From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: Taehee Yoo <ap420073@gmail.com>, Jakub Kicinski <kuba@kernel.org>,
Sasha Levin <sashal@kernel.org>,
netdev@vger.kernel.org
Subject: [PATCH AUTOSEL 5.5 522/542] netdevsim: disable devlink reload when resources are being used
Date: Fri, 14 Feb 2020 10:48:34 -0500 [thread overview]
Message-ID: <20200214154854.6746-522-sashal@kernel.org> (raw)
In-Reply-To: <20200214154854.6746-1-sashal@kernel.org>
From: Taehee Yoo <ap420073@gmail.com>
[ Upstream commit 6ab63366e1ec4ec1900f253aa64727b4b5f4ee73 ]
devlink reload destroys resources and allocates resources again.
So, when devices and ports resources are being used, devlink reload
function should not be executed. In order to avoid this race, a new
lock is added and new_port() and del_port() call devlink_reload_disable()
and devlink_reload_enable().
Thread0 Thread1
{new/del}_port() {new/del}_port()
devlink_reload_disable()
devlink_reload_disable()
devlink_reload_enable()
//here
devlink_reload_enable()
Before Thread1's devlink_reload_enable(), the devlink is already allowed
to execute reload because Thread0 allows it. devlink reload disable/enable
variable type is bool. So the above case would exist.
So, disable/enable should be executed atomically.
In order to do that, a new lock is used.
Test commands:
modprobe netdevsim
echo 1 > /sys/bus/netdevsim/new_device
while :
do
echo 1 > /sys/devices/netdevsim1/new_port &
echo 1 > /sys/devices/netdevsim1/del_port &
devlink dev reload netdevsim/netdevsim1 &
done
Splat looks like:
[ 23.342145][ T932] DEBUG_LOCKS_WARN_ON(mutex_is_locked(lock))
[ 23.342159][ T932] WARNING: CPU: 0 PID: 932 at kernel/locking/mutex-debug.c:103 mutex_destroy+0xc7/0xf0
[ 23.344182][ T932] Modules linked in: netdevsim openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nf_dx
[ 23.346485][ T932] CPU: 0 PID: 932 Comm: devlink Not tainted 5.5.0+ #322
[ 23.347696][ T932] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 23.348893][ T932] RIP: 0010:mutex_destroy+0xc7/0xf0
[ 23.349505][ T932] Code: e0 07 83 c0 03 38 d0 7c 04 84 d2 75 2e 8b 05 00 ac b0 02 85 c0 75 8b 48 c7 c6 00 5e 07 96 40
[ 23.351887][ T932] RSP: 0018:ffff88806208f810 EFLAGS: 00010286
[ 23.353963][ T932] RAX: dffffc0000000008 RBX: ffff888067f6f2c0 RCX: ffffffff942c4bd4
[ 23.355222][ T932] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff96dac5b4
[ 23.356169][ T932] RBP: ffff888067f6f000 R08: fffffbfff2d235a5 R09: fffffbfff2d235a5
[ 23.357160][ T932] R10: 0000000000000001 R11: fffffbfff2d235a4 R12: ffff888067f6f208
[ 23.358288][ T932] R13: ffff88806208fa70 R14: ffff888067f6f000 R15: ffff888069ce3800
[ 23.359307][ T932] FS: 00007fe2a3876740(0000) GS:ffff88806c000000(0000) knlGS:0000000000000000
[ 23.360473][ T932] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 23.361319][ T932] CR2: 00005561357aa000 CR3: 000000005227a006 CR4: 00000000000606f0
[ 23.362323][ T932] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 23.363417][ T932] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 23.364414][ T932] Call Trace:
[ 23.364828][ T932] nsim_dev_reload_destroy+0x77/0xb0 [netdevsim]
[ 23.365655][ T932] nsim_dev_reload_down+0x84/0xb0 [netdevsim]
[ 23.366433][ T932] devlink_reload+0xb1/0x350
[ 23.367010][ T932] genl_rcv_msg+0x580/0xe90
[ ...]
[ 23.531729][ T1305] kernel BUG at lib/list_debug.c:53!
