2021-04-07 14:50:35

by Heiner Kallweit

[permalink] [raw]
Subject: iwl_pcie_gen2_enqueue_hcmd needs same fix as iwl_pcie_enqueue_hcmd

Same fix as in 2800aadc18a6 ("iwlwifi: Fix softirq/hardirq disabling in
iwl_pcie_enqueue_hcmd()") is needed for iwl_pcie_gen2_enqueue_hcmd.
I get the same lockdep warning on AX210.


2021-04-07 20:28:41

by Jiri Kosina

[permalink] [raw]
Subject: [PATCH] iwlwifi: Fix softirq/hardirq disabling in iwl_pcie_gen2_enqueue_hcmd()

On Wed, 7 Apr 2021, Heiner Kallweit wrote:

> Same fix as in 2800aadc18a6 ("iwlwifi: Fix softirq/hardirq disabling in
> iwl_pcie_enqueue_hcmd()") is needed for iwl_pcie_gen2_enqueue_hcmd.
> I get the same lockdep warning on AX210.

Makes sense, it's being called from exactly the same contexts.



From: Jiri Kosina <[email protected]>
Subject: [PATCH] iwlwifi: Fix softirq/hardirq disabling in iwl_pcie_gen2_enqueue_hcmd()

Analogically to what we did in 2800aadc18a6 ("iwlwifi: Fix
softirq/hardirq disabling in iwl_pcie_enqueue_hcmd()"), we must apply the
same fix to iwl_pcie_gen2_enqueue_hcmd(), as it's being called from
exactly the same contexts.

Reported-by: Heiner Kallweit <[email protected]
Signed-off-by: Jiri Kosina <[email protected]>
---

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c
index 4456abb9a074..34bde8c87324 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx-gen2.c
@@ -40,6 +40,7 @@ int iwl_pcie_gen2_enqueue_hcmd(struct iwl_trans *trans,
const u8 *cmddata[IWL_MAX_CMD_TBS_PER_TFD];
u16 cmdlen[IWL_MAX_CMD_TBS_PER_TFD];
struct iwl_tfh_tfd *tfd;
+ unsigned long flags;

copy_size = sizeof(struct iwl_cmd_header_wide);
cmd_size = sizeof(struct iwl_cmd_header_wide);
@@ -108,14 +109,14 @@ int iwl_pcie_gen2_enqueue_hcmd(struct iwl_trans *trans,
goto free_dup_buf;
}

- spin_lock_bh(&txq->lock);
+ spin_lock_irqsave(&txq->lock, flags);

idx = iwl_txq_get_cmd_index(txq, txq->write_ptr);
tfd = iwl_txq_get_tfd(trans, txq, txq->write_ptr);
memset(tfd, 0, sizeof(*tfd));

if (iwl_txq_space(trans, txq) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {
- spin_unlock_bh(&txq->lock);
+ spin_unlock_irqrestore(&txq->lock, flags);

IWL_ERR(trans, "No space in command queue\n");
iwl_op_mode_cmd_queue_full(trans->op_mode);
@@ -250,7 +251,7 @@ int iwl_pcie_gen2_enqueue_hcmd(struct iwl_trans *trans,
spin_unlock(&trans_pcie->reg_lock);

out:
- spin_unlock_bh(&txq->lock);
+ spin_unlock_irqrestore(&txq->lock, flags);
free_dup_buf:
if (idx < 0)
kfree(dup_buf);

--
Jiri Kosina
SUSE Labs

2021-04-07 20:34:12

by Johannes Berg

[permalink] [raw]
Subject: Re: [PATCH] iwlwifi: Fix softirq/hardirq disabling in iwl_pcie_gen2_enqueue_hcmd()

On Wed, 2021-04-07 at 09:51 +0200, Jiri Kosina wrote:
> On Wed, 7 Apr 2021, Heiner Kallweit wrote:
>
> > Same fix as in 2800aadc18a6 ("iwlwifi: Fix softirq/hardirq disabling in
> > iwl_pcie_enqueue_hcmd()") is needed for iwl_pcie_gen2_enqueue_hcmd.
> > I get the same lockdep warning on AX210.
>
> Makes sense, it's being called from exactly the same contexts.

