From: Piotr Skajewski piotrx.skajewski@intel.com
[ Upstream commit 1e53834ce541d4fe271cdcca7703e50be0a44f8a ]
It is possible to disable VFs while the PF driver is processing requests from the VF driver. This can result in a panic.
BUG: unable to handle kernel paging request at 000000000000106c PGD 0 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 8 PID: 0 Comm: swapper/8 Kdump: loaded Tainted: G I --------- - Hardware name: Dell Inc. PowerEdge R740/06WXJT, BIOS 2.8.2 08/27/2020 RIP: 0010:ixgbe_msg_task+0x4c8/0x1690 [ixgbe] Code: 00 00 48 8d 04 40 48 c1 e0 05 89 7c 24 24 89 fd 48 89 44 24 10 83 ff 01 0f 84 b8 04 00 00 4c 8b 64 24 10 4d 03 a5 48 22 00 00 <41> 80 7c 24 4c 00 0f 84 8a 03 00 00 0f b7 c7 83 f8 08 0f 84 8f 0a RSP: 0018:ffffb337869f8df8 EFLAGS: 00010002 RAX: 0000000000001020 RBX: 0000000000000000 RCX: 000000000000002b RDX: 0000000000000002 RSI: 0000000000000008 RDI: 0000000000000006 RBP: 0000000000000006 R08: 0000000000000002 R09: 0000000000029780 R10: 00006957d8f42832 R11: 0000000000000000 R12: 0000000000001020 R13: ffff8a00e8978ac0 R14: 000000000000002b R15: ffff8a00e8979c80 FS: 0000000000000000(0000) GS:ffff8a07dfd00000(0000) knlGS:00000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000000106c CR3: 0000000063e10004 CR4: 00000000007726e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <IRQ> ? ttwu_do_wakeup+0x19/0x140 ? try_to_wake_up+0x1cd/0x550 ? ixgbevf_update_xcast_mode+0x71/0xc0 [ixgbevf] ixgbe_msix_other+0x17e/0x310 [ixgbe] __handle_irq_event_percpu+0x40/0x180 handle_irq_event_percpu+0x30/0x80 handle_irq_event+0x36/0x53 handle_edge_irq+0x82/0x190 handle_irq+0x1c/0x30 do_IRQ+0x49/0xd0 common_interrupt+0xf/0xf
This can be eventually be reproduced with the following script:
while : do echo 63 > /sys/class/net/<devname>/device/sriov_numvfs sleep 1 echo 0 > /sys/class/net/<devname>/device/sriov_numvfs sleep 1 done
Add lock when disabling SR-IOV to prevent process VF mailbox communication.
Fixes: d773d1310625 ("ixgbe: Fix memory leak when SR-IOV VFs are direct assigned") Signed-off-by: Piotr Skajewski piotrx.skajewski@intel.com Tested-by: Marek Szlosek marek.szlosek@intel.com Signed-off-by: Tony Nguyen anthony.l.nguyen@intel.com Link: https://lore.kernel.org/r/20220715214456.2968711-1-anthony.l.nguyen@intel.co... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/intel/ixgbe/ixgbe.h | 1 + drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 3 +++ drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c | 6 ++++++ 3 files changed, 10 insertions(+)
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h index 921a4d977d65..8813b4dd6872 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h @@ -779,6 +779,7 @@ struct ixgbe_adapter { #ifdef CONFIG_IXGBE_IPSEC struct ixgbe_ipsec *ipsec; #endif /* CONFIG_IXGBE_IPSEC */ + spinlock_t vfs_lock; };
static inline int ixgbe_determine_xdp_q_idx(int cpu) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index c4a4954aa317..6c403f112d29 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -6402,6 +6402,9 @@ static int ixgbe_sw_init(struct ixgbe_adapter *adapter, /* n-tuple support exists, always init our spinlock */ spin_lock_init(&adapter->fdir_perfect_lock);
+ /* init spinlock to avoid concurrency of VF resources */ + spin_lock_init(&adapter->vfs_lock); + #ifdef CONFIG_IXGBE_DCB ixgbe_init_dcb(adapter); #endif diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c index d4e63f0644c3..a1e69c734863 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c @@ -205,10 +205,13 @@ void ixgbe_enable_sriov(struct ixgbe_adapter *adapter, unsigned int max_vfs) int ixgbe_disable_sriov(struct ixgbe_adapter *adapter) { unsigned int num_vfs = adapter->num_vfs, vf; + unsigned long flags; int rss;
+ spin_lock_irqsave(&adapter->vfs_lock, flags); /* set num VFs to 0 to prevent access to vfinfo */ adapter->num_vfs = 0; + spin_unlock_irqrestore(&adapter->vfs_lock, flags);
/* put the reference to all of the vf devices */ for (vf = 0; vf < num_vfs; ++vf) { @@ -1355,8 +1358,10 @@ static void ixgbe_rcv_ack_from_vf(struct ixgbe_adapter *adapter, u32 vf) void ixgbe_msg_task(struct ixgbe_adapter *adapter) { struct ixgbe_hw *hw = &adapter->hw; + unsigned long flags; u32 vf;
+ spin_lock_irqsave(&adapter->vfs_lock, flags); for (vf = 0; vf < adapter->num_vfs; vf++) { /* process any reset requests */ if (!ixgbe_check_for_rst(hw, vf)) @@ -1370,6 +1375,7 @@ void ixgbe_msg_task(struct ixgbe_adapter *adapter) if (!ixgbe_check_for_ack(hw, vf)) ixgbe_rcv_ack_from_vf(adapter, vf); } + spin_unlock_irqrestore(&adapter->vfs_lock, flags); }
static inline void ixgbe_ping_vf(struct ixgbe_adapter *adapter, int vf)