On 16.06.2013 13:35, Jussi Kivilinna wrote: > On 16.06.2013 11:21, Oliver Neukum wrote: >> On Saturday 15 June 2013 16:22:30 Jussi Kivilinna wrote: >> >>> Hm.. rethink this a bit. >>> >>> Transfer buffer might be dma aligned but shorter than cacheline and end of cacheline >>> used as something else. Manual alignment by host driver does not catch that >>> or fix that. >>> So, yes.. dma mapping should work with unaligned buffers, but maybe the actual >>> problem is multiple buffers from same cacheline. >> >> The buffers kmalloc() returns are OK in that regard. A driver that uses >> a buffer for anything but buffering is buggy. > > Ok, I'll look at that direction. Thanks. > So if I understood correctly, drivers that allocate these as part of larger structures (struct *_device etc) are doing wrong thing and are potentially buggy. And this is because cachelines of buffers can be DMA mapped after usb_submit_urb() and editing same cacheline while URB is in-flight can therefore be hazardous. I checked setup_packet and transfer_buffer usage of some drivers in 3.9.8 and made some observations. Should these be fixed? URB setup_packet and transfer_buffer part of same structure (might share same cacheline for same URB): * iforce: - http://lxr.linux.no/linux+v3.9.8/drivers/input/joystick/iforce/iforce-usb.c#L173 - http://lxr.linux.no/linux+v3.9.8/drivers/input/joystick/iforce/iforce.h#L101 * usbvision: - http://lxr.linux.no/linux+v3.9.8/drivers/media/usb/usbvision/usbvision-core.c#L1445 - http://lxr.linux.no/linux+v3.9.8/drivers/media/usb/usbvision/usbvision.h#L366 * catc: - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/catc.c#L499 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/catc.c#L500 - ctrl_buf, ctrl_dr: http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/catc.c#L162 * rtl8150: - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/rtl8150.c#L200 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/rtl8150.c#L128 * rt2x000usb: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rt2x00/rt2x00usb.c#L212 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rt2x00/rt2x00usb.c#L169 * rtl8187: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rtl818x/rtl8187/dev.c#L156 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rtl818x/rtl8187/dev.c#L130 * uss720: - http://lxr.linux.no/linux+v3.9.8/drivers/usb/misc/uss720.c#L176 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/misc/uss720.c#L72 URB transfer_buffer array (transfer buffers preloaded as array, element size less than cacheline): * rtlwifi: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rtlwifi/usb.c#L152 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rtlwifi/wifi.h#L1859 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rtlwifi/usb.c#L980 * catc: - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/catc.c#L371 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/catc.c#L162 URB setup_packet part of larger structure: * gigaset: - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/gigaset/bas-gigaset.c#L90 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/gigaset/bas-gigaset.c#L581 * mISDN/hfcsusb: - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hardware/mISDN/hfcsusb.c#L1732 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hardware/mISDN/hfcsusb.c#L74 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hardware/mISDN/hfcsusb.h#L270 * hisax/hfc_usb: - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/hfc_usb.c#L1185 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/hfc_usb.c#L227 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/hfc_usb.c#L193 * hisax/st5481: - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/st5481_usb.c#L42 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/st5481.h#L326 * hso: - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/hso.c#L1812 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/hso.c#L1846 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/hso.c#L220 * pegasus: - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/pegasus.c#L169 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/pegasus.h#L111 * brcmfmac: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/brcm80211/brcmfmac/usb.c#L209 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/brcm80211/brcmfmac/usb.c#L71 * staging/vt6656: - http://lxr.linux.no/linux+v3.9.8/drivers/staging/vt6656/usbpipe.c#L142 - http://lxr.linux.no/linux+v3.9.8/drivers/staging/vt6656/device.h#L390 URB transfer_buffer part of larger structure: * iforce: - http://lxr.linux.no/linux+v3.9.8/drivers/input/joystick/iforce/iforce-usb.c#L170 - http://lxr.linux.no/linux+v3.9.8/drivers/input/joystick/iforce/iforce-usb.c#L167 - http://lxr.linux.no/linux+v3.9.8/drivers/input/joystick/iforce/iforce.h#L101 - http://lxr.linux.no/linux+v3.9.8/drivers/input/joystick/iforce/iforce-usb.c#L147 * ks959: - http://lxr.linux.no/linux+v3.9.8/drivers/net/irda/ks959-sir.c#L278 - http://lxr.linux.no/linux+v3.9.8/drivers/net/irda/ks959-sir.c#L172 * ksdazzle-sir: - http://lxr.linux.no/linux+v3.9.8/drivers/net/irda/ksdazzle-sir.c#L199 - http://lxr.linux.no/linux+v3.9.8/drivers/net/irda/ksdazzle-sir.c#L138 * wusbcore: - http://lxr.linux.no/linux+v3.9.8/drivers/usb/wusbcore/security.c#L568 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/wusbcore/wusbhc.h#L288 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/wusbcore/wa-xfer.c#L378 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/wusbcore/wa-xfer.c#L337 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/wusbcore/wa-xfer.c#L661 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/wusbcore/wa-xfer.c#L115 * mISDN/hfcsusb: - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hardware/mISDN/hfcsusb.c#L1515 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hardware/mISDN/hfcsusb.h#L247 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hardware/mISDN/hfcsusb.c#L1071 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hardware/mISDN/hfcsusb.h#L236 * hisax/hfc_usb: - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/hfc_usb.c#L924 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/hfc_usb.c#L148 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/hfc_usb.c#L591 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/hisax/hfc_usb.c#L144 * rc/imon: - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/imon.c#L480 - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/imon.c#L504 - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/imon.c#L2148 - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/imon.c#L2232 - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/imon.c#L2452 - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/imon.c#L2462 - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/imon.c#L90 * catc: - tx_buf, rx_buf, irq_buf: http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/catc.c#L162 * hso: - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/hso.c#L1464 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/hso.c#L208 * pegasus: - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/pegasus.c#L1030 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/pegasus.h#L111 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/pegasus.c#L886 - http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/pegasus.h#L107 * brcmfmac: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/brcm80211/brcmfmac/usb.c#L631 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/brcm80211/brcmfmac/usb.c#L71 * staging/bcm: - http://lxr.linux.no/linux+v3.9.8/drivers/staging/bcm/InterfaceIsr.c#L125 - http://lxr.linux.no/linux+v3.9.8/drivers/staging/bcm/InterfaceAdapter.h#L63 * speedtch: - http://lxr.linux.no/linux+v3.9.8/drivers/usb/atm/speedtch.c#L888 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/atm/speedtch.c#L137 * gigaset: - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/gigaset/usb-gigaset.c#L467 - http://lxr.linux.no/linux+v3.9.8/drivers/isdn/gigaset/gigaset.h#L521 * ttusbir: - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/ttusbir.c#L300 - http://lxr.linux.no/linux+v3.9.8/drivers/media/rc/ttusbir.c#L48 * vub300: - http://lxr.linux.no/linux+v3.9.8/drivers/mmc/host/vub300.c#L467 - http://lxr.linux.no/linux+v3.9.8/drivers/mmc/host/vub300.c#L346 - http://lxr.linux.no/linux+v3.9.8/drivers/mmc/host/vub300.c#L491 - http://lxr.linux.no/linux+v3.9.8/drivers/mmc/host/vub300.c#L345 - http://lxr.linux.no/linux+v3.9.8/drivers/mmc/host/vub300.c#L1526 - http://lxr.linux.no/linux+v3.9.8/drivers/mmc/host/vub300.c#L355 * mcs7780: - http://lxr.linux.no/linux+v3.9.8/drivers/net/irda/mcs7780.c#L519 - http://lxr.linux.no/linux+v3.9.8/drivers/net/irda/mcs7780.c#L844 - http://lxr.linux.no/linux+v3.9.8/drivers/net/irda/mcs7780.h#L103 * rt2x00usb: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rt2x00/rt2500usb.c#L1194 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rt2x00/rt2x00usb.h#L387 * rtl8187: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rtl818x/rtl8187/dev.c#L551 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/rtl818x/rtl8187/rtl8187.h#L142 * zd1201: - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/zd1201.c#L817 - http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/zd1201.h#L42 * quatech2: - http://lxr.linux.no/linux+v3.9.8/drivers/usb/serial/quatech2.c#L769 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/serial/quatech2.c#L111 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/serial/quatech2.c#L841 - http://lxr.linux.no/linux+v3.9.8/drivers/usb/serial/quatech2.c#L118 * caiaq: - http://lxr.linux.no/linux+v3.9.8/sound/usb/caiaq/device.c#L425 - http://lxr.linux.no/linux+v3.9.8/sound/usb/caiaq/device.c#L430 - http://lxr.linux.no/linux+v3.9.8/sound/usb/caiaq/device.h#L77 - http://lxr.linux.no/linux+v3.9.8/sound/usb/caiaq/device.h#L79 URB transfer buffer in stack: * alauda: - command: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L226 - command: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L210 - command: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L291 - command: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L275 - command: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L342 - command: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L325 - command: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L165 - oob: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L230 - oob: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L377 - oob: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L401 - oob: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L467 - oob: http://lxr.linux.no/linux+v3.9.8/drivers/mtd/nand/alauda.c#L295 * pn533: - ack: http://lxr.linux.no/linux+v3.9.8/drivers/nfc/pn533.c#L630 * i2c-tiny-usb: - func: http://lxr.linux.no/linux+v3.9.8/drivers/i2c/busses/i2c-tiny-usb.c#L116 - func: http://lxr.linux.no/linux+v3.9.8/drivers/i2c/busses/i2c-tiny-usb.c#L159 * zd1201: - ret: http://lxr.linux.no/linux+v3.9.8/drivers/net/wireless/zd1201.c#L100 * rndis_host: - notification: http://lxr.linux.no/linux+v3.9.8/drivers/net/usb/rndis_host.c#L143 * 6fire: - buffer: http://lxr.linux.no/linux+v3.9.8/sound/usb/6fire/comm.c#L113 - buffer: http://lxr.linux.no/linux+v3.9.8/sound/usb/6fire/comm.c#L122 - send_buffer: http://lxr.linux.no/linux+v3.9.8/sound/usb/6fire/comm.c#L96 -Jussi -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