I'm guessing nobody saw this before because the LEDs stuff is not
supported/used on newer devices :)

Still makes sense though.

Btw, I had a fix for your patch for some devices, see below. Already in
our tree, so Luca will send it on the way, just FYI/review here.

Thanks,
johannes


From: Johannes Berg <[email protected]>
Date: Tue, 6 Apr 2021 16:50:23 +0200
Subject: [PATCH] [BUGFIX] iwlwifi: pcie: don't enable BHs with IRQs disabled

After the fix from Jiri that disabled local IRQs instead of
just BHs (necessary to fix an issue with submitting a command
with IRQs already disabled), there was still a situation in
which we could deep in there enable BHs, if the device config
sets the apmg_wake_up_wa configuration, which is true on all
7000 series devices.

To fix that, but not require reverting commit 1ed08f6fb5ae
("iwlwifi: remove flags argument for nic_access"), split up
nic access into a version with BH manipulation to use most
of the time, and without it for this specific case where the
local IRQs are already disabled.

Signed-off-by: Johannes Berg <[email protected]>
---
.../wireless/intel/iwlwifi/pcie/internal.h | 5 ++++
.../net/wireless/intel/iwlwifi/pcie/trans.c | 24 ++++++++++++++++---
drivers/net/wireless/intel/iwlwifi/pcie/tx.c | 4 ++--
3 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
index 2c2389feb5e1..0b99f0c34111 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/internal.h
@@ -453,6 +453,11 @@ struct iwl_trans
const struct iwl_cfg_trans_params *cfg_trans);
void iwl_trans_pcie_free(struct iwl_trans *trans);

+bool __iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans);
+#define _iwl_trans_pcie_grab_nic_access(trans) \
+ __cond_lock(nic_access_nobh, \
+ likely(__iwl_trans_pcie_grab_nic_access(trans)))
+
/*****************************************************
* RX
******************************************************/
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
index f2869fc343e3..bf36fa72f22e 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/trans.c
@@ -2047,12 +2047,16 @@ static void iwl_trans_pcie_removal_wk(struct work_struct *wk)
module_put(THIS_MODULE);
}

-static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans)
+/*
+ * This version doesn't disable BHs but rather assumes they're
+ * already disabled.
+ */
+bool __iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans)
{
int ret;
struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);

- spin_lock_bh(&trans_pcie->reg_lock);
+ spin_lock(&trans_pcie->reg_lock);

if (trans_pcie->cmd_hold_nic_awake)
goto out;
@@ -2137,7 +2141,7 @@ static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans)
}

err:
- spin_unlock_bh(&trans_pcie->reg_lock);
+ spin_unlock(&trans_pcie->reg_lock);
return false;
}

@@ -2150,6 +2154,20 @@ out:
return true;
}

+static bool iwl_trans_pcie_grab_nic_access(struct iwl_trans *trans)
+{
+ bool ret;
+
+ local_bh_disable();
+ ret = __iwl_trans_pcie_grab_nic_access(trans);
+ if (ret) {
+ /* keep BHs disabled until iwl_trans_pcie_release_nic_access */
+ return ret;
+ }
+ local_bh_enable();
+ return false;
+}
+
static void iwl_trans_pcie_release_nic_access(struct iwl_trans *trans)
{
struct iwl_trans_pcie *trans_pcie = IWL_TRANS_GET_PCIE_TRANS(trans);
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
index 0346505351f5..4f6c187eed69 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/tx.c
@@ -643,7 +643,7 @@ static int iwl_pcie_set_cmd_in_flight(struct iwl_trans *trans,
* returned. This needs to be done only on NICs that have
* apmg_wake_up_wa set (see above.)
*/
- if (!iwl_trans_grab_nic_access(trans))
+ if (!_iwl_trans_pcie_grab_nic_access(trans))
return -EIO;

