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* stmmac and XDP/ZC issue
@ 2024-02-20 11:02 Kurt Kanzenbach
  2024-02-20 13:18 ` Serge Semin
  0 siblings, 1 reply; 10+ messages in thread
From: Kurt Kanzenbach @ 2024-02-20 11:02 UTC (permalink / raw)
  To: netdev; +Cc: Sebastian Andrzej Siewior, Song Yoong Siang

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Hello netdev community,

after updating to v6.8 kernel I've encountered an issue in the stmmac
driver.

I have an application which makes use of XDP zero-copy sockets. It works
on v6.7. On v6.8 it results in the stack trace shown below. The program
counter points to:

 - ./include/net/xdp_sock.h:192 and
 - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681

It seems to be caused by the XDP meta data patches. This one in
particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").

To reproduce:

 - Hardware: imx93
 - Run ptp4l/phc2sys
 - Configure Qbv, Rx steering, NAPI threading
 - Run my application using XDP/ZC on queue 1

Any idea what might be the issue here?

Thanks,
Kurt

Stack trace:

|[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
|[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
|[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
|[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
|[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
|[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
|[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
|[  255.822602] Mem abort info:
|[  255.822604]   ESR = 0x0000000096000044
|[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
|[  255.822613]   SET = 0, FnV = 0
|[  255.822616]   EA = 0, S1PTW = 0
|[  255.822618]   FSC = 0x04: level 0 translation fault
|[  255.822622] Data abort info:
|[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
|[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
|[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
|[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
|[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
|[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
|[  255.822655] Modules linked in:
|[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
|[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
|[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
|[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
|[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
|[  255.822696] sp : ffff800085ec3bc0
|[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
|[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
|[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
|[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
|[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
|[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
|[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
|[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
|[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
|[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
|[  255.822764] Call trace:
|[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
|[  255.822772]  stmmac_napi_poll_rxtx+0xc4/0xec0
|[  255.822778]  __napi_poll.constprop.0+0x40/0x220
|[  255.822785]  napi_threaded_poll+0xd8/0x228
|[  255.822790]  kthread+0x108/0x120
|[  255.822798]  ret_from_fork+0x10/0x20
|[  255.822808] Code: 910303e0 f9003be1 97ffdec0 f9403be1 (f9000020) 
|[  255.822812] ---[ end trace 0000000000000000 ]---
|[  255.822817] Kernel panic - not syncing: Oops: Fatal exception in interrupt
|[  255.822819] SMP: stopping secondary CPUs
|[  255.822827] Kernel Offset: disabled
|[  255.822829] CPU features: 0x0,c0000000,4002814a,2100720b
|[  255.822834] Memory Limit: none
|[  256.062429] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---

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^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-20 11:02 stmmac and XDP/ZC issue Kurt Kanzenbach
@ 2024-02-20 13:18 ` Serge Semin
  2024-02-20 14:43   ` Maciej Fijalkowski
  0 siblings, 1 reply; 10+ messages in thread
From: Serge Semin @ 2024-02-20 13:18 UTC (permalink / raw)
  To: Kurt Kanzenbach
  Cc: netdev, Sebastian Andrzej Siewior, Song Yoong Siang,
	Stanislav Fomichev, Alexei Starovoitov

