[lkml]   [2014]   [Oct]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [PATCH] staging: android: binder: move to the "real" part of the kernel
On Fri 2014-10-17 01:12:21, Greg Kroah-Hartman wrote:
> On Thu, Oct 16, 2014 at 10:09:04AM -0700, John Stultz wrote:
> > On Thu, Oct 16, 2014 at 5:47 AM, Greg Kroah-Hartman
> > <> wrote:
> > > From: Greg Kroah-Hartman <>

> > Are the Android guys comfortable with the ABI stability rules they'll
> > now face?
> Just because something is in staging, doesn't mean you don't have to
> follow the same ABI stability rules as the rest of the kernel. If a
> change had happened to this code that broke userspace in the past, I
> would have reverted it. So this should not be anything different from
> what has been happening inthe past.

Actually, there's big difference.

If Al Viro changes core filesystem in a way that breaks
staging/binder, binder is broken, and if it can't be fixed... well it
can't be fixed.

If Al Viro changes core filesystem in a way that breaks
drivers/binder, Al's change is going to be reverted.

It is really hard to review without API documentation. Normally, API
documentation is required for stuff like this.

For example: does it add new files in /proc?

Given that it is stable, can we get rid of binder_debug() and
especially BINDER_DEBUG_ENTRY stuff?

Checkpatch warns about 98 too long lines. Some of them could be fixed

This looks scary:

trace_binder_transaction_fd(t, fp->handle,
" fd %d -> %d\n",
fp->handle, target_fd);
/* TODO: fput? */
fp->handle = target_fd;
} break;

Could binder_transcation() be split to smaller functions according to
CodingStyle? 17 goto targets at the end of function are not exactly
easy to read.

ginder_thread_read/write also needs splitting.

binder_ioctl_write_read: just use direct return, no need to goto out
if it just returns.

proc->user_buffer_offset = vma->vm_start - (uintptr_t)proc->buffer;

if (cache_is_vipt_aliasing()) {
while (CACHE_COLOUR((vma->vm_start ^
(uint32_t)proc->buffer))) {

Should this be (uintptr_t)?

/*pr_info("binder_mmap: %d %lx-%lx maps %p\n",

Delete the code, don't comment it out. It is on more than one place.

static void print_binder_thread(struct seq_file *m,
struct binder_thread *thread,
int print_always)
struct binder_transaction *t;
struct binder_work *w;
size_t start_pos = m->count;
size_t header_pos;

seq_printf(m, " thread %d: l %02x\n", thread->pid,
header_pos = m->count;
t = thread->transaction_stack;
while (t) {
if (t->from == thread) {
outgoing transaction", t);
t = t->from_parent;

Is anyone depending on the debugfs files? Can it be deleted?

Code indentation is "interesting" in binder_thread_read(). See the "}
break;" lines. {}s should not be needed...?

I don't think this code would get merged if it was submitted for
normal inclusion in kernel. I don't think it is good idea to push it
through the back door, without documenting what it does and without
patches even going to the lists.


(cesky, pictures)

 \ /
  Last update: 2014-10-21 13:01    [W:0.105 / U:0.500 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site