/*
@@ -652,7 +652,7 @@ static int iwl_pcie_set_cmd_in_flight(struct iwl_trans *trans,
* already true, so it's OK to unconditionally set it to true.
*/
trans_pcie->cmd_hold_nic_awake = true;
- spin_unlock_bh(&trans_pcie->reg_lock);
+ spin_unlock(&trans_pcie->reg_lock);

return 0;
}
--
2.30.2



2021-04-07 20:34:12

by Johannes Berg

[permalink] [raw]
Subject: Re: [PATCH] iwlwifi: Fix softirq/hardirq disabling in iwl_pcie_gen2_enqueue_hcmd()

On Wed, 2021-04-07 at 09:55 +0200, Johannes Berg wrote:
> On Wed, 2021-04-07 at 09:51 +0200, Jiri Kosina wrote:
> > On Wed, 7 Apr 2021, Heiner Kallweit wrote:
> >
> > > Same fix as in 2800aadc18a6 ("iwlwifi: Fix softirq/hardirq disabling in
> > > iwl_pcie_enqueue_hcmd()") is needed for iwl_pcie_gen2_enqueue_hcmd.
> > > I get the same lockdep warning on AX210.
> >
> > Makes sense, it's being called from exactly the same contexts.
>
> I'm guessing nobody saw this before because the LEDs stuff is not
> supported/used on newer devices :)

Eh, wait, Heiner said he sees the same warning? With LEDs? I was pretty
sure that's not supported by the later firmware, but maybe some other
path? Anyway this fix seems right.

johannes

2021-04-07 20:36:35

by Heiner Kallweit

[permalink] [raw]
Subject: Re: [PATCH] iwlwifi: Fix softirq/hardirq disabling in iwl_pcie_gen2_enqueue_hcmd()

On 07.04.2021 09:56, Johannes Berg wrote:
> On Wed, 2021-04-07 at 09:55 +0200, Johannes Berg wrote:
>> On Wed, 2021-04-07 at 09:51 +0200, Jiri Kosina wrote:
>>> On Wed, 7 Apr 2021, Heiner Kallweit wrote:
>>>
>>>> Same fix as in 2800aadc18a6 ("iwlwifi: Fix softirq/hardirq disabling in
>>>> iwl_pcie_enqueue_hcmd()") is needed for iwl_pcie_gen2_enqueue_hcmd.
>>>> I get the same lockdep warning on AX210.
>>>
>>> Makes sense, it's being called from exactly the same contexts.
>>
>> I'm guessing nobody saw this before because the LEDs stuff is not
>> supported/used on newer devices :)
>
> Eh, wait, Heiner said he sees the same warning? With LEDs? I was pretty
> sure that's not supported by the later firmware, but maybe some other
> path? Anyway this fix seems right.
>
> johannes
>

For your reference here the warning I got.

