Messages in this thread | | | Date | Mon, 22 Jan 2018 16:54:28 +0100 | From | Greg KH <> | Subject | Re: [PATCH v3] android: binder: use VM_ALLOC to get vm area |
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On Wed, Jan 10, 2018 at 10:49:05AM +0800, Ganesh Mahendran wrote: > 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 <opensource.ganesh@gmail.com> > ---- > V3: update comments > V2: update comments > --- > drivers/android/binder_alloc.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-)
Martijn and Todd, any objections to this patch?
thanks,
greg k-h
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