2024-01-06 15:05:26

by Colin Ian King

Subject: [PATCH][next] binder: remove redundant variable page_addr

From: Colin Ian King <[email protected]>

Variable page_addr is being assigned a value that is never read. The
variable is redundant and can be removed.

Cleans up clang scan build warning:
warning: Value stored to 'page_addr' is never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <[email protected]>
---
drivers/android/binder_alloc.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
index ea5e1ba2d0d7..ed4ca6689c75 100644
--- a/drivers/android/binder_alloc.c
+++ b/drivers/android/binder_alloc.c
@@ -925,7 +925,6 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)
int i;

for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
- unsigned long page_addr;
bool on_lru;

if (!alloc->pages[i].page_ptr)
@@ -933,7 +932,6 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)

on_lru = list_lru_del_obj(&binder_freelist,
&alloc->pages[i].lru);
- page_addr = alloc->buffer + i * PAGE_SIZE;
binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
"%s: %d: page %d %s\n",
__func__, alloc->pid, i,
--
2.43.0

2024-01-06 16:30:20

by Carlos Llamas

Subject: Re: [PATCH][next] binder: remove redundant variable page_addr

On Sat, Jan 06, 2024 at 03:04:57PM +0000, Colin Ian King wrote:
> From: Colin Ian King <[email protected]>
>
> Variable page_addr is being assigned a value that is never read. The
> variable is redundant and can be removed.
>
> Cleans up clang scan build warning:
> warning: Value stored to 'page_addr' is never read [deadcode.DeadStores]
>
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/android/binder_alloc.c | 2 --
> 1 file changed, 2 deletions(-)
>
> diff --git a/drivers/android/binder_alloc.c b/drivers/android/binder_alloc.c
> index ea5e1ba2d0d7..ed4ca6689c75 100644
> --- a/drivers/android/binder_alloc.c
> +++ b/drivers/android/binder_alloc.c
> @@ -925,7 +925,6 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)
> int i;
>
> for (i = 0; i < alloc->buffer_size / PAGE_SIZE; i++) {
> - unsigned long page_addr;
> bool on_lru;
>
> if (!alloc->pages[i].page_ptr)
> @@ -933,7 +932,6 @@ void binder_alloc_deferred_release(struct binder_alloc *alloc)
>
> on_lru = list_lru_del_obj(&binder_freelist,
> &alloc->pages[i].lru);
> - page_addr = alloc->buffer + i * PAGE_SIZE;
> binder_alloc_debug(BINDER_DEBUG_BUFFER_ALLOC,
> "%s: %d: page %d %s\n",
> __func__, alloc->pid, i,
> --
> 2.43.0
>

Thanks Colin. I was waiting for this warning to hit mainline so that I
could add the following tags to the fix:

Fixes: 162c79731448 ("binder: avoid user addresses in debug logs")
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/

Feel free to take them for a v2 if you'd like. Either way,
Acked-by: Carlos Llamas <[email protected]>

--
Carlos Llamas