Hi Kurt

On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
> Hello netdev community,
> 
> after updating to v6.8 kernel I've encountered an issue in the stmmac
> driver.
> 
> I have an application which makes use of XDP zero-copy sockets. It works
> on v6.7. On v6.8 it results in the stack trace shown below. The program
> counter points to:
> 
>  - ./include/net/xdp_sock.h:192 and
>  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
> 
> It seems to be caused by the XDP meta data patches. This one in
> particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
> 
> To reproduce:
> 
>  - Hardware: imx93
>  - Run ptp4l/phc2sys
>  - Configure Qbv, Rx steering, NAPI threading
>  - Run my application using XDP/ZC on queue 1
> 
> Any idea what might be the issue here?
> 
> Thanks,
> Kurt
> 
> Stack trace:
> 
> |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
> |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
> |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
> |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
> |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
> |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
> |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> |[  255.822602] Mem abort info:
> |[  255.822604]   ESR = 0x0000000096000044
> |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
> |[  255.822613]   SET = 0, FnV = 0
> |[  255.822616]   EA = 0, S1PTW = 0
> |[  255.822618]   FSC = 0x04: level 0 translation fault
> |[  255.822622] Data abort info:
> |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
> |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
> |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
> |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
> |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
> |[  255.822655] Modules linked in:
> |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
> |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
> |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
> |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
> |[  255.822696] sp : ffff800085ec3bc0
> |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
> |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
> |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
> |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
> |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
> |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
> |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
> |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
> |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
> |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
> |[  255.822764] Call trace:
> |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
> |[  255.822772]  stmmac_napi_poll_rxtx+0xc4/0xec0
> |[  255.822778]  __napi_poll.constprop.0+0x40/0x220
> |[  255.822785]  napi_threaded_poll+0xd8/0x228
> |[  255.822790]  kthread+0x108/0x120
> |[  255.822798]  ret_from_fork+0x10/0x20
> |[  255.822808] Code: 910303e0 f9003be1 97ffdec0 f9403be1 (f9000020) 
> |[  255.822812] ---[ end trace 0000000000000000 ]---
> |[  255.822817] Kernel panic - not syncing: Oops: Fatal exception in interrupt
> |[  255.822819] SMP: stopping secondary CPUs
> |[  255.822827] Kernel Offset: disabled
> |[  255.822829] CPU features: 0x0,c0000000,4002814a,2100720b
> |[  255.822834] Memory Limit: none
> |[  256.062429] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---

Just confirmed the same problem on my MIPS-based SoC:

Device #1:
$ ifconfig eth2 192.168.2.2 up
$ pktgen.sh -v -i eth2 -d 192.168.2.3 -m 4C:A5:15:59:A6:86 -n 0 -s 1496

Device #2:
$ mount -t bpf none /sys/fs/bpf/
$ sysctl -w net.core.bpf_jit_enable=1
$ ifconfig eth0 192.168.2.3 up
$ xdp-bench tx eth0
...
[  559.663885] CPU 0 Unable to handle kernel paging request at virtual address 00000000, epc == 809a81e0, ra == 809a81dc
[  559.675786] Oops[#1]:
[  559.678324] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.8.0-rc3-bt1-00322-gb2c1210b8fe6-dirty #2176
[  559.695824] $ 0   : 00000000 00000001 00000000 00000000
[  559.701676] $ 4   : eb019c48 00000000 bf054000 81ddfe53
[  559.707524] $ 8   : 00000000 84ea05c0 00000000 00000000
[  559.713372] $12   : 00000000 0000002e 816e9d00 81080000
[  559.719221] $16   : 00000002 a254c020 00000000 00000000
[  559.725069] $20   : 84ea05c0 00000000 852b8000 00000040
[  559.730917] $24   : 00000000 00000000
[  559.736766] $28   : 815d8000 81ddfd88 84ea05c0 809a81dc
[  559.742615] Hi    : 00000007
[  559.745826] Lo    : 00000000
[  559.749029] epc   : 809a81e0 stmmac_tx_clean+0x9f8/0xd64
[  559.754974] ra    : 809a81dc stmmac_tx_clean+0x9f4/0xd64
[  559.760909] Status: 10000003 KERNEL EXL IE
[  559.765588] Cause : 0080040c (ExcCode 03)
[  559.770063] BadVA : 00000000
[  559.773266] PrId  : 0001a830
[  559.777740] Modules linked in:
[  559.781150] Process swapper/0 (pid: 0, threadinfo=9e75df13, task=e559c9e5, tls=00000000)
[  559.790194] Stack : 00000001 00000001 00003138 00000001 001a07f2 4696b1a6 00000000 00000000
[  559.799552]         00000000 00000001 00000000 81080000 00000001 00000000 84ea0b40 84ea2880
[  559.808909]         84ea0e20 00000000 00000000 00000001 81600000 81ddfe53 810d6bcc 817b0000
[  559.818265]         815d8000 81ddfe10 0000012c 80e83fd4 84ea05c0 a254c020 00000000 80142518
[  559.827622]         00800400 eb019c48 81600000 00000040 81ddfebc 84ea05c0 00000000 84ea1320
[  559.836979]         ...
[  559.839710] Call Trace:
[  559.842435] [<809a81e0>] stmmac_tx_clean+0x9f8/0xd64
[  559.847985] [<809a8610>] stmmac_napi_poll_tx+0xc4/0x18c
[  559.858885] [<80b2db94>] net_rx_action+0x128/0x288
[  559.864232] [<80e84d48>] __do_softirq+0x134/0x4e0
[  559.869489] [<80142484>] irq_exit+0xd4/0x138
[  559.874261] [<807cc768>] __gic_irq_dispatch+0x154/0x1f0
[  559.880101] [<80102d50>] except_vec_vi_end+0xc4/0xd0
[  559.885641] [<80e78884>] default_idle_call+0x64/0x168
[  559.891288] [<801975c4>] do_idle+0xf4/0x198
[  559.895965] [<80197990>] cpu_startup_entry+0x30/0x40
[  559.901513] [<80e78c1c>] kernel_init+0x0/0x120
[  559.906477] 
[  559.908126] Code: 0c2682db  afa50048  8fa50048 <aca20000> aca30004  1000fded  8fc208b0  8fc308ac  0000a825 
[  559.919047] 
[  559.920734] ---[ end trace 0000000000000000 ]---
[  559.925908] Kernel panic - not syncing: Fatal exception in interrupt

