This is a note to let you know that I've just added the patch titled
android: binder: use VM_ALLOC to get vm area
to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
android-binder-use-vm_alloc-to-get-vm-area.patch
and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From aac6830ec1cb681544212838911cdc57f2638216 Mon Sep 17 00:00:00 2001
From: Ganesh Mahendran <opensource.ganesh@xxxxxxxxx>
Date: Wed, 10 Jan 2018 10:49:05 +0800
Subject: android: binder: use VM_ALLOC to get vm area
From: Ganesh Mahendran <opensource.ganesh@xxxxxxxxx>
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 <opensource.ganesh@xxxxxxxxx>
Acked-by: Martijn Coenen <maco@xxxxxxxxxxx>
Acked-by: Todd Kjos <tkjos@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/android/binder_alloc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -668,7 +668,7 @@ int binder_alloc_mmap_handler(struct bin
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";
Patches currently in stable-queue which might be from opensource.ganesh@xxxxxxxxx are
queue-4.14/android-binder-use-vm_alloc-to-get-vm-area.patch