On Sun, 2012-01-29 at 12:00 -0600, Larry Finger wrote: > On 01/29/2012 11:35 AM, Kalle Valo wrote: > > Larry Finger<Larry.Finger@xxxxxxxxxxxx> writes: > > > >> To all wireless developers: > >> > >> As you may have noticed, the udev layer is being changed. One of the > >> side effects is that the kernel may timeout when a driver uses > >> synchronous firmware loading. My rtlwifi drivers were affected, and a > >> kernel bugzilla has been logged against rtl8192se. I suggest that the > >> maintainers should be proactive, and convert to asynchronous loading > >> as soon as possible. > > > > Thanks for the summary, this was really useful. > > > >> In wireless-testing, the files listed below contain calls to > >> read_firmware() rather than read_firmware_nowait(): > >> > >> drivers/net/wireless/at76c50x-usb.c > >> drivers/net/wireless/ath/ath6kl/init.c > >> drivers/net/wireless/ath/ath9k/hif_usb.c > >> drivers/net/wireless/atmel.c > >> drivers/net/wireless/b43/main.c > >> drivers/net/wireless/b43legacy/main.c > >> drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c > >> drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c > >> drivers/net/wireless/ipw2x00/ipw2100.c > >> drivers/net/wireless/iwlegacy/3945-mac.c > >> drivers/net/wireless/iwlegacy/4965-mac.c > >> drivers/net/wireless/iwlwifi/iwl-agn.c > >> drivers/net/wireless/libertas/main.c > >> drivers/net/wireless/libertas/if_usb.c > >> drivers/net/wireless/libertas_tf/if_usb.c > >> drivers/net/wireless/mwifiex/main.c > >> drivers/net/wireless/mwl8k.c > >> drivers/net/wireless/orinoco/fw.c > >> drivers/net/wireless/orinoco/orinoco_usb.c > >> drivers/net/wireless/p54/p54spi.c > >> drivers/net/wireless/p54/p54usb.c > >> drivers/net/wireless/p54/p54pci.c > >> drivers/net/wireless/prism54/islpci_dev.c > >> drivers/net/wireless/rt2x00/rt2x00firmware.c > >> drivers/net/wireless/wl1251/main.c > >> drivers/net/wireless/zd1201.c > >> drivers/net/wireless/zd1211rw/zd_usb.c > >> > >> Some of the drivers above may be exempt as their firmware is built > >> into the kernel. I did not check for that case. > > > > But isn't the issue only when a firmware is requested synchronously > > during module init? For example, IIRC wl1251 loads the module during > > hw start and that should be safe, even when making a synchronous call. > > Or did I misunderstood something? > > As I understand the situation, if userland is running when the firmware is > requested synchronously, then the request should be OK. Certainly, when firmware > loading is triggered from the probe routine, it will cause trouble. > > I was just contacted this morning about problems with r8712u on Arch Linux. > Another driver for me to fix. I echo Kalle's thanks for this summary. As Kalle said, I think wl1251 is fine. It doesn't request any firmware during the probe path, only when the interface is brought up. In wl12xx, though, we have a problem. We request the *firmware* also when the interface is brought up, but we get the "NVS file" (which contains the MAC address) during probe. That must be fixed and is in my TODO list. -- Cheers, Luca. -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