No problem has been spotted for the XDP drop and pass benches.

As you pointed out reverting the commit 1347b419318d ("net: stmmac:
Add Tx HWTS support to XDP ZC") fixes the bug.

-Serge(y)


^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-20 13:18 ` Serge Semin
@ 2024-02-20 14:43   ` Maciej Fijalkowski
  2024-02-20 21:57     ` Stanislav Fomichev
  0 siblings, 1 reply; 10+ messages in thread
From: Maciej Fijalkowski @ 2024-02-20 14:43 UTC (permalink / raw)
  To: Serge Semin
  Cc: Kurt Kanzenbach, netdev, Sebastian Andrzej Siewior,
	Song Yoong Siang, Stanislav Fomichev, Alexei Starovoitov

On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
> Hi Kurt
> 
> On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
> > Hello netdev community,
> > 
> > after updating to v6.8 kernel I've encountered an issue in the stmmac
> > driver.
> > 
> > I have an application which makes use of XDP zero-copy sockets. It works
> > on v6.7. On v6.8 it results in the stack trace shown below. The program
> > counter points to:
> > 
> >  - ./include/net/xdp_sock.h:192 and
> >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
> > 
> > It seems to be caused by the XDP meta data patches. This one in
> > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
> > 
> > To reproduce:
> > 
> >  - Hardware: imx93
> >  - Run ptp4l/phc2sys
> >  - Configure Qbv, Rx steering, NAPI threading
> >  - Run my application using XDP/ZC on queue 1
> > 
> > Any idea what might be the issue here?
> > 
> > Thanks,
> > Kurt
> > 
> > Stack trace:
> > 
> > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
> > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
> > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
> > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
> > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
> > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
> > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> > |[  255.822602] Mem abort info:
> > |[  255.822604]   ESR = 0x0000000096000044
> > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
> > |[  255.822613]   SET = 0, FnV = 0
> > |[  255.822616]   EA = 0, S1PTW = 0
> > |[  255.822618]   FSC = 0x04: level 0 translation fault
> > |[  255.822622] Data abort info:
> > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
> > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
> > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
> > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
> > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
> > |[  255.822655] Modules linked in:
> > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
> > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
> > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
> > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
> > |[  255.822696] sp : ffff800085ec3bc0
> > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
> > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
> > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
> > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
> > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
> > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
> > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
> > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
> > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
> > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
> > |[  255.822764] Call trace:
> > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38

Shouldn't xsk_tx_metadata_complete() be called only when corresponding
buf_type is STMMAC_TXBUF_T_XSK_TX?