[ 27.645349] ------------[ cut here ]------------
[ 27.645453] WARNING: CPU: 1 PID: 2323 at kernel/softirq.c:364 __local_bh_enable_ip+0x85/0xc0
[ 27.645516] Modules linked in: snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio cmac bnep iwlmvm led_class vfat fat mac80211 libarc4 iwlwifi x86_pkg_temp_thermal coretemp i915 btusb btintel bluetooth snd_hda_intel snd_intel_dspcfg aesni_intel r8169 cfg80211 realtek ecdh_generic snd_hda_codec mdio_devres crypto_simd i2c_i801 rfkill intel_gtt ecc mei_me cryptd i2c_smbus snd_hda_core libphy mei i2c_algo_bit snd_pcm drm_kms_helper syscopyarea sysfillrect sysimgblt snd_timer fb_sys_fops snd sch_fq_codel crypto_user drm efivarfs ext4 mbcache jbd2 ums_realtek crc32c_intel ahci libahci libata
[ 27.645991] CPU: 1 PID: 2323 Comm: ip Not tainted 5.12.0-rc6-next-20210406+ #4
[ 27.646040] Hardware name: NA ZBOX-CI327NANO-GS-01/ZBOX-CI327NANO-GS-01, BIOS 5.12 04/28/2020
[ 27.646094] RIP: 0010:__local_bh_enable_ip+0x85/0xc0
[ 27.646132] Code: 8b 05 af c6 ba 47 a9 00 ff ff 00 74 32 65 ff 0d a1 c6 ba 47 e8 7c b4 0e 00 fb 5b 41 5c 5d c3 65 8b 05 6b cc ba 47 85 c0 75 ae <0f> 0b eb aa e8 92 b3 0e 00 eb ab 4c 89 e7 e8 18 ff 05 00 eb b4 65
[ 27.646275] RSP: 0018:ffffbb574062b1b8 EFLAGS: 00010046
[ 27.646311] RAX: 0000000000000000 RBX: 0000000000000201 RCX: 0000000000000000
[ 27.646355] RDX: 0000000000000003 RSI: 0000000000000201 RDI: ffffffffc051192b
[ 27.646401] RBP: ffffbb574062b1c8 R08: 0000000000000000 R09: 0000000000000001
[ 27.646444] R10: ffff9eec03243e00 R11: 0000000000000000 R12: ffffffffc051192b
[ 27.646488] R13: ffff9eec07e72b40 R14: 0000000000000001 R15: 0000000000000000
[ 27.646533] FS: 00007fce73f11740(0000) GS:ffff9eec7bc80000(0000) knlGS:0000000000000000
[ 27.646584] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 27.646622] CR2: 00005581ebf10cc0 CR3: 0000000102924000 CR4: 00000000003506e0
[ 27.646668] Call Trace:
[ 27.646687] _raw_spin_unlock_bh+0x2c/0x40
[ 27.646718] iwl_pcie_gen2_enqueue_hcmd+0x50b/0x890 [iwlwifi]
[ 27.646781] iwl_trans_txq_send_hcmd+0x68/0x3b0 [iwlwifi]
[ 27.646836] iwl_trans_send_cmd+0x7d/0x170 [iwlwifi]
[ 27.646888] iwl_mvm_send_cmd+0x29/0x80 [iwlmvm]
[ 27.646942] iwl_mvm_led_set+0xa5/0xd0 [iwlmvm]
[ 27.646995] iwl_led_brightness_set+0x1a/0x20 [iwlmvm]
[ 27.647050] led_set_brightness_nosleep+0x24/0x50
[ 27.647085] led_set_brightness+0x41/0x50
[ 27.647115] led_trigger_event+0x46/0x70
[ 27.647143] ieee80211_led_radio+0x24/0x30 [mac80211]
[ 27.647288] ieee80211_do_open+0x4c4/0x9a0 [mac80211]
[ 27.647379] ieee80211_open+0x69/0x90 [mac80211]
[ 27.647487] __dev_open+0xd6/0x190
[ 27.647517] __dev_change_flags+0x1b2/0x230
[ 27.647548] dev_change_flags+0x21/0x60
[ 27.647577] do_setlink+0x289/0x1190
[ 27.647607] ? __nla_validate_parse+0x60/0xbd0
[ 27.647644] __rtnl_newlink+0x61c/0xa10
[ 27.647677] ? mark_lock+0x25/0x1110
[ 27.647709] ? rcu_read_lock_sched_held+0x41/0x80
[ 27.647744] ? kmem_cache_alloc_trace+0x21e/0x250
[ 27.647781] rtnl_newlink+0x44/0x70
[ 27.647808] rtnetlink_rcv_msg+0x17f/0x4b0
[ 27.647838] ? netlink_deliver_tap+0x10e/0x3f0
[ 27.647873] ? find_held_lock+0x31/0x90
[ 27.647902] ? netlink_deliver_tap+0x10e/0x3f0
