From: Marc Zyngier Date: Fri, 18 Mar 2011 03:53:58 +0000 (+0000) Subject: NET: smsc95xx: don't use stack for async writes to the device X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=3c0f3c605b2572c740f66ea39fe2d125399b20aa;p=openwrt%2Fstaging%2Fblogic.git NET: smsc95xx: don't use stack for async writes to the device The set_multicast operation performs asynchronous writes to the device, with some addresses pointing to the stack. Bad things may happen, and this is trapped CONFIG_DMA_API_DEBUG: [ 5.237762] WARNING: at /build/buildd/linux-linaro-omap-2.6.38/lib/dma-debug.c:867 check_for_stack+0xd4/0x100() [ 5.237792] ehci-omap ehci-omap.0: DMA-API: device driver maps memory fromstack [addr=d9c77dec] [ 5.237792] Modules linked in: smsc95xx(+) usbnet twl6030_usb twl4030_pwrbutton leds_gpio omap_wdt omap2_mcspi [ 5.237854] [] (unwind_backtrace+0x0/0xf8) from [] (warn_slowpath_common+0x54/0x64) [ 5.237884] [] (warn_slowpath_common+0x54/0x64) from [] (warn_slowpath_fmt+0x30/0x40) [ 5.237915] [] (warn_slowpath_fmt+0x30/0x40) from [] (check_for_stack+0xd4/0x100) [ 5.237915] [] (check_for_stack+0xd4/0x100) from [] (debug_dma_map_page+0xb4/0xdc) [ 5.237976] [] (debug_dma_map_page+0xb4/0xdc) from [] (map_urb_for_dma+0x26c/0x304) [ 5.237976] [] (map_urb_for_dma+0x26c/0x304) from [] (usb_hcd_submit_urb+0x78/0x19c) [ 5.238037] [] (usb_hcd_submit_urb+0x78/0x19c) from [] (smsc95xx_write_reg_async+0xb4/0x130 [smsc95xx]) [ 5.238067] [] (smsc95xx_write_reg_async+0xb4/0x130 [smsc95xx]) from [] (smsc95xx_set_multicast+0xfc/0x148 [smsc95xx]) [ 5.238098] [] (smsc95xx_set_multicast+0xfc/0x148 [smsc95xx]) from [] (smsc95xx_reset+0x2f8/0x68c [smsc95xx]) [ 5.238128] [] (smsc95xx_reset+0x2f8/0x68c [smsc95xx]) from [] (smsc95xx_bind+0xcc/0x188 [smsc95xx]) [ 5.238159] [] (smsc95xx_bind+0xcc/0x188 [smsc95xx]) from [] (usbnet_probe+0x204/0x4c4 [usbnet]) [ 5.238220] [] (usbnet_probe+0x204/0x4c4 [usbnet]) from [] (usb_probe_interface+0xe4/0x1c4) [ 5.238250] [] (usb_probe_interface+0xe4/0x1c4) from [] (really_probe+0x64/0x160) [ 5.238250] [] (really_probe+0x64/0x160) from [] (driver_probe_device+0x48/0x60) [ 5.238281] [] (driver_probe_device+0x48/0x60) from [] (__driver_attach+0x8c/0x90) [ 5.238311] [] (__driver_attach+0x8c/0x90) from [] (bus_for_each_dev+0x50/0x7c) [ 5.238311] [] (bus_for_each_dev+0x50/0x7c) from [] (bus_add_driver+0x190/0x250) [ 5.238311] [] (bus_add_driver+0x190/0x250) from [] (driver_register+0x78/0x13c) [ 5.238433] [] (driver_register+0x78/0x13c) from [] (usb_register_driver+0x78/0x13c) [ 5.238464] [] (usb_register_driver+0x78/0x13c) from [] (do_one_initcall+0x34/0x188) [ 5.238494] [] (do_one_initcall+0x34/0x188) from [] (sys_init_module+0xb0/0x1c0) [ 5.238525] [] (sys_init_module+0xb0/0x1c0) from [] (ret_fast_syscall+0x0/0x30) Move the two offenders to the private structure which is kmalloc-ed, and thus safe. Signed-off-by: Marc Zyngier Cc: Steve Glendinning Signed-off-by: David S. Miller --- diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c index bc86f4b6ecc2..727874d9deb6 100644 --- a/drivers/net/usb/smsc95xx.c +++ b/drivers/net/usb/smsc95xx.c @@ -49,6 +49,8 @@ struct smsc95xx_priv { u32 mac_cr; + u32 hash_hi; + u32 hash_lo; spinlock_t mac_cr_lock; bool use_tx_csum; bool use_rx_csum; @@ -370,10 +372,11 @@ static void smsc95xx_set_multicast(struct net_device *netdev) { struct usbnet *dev = netdev_priv(netdev); struct smsc95xx_priv *pdata = (struct smsc95xx_priv *)(dev->data[0]); - u32 hash_hi = 0; - u32 hash_lo = 0; unsigned long flags; + pdata->hash_hi = 0; + pdata->hash_lo = 0; + spin_lock_irqsave(&pdata->mac_cr_lock, flags); if (dev->net->flags & IFF_PROMISC) { @@ -394,13 +397,13 @@ static void smsc95xx_set_multicast(struct net_device *netdev) u32 bitnum = smsc95xx_hash(ha->addr); u32 mask = 0x01 << (bitnum & 0x1F); if (bitnum & 0x20) - hash_hi |= mask; + pdata->hash_hi |= mask; else - hash_lo |= mask; + pdata->hash_lo |= mask; } netif_dbg(dev, drv, dev->net, "HASHH=0x%08X, HASHL=0x%08X\n", - hash_hi, hash_lo); + pdata->hash_hi, pdata->hash_lo); } else { netif_dbg(dev, drv, dev->net, "receive own packets only\n"); pdata->mac_cr &= @@ -410,8 +413,8 @@ static void smsc95xx_set_multicast(struct net_device *netdev) spin_unlock_irqrestore(&pdata->mac_cr_lock, flags); /* Initiate async writes, as we can't wait for completion here */ - smsc95xx_write_reg_async(dev, HASHH, &hash_hi); - smsc95xx_write_reg_async(dev, HASHL, &hash_lo); + smsc95xx_write_reg_async(dev, HASHH, &pdata->hash_hi); + smsc95xx_write_reg_async(dev, HASHL, &pdata->hash_lo); smsc95xx_write_reg_async(dev, MAC_CR, &pdata->mac_cr); }