From 09164043f63c947a49797750a09ca1cd7c31108e Mon Sep 17 00:00:00 2001 From: Larry Finger Date: Sun, 12 Jan 2014 15:11:37 -0600 Subject: b43: Fix lockdep splat In https://bugzilla.kernel.org/show_bug.cgi?id=67561, a locking dependency is reported when b43 is used with hostapd, and rfkill is used to kill the radio output. The lockdep splat (in part) is as follows: ====================================================== [ INFO: possible circular locking dependency detected ] 3.12.0 #1 Not tainted ------------------------------------------------------- rfkill/10040 is trying to acquire lock: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x12/0x20 but task is already holding lock: (rfkill_global_mutex){+.+.+.}, at: [] rfkill_fop_write+0x6a/0x170 [rfkill] --snip-- Chain exists of: rtnl_mutex --> misc_mtx --> rfkill_global_mutex The fix is to move the initialization of the hardware random number generator outside the code range covered by the rtnl_mutex. Reported-by: yury Tested-by: yury Signed-off-by: Larry Finger Cc: Stable Signed-off-by: John W. Linville --- drivers/net/wireless/b43/main.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'drivers/net/wireless/b43/main.c') diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c index ccd24f0acb8d..86b2030055d2 100644 --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -2424,6 +2424,7 @@ error: static int b43_one_core_attach(struct b43_bus_dev *dev, struct b43_wl *wl); static void b43_one_core_detach(struct b43_bus_dev *dev); +static int b43_rng_init(struct b43_wl *wl); static void b43_request_firmware(struct work_struct *work) { @@ -2475,6 +2476,10 @@ start_ieee80211: goto err_one_core_detach; wl->hw_registred = true; b43_leds_register(wl->current_dev); + + /* Register HW RNG driver */ + b43_rng_init(wl); + goto out; err_one_core_detach: @@ -4636,9 +4641,6 @@ static void b43_wireless_core_exit(struct b43_wldev *dev) if (!dev || b43_status(dev) != B43_STAT_INITIALIZED) return; - /* Unregister HW RNG driver */ - b43_rng_exit(dev->wl); - b43_set_status(dev, B43_STAT_UNINIT); /* Stop the microcode PSM. */ @@ -4795,9 +4797,6 @@ static int b43_wireless_core_init(struct b43_wldev *dev) b43_set_status(dev, B43_STAT_INITIALIZED); - /* Register HW RNG driver */ - b43_rng_init(dev->wl); - out: return err; @@ -5464,6 +5463,9 @@ static void b43_bcma_remove(struct bcma_device *core) b43_one_core_detach(wldev->dev); + /* Unregister HW RNG driver */ + b43_rng_exit(wl); + b43_leds_unregister(wl); ieee80211_free_hw(wl->hw); @@ -5541,6 +5543,9 @@ static void b43_ssb_remove(struct ssb_device *sdev) b43_one_core_detach(dev); + /* Unregister HW RNG driver */ + b43_rng_exit(wl); + if (list_empty(&wl->devlist)) { b43_leds_unregister(wl); /* Last core on the chip unregistered. -- cgit v1.2.3 From 0673effd41dba323d6a280ef37b5ef29f3f5a653 Mon Sep 17 00:00:00 2001 From: Larry Finger Date: Sun, 12 Jan 2014 15:11:38 -0600 Subject: b43: Fix unload oops if firmware is not available The asyncronous firmware load uses a completion struct to hold firmware processing until the user-space routines are up and running. There is. however, a problem in that the waiter is nevered canceled during teardown. As a result, unloading the driver when firmware is not available causes an oops. To be able to access the completion structure at teardown, it had to be moved into the b43_wldev structure. This patch also fixes a typo in a comment. Signed-off-by: Larry Finger Cc: Stable Signed-off-by: John W. Linville --- drivers/net/wireless/b43/b43.h | 4 ++-- drivers/net/wireless/b43/main.c | 10 +++++----- 2 files changed, 7 insertions(+), 7 deletions(-) (limited to 'drivers/net/wireless/b43/main.c') diff --git a/drivers/net/wireless/b43/b43.h b/drivers/net/wireless/b43/b43.h index 7f3d461f7e8d..54376fddfaf9 100644 --- a/drivers/net/wireless/b43/b43.h +++ b/drivers/net/wireless/b43/b43.h @@ -731,8 +731,6 @@ enum b43_firmware_file_type { struct b43_request_fw_context { /* The device we are requesting the fw for. */ struct b43_wldev *dev; - /* a completion event structure needed if this call is asynchronous */ - struct completion fw_load_complete; /* a pointer to the firmware object */ const struct firmware *blob; /* The type of firmware to request. */ @@ -809,6 +807,8 @@ enum { struct b43_wldev { struct b43_bus_dev *dev; struct b43_wl *wl; + /* a completion event structure needed if this call is asynchronous */ + struct completion fw_load_complete; /* The device initialization status. * Use b43_status() to query. */ diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c index 86b2030055d2..c75237eb55a1 100644 --- a/drivers/net/wireless/b43/main.c +++ b/drivers/net/wireless/b43/main.c @@ -2070,6 +2070,7 @@ void b43_do_release_fw(struct b43_firmware_file *fw) static void b43_release_firmware(struct b43_wldev *dev) { + complete(&dev->fw_load_complete); b43_do_release_fw(&dev->fw.ucode); b43_do_release_fw(&dev->fw.pcm); b43_do_release_fw(&dev->fw.initvals); @@ -2095,7 +2096,7 @@ static void b43_fw_cb(const struct firmware *firmware, void *context) struct b43_request_fw_context *ctx = context; ctx->blob = firmware; - complete(&ctx->fw_load_complete); + complete(&ctx->dev->fw_load_complete); } int b43_do_request_fw(struct b43_request_fw_context *ctx, @@ -2142,7 +2143,7 @@ int b43_do_request_fw(struct b43_request_fw_context *ctx, } if (async) { /* do this part asynchronously */ - init_completion(&ctx->fw_load_complete); + init_completion(&ctx->dev->fw_load_complete); err = request_firmware_nowait(THIS_MODULE, 1, ctx->fwname, ctx->dev->dev->dev, GFP_KERNEL, ctx, b43_fw_cb); @@ -2150,12 +2151,11 @@ int b43_do_request_fw(struct b43_request_fw_context *ctx, pr_err("Unable to load firmware\n"); return err; } - /* stall here until fw ready */ - wait_for_completion(&ctx->fw_load_complete); + wait_for_completion(&ctx->dev->fw_load_complete); if (ctx->blob) goto fw_ready; /* On some ARM systems, the async request will fail, but the next sync - * request works. For this reason, we dall through here + * request works. For this reason, we fall through here */ } err = request_firmware(&ctx->blob, ctx->fwname, -- cgit v1.2.3