[ 27.647934] ? rtnetlink_put_metrics+0x1d0/0x1d0
[ 27.647967] netlink_rcv_skb+0x50/0xf0
[ 27.648000] rtnetlink_rcv+0x10/0x20
[ 27.648027] netlink_unicast+0x1a3/0x270
[ 27.648056] netlink_sendmsg+0x22c/0x430
[ 27.648085] ? netlink_unicast+0x270/0x270
[ 27.648116] ____sys_sendmsg+0x2a6/0x2e0
[ 27.648147] ? import_iovec+0x1b/0x20
[ 27.648179] ? sendmsg_copy_msghdr+0x79/0xa0
[ 27.648211] ___sys_sendmsg+0x82/0xc0
[ 27.648240] __sys_sendmsg+0x62/0xb0
[ 27.648268] ? syscall_enter_from_user_mode+0x21/0x60
[ 27.648307] __x64_sys_sendmsg+0x1a/0x20
[ 27.648337] do_syscall_64+0x38/0x50
[ 27.648366] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 27.648403] RIP: 0033:0x7fce74030737
[ 27.648433] Code: 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
[ 27.648547] RSP: 002b:00007ffdd61d1498 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 27.648600] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fce74030737
[ 27.648645] RDX: 0000000000000000 RSI: 00007ffdd61d1500 RDI: 0000000000000003
[ 27.648691] RBP: 00000000606d6d4f R08: 0000000000000001 R09: 00007fce740f1a60
[ 27.648736] R10: 0000000000000230 R11: 0000000000000246 R12: 0000000000000001
[ 27.648782] R13: 00007ffdd61d15d0 R14: 0000000000000000 R15: 00005581ebec6020
[ 27.648830] irq event stamp: 94495
[ 27.648855] hardirqs last enabled at (94493): [<ffffffffb846a864>] __local_bh_enable_ip+0x74/0xc0
[ 27.648917] hardirqs last disabled at (94494): [<ffffffffb8bf198f>] _raw_read_lock_irqsave+0x7f/0x90
[ 27.648977] softirqs last enabled at (94492): [<ffffffffc051192b>] iwl_pcie_gen2_enqueue_hcmd+0x50b/0x890 [iwlwifi]
[ 27.649064] softirqs last disabled at (94495): [<ffffffffc0511516>] iwl_pcie_gen2_enqueue_hcmd+0xf6/0x890 [iwlwifi]
[ 27.649151] ---[ end trace da6e11a6f99dba37 ]---
[ 27.649242] ------------[ cut here ]------------
[ 27.649326] raw_local_irq_restore() called with IRQs enabled
[ 27.649367] WARNING: CPU: 1 PID: 2323 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x22/0x30
[ 27.649433] Modules linked in: snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio cmac bnep iwlmvm led_class vfat fat mac80211 libarc4 iwlwifi x86_pkg_temp_thermal coretemp i915 btusb btintel bluetooth snd_hda_intel snd_intel_dspcfg aesni_intel r8169 cfg80211 realtek ecdh_generic snd_hda_codec mdio_devres crypto_simd i2c_i801 rfkill intel_gtt ecc mei_me cryptd i2c_smbus snd_hda_core libphy mei i2c_algo_bit snd_pcm drm_kms_helper syscopyarea sysfillrect sysimgblt snd_timer fb_sys_fops snd sch_fq_codel crypto_user drm efivarfs ext4 mbcache jbd2 ums_realtek crc32c_intel ahci libahci libata
[ 27.649900] CPU: 1 PID: 2323 Comm: ip Tainted: G W 5.12.0-rc6-next-20210406+ #4
[ 27.649956] Hardware name: NA ZBOX-CI327NANO-GS-01/ZBOX-CI327NANO-GS-01, BIOS 5.12 04/28/2020
[ 27.650010] RIP: 0010:warn_bogus_irq_restore+0x22/0x30
[ 27.650047] Code: cc cc cc cc cc cc cc cc 55 48 89 e5 80 3d ca 51 9f 00 00 74 02 5d c3 48 c7 c7 18 07 21 b9 c6 05 b8 51 9f 00 01 e8 12 f8 fc ff <0f> 0b 5d c3 cc cc cc cc cc cc cc cc cc cc 55 48 89 e5 41 54 53 44
[ 27.650177] RSP: 0018:ffffbb574062b3d0 EFLAGS: 00010286
[ 27.650216] RAX: 0000000000000000 RBX: 0000000000000200 RCX: ffff9eec7bc976f8