[ 23.532523][ T1305] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[ 23.533467][ T1305] CPU: 2 PID: 1305 Comm: bash Tainted: G W 5.5.0+ #322
[ 23.534962][ T1305] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[ 23.536503][ T1305] RIP: 0010:__list_del_entry_valid+0xe6/0x150
[ 23.538346][ T1305] Code: 89 ea 48 c7 c7 00 73 1e 96 e8 df f7 4c ff 0f 0b 48 c7 c7 60 73 1e 96 e8 d1 f7 4c ff 0f 0b 44
[ 23.541068][ T1305] RSP: 0018:ffff888047c27b58 EFLAGS: 00010282
[ 23.542001][ T1305] RAX: 0000000000000054 RBX: ffff888067f6f318 RCX: 0000000000000000
[ 23.543051][ T1305] RDX: 0000000000000054 RSI: 0000000000000008 RDI: ffffed1008f84f61
[ 23.544072][ T1305] RBP: ffff88804aa0fca0 R08: ffffed100d940539 R09: ffffed100d940539
[ 23.545085][ T1305] R10: 0000000000000001 R11: ffffed100d940538 R12: ffff888047c27cb0
[ 23.546422][ T1305] R13: ffff88806208b840 R14: ffffffff981976c0 R15: ffff888067f6f2c0
[ 23.547406][ T1305] FS: 00007f76c0431740(0000) GS:ffff88806c800000(0000) knlGS:0000000000000000
[ 23.548527][ T1305] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 23.549389][ T1305] CR2: 00007f5048f1a2f8 CR3: 000000004b310006 CR4: 00000000000606e0
[ 23.550636][ T1305] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 23.551578][ T1305] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 23.552597][ T1305] Call Trace:
[ 23.553004][ T1305] mutex_remove_waiter+0x101/0x520
[ 23.553646][ T1305] __mutex_lock+0xac7/0x14b0
[ 23.554218][ T1305] ? nsim_dev_port_del+0x4e/0x140 [netdevsim]
[ 23.554908][ T1305] ? mutex_lock_io_nested+0x1380/0x1380
[ 23.555570][ T1305] ? _parse_integer+0xf0/0xf0
[ 23.556043][ T1305] ? kstrtouint+0x86/0x110
[ 23.556504][ T1305] ? nsim_dev_port_del+0x4e/0x140 [netdevsim]
[ 23.557133][ T1305] nsim_dev_port_del+0x4e/0x140 [netdevsim]
[ 23.558024][ T1305] del_port_store+0xcc/0xf0 [netdevsim]
[ ... ]
Fixes: 75ba029f3c07 ("netdevsim: implement proper devlink reload")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/netdevsim/bus.c | 19 +++++++++++++++++++
drivers/net/netdevsim/netdevsim.h | 2 ++
2 files changed, 21 insertions(+)
diff --git a/drivers/net/netdevsim/bus.c b/drivers/net/netdevsim/bus.c
index c086d1e522dc0..e455dd1cf4d0a 100644
--- a/drivers/net/netdevsim/bus.c
+++ b/drivers/net/netdevsim/bus.c
@@ -97,6 +97,8 @@ new_port_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+ struct nsim_dev *nsim_dev = dev_get_drvdata(dev);
+ struct devlink *devlink;
unsigned int port_index;
int ret;
@@ -106,7 +108,14 @@ new_port_store(struct device *dev, struct device_attribute *attr,
ret = kstrtouint(buf, 0, &port_index);
if (ret)
return ret;
+
+ devlink = priv_to_devlink(nsim_dev);
+
+ mutex_lock(&nsim_bus_dev->nsim_bus_reload_lock);
+ devlink_reload_disable(devlink);
ret = nsim_dev_port_add(nsim_bus_dev, port_index);
+ devlink_reload_enable(devlink);
+ mutex_unlock(&nsim_bus_dev->nsim_bus_reload_lock);
return ret ? ret : count;
}
@@ -117,6 +126,8 @@ del_port_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+ struct nsim_dev *nsim_dev = dev_get_drvdata(dev);
+ struct devlink *devlink;
unsigned int port_index;
int ret;
@@ -126,7 +137,14 @@ del_port_store(struct device *dev, struct device_attribute *attr,
ret = kstrtouint(buf, 0, &port_index);
if (ret)
return ret;
+
+ devlink = priv_to_devlink(nsim_dev);
+
+ mutex_lock(&nsim_bus_dev->nsim_bus_reload_lock);
+ devlink_reload_disable(devlink);
ret = nsim_dev_port_del(nsim_bus_dev, port_index);
+ devlink_reload_enable(devlink);
+ mutex_unlock(&nsim_bus_dev->nsim_bus_reload_lock);
return ret ? ret : count;
}
@@ -311,6 +329,7 @@ nsim_bus_dev_new(unsigned int id, unsigned int port_count)
nsim_bus_dev->dev.type = &nsim_bus_dev_type;
nsim_bus_dev->port_count = port_count;
nsim_bus_dev->initial_net = current->nsproxy->net_ns;
+ mutex_init(&nsim_bus_dev->nsim_bus_reload_lock);
/* Disallow using nsim_bus_dev */
smp_store_release(&nsim_bus_dev->init, false);
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index ea3931391ce21..be100b11a0550 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -240,6 +240,8 @@ struct nsim_bus_dev {
*/
unsigned int num_vfs;
struct nsim_vf_config *vfconfigs;
+ /* Lock for devlink->reload_enabled in netdevsim module */
+ struct mutex nsim_bus_reload_lock;
bool init;
};
--
2.20.1
next prev parent reply other threads:[~2020-02-14 16:01 UTC|newest]
Thread overview: 77+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20200214154854.6746-1-sashal@kernel.org>