> > |[  255.822772]  stmmac_napi_poll_rxtx+0xc4/0xec0
> > |[  255.822778]  __napi_poll.constprop.0+0x40/0x220
> > |[  255.822785]  napi_threaded_poll+0xd8/0x228
> > |[  255.822790]  kthread+0x108/0x120
> > |[  255.822798]  ret_from_fork+0x10/0x20
> > |[  255.822808] Code: 910303e0 f9003be1 97ffdec0 f9403be1 (f9000020) 
> > |[  255.822812] ---[ end trace 0000000000000000 ]---
> > |[  255.822817] Kernel panic - not syncing: Oops: Fatal exception in interrupt
> > |[  255.822819] SMP: stopping secondary CPUs
> > |[  255.822827] Kernel Offset: disabled
> > |[  255.822829] CPU features: 0x0,c0000000,4002814a,2100720b
> > |[  255.822834] Memory Limit: none
> > |[  256.062429] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---
> 
> Just confirmed the same problem on my MIPS-based SoC:
> 
> Device #1:
> $ ifconfig eth2 192.168.2.2 up
> $ pktgen.sh -v -i eth2 -d 192.168.2.3 -m 4C:A5:15:59:A6:86 -n 0 -s 1496
> 
> Device #2:
> $ mount -t bpf none /sys/fs/bpf/
> $ sysctl -w net.core.bpf_jit_enable=1
> $ ifconfig eth0 192.168.2.3 up
> $ xdp-bench tx eth0
> ...
> [  559.663885] CPU 0 Unable to handle kernel paging request at virtual address 00000000, epc == 809a81e0, ra == 809a81dc
> [  559.675786] Oops[#1]:
> [  559.678324] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.8.0-rc3-bt1-00322-gb2c1210b8fe6-dirty #2176
> [  559.695824] $ 0   : 00000000 00000001 00000000 00000000
> [  559.701676] $ 4   : eb019c48 00000000 bf054000 81ddfe53
> [  559.707524] $ 8   : 00000000 84ea05c0 00000000 00000000
> [  559.713372] $12   : 00000000 0000002e 816e9d00 81080000
> [  559.719221] $16   : 00000002 a254c020 00000000 00000000
> [  559.725069] $20   : 84ea05c0 00000000 852b8000 00000040
> [  559.730917] $24   : 00000000 00000000
> [  559.736766] $28   : 815d8000 81ddfd88 84ea05c0 809a81dc
> [  559.742615] Hi    : 00000007
> [  559.745826] Lo    : 00000000
> [  559.749029] epc   : 809a81e0 stmmac_tx_clean+0x9f8/0xd64
> [  559.754974] ra    : 809a81dc stmmac_tx_clean+0x9f4/0xd64
> [  559.760909] Status: 10000003 KERNEL EXL IE
> [  559.765588] Cause : 0080040c (ExcCode 03)
> [  559.770063] BadVA : 00000000
> [  559.773266] PrId  : 0001a830
> [  559.777740] Modules linked in:
> [  559.781150] Process swapper/0 (pid: 0, threadinfo=9e75df13, task=e559c9e5, tls=00000000)
> [  559.790194] Stack : 00000001 00000001 00003138 00000001 001a07f2 4696b1a6 00000000 00000000
> [  559.799552]         00000000 00000001 00000000 81080000 00000001 00000000 84ea0b40 84ea2880
> [  559.808909]         84ea0e20 00000000 00000000 00000001 81600000 81ddfe53 810d6bcc 817b0000
> [  559.818265]         815d8000 81ddfe10 0000012c 80e83fd4 84ea05c0 a254c020 00000000 80142518
> [  559.827622]         00800400 eb019c48 81600000 00000040 81ddfebc 84ea05c0 00000000 84ea1320
> [  559.836979]         ...
> [  559.839710] Call Trace:
> [  559.842435] [<809a81e0>] stmmac_tx_clean+0x9f8/0xd64
> [  559.847985] [<809a8610>] stmmac_napi_poll_tx+0xc4/0x18c
> [  559.858885] [<80b2db94>] net_rx_action+0x128/0x288
> [  559.864232] [<80e84d48>] __do_softirq+0x134/0x4e0
> [  559.869489] [<80142484>] irq_exit+0xd4/0x138
> [  559.874261] [<807cc768>] __gic_irq_dispatch+0x154/0x1f0
> [  559.880101] [<80102d50>] except_vec_vi_end+0xc4/0xd0
> [  559.885641] [<80e78884>] default_idle_call+0x64/0x168
> [  559.891288] [<801975c4>] do_idle+0xf4/0x198
> [  559.895965] [<80197990>] cpu_startup_entry+0x30/0x40
> [  559.901513] [<80e78c1c>] kernel_init+0x0/0x120
> [  559.906477] 
> [  559.908126] Code: 0c2682db  afa50048  8fa50048 <aca20000> aca30004  1000fded  8fc208b0  8fc308ac  0000a825 
> [  559.919047] 
> [  559.920734] ---[ end trace 0000000000000000 ]---
> [  559.925908] Kernel panic - not syncing: Fatal exception in interrupt
> 
> No problem has been spotted for the XDP drop and pass benches.
> 
> As you pointed out reverting the commit 1347b419318d ("net: stmmac:
> Add Tx HWTS support to XDP ZC") fixes the bug.
> 
> -Serge(y)
> 
> 

