAP); + area = get_vm_area(vma->vm_end - vma->vm_start, VM_ALLOC); if (area == NULL) { ret = -ENOMEM; failure_string = "get_vm_area";
