lkml.org 
[lkml]   [2015]   [Apr]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    SubjectRe: [RFC][PATCH] firmware: Drop WARN from usermodehelper_read_trylock error case
    From
    On Wed, Apr 29, 2015 at 8:11 AM, Laura Abbott <labbott@fedoraproject.org> wrote:
    > We've received a number of reports of warnings when coming
    > out of suspend with certain bluetooth firmware configurations:
    >
    > WARNING: CPU: 3 PID: 3280 at drivers/base/firmware_class.c:1126
    > _request_firmware+0x558/0x810()
    > Modules linked in: ccm ip6t_rpfilter ip6t_REJECT nf_reject_ipv6
    > xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter
    > ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6
    > ip6table_mangle ip6table_security ip6table_raw ip6table_filter
    > ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4
    > nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw
    > binfmt_misc bnep intel_rapl iosf_mbi arc4 x86_pkg_temp_thermal
    > snd_hda_codec_hdmi coretemp kvm_intel joydev snd_hda_codec_realtek
    > iwldvm snd_hda_codec_generic kvm iTCO_wdt mac80211 iTCO_vendor_support
    > snd_hda_intel snd_hda_controller snd_hda_codec crct10dif_pclmul
    > snd_hwdep crc32_pclmul snd_seq crc32c_intel ghash_clmulni_intel uvcvideo
    > snd_seq_device iwlwifi btusb videobuf2_vmalloc snd_pcm videobuf2_core
    > serio_raw bluetooth cfg80211 videobuf2_memops sdhci_pci v4l2_common
    > videodev thinkpad_acpi sdhci i2c_i801 lpc_ich mfd_core wacom mmc_core
    > media snd_timer tpm_tis hid_logitech_hidpp wmi tpm rfkill snd mei_me mei
    > shpchp soundcore nfsd auth_rpcgss nfs_acl lockd grace sunrpc i915
    > i2c_algo_bit drm_kms_helper e1000e drm hid_logitech_dj ptp pps_core
    > video
    > CPU: 3 PID: 3280 Comm: kworker/u17:0 Not tainted 3.19.3-200.fc21.x86_64
    > Hardware name: LENOVO 343522U/343522U, BIOS GCET96WW (2.56 ) 10/22/2013
    > Workqueue: hci0 hci_power_on [bluetooth]
    > 0000000000000000 0000000089944328 ffff88040acffb78 ffffffff8176e215
    > 0000000000000000 0000000000000000 ffff88040acffbb8 ffffffff8109bc1a
    > 0000000000000000 ffff88040acffcd0 00000000fffffff5 ffff8804076bac40
    > Call Trace:
    > [<ffffffff8176e215>] dump_stack+0x45/0x57
    > [<ffffffff8109bc1a>] warn_slowpath_common+0x8a/0xc0
    > [<ffffffff8109bd4a>] warn_slowpath_null+0x1a/0x20
    > [<ffffffff814dbe78>] _request_firmware+0x558/0x810
    > [<ffffffff814dc165>] request_firmware+0x35/0x50
    > [<ffffffffa03a7886>] btusb_setup_bcm_patchram+0x86/0x590 [btusb]
    > [<ffffffff814d40e6>] ? rpm_idle+0xd6/0x230
    > [<ffffffffa04d4801>] hci_dev_do_open+0xe1/0xa90 [bluetooth]
    > [<ffffffff810c51dd>] ? ttwu_do_activate.constprop.90+0x5d/0x70
    > [<ffffffffa04d5980>] hci_power_on+0x40/0x200 [bluetooth]
    > [<ffffffff810b487c>] process_one_work+0x14c/0x3f0
    > [<ffffffff810b52f3>] worker_thread+0x53/0x470
    > [<ffffffff810b52a0>] ? rescuer_thread+0x300/0x300
    > [<ffffffff810ba548>] kthread+0xd8/0xf0
    > [<ffffffff810ba470>] ? kthread_create_on_node+0x1b0/0x1b0
    > [<ffffffff81774958>] ret_from_fork+0x58/0x90
    > [<ffffffff810ba470>] ? kthread_create_on_node+0x1b0/0x1b0
    >
    > This occurs after every resume.
    >
    > When resuming, the bluetooth driver needs to re-request the
    > firmware. This re-request is happening before usermodehelper
    > is fully enabled. If the firmware load succeeded previously, the
    > caching behavior of the firmware code typically negates the
    > need to call the usermodehelper code again and the request
    > succeeds. If the firmware was never loaded because it isn't
    > actually present in the file system, this results in a call
    > to usermodehelper and a failure warning every resume. Rather

    Yes, it is a driver problem, and loading firmware from filesystem
    isn't safe during resume, and that is the purpose of the warning.

    > than have a WARN clogging up the kernel messages each time,
    > just drop the warn. There is still a dev_err for debugging
    > purposes.
    >
    > Signed-off-by: Laura Abbott <labbott@fedoraproject.org>
    > ---
    > This might be papering over a real issue but I'm not
    > familiar enough with any of suspend/resume, bluetooth,
    > or firmware loading to identify an alternate fix.
    > The backtrace is from bcm patchram but the problem
    > isn't limited to that hardware. Intel also does a
    > request firmware and I was able to reproduce the
    > same backtrace on that driver by requesting non-existant
    > firmware file.
    > ---
    > drivers/base/firmware_class.c | 2 +-
    > 1 file changed, 1 insertion(+), 1 deletion(-)
    >
    > diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
    > index 171841a..48ce9ac 100644
    > --- a/drivers/base/firmware_class.c
    > +++ b/drivers/base/firmware_class.c
    > @@ -1115,7 +1115,7 @@ _request_firmware(const struct firmware **firmware_p, const char *name,
    > }
    > } else {
    > ret = usermodehelper_read_trylock();
    > - if (WARN_ON(ret)) {
    > + if (ret) {
    > dev_err(device, "firmware: %s will not be loaded\n",
    > name);
    > goto out;
    > --
    > 2.1.0
    >


    \
     
     \ /
      Last update: 2015-04-29 07:01    [W:6.894 / U:0.040 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site