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-20 14:43   ` Maciej Fijalkowski
@ 2024-02-20 21:57     ` Stanislav Fomichev
  2024-02-21  7:13       ` Kurt Kanzenbach
  0 siblings, 1 reply; 10+ messages in thread
From: Stanislav Fomichev @ 2024-02-20 21:57 UTC (permalink / raw)
  To: Maciej Fijalkowski
  Cc: Serge Semin, Kurt Kanzenbach, netdev, Sebastian Andrzej Siewior,
	Song Yoong Siang, Alexei Starovoitov

On Tue, Feb 20, 2024 at 6:43 AM Maciej Fijalkowski
<maciej.fijalkowski@intel.com> wrote:
>
> On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
> > Hi Kurt
> >
> > On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
> > > Hello netdev community,
> > >
> > > after updating to v6.8 kernel I've encountered an issue in the stmmac
> > > driver.
> > >
> > > I have an application which makes use of XDP zero-copy sockets. It works
> > > on v6.7. On v6.8 it results in the stack trace shown below. The program
> > > counter points to:
> > >
> > >  - ./include/net/xdp_sock.h:192 and
> > >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
> > >
> > > It seems to be caused by the XDP meta data patches. This one in
> > > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
> > >
> > > To reproduce:
> > >
> > >  - Hardware: imx93
> > >  - Run ptp4l/phc2sys
> > >  - Configure Qbv, Rx steering, NAPI threading
> > >  - Run my application using XDP/ZC on queue 1
> > >
> > > Any idea what might be the issue here?
> > >
> > > Thanks,
> > > Kurt
> > >
> > > Stack trace:
> > >
> > > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
> > > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
> > > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
> > > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
> > > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
> > > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
> > > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> > > |[  255.822602] Mem abort info:
> > > |[  255.822604]   ESR = 0x0000000096000044
> > > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
> > > |[  255.822613]   SET = 0, FnV = 0
> > > |[  255.822616]   EA = 0, S1PTW = 0
> > > |[  255.822618]   FSC = 0x04: level 0 translation fault
> > > |[  255.822622] Data abort info:
> > > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
> > > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
> > > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> > > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
> > > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
> > > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
> > > |[  255.822655] Modules linked in:
> > > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
> > > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
> > > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> > > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
> > > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
> > > |[  255.822696] sp : ffff800085ec3bc0
> > > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
> > > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
> > > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
> > > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
> > > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
> > > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
> > > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
> > > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
> > > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
> > > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
> > > |[  255.822764] Call trace:
> > > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
>
> Shouldn't xsk_tx_metadata_complete() be called only when corresponding
> buf_type is STMMAC_TXBUF_T_XSK_TX?

+1. I'm assuming Serge isn't enabling it explicitly, so none of the
metadata stuff should trigger in this case.

