linux/drivers/base/firmware_class.c, branch v3.8

firmware: make sure the fw file size is not 0

2013-01-16T17:09:53Z

If the requested firmware file size is 0 bytes in the filesytem, we will try to vmalloc(0), which causes a warning: vmalloc: allocation failure: 0 bytes kworker/1:1: page allocation failure: order:0, mode:0xd2 __vmalloc_node_range+0x164/0x208 __vmalloc_node+0x4c/0x58 vmalloc+0x38/0x44 _request_firmware_load+0x220/0x6b0 request_firmware+0x64/0xc8 wl18xx_setup+0xb4/0x570 [wl18xx] wlcore_nvs_cb+0x64/0x9f8 [wlcore] request_firmware_work_func+0x94/0x100 process_one_work+0x1d0/0x750 worker_thread+0x184/0x4ac kthread+0xb4/0xc0 To fix this, check whether the file size is less than or equal to zero in fw_read_file_contents(). Cc: stable [3.7] Signed-off-by: Luciano Coelho Acked-by: Ming Lei Signed-off-by: Linus Torvalds

firmware loader: document firmware cache mechanism

2012-11-14T23:07:18Z

This patch documents the firmware cache mechanism so that users of request_firmware() know that it can be called safely inside device's suspend and resume callback, and the device's firmware needn't be cached any more by individual driver itself to deal with firmware loss during system resume. Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman

firmware loader: introduce module parameter to customize(v4) fw search path

2012-11-14T23:07:18Z

This patch introduces one module parameter of 'path' in firmware_class to support customizing firmware image search path, so that people can use its own firmware path if the default built-in paths can't meet their demand[1], and the typical usage is passing the below from kernel command parameter when 'firmware_class' is built in kernel: firmware_class.path=$CUSTOMIZED_PATH [1], https://lkml.org/lkml/2012/10/11/337 Cc: Linus Torvalds Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman

firmware: use noinline_for_stack

2012-11-14T23:05:05Z

The comment above fw_file_size() suggests it is noinline for stack size reasons. Use noinline_for_stack to make this more clear. Signed-off-by: Cesar Eduardo Barros Acked-by: Ming Lei Signed-off-by: Greg Kroah-Hartman

firmware loader: Fix the concurrent request_firmware() race for kref_get/put

2012-11-14T23:04:23Z

There is one race that both request_firmware() with the same firmware name. The race scenerio is as below: CPU1 CPU2 request_firmware() --> _request_firmware_load() return err another request_firmware() is coming --> _request_firmware_cleanup is called --> _request_firmware_prepare --> release_firmware ---> fw_lookup_and_allocate_buf --> spin_lock(&fwc->lock) ... __fw_lookup_buf() return true fw_free_buf() will be called --> ... kref_put --> decrease the refcount to 0 kref_get(&tmp->ref) ==> it will trigger warning due to refcount == 0 __fw_free_buf() --> ... spin_unlock(&fwc->lock) spin_lock(&fwc->lock) list_del(&buf->list) spin_unlock(&fwc->lock) kfree(buf) After that, the freed buf will be used. The key race is decreasing refcount to 0 and list_del is not protected together by fwc->lock, and it is possible another thread try to get it between refcount==0 and list_del. Fix it here to protect it together. Acked-by: Ming Lei Signed-off-by: liu chuansheng Cc: stable Signed-off-by: Greg Kroah-Hartman

firmware loader: Fix the race FW_STATUS_DONE is followed by class_timeout

2012-11-14T23:04:23Z

There is a race as below when calling request_firmware(): CPU1 CPU2 write 0 > loading mutex_lock(&fw_lock) ... set_bit FW_STATUS_DONE class_timeout is coming set_bit FW_STATUS_ABORT complete_all &completion ... mutex_unlock(&fw_lock) In this time, the bit FW_STATUS_DONE and FW_STATUS_ABORT are set, and request_firmware() will return failure due to condition in _request_firmware_load(): if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status)) retval = -ENOENT; But from the above scenerio, it should be a successful requesting. So we need judge if the bit FW_STATUS_DONE is already set before calling fw_load_abort() in timeout function. As Ming's proposal, we need change the timer into sched_work to benefit from using &fw_lock mutex also. Signed-off-by: liu chuansheng Acked-by: Ming Lei Cc: stable Signed-off-by: Greg Kroah-Hartman

firmware loader: sync firmware cache by async_synchronize_full_domain

2012-10-22T15:37:18Z

async.c has provided synchronization mechanism on async_schedule_*, so use async_synchronize_full_domain to sync caching firmware instead of reinventing the wheel. Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman

firmware loader: let direct loading back on 'firmware_buf'

2012-10-22T15:37:17Z

Firstly 'firmware_buf' is introduced to make all loading requests to share one firmware kernel buffer, so firmware_buf should be used in direct loading for saving memory and speedup firmware loading. Secondly, the commit below abb139e75c2cdbb955e840d6331cb5863e409d0e(firmware:teach the kernel to load firmware files directly from the filesystem) introduces direct loading for fixing udev regression, but it bypasses the firmware cache meachnism, so this patch enables caching firmware for direct loading case since it is still needed to solve drivers' dependency during system resume. Cc: Linus Torvalds Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman

firmware loader: fix one reqeust_firmware race

2012-10-22T15:37:17Z

Several loading requests may be pending on one same firmware buf, and this patch moves fw_map_pages_buf() before complete_all(&fw_buf->completion) and let all requests see the mapped 'buf->data' once the loading is completed. Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman

firmware loader: cancel uncache work before caching firmware

2012-10-22T15:37:16Z

Under 'Opportunistic sleep' situation, system sleep might be triggered very frequently, so the uncahce work may not be completed before caching firmware during next suspend. This patch cancels the uncache work before caching firmware to fix the problem above. Also this patch optimizes the cacheing firmware mechanism a bit by only storing one firmware cache entry for one firmware image. So if the firmware is still cached during suspend, it doesn't need to be loaded from user space any more. Signed-off-by: Ming Lei Signed-off-by: Greg Kroah-Hartman