From mboxrd@z Thu Jan 1 00:00:00 1970 From: Corinna Vinschen Date: Tue, 8 Mar 2022 16:49:48 +0100 Subject: [Intel-wired-lan] [PATCH v1 1/1] igc: Fix BUG: scheduling while atomic: kworker/u64:0/9/0x00000002 In-Reply-To: <20220308092422.2971655-1-sasha.neftin@intel.com> References: <20220308092422.2971655-1-sasha.neftin@intel.com> Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: Hi Sasha, On Mar 8 11:24, Sasha Neftin wrote: > Replace usleep_range() method with udelay() method to allow atomic contects > in low-level MDIO access functions. The commit message is a bit on the short end. It should probably quote the reproducer from the below Bugzilla, rather than just pointing to the Bugzilla, i.e., $ modprobe -r bonding $ modprobe -v bonding max_bonds=1 mode=1 miimon=100 use_carrier=0 $ ip link set bond0 up $ ifenslave bond0 eth0 eth1 leads to the following [shortened] kernel log: [ 120.198086] Voluntary context switch within RCU read-side critical section! [ 120.198093] WARNING: CPU: 3 PID: 10 at kernel/rcu/tree_plugin.h:318 rcu_note_context_switch+0x4ea/0x580 [ 120.207310] bond0: (slave ens5f0): Enslaving as a backup interface with a down link [ 120.229488] [...] [ 120.754723] Workqueue: bond0 bond_mii_monitor [bonding] [ 120.779106] RIP: 0010:rcu_note_context_switch+0x4ea/0x580 [ 120.803880] Code: 08 49 89 8e 40 08 00 00 4d 89 be 48 08 00 00 4d 89 07 e9 98 fe ff ff 48 c7 c7 48 83 94 b6 c6 05 74 3b e1 01 01 e8 35 fd 8a 00 <0f> 0b e9 67 fb ff ff 45 85 f6 0f 84 9e fe ff ff 4c 89 85 a8 00 00 [ 120.890778] RSP: 0018:ffffa2f5c01bbbc8 EFLAGS: 00010082 [ 120.915218] RAX: 0000000000000000 RBX: ffff938d6f8f1740 RCX: 0000000000000027 [ 120.948713] RDX: 0000000000000027 RSI: ffff938d6f8dfcc0 RDI: ffff938d6f8dfcc8 [ 120.982368] RBP: ffffa2f5c01bbc50 R08: 0000000000000000 R09: c0000000ffff7fff [ 121.016065] R10: 0000000000000001 R11: ffffa2f5c01bb9e0 R12: ffff938a022a9980 [ 121.049504] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000001 [ 121.082870] FS: 0000000000000000(0000) GS:ffff938d6f8c0000(0000) knlGS:0000000000000000 [ 121.121993] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 121.151532] CR2: 0000556901ea4f28 CR3: 0000000482810001 CR4: 00000000001706e0 [ 121.186337] Call Trace: [ 121.197543] [ 121.207444] __schedule+0x9a/0x7b0 [ 121.223316] ? hrtimer_start_range_ns+0x11d/0x300 [ 121.245293] schedule+0x41/0xc0 [ 121.259860] schedule_hrtimeout_range_clock+0x83/0x100 [ 121.283548] ? hrtimer_init_sleeper+0x80/0x80 [ 121.303830] usleep_range_state+0x5b/0x80 [ 121.322747] igc_read_phy_reg_gpy+0x90/0x180 [igc] [ 121.345249] igc_phy_has_link+0x7d/0x170 [igc] [ 121.365980] igc_check_for_copper_link+0x60/0xd0 [igc] [ 121.390260] igc_has_link+0x2a/0x80 [igc] [ 121.409093] igc_ethtool_get_link+0x24/0x30 [igc] [ 121.431248] bond_check_dev_link.isra.49+0x5a/0x120 [bonding] [ 121.458271] ? pick_next_task_fair+0x3e/0x3b0 [ 121.478749] ? put_prev_entity+0x22/0xe0 [ 121.497154] ? put_prev_task_fair+0x1b/0x30 [ 121.516903] bond_mii_monitor+0x107/0x540 [bonding] [...] > Fixes: 5586838fe9ce ("igc: Add code for PHY support") > Reported-by: Corinna Vinschen > Suggested-by: Dima Ruinskiy > Signed-off-by: Sasha Neftin > --- > drivers/net/ethernet/intel/igc/igc_phy.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/net/ethernet/intel/igc/igc_phy.c b/drivers/net/ethernet/intel/igc/igc_phy.c > index 40dbf4b43234..6961f65d36b9 100644 > --- a/drivers/net/ethernet/intel/igc/igc_phy.c > +++ b/drivers/net/ethernet/intel/igc/igc_phy.c > @@ -581,7 +581,7 @@ static s32 igc_read_phy_reg_mdic(struct igc_hw *hw, u32 offset, u16 *data) > * the lower time out > */ > for (i = 0; i < IGC_GEN_POLL_TIMEOUT; i++) { > - usleep_range(500, 1000); > + udelay(50); > mdic = rd32(IGC_MDIC); > if (mdic & IGC_MDIC_READY) > break; > @@ -638,7 +638,7 @@ static s32 igc_write_phy_reg_mdic(struct igc_hw *hw, u32 offset, u16 data) > * the lower time out > */ > for (i = 0; i < IGC_GEN_POLL_TIMEOUT; i++) { > - usleep_range(500, 1000); > + udelay(50); > mdic = rd32(IGC_MDIC); > if (mdic & IGC_MDIC_READY) > break; > -- > 2.30.2 Tested-by: Corinna Vinschen Thanks, Corinna