RE: [Intel-wired-lan] [PATCH iwl-net] i40e: Fix trying to free already-freed IRQ

Loktionov, Aleksandr
2024-09-04T21:00:39Z

> From: Intel-wired-lan <intel-wired-lan-bounces@osuosl.org> On Behalf
> Of YangHang Liu
> Sent: Wednesday, September 4, 2024 4:37 AM
> To: Kamal Heib <kheib@redhat.com>; Chao Yang <chayang@redhat.com>
> Cc: ivecera <ivecera@redhat.com>; netdev@vger.kernel.org; Jakub
> Kicinski <kuba@kernel.org>; Nguyen, Anthony L
> <anthony.l.nguyen@intel.com>; Kitszel, Przemyslaw
> <przemyslaw.kitszel@intel.com>; intel-wired-lan@lists.osuosl.org;
> Paolo Abeni <pabeni@redhat.com>; David S . Miller
> <davem@davemloft.net>
> Subject: Re: [Intel-wired-lan] [PATCH iwl-net] i40e: Fix trying to
> free already-freed IRQ
>
> This issue can be reproduced by hot-unplugging the INTx i40e PF.
>
> The Call Trace will disappear after using Kamal's fix.
>
> Tested-by: Yanghang Liu<yanghliu@redhat.com>
>
>
>
> On Wed, Sep 4, 2024 at 2:26 AM Kamal Heib <kheib@redhat.com> wrote:
> >
> > Avoid the following warning when trying to free an already freed
> IRQ,
> > The issue happens when trying to call i40e_remove() twice from two
> > different contexts which will lead to calling i40e_vsi_free_irq()
> > twice, Fix the issue by using a flag to mark that the IRQ has
> already been freed.
> >
> > i40e 0000:07:00.0: i40e_ptp_stop: removed PHC on enp7s0 ------------
> [
> > cut here ]------------ Trying to free already-free IRQ 0
> > WARNING: CPU: 2 PID: 12 at kernel/irq/manage.c:1868
> > __free_irq+0x1e3/0x350 Modules linked in: nft_fib_inet nft_fib_ipv4
> > nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6
> > nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6
> > nf_defrag_ipv4 rfkill ip_set nf_tables nfnetlink vfat fat
> > intel_rapl_msr intel_rapl_common kvm_amd ccp iTCO_wdt
> > iTCO_vendor_support kvm i2c_i801 pcspkr i40e lpc_ich virtio_gpu
> > i2c_smbus virtio_dma_buf drm_shmem_helper drm_kms_helper
> > virtio_balloon joydev drm fuse xfs libcrc32c ahci crct10dif_pclmul
> > libahci crc32_pclmul crc32c_intel virtio_net libata virtio_blk
> > ghash_clmulni_intel net_failover virtio_console failover serio_raw
> > dm_mirror dm_region_hash dm_log dm_mod
> > CPU: 2 PID: 12 Comm: kworker/u16:1 Kdump: loaded Not tainted
> > 5.14.0-478.el9.x86_64 #1 Hardware name: Red Hat KVM/RHEL, BIOS
> > edk2-20240524-1.el9 05/24/2024
> > Workqueue: kacpi_hotplug acpi_hotplug_work_fn
> > RIP: 0010:__free_irq+0x1e3/0x350
> > Code: 00 00 48 8b bb a8 01 00 00 e8 09 74 02 00 49 8b 7c 24 30 e8 8f
> > 7c 1d 00 eb 35 8b 74 24 04 48 c7 c7 50 a3 61 92 e8 cd 99 f6 ff <0f>
> 0b
> > 4c 89 fe 48 89 ef e8 30 aa b3 00 48 8b 43 40 48 8b 40 78 48
> > RSP: 0018:ffffb971c0077ac8 EFLAGS: 00010086
> > RAX: 0000000000000000 RBX: ffff8b594193ee00 RCX: 0000000000000027
> > RDX: 0000000000000027 RSI: 00000000ffff7fff RDI: ffff8b59bcf208c8
> > RBP: ffff8b594193eec4 R08: 0000000000000000 R09: ffffb971c0077970
> > R10: ffffb971c0077968 R11: ffffffff931e7c28 R12: ffff8b5944946000
> > R13: ffff8b594193ef80 R14: ffff8b5944946000 R15: 0000000000000246
> > FS: 0000000000000000(0000) GS:ffff8b59bcf00000(0000)
> > knlGS:0000000000000000
> > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> > CR2: 00007f11eb064000 CR3: 000000000ad40004 CR4: 0000000000770ef0
> > PKRU: 55555554
> > Call Trace:
> > <TASK>
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? show_trace_log_lvl+0x26e/0x2df
> > ? show_trace_log_lvl+0x26e/0x2df
> > ? free_irq+0x33/0x70
> > ? __free_irq+0x1e3/0x350
> > ? __warn+0x7e/0xd0
> > ? __free_irq+0x1e3/0x350
> > ? report_bug+0x100/0x140
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? handle_bug+0x3c/0x70
> > ? exc_invalid_op+0x14/0x70
> > ? asm_exc_invalid_op+0x16/0x20
> > ? __free_irq+0x1e3/0x350
> > ? __free_irq+0x1e3/0x350
> > free_irq+0x33/0x70
> > i40e_vsi_free_irq+0x19e/0x220 [i40e]
> > i40e_vsi_close+0x2b/0xc0 [i40e]
> > i40e_close+0x11/0x20 [i40e]
> > __dev_close_many+0x9e/0x110
> > dev_close_many+0x8b/0x140
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? free_pcppages_bulk+0xee/0x290
> > unregister_netdevice_many_notify+0x162/0x690
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > ? free_unref_page_commit+0x19a/0x310
> > unregister_netdevice_queue+0xd3/0x110
> > unregister_netdev+0x18/0x20
> > i40e_vsi_release+0x84/0x2e0 [i40e]
> > ? srso_alias_return_thunk+0x5/0xfbef5
> > i40e_remove+0x15c/0x430 [i40e]
> > pci_device_remove+0x3e/0xb0
> > device_release_driver_internal+0x193/0x200
> > pci_stop_bus_device+0x6c/0x90
> > pci_stop_and_remove_bus_device+0xe/0x20
> > disable_slot+0x49/0x90
> > acpiphp_disable_and_eject_slot+0x15/0x90
> > hotplug_event+0xea/0x210
> > ? __pfx_acpiphp_hotplug_notify+0x10/0x10
> > acpiphp_hotplug_notify+0x22/0x80
> > ? __pfx_acpiphp_hotplug_notify+0x10/0x10
> > acpi_device_hotplug+0xb8/0x210
> > acpi_hotplug_work_fn+0x1a/0x30
> > process_one_work+0x197/0x380
> > worker_thread+0x2fe/0x410
> > ? __pfx_worker_thread+0x10/0x10
> > kthread+0xe0/0x100
> > ? __pfx_kthread+0x10/0x10
> > ret_from_fork+0x2c/0x50
> > </TASK>
> > ---[ end trace 0000000000000000 ]---
> >
> > Fixes: 41c445ff0f48 ("i40e: main driver core")
> > Tested-by: YangHang Liu <yanghliu@redhat.com>
> > Signed-off-by: Kamal Heib <kheib@redhat.com>
> > ---
> > drivers/net/ethernet/intel/i40e/i40e.h | 1 +
> > drivers/net/ethernet/intel/i40e/i40e_main.c | 8 ++++++++
> > 2 files changed, 9 insertions(+)
> >
> > diff --git a/drivers/net/ethernet/intel/i40e/i40e.h
> > b/drivers/net/ethernet/intel/i40e/i40e.h
> > index d546567e0286..910415116995 100644
> > --- a/drivers/net/ethernet/intel/i40e/i40e.h
> > +++ b/drivers/net/ethernet/intel/i40e/i40e.h
> > @@ -865,6 +865,7 @@ struct i40e_vsi {
> > int num_q_vectors;
> > int base_vector;
> > bool irqs_ready;
> > + bool legacy_msi_irq_ready;
I'm against adding additional boolian var which can cause race conditions.
Use I40E_FLAG_MSIX_ENA or at least add additional bit and use interlock test_and_clean/test_and_set bit functions instead.

