Messages in this thread Patch in this message | | | From | Larry Finger <> | Subject | Re: [PATCH] Revert "staging:r8188eu: use lib80211 CCMP decrypt" | Date | Mon, 31 Dec 2018 20:17:33 -0600 |
| |
On 12/30/18 12:39 PM, Michael Straube wrote: > Commit 6bd082af7e36 ("staging:r8188eu: use lib80211 CCMP decrypt") > is causing hardfreeze whenever the driver tries to connect to my wifi > network. That makes the driver unusable on my system. Reverting the > commit fixes the issue and the driver works properly. > > Dec 29 19:21:17 gentoo kernel: BUG: scheduling while atomic: swapper/6/0/0x00000100
Michael,
I have verified the freezes that you see. Although I have not been able to capture the console dump, I think we are likely seeing the same problem.
I do have a work-around in that I have not gotten any freezes when I force module lib80211_crypt_ccmp to be loaded before I load module r8188eu. This clue was used in finding what seems to be a good fix.
I do not know anything about demand loading of modules using try_then_request_module(); however, I noticed that the macro actually calls __request_module(), which has the following comment:
* Load a module using the user mode module loader. The function returns * zero on success or a negative errno code or positive exit code from * "modprobe" on failure. Note that a successful module load does not mean * the module did not then unload and exit on an error of its own. Callers * must check that the service they requested is now available not blindly * invoke it.
I note that it says "user mode module loader". Routine rtw_aes_decrypt() is likely inside some sort of locking, which leads to the "scheduling while atomic" bug that you see. As a result, I suspect that the module is not loaded, and that leads to the NULL dereference when the module is accessed. Please try the one-line patch attached, which forces lib80211 to load when r8188eu is loaded. With this patch, I have been connected to an AES-encrypted AP for nearly 3 hours with no problems.
Larry
diff --git a/drivers/staging/rtl8188eu/core/rtw_security.c b/drivers/staging/rtl8188eu/core/rtw_security.c index f7407632e80b..052656a22821 100644 --- a/drivers/staging/rtl8188eu/core/rtw_security.c +++ b/drivers/staging/rtl8188eu/core/rtw_security.c @@ -1291,7 +1291,7 @@ u32 rtw_aes_decrypt(struct adapter *padapter, u8 *precvframe) struct sk_buff *skb = ((struct recv_frame *)precvframe)->pkt; void *crypto_private = NULL; u8 *key, *pframe = skb->data; - struct lib80211_crypto_ops *crypto_ops = try_then_request_module(lib80211_get_crypto_ops("CCMP"), "lib80211_crypt_ccmp"); + struct lib80211_crypto_ops *crypto_ops = lib80211_get_crypto_ops("CCMP"); struct security_priv *psecuritypriv = &padapter->securitypriv; char iv[8], icv[8]; | |