> > > |[  255.822772]  stmmac_napi_poll_rxtx+0xc4/0xec0
> > > |[  255.822778]  __napi_poll.constprop.0+0x40/0x220
> > > |[  255.822785]  napi_threaded_poll+0xd8/0x228
> > > |[  255.822790]  kthread+0x108/0x120
> > > |[  255.822798]  ret_from_fork+0x10/0x20
> > > |[  255.822808] Code: 910303e0 f9003be1 97ffdec0 f9403be1 (f9000020)
> > > |[  255.822812] ---[ end trace 0000000000000000 ]---
> > > |[  255.822817] Kernel panic - not syncing: Oops: Fatal exception in interrupt
> > > |[  255.822819] SMP: stopping secondary CPUs
> > > |[  255.822827] Kernel Offset: disabled
> > > |[  255.822829] CPU features: 0x0,c0000000,4002814a,2100720b
> > > |[  255.822834] Memory Limit: none
> > > |[  256.062429] ---[ end Kernel panic - not syncing: Oops: Fatal exception in interrupt ]---
> >
> > Just confirmed the same problem on my MIPS-based SoC:
> >
> > Device #1:
> > $ ifconfig eth2 192.168.2.2 up
> > $ pktgen.sh -v -i eth2 -d 192.168.2.3 -m 4C:A5:15:59:A6:86 -n 0 -s 1496
> >
> > Device #2:
> > $ mount -t bpf none /sys/fs/bpf/
> > $ sysctl -w net.core.bpf_jit_enable=1
> > $ ifconfig eth0 192.168.2.3 up
> > $ xdp-bench tx eth0
> > ...
> > [  559.663885] CPU 0 Unable to handle kernel paging request at virtual address 00000000, epc == 809a81e0, ra == 809a81dc
> > [  559.675786] Oops[#1]:
> > [  559.678324] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.8.0-rc3-bt1-00322-gb2c1210b8fe6-dirty #2176
> > [  559.695824] $ 0   : 00000000 00000001 00000000 00000000
> > [  559.701676] $ 4   : eb019c48 00000000 bf054000 81ddfe53
> > [  559.707524] $ 8   : 00000000 84ea05c0 00000000 00000000
> > [  559.713372] $12   : 00000000 0000002e 816e9d00 81080000
> > [  559.719221] $16   : 00000002 a254c020 00000000 00000000
> > [  559.725069] $20   : 84ea05c0 00000000 852b8000 00000040
> > [  559.730917] $24   : 00000000 00000000
> > [  559.736766] $28   : 815d8000 81ddfd88 84ea05c0 809a81dc
> > [  559.742615] Hi    : 00000007
> > [  559.745826] Lo    : 00000000
> > [  559.749029] epc   : 809a81e0 stmmac_tx_clean+0x9f8/0xd64
> > [  559.754974] ra    : 809a81dc stmmac_tx_clean+0x9f4/0xd64
> > [  559.760909] Status: 10000003 KERNEL EXL IE
> > [  559.765588] Cause : 0080040c (ExcCode 03)
> > [  559.770063] BadVA : 00000000
> > [  559.773266] PrId  : 0001a830
> > [  559.777740] Modules linked in:
> > [  559.781150] Process swapper/0 (pid: 0, threadinfo=9e75df13, task=e559c9e5, tls=00000000)
> > [  559.790194] Stack : 00000001 00000001 00003138 00000001 001a07f2 4696b1a6 00000000 00000000
> > [  559.799552]         00000000 00000001 00000000 81080000 00000001 00000000 84ea0b40 84ea2880
> > [  559.808909]         84ea0e20 00000000 00000000 00000001 81600000 81ddfe53 810d6bcc 817b0000
> > [  559.818265]         815d8000 81ddfe10 0000012c 80e83fd4 84ea05c0 a254c020 00000000 80142518
> > [  559.827622]         00800400 eb019c48 81600000 00000040 81ddfebc 84ea05c0 00000000 84ea1320
> > [  559.836979]         ...
> > [  559.839710] Call Trace:
> > [  559.842435] [<809a81e0>] stmmac_tx_clean+0x9f8/0xd64
> > [  559.847985] [<809a8610>] stmmac_napi_poll_tx+0xc4/0x18c
> > [  559.858885] [<80b2db94>] net_rx_action+0x128/0x288
> > [  559.864232] [<80e84d48>] __do_softirq+0x134/0x4e0
> > [  559.869489] [<80142484>] irq_exit+0xd4/0x138
> > [  559.874261] [<807cc768>] __gic_irq_dispatch+0x154/0x1f0
> > [  559.880101] [<80102d50>] except_vec_vi_end+0xc4/0xd0
> > [  559.885641] [<80e78884>] default_idle_call+0x64/0x168
> > [  559.891288] [<801975c4>] do_idle+0xf4/0x198
> > [  559.895965] [<80197990>] cpu_startup_entry+0x30/0x40
> > [  559.901513] [<80e78c1c>] kernel_init+0x0/0x120
> > [  559.906477]
> > [  559.908126] Code: 0c2682db  afa50048  8fa50048 <aca20000> aca30004  1000fded  8fc208b0  8fc308ac  0000a825
> > [  559.919047]
> > [  559.920734] ---[ end trace 0000000000000000 ]---
> > [  559.925908] Kernel panic - not syncing: Fatal exception in interrupt
> >
> > No problem has been spotted for the XDP drop and pass benches.
> >
> > As you pointed out reverting the commit 1347b419318d ("net: stmmac:
> > Add Tx HWTS support to XDP ZC") fixes the bug.
> >
> > -Serge(y)
> >
> >

