From: Johannes Berg <johannes.berg@xxxxxxxxx> commit 94543a8d4fb302817014981489f15cb3b92ec3c2 upstream. iwl_dbgfs_fh_reg_read() can cause crashes and/or BUG_ON in slub because the ifdefs are wrong, the code in iwl_dump_fh() should use DEBUGFS, not DEBUG to protect the buffer writing code. Also, while at it, clean up the arguments to the function, some code and make it generally safer. Reported-by: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Signed-off-by: John W. Linville <linville@xxxxxxxxxxxxx> [bwh: Backported to 3.2: adjust filenames and context] Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx> [wujg: Backported to 3.4: adjust context] Signed-off-by: Jianguo Wu <wujianguo@xxxxxxxxxx> --- drivers/net/wireless/iwlwifi/iwl-trans-pcie-int.h | 2 +- drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c | 2 +- drivers/net/wireless/iwlwifi/iwl-trans-pcie.c | 27 +++++++++++---------- 3 files changed, 16 insertions(+), 15 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-int.h b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-int.h index 3b844b7..dfa0d80 100644 --- a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-int.h +++ b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-int.h @@ -352,7 +352,7 @@ int iwl_queue_space(const struct iwl_queue *q); ******************************************************/ int iwl_dump_nic_event_log(struct iwl_trans *trans, bool full_log, char **buf, bool display); -int iwl_dump_fh(struct iwl_trans *trans, char **buf, bool display); +int iwl_dump_fh(struct iwl_trans *trans, char **buf); void iwl_dump_csr(struct iwl_trans *trans); /***************************************************** diff --git a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c index aa7aea1..bc3dd34 100644 --- a/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c +++ b/drivers/net/wireless/iwlwifi/iwl-trans-pcie-rx.c @@ -695,7 +695,7 @@ static void iwl_irq_handle_error(struct iwl_trans *trans) iwl_dump_nic_error_log(trans); iwl_dump_csr(trans); - iwl_dump_fh(trans, NULL, false); + iwl_dump_fh(trans, NULL); iwl_dump_nic_event_log(trans, false, NULL, false); iwl_op_mode_nic_error(trans->op_mode); diff --git a/drivers/net/wireless/iwlwifi/iwl-trans-pcie.c b/drivers/net/wireless/iwlwifi/iwl-trans-pcie.c index 8741048..1780d3f 100644 --- a/drivers/net/wireless/iwlwifi/iwl-trans-pcie.c +++ b/drivers/net/wireless/iwlwifi/iwl-trans-pcie.c @@ -1768,13 +1768,9 @@ static const char *get_fh_string(int cmd) } } -int iwl_dump_fh(struct iwl_trans *trans, char **buf, bool display) +int iwl_dump_fh(struct iwl_trans *trans, char **buf) { int i; -#ifdef CONFIG_IWLWIFI_DEBUG - int pos = 0; - size_t bufsz = 0; -#endif static const u32 fh_tbl[] = { FH_RSCSR_CHNL0_STTS_WPTR_REG, FH_RSCSR_CHNL0_RBDCB_BASE_REG, @@ -1786,29 +1782,34 @@ int iwl_dump_fh(struct iwl_trans *trans, char **buf, bool display) FH_TSSR_TX_STATUS_REG, FH_TSSR_TX_ERROR_REG }; -#ifdef CONFIG_IWLWIFI_DEBUG - if (display) { + +#ifdef CONFIG_IWLWIFI_DEBUGFS + if (buf) { + int pos = 0; + size_t bufsz = ARRAY_SIZE(fh_tbl) * 48 + 40; + bufsz = ARRAY_SIZE(fh_tbl) * 48 + 40; *buf = kmalloc(bufsz, GFP_KERNEL); if (!*buf) return -ENOMEM; pos += scnprintf(*buf + pos, bufsz - pos, "FH register values:\n"); - for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) { + + for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) pos += scnprintf(*buf + pos, bufsz - pos, " %34s: 0X%08x\n", get_fh_string(fh_tbl[i]), iwl_read_direct32(trans, fh_tbl[i])); - } + return pos; } #endif IWL_ERR(trans, "FH register values:\n"); - for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) { + for (i = 0; i < ARRAY_SIZE(fh_tbl); i++) IWL_ERR(trans, " %34s: 0X%08x\n", get_fh_string(fh_tbl[i]), iwl_read_direct32(trans, fh_tbl[i])); - } + return 0; } @@ -2152,11 +2153,11 @@ static ssize_t iwl_dbgfs_fh_reg_read(struct file *file, size_t count, loff_t *ppos) { struct iwl_trans *trans = file->private_data; - char *buf; + char *buf = NULL; int pos = 0; ssize_t ret = -EFAULT; - ret = pos = iwl_dump_fh(trans, &buf, true); + ret = pos = iwl_dump_fh(trans, &buf); if (buf) { ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos); -- 1.7.7 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html