From 7d3510356b066bcfa9898ec3f90c9c7810ba6ed7 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 11 Aug 2010 23:04:31 -0600 Subject: [PATCH] param: lock myri10ge_fw_name against sysfs changes. Since it can be changed via sysfs, we need to make a copy. This most generic way of doing this is to keep a flag so we know when to free it. Signed-off-by: Rusty Russell Reviewed-by: Takashi Iwai Cc: Andrew Gallatin Cc: Brice Goglin Cc: netdev@vger.kernel.org --- drivers/net/myri10ge/myri10ge.c | 54 +++++++++++++++++++++++++-------- 1 file changed, 41 insertions(+), 13 deletions(-) diff --git a/drivers/net/myri10ge/myri10ge.c b/drivers/net/myri10ge/myri10ge.c index d771d1650d60..fb2c0927d3cc 100644 --- a/drivers/net/myri10ge/myri10ge.c +++ b/drivers/net/myri10ge/myri10ge.c @@ -239,6 +239,7 @@ struct myri10ge_priv { int watchdog_resets; int watchdog_pause; int pause; + bool fw_name_allocated; char *fw_name; char eeprom_strings[MYRI10GE_EEPROM_STRINGS_SIZE]; char *product_code_string; @@ -271,6 +272,7 @@ MODULE_FIRMWARE("myri10ge_eth_z8e.dat"); MODULE_FIRMWARE("myri10ge_rss_ethp_z8e.dat"); MODULE_FIRMWARE("myri10ge_rss_eth_z8e.dat"); +/* Careful: must be accessed under kparam_block_sysfs_write */ static char *myri10ge_fw_name = NULL; module_param(myri10ge_fw_name, charp, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(myri10ge_fw_name, "Firmware image name"); @@ -376,6 +378,14 @@ static inline void put_be32(__be32 val, __be32 __iomem * p) static struct net_device_stats *myri10ge_get_stats(struct net_device *dev); +static void set_fw_name(struct myri10ge_priv *mgp, char *name, bool allocated) +{ + if (mgp->fw_name_allocated) + kfree(mgp->fw_name); + mgp->fw_name = name; + mgp->fw_name_allocated = allocated; +} + static int myri10ge_send_cmd(struct myri10ge_priv *mgp, u32 cmd, struct myri10ge_cmd *data, int atomic) @@ -747,7 +757,7 @@ static int myri10ge_load_firmware(struct myri10ge_priv *mgp, int adopt) dev_warn(&mgp->pdev->dev, "via hotplug\n"); } - mgp->fw_name = "adopted"; + set_fw_name(mgp, "adopted", false); mgp->tx_boundary = 2048; myri10ge_dummy_rdma(mgp, 1); status = myri10ge_get_firmware_capabilities(mgp); @@ -3233,7 +3243,7 @@ static void myri10ge_firmware_probe(struct myri10ge_priv *mgp) * load the optimized firmware (which assumes aligned PCIe * completions) in order to see if it works on this host. */ - mgp->fw_name = myri10ge_fw_aligned; + set_fw_name(mgp, myri10ge_fw_aligned, false); status = myri10ge_load_firmware(mgp, 1); if (status != 0) { goto abort; @@ -3261,7 +3271,7 @@ static void myri10ge_firmware_probe(struct myri10ge_priv *mgp) abort: /* fall back to using the unaligned firmware */ mgp->tx_boundary = 2048; - mgp->fw_name = myri10ge_fw_unaligned; + set_fw_name(mgp, myri10ge_fw_unaligned, false); } @@ -3284,7 +3294,7 @@ static void myri10ge_select_firmware(struct myri10ge_priv *mgp) dev_info(&mgp->pdev->dev, "PCIE x%d Link\n", link_width); mgp->tx_boundary = 4096; - mgp->fw_name = myri10ge_fw_aligned; + set_fw_name(mgp, myri10ge_fw_aligned, false); } else { myri10ge_firmware_probe(mgp); } @@ -3293,22 +3303,29 @@ static void myri10ge_select_firmware(struct myri10ge_priv *mgp) dev_info(&mgp->pdev->dev, "Assuming aligned completions (forced)\n"); mgp->tx_boundary = 4096; - mgp->fw_name = myri10ge_fw_aligned; + set_fw_name(mgp, myri10ge_fw_aligned, false); } else { dev_info(&mgp->pdev->dev, "Assuming unaligned completions (forced)\n"); mgp->tx_boundary = 2048; - mgp->fw_name = myri10ge_fw_unaligned; + set_fw_name(mgp, myri10ge_fw_unaligned, false); } } + + kparam_block_sysfs_write(myri10ge_fw_name); if (myri10ge_fw_name != NULL) { - overridden = 1; - mgp->fw_name = myri10ge_fw_name; + char *fw_name = kstrdup(myri10ge_fw_name, GFP_KERNEL); + if (fw_name) { + overridden = 1; + set_fw_name(mgp, fw_name, true); + } } + kparam_unblock_sysfs_write(myri10ge_fw_name); + if (mgp->board_number < MYRI10GE_MAX_BOARDS && myri10ge_fw_names[mgp->board_number] != NULL && strlen(myri10ge_fw_names[mgp->board_number])) { - mgp->fw_name = myri10ge_fw_names[mgp->board_number]; + set_fw_name(mgp, myri10ge_fw_names[mgp->board_number], false); overridden = 1; } if (overridden) @@ -3660,6 +3677,7 @@ static void myri10ge_probe_slices(struct myri10ge_priv *mgp) struct myri10ge_cmd cmd; struct pci_dev *pdev = mgp->pdev; char *old_fw; + bool old_allocated; int i, status, ncpus, msix_cap; mgp->num_slices = 1; @@ -3672,17 +3690,23 @@ static void myri10ge_probe_slices(struct myri10ge_priv *mgp) /* try to load the slice aware rss firmware */ old_fw = mgp->fw_name; + old_allocated = mgp->fw_name_allocated; + /* don't free old_fw if we override it. */ + mgp->fw_name_allocated = false; + if (myri10ge_fw_name != NULL) { dev_info(&mgp->pdev->dev, "overriding rss firmware to %s\n", myri10ge_fw_name); - mgp->fw_name = myri10ge_fw_name; + set_fw_name(mgp, myri10ge_fw_name, false); } else if (old_fw == myri10ge_fw_aligned) - mgp->fw_name = myri10ge_fw_rss_aligned; + set_fw_name(mgp, myri10ge_fw_rss_aligned, false); else - mgp->fw_name = myri10ge_fw_rss_unaligned; + set_fw_name(mgp, myri10ge_fw_rss_unaligned, false); status = myri10ge_load_firmware(mgp, 0); if (status != 0) { dev_info(&pdev->dev, "Rss firmware not found\n"); + if (old_allocated) + kfree(old_fw); return; } @@ -3747,6 +3771,8 @@ static void myri10ge_probe_slices(struct myri10ge_priv *mgp) mgp->num_slices); if (status == 0) { pci_disable_msix(pdev); + if (old_allocated) + kfree(old_fw); return; } if (status > 0) @@ -3763,7 +3789,7 @@ static void myri10ge_probe_slices(struct myri10ge_priv *mgp) abort_with_fw: mgp->num_slices = 1; - mgp->fw_name = old_fw; + set_fw_name(mgp, old_fw, old_allocated); myri10ge_load_firmware(mgp, 0); } @@ -3993,6 +4019,7 @@ static int myri10ge_probe(struct pci_dev *pdev, const struct pci_device_id *ent) pci_disable_device(pdev); abort_with_netdev: + set_fw_name(mgp, NULL, false); free_netdev(netdev); return status; } @@ -4037,6 +4064,7 @@ static void myri10ge_remove(struct pci_dev *pdev) dma_free_coherent(&pdev->dev, sizeof(*mgp->cmd), mgp->cmd, mgp->cmd_bus); + set_fw_name(mgp, NULL, false); free_netdev(netdev); pci_disable_device(pdev); pci_set_drvdata(pdev, NULL);