2015-12-02 04:18:26

by Brent Taylor

Subject: [v2] ath6kl: Use vmalloc to allocate ar->fw for api1 method

Since commit 8437754c8335 ("ath6kl: Use vmalloc instead of kmalloc for
fw") ar->fw is expected to be pointing to memory allocated by vmalloc.
If the api1 method (via ath6kl_fetch_fw_api1) is used to allocate memory
for ar->fw, then kmemdup is used. This patch checks if the firmware being
loaded is the 'fw' image, then use vmalloc, otherwise use kmalloc.

Signed-off-by: Brent Taylor <[email protected]>
---
v2: Fix commit message and code formatting (use tab instaed of spaces)

drivers/net/wireless/ath/ath6kl/init.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath6kl/init.c b/drivers/net/wireless/ath/ath6kl/init.c
index 6ae0734..4f16bd8 100644
--- a/drivers/net/wireless/ath/ath6kl/init.c
+++ b/drivers/net/wireless/ath/ath6kl/init.c
@@ -673,10 +673,15 @@ static int ath6kl_get_fw(struct ath6kl *ar, const char *filename,
return ret;

*fw_len = fw_entry->size;
- *fw = kmemdup(fw_entry->data, fw_entry->size, GFP_KERNEL);
+ if (&ar->fw == fw)
+ *fw = vmalloc(fw_entry->size);
+ else
+ *fw = kmalloc(fw_entry->size, GFP_KERNEL);

if (*fw == NULL)
ret = -ENOMEM;
+ else
+ memcpy(*fw, fw_entry->data, fw_entry->size);

release_firmware(fw_entry);

--
2.6.3

2015-12-02 13:20:36

by Eric Dumazet

Subject: Re: [v2] ath6kl: Use vmalloc to allocate ar->fw for api1 method

On Tue, 2015-12-01 at 22:18 -0600, Brent Taylor wrote:
> Since commit 8437754c8335 ("ath6kl: Use vmalloc instead of kmalloc for
> fw") ar->fw is expected to be pointing to memory allocated by vmalloc.
> If the api1 method (via ath6kl_fetch_fw_api1) is used to allocate memory
> for ar->fw, then kmemdup is used. This patch checks if the firmware being
> loaded is the 'fw' image, then use vmalloc, otherwise use kmalloc.
>
> Signed-off-by: Brent Taylor <[email protected]>
> ---
> v2: Fix commit message and code formatting (use tab instaed of spaces)
>
> drivers/net/wireless/ath/ath6kl/init.c | 7 ++++++-
> 1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/ath6kl/init.c b/drivers/net/wireless/ath/ath6kl/init.c
> index 6ae0734..4f16bd8 100644
> --- a/drivers/net/wireless/ath/ath6kl/init.c
> +++ b/drivers/net/wireless/ath/ath6kl/init.c
> @@ -673,10 +673,15 @@ static int ath6kl_get_fw(struct ath6kl *ar, const char *filename,
> return ret;
>
> *fw_len = fw_entry->size;
> - *fw = kmemdup(fw_entry->data, fw_entry->size, GFP_KERNEL);
> + if (&ar->fw == fw)
> + *fw = vmalloc(fw_entry->size);
> + else
> + *fw = kmalloc(fw_entry->size, GFP_KERNEL);
>
> if (*fw == NULL)
> ret = -ENOMEM;
> + else
> + memcpy(*fw, fw_entry->data, fw_entry->size);
>
> release_firmware(fw_entry);
>

This looks very odd.

Why not using kvfree() in ath6kl_core_cleanup() ?

If you switch to vmalloc() here because the kmemdup() was potentially
failing, then the changelog should say it !

Using vmalloc() instead of kmalloc() should be driven by the allocation
size, not the legacy code doing the freeing.