2020-02-14 15:39 ` [PATCH AUTOSEL 5.5 004/542] ath10k: Fix qmi init error handling Sasha Levin
2020-02-14 15:39 ` [PATCH AUTOSEL 5.5 005/542] wil6210: fix break that is never reached because of zero'ing of a retry counter Sasha Levin
2020-02-14 15:40 ` [PATCH AUTOSEL 5.5 026/542] brcmfmac: Fix memory leak in brcmf_p2p_create_p2pdev() Sasha Levin
2020-02-14 15:40 ` [PATCH AUTOSEL 5.5 027/542] brcmfmac: Fix use after free in brcmf_sdio_readframes() Sasha Levin
2020-02-14 15:40 ` [PATCH AUTOSEL 5.5 034/542] gianfar: Fix TX timestamping with a stacked DSA driver Sasha Levin
2020-02-14 15:40 ` [PATCH AUTOSEL 5.5 057/542] arm64: dts: marvell: clearfog-gt-8k: fix switch cpu port node Sasha Levin
2020-02-14 15:40 ` [PATCH AUTOSEL 5.5 066/542] net: ethernet: ixp4xx: Standard module init Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 091/542] wan/hdlc_x25: fix skb handling Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 107/542] ath10k: Correct the DMA direction for management tx buffers Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 108/542] IB/mlx5: Return the administrative GUID if exists Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 109/542] rtw88: fix rate mask for 1SS chip Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 110/542] brcmfmac: sdio: Fix OOB interrupt initialization on brcm43362 Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 111/542] libertas: don't exit from lbs_ibss_join_existing() with RCU read lock held Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 112/542] libertas: make lbs_ibss_join_existing() return error code on rates overflow Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 125/542] netfilter: flowtable: Fix missing flush hardware on table free Sasha Levin
2020-02-14 15:41 ` [PATCH AUTOSEL 5.5 126/542] netfilter: flowtable: Fix hardware flush order on nf_flow_table_cleanup Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 132/542] mt76: mt7615: fix max_nss in mt7615_eeprom_parse_hw_cap Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 133/542] bpftool: Don't crash on missing xlated program instructions Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 134/542] bpf, sockhash: Synchronize_rcu before free'ing map Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 135/542] bpf, sockmap: Check update requirements after locking Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 136/542] bpf: Improve bucket_log calculation logic Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 137/542] bpf, sockmap: Don't sleep while holding RCU lock on tear-down Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 167/542] ath10k: correct the tlv len of ath10k_wmi_tlv_op_gen_config_pno_start Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 177/542] net/wan/fsl_ucc_hdlc: reject muram offsets above 64K Sasha Levin
2020-02-14 15:42 ` [PATCH AUTOSEL 5.5 180/542] NFC: port100: Convert cpu_to_le16(le16_to_cpu(E1) + E2) to use le16_add_cpu() Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 191/542] enetc: remove variable 'tc_max_sized_frame' set but not used Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 207/542] Revert "nfp: abm: fix memory leak in nfp_abm_u32_knode_replace" Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 209/542] selftests/net: make so_txtime more robust to timer variance Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 212/542] samples/bpf: Set -fno-stack-protector when building BPF programs Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 213/542] r8169: check that Realtek PHY driver module is loaded Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 214/542] fore200e: Fix incorrect checks of NULL pointer dereference Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 215/542] isdn: don't mark kcapi_proc_exit as __exit Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 220/542] netfilter: nft_tunnel: add the missing ERSPAN_VERSION nla_policy Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 226/542] b43legacy: Fix -Wcast-function-type Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 227/542] ipw2x00: " Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 228/542] iwlegacy: " Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 229/542] rtlwifi: rtl_pci: " Sasha Levin
2020-02-14 15:43 ` [PATCH AUTOSEL 5.5 231/542] orinoco: avoid assertion in case of NULL pointer Sasha Levin
2020-02-14 15:44 ` [PATCH AUTOSEL 5.5 263/542] bpf: Print error message for bpftool cgroup show Sasha Levin