> >
> > u16 seid; /* HW index of this VSI (absolute
> index) */
> > u16 id; /* VSI number */
> > diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c
> > b/drivers/net/ethernet/intel/i40e/i40e_main.c
> > index cbcfada7b357..b39004a42df2 100644
> > --- a/drivers/net/ethernet/intel/i40e/i40e_main.c
> > +++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
> > @@ -4630,6 +4630,9 @@ static int i40e_vsi_request_irq(struct
> i40e_vsi *vsi, char *basename)
> > if (err)
> > dev_info(&pf->pdev->dev, "request_irq failed, Error
> > %d\n", err);
> >
> > + if (!test_bit(I40E_FLAG_MSIX_ENA, pf->flags) && !err)
> > + vsi->legacy_msi_irq_ready = true;
> > +
> > return err;
> > }
> >
> > @@ -5061,6 +5064,10 @@ static void i40e_vsi_free_irq(struct i40e_vsi
> *vsi)
> > }
> > }
> > } else {
> > + if (!vsi->legacy_msi_irq_ready)
> > + return;
> > +
> > + vsi->legacy_msi_irq_ready = false;
> > free_irq(pf->pdev->irq, pf);
> >
> > val = rd32(hw, I40E_PFINT_LNKLST0); @@ -11519,6
> > +11526,7 @@ static int i40e_vsi_mem_alloc(struct i40e_pf *pf, enum
> i40e_vsi_type type)
> > vsi->work_limit = I40E_DEFAULT_IRQ_WORK;
> > hash_init(vsi->mac_filter_hash);
> > vsi->irqs_ready = false;
> > + vsi->legacy_msi_irq_ready = false;
> >
> > if (type == I40E_VSI_MAIN) {
> > vsi->af_xdp_zc_qps = bitmap_zalloc(pf->num_lan_qps,
> > GFP_KERNEL);
> > --
> > 2.46.0
> >