^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-20 21:57     ` Stanislav Fomichev
@ 2024-02-21  7:13       ` Kurt Kanzenbach
  2024-02-21  9:21         ` Kurt Kanzenbach
  0 siblings, 1 reply; 10+ messages in thread
From: Kurt Kanzenbach @ 2024-02-21  7:13 UTC (permalink / raw)
  To: Stanislav Fomichev, Maciej Fijalkowski
  Cc: Serge Semin, netdev, Sebastian Andrzej Siewior, Song Yoong Siang,
	Alexei Starovoitov

[-- Attachment #1: Type: text/plain, Size: 4577 bytes --]

On Tue Feb 20 2024, Stanislav Fomichev wrote:
> On Tue, Feb 20, 2024 at 6:43 AM Maciej Fijalkowski
> <maciej.fijalkowski@intel.com> wrote:
>>
>> On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
>> > Hi Kurt
>> >
>> > On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
>> > > Hello netdev community,
>> > >
>> > > after updating to v6.8 kernel I've encountered an issue in the stmmac
>> > > driver.
>> > >
>> > > I have an application which makes use of XDP zero-copy sockets. It works
>> > > on v6.7. On v6.8 it results in the stack trace shown below. The program
>> > > counter points to:
>> > >
>> > >  - ./include/net/xdp_sock.h:192 and
>> > >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
>> > >
>> > > It seems to be caused by the XDP meta data patches. This one in
>> > > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
>> > >
>> > > To reproduce:
>> > >
>> > >  - Hardware: imx93
>> > >  - Run ptp4l/phc2sys
>> > >  - Configure Qbv, Rx steering, NAPI threading
>> > >  - Run my application using XDP/ZC on queue 1
>> > >
>> > > Any idea what might be the issue here?
>> > >
>> > > Thanks,
>> > > Kurt
>> > >
>> > > Stack trace:
>> > >
>> > > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
>> > > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
>> > > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
>> > > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
>> > > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
>> > > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
>> > > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
>> > > |[  255.822602] Mem abort info:
>> > > |[  255.822604]   ESR = 0x0000000096000044
>> > > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
>> > > |[  255.822613]   SET = 0, FnV = 0
>> > > |[  255.822616]   EA = 0, S1PTW = 0
>> > > |[  255.822618]   FSC = 0x04: level 0 translation fault
>> > > |[  255.822622] Data abort info:
>> > > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
>> > > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
>> > > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
>> > > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
>> > > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
>> > > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
>> > > |[  255.822655] Modules linked in:
>> > > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
>> > > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
>> > > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>> > > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
>> > > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
>> > > |[  255.822696] sp : ffff800085ec3bc0
>> > > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
>> > > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
>> > > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
>> > > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
>> > > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
>> > > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
>> > > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
>> > > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
>> > > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
>> > > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
>> > > |[  255.822764] Call trace:
>> > > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
>>
>> Shouldn't xsk_tx_metadata_complete() be called only when corresponding
>> buf_type is STMMAC_TXBUF_T_XSK_TX?
>
> +1. I'm assuming Serge isn't enabling it explicitly, so none of the
> metadata stuff should trigger in this case.

The only other user of xsk_tx_metadata_complete() in mlx5 guards it with
xp_tx_metadata_enabled(). Seems like that's missing in stmmac?

Thanks,
Kurt

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^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-21  7:13       ` Kurt Kanzenbach
@ 2024-02-21  9:21         ` Kurt Kanzenbach
  2024-02-21 15:59           ` Maciej Fijalkowski
  0 siblings, 1 reply; