[BUG Fix Patch 1/6] Bug fix: Hold spinlock across find|remove /sys/firmware/memmap/X operation.
julian.calaby at gmail.com
Wed Jan 16 09:26:49 EST 2013
One minor point.
On Tue, Jan 15, 2013 at 9:54 PM, Tang Chen <tangchen at cn.fujitsu.com> wrote:
> It is unsafe to return an entry pointer and release the map_entries_lock. So we should
> not hold the map_entries_lock separately in firmware_map_find_entry() and
> firmware_map_remove_entry(). Hold the map_entries_lock across find and remove
> /sys/firmware/memmap/X operation.
> And also, users of these two functions need to be careful to hold the lock when using
> these two functions.
> The suggestion is from Andrew Morton <akpm at linux-foundation.org>
> Signed-off-by: Tang Chen <tangchen at cn.fujitsu.com>
> drivers/firmware/memmap.c | 25 +++++++++++++++++--------
> 1 files changed, 17 insertions(+), 8 deletions(-)
> diff --git a/drivers/firmware/memmap.c b/drivers/firmware/memmap.c
> index 4211da5..940c4e9 100644
> --- a/drivers/firmware/memmap.c
> +++ b/drivers/firmware/memmap.c
> @@ -188,23 +188,28 @@ static inline void remove_sysfs_fw_map_entry(struct firmware_map_entry *entry)
> - * Search memmap entry
> + * firmware_map_find_entry: Search memmap entry.
> + * @start: Start of the memory range.
> + * @end: End of the memory range (exclusive).
> + * @type: Type of the memory range.
> + *
> + * This function is to find the memmap entey of a given memory range.
> + * The caller must hold map_entries_lock, and must not release the lock
> + * until the processing of the returned entry has completed.
> + *
> + * Return pointer to the entry to be found on success, or NULL on failure.
Why not make this completely kernel-doc compliant as you're already
re-writing the comment?
Email: julian.calaby at gmail.com
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