[ 27.650303] RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffff9eec7bc976f0
[ 27.650423] RBP: ffffbb574062b3d0 R08: 0000000000000001 R09: 0000000000000001
[ 27.650542] R10: 00000000ffffe000 R11: 3fffffffffffffff R12: ffff9eec08e9ac78
[ 27.650661] R13: 00000000000000ff R14: 0000000000000286 R15: ffff9eec08e9ac78
[ 27.650781] FS: 00007fce73f11740(0000) GS:ffff9eec7bc80000(0000) knlGS:0000000000000000
[ 27.650919] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 27.651070] CR2: 00005581ebf10cc0 CR3: 0000000102924000 CR4: 00000000003506e0
[ 27.651243] Call Trace:
[ 27.651298] _raw_read_unlock_irqrestore+0x4f/0x60
[ 27.651392] led_trigger_event+0x64/0x70
[ 27.651470] ieee80211_led_radio+0x24/0x30 [mac80211]
[ 27.651758] ieee80211_do_open+0x4c4/0x9a0 [mac80211]
[ 27.652006] ieee80211_open+0x69/0x90 [mac80211]
[ 27.652334] __dev_open+0xd6/0x190
[ 27.652407] __dev_change_flags+0x1b2/0x230
[ 27.652490] dev_change_flags+0x21/0x60
[ 27.652566] do_setlink+0x289/0x1190
[ 27.652641] ? __nla_validate_parse+0x60/0xbd0
[ 27.652729] __rtnl_newlink+0x61c/0xa10
[ 27.652809] ? mark_lock+0x25/0x1110
[ 27.652886] ? rcu_read_lock_sched_held+0x41/0x80
[ 27.652977] ? kmem_cache_alloc_trace+0x21e/0x250
[ 27.653068] rtnl_newlink+0x44/0x70
[ 27.653139] rtnetlink_rcv_msg+0x17f/0x4b0
[ 27.653257] ? netlink_deliver_tap+0x10e/0x3f0
[ 27.653343] ? find_held_lock+0x31/0x90
[ 27.653419] ? netlink_deliver_tap+0x10e/0x3f0
[ 27.653504] ? rtnetlink_put_metrics+0x1d0/0x1d0
[ 27.653591] netlink_rcv_skb+0x50/0xf0
[ 27.653667] rtnetlink_rcv+0x10/0x20
[ 27.653738] netlink_unicast+0x1a3/0x270
[ 27.653816] netlink_sendmsg+0x22c/0x430
[ 27.653893] ? netlink_unicast+0x270/0x270
[ 27.653973] ____sys_sendmsg+0x2a6/0x2e0
[ 27.654052] ? import_iovec+0x1b/0x20
[ 27.654127] ? sendmsg_copy_msghdr+0x79/0xa0
[ 27.654250] ___sys_sendmsg+0x82/0xc0
[ 27.654332] __sys_sendmsg+0x62/0xb0
[ 27.654407] ? syscall_enter_from_user_mode+0x21/0x60
[ 27.654502] __x64_sys_sendmsg+0x1a/0x20
[ 27.654581] do_syscall_64+0x38/0x50
[ 27.654654] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 27.654748] RIP: 0033:0x7fce74030737
[ 27.654819] Code: 0c 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
[ 27.655111] RSP: 002b:00007ffdd61d1498 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[ 27.655284] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fce74030737
[ 27.655405] RDX: 0000000000000000 RSI: 00007ffdd61d1500 RDI: 0000000000000003
[ 27.655523] RBP: 00000000606d6d4f R08: 0000000000000001 R09: 00007fce740f1a60
[ 27.655641] R10: 0000000000000230 R11: 0000000000000246 R12: 0000000000000001
[ 27.655759] R13: 00007ffdd61d15d0 R14: 0000000000000000 R15: 00005581ebec6020
[ 27.655879] irq event stamp: 95385
[ 27.655944] hardirqs last enabled at (95393): [<ffffffffb84d2270>] console_unlock+0x4a0/0x5c0
[ 27.656093] hardirqs last disabled at (95400): [<ffffffffb84d21e3>] console_unlock+0x413/0x5c0
[ 27.656275] softirqs last enabled at (95022): [<ffffffffb846a9ec>] irq_exit_rcu+0xac/0xe0
[ 27.656420] softirqs last disabled at (95017): [<ffffffffb846a9ec>] irq_exit_rcu+0xac/0xe0
[ 27.656561] ---[ end trace da6e11a6f99dba38 ]---