Message-ID: <1352020617.10072.0.camel@jlt4.sipsolutions.net> (sfid-20121104_101715_760097_2BB21180)
Subject: Re: [PATCH] wireless: iwlwifi - add dma_mapping_error() checks to
 avoid warnings
From: Johannes Berg <johannes@sipsolutions.net>
To: shuah.khan@hp.com
Cc: johannes.berg@intel.com, wey-yi.w.guy@intel.com,
	linville@tuxdriver.com, ilw@linux.intel.com,
	emmanuel.grumbach@intel.com, donald.h.fry@intel.com,
	linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
	LKML <linux-kernel@vger.kernel.org>, shuahkhan@gmail.com
Date: Sun, 04 Nov 2012 10:16:57 +0100
In-Reply-To: <1351993233.4369.2.camel@lorien2> (sfid-20121104_024119_271188_5372C13E)
References: <1351993233.4369.2.camel@lorien2>
	 (sfid-20121104_024119_271188_5372C13E)
Content-Type: text/plain; charset="UTF-8"
Mime-Version: 1.0
Sender: linux-wireless-owner@vger.kernel.org

On Sat, 2012-11-03 at 19:40 -0600, Shuah Khan wrote:
> Add missing dma_mapping_error() checks to validate dma addresses returned by
> dma_map_page() calls to avoid the following warning:
> 
> [   28.475686] WARNING: at lib/dma-debug.c:933 check_unmap+0x459/0x8a0()
> [   28.475688] Hardware name: HP EliteBook 6930p
> [   28.475690] iwlwifi 0000:03:00.0: DMA-API: device driver failed to check map error[device address=0x00000000ffffa000] [size=8192 bytes] [mapped as page]
> [   28.475691] Modules linked in: arc4 bnep rfcomm iwldvm mac80211 snd_hda_codec_analog radeon snd_hda_intel snd_hda_codec coretemp kvm_intel snd_hwdep snd_pcm iwlwifi kvm btusb bluetooth snd_seq_midi snd_rawmidi ttm cfg80211 snd_seq_midi_event drm_kms_helper pata_pcmcia drm snd_seq binfmt_misc pcmcia snd_timer snd_seq_device tpm_infineon snd dm_multipath yenta_socket joydev pcmcia_rsrc pcmcia_core hp_wmi psmouse hp_accel microcode soundcore i2c_algo_bit sparse_keymap wmi ppdev lpc_ich lis3lv02d snd_page_alloc video tpm_tis serio_raw parport_pc input_polldev mac_hid lp parport firewire_ohci firewire_core crc_itu_t sdhci_pci sdhci e1000e

Thanks for the report. Since I think doing BUG_ON() in such a scenario
is a really bad idea, I've applied a different patch with your
Reported-by.

johannes