2020-02-14 15:44 ` [PATCH AUTOSEL 5.5 264/542] net: phy: realtek: add logging for the RGMII TX delay configuration Sasha Levin
2020-02-14 15:44 ` [PATCH AUTOSEL 5.5 266/542] net/wan/fsl_ucc_hdlc: remove set but not used variables 'ut_info' and 'ret' Sasha Levin
2020-02-14 15:44 ` [PATCH AUTOSEL 5.5 278/542] ice: add extra check for null Rx descriptor Sasha Levin
2020-02-14 15:44 ` [PATCH AUTOSEL 5.5 285/542] net: phy: fixed_phy: fix use-after-free when checking link GPIO Sasha Levin
2020-02-14 15:44 ` [PATCH AUTOSEL 5.5 286/542] tools lib api fs: Fix gcc9 stringop-truncation compilation error Sasha Levin
2020-02-14 15:44 ` [PATCH AUTOSEL 5.5 294/542] mlx5: work around high stack usage with gcc Sasha Levin
2020-02-14 15:45 ` [PATCH AUTOSEL 5.5 325/542] bnxt: Detach page from page pool before sending up the stack Sasha Levin
2020-02-14 15:45 ` [PATCH AUTOSEL 5.5 327/542] wan: ixp4xx_hss: fix compile-testing on 64-bit Sasha Levin
2020-02-14 15:45 ` [PATCH AUTOSEL 5.5 352/542] bpf: Return -EBADRQC for invalid map type in __bpf_tx_xdp_map Sasha Levin
2020-02-14 15:46 ` [PATCH AUTOSEL 5.5 386/542] netfilter: flowtable: restrict flow dissector match on meta ingress device Sasha Levin
2020-02-14 15:46 ` [PATCH AUTOSEL 5.5 401/542] enetc: Don't print from enetc_sched_speed_set when link goes down Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 438/542] bpf, btf: Always output invariant hit in pahole DWARF to BTF transform Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 440/542] sunrpc: Fix potential leaks in sunrpc_cache_unhash() Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 443/542] net/mlx5e: Fix printk format warning Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 461/542] selftests: bpf: Reset global state between reuseport test runs Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 471/542] ath10k: pci: Only dump ATH10K_MEM_REGION_TYPE_IOREG when safe Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 472/542] hostap: Adjust indentation in prism2_hostapd_add_sta Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 473/542] rtw88: fix potential NULL skb access in TX ISR Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 474/542] rtlwifi: rtl8821ae: remove unused variables Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 475/542] rtlwifi: rtl8192ee: " Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 476/542] rtlwifi: rtl8723ae: " Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 477/542] iwlegacy: ensure loop counter addr does not wrap and cause an infinite loop Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 482/542] bpf: map_seq_next should always increase position index Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 484/542] mwifiex: Fix possible buffer overflows in mwifiex_ret_wmm_get_status() Sasha Levin
2020-02-14 15:47 ` [PATCH AUTOSEL 5.5 485/542] mwifiex: Fix possible buffer overflows in mwifiex_cmd_append_vsie_tlv() Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 502/542] powerpc: Do not consider weak unresolved symbol relocations as bad Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 516/542] iwlwifi: mvm: Fix thermal zone registration Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 517/542] iwlwifi: mvm: avoid use after free for pmsr request Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 518/542] iwlwifi: mvm: Check the sta is not NULL in iwl_mvm_cfg_he_sta() Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 519/542] iwlwifi: mvm: fix TDLS discovery with the new firmware API Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 521/542] netdevsim: fix using uninitialized resources Sasha Levin
2020-02-14 15:48 ` Sasha Levin [this message]
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 523/542] netdevsim: fix panic in nsim_dev_take_snapshot_write() Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 524/542] netdevsim: use __GFP_NOWARN to avoid memalloc warning Sasha Levin
2020-02-14 16:23 ` Jakub Kicinski
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 535/542] i40e: Relax i40e_xsk_wakeup's return value when PF is busy Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 540/542] mlxsw: core: Add validation of hardware device types for MGPIR register Sasha Levin
2020-02-14 15:48 ` [PATCH AUTOSEL 5.5 541/542] mlxsw: spectrum_dpipe: Add missing error path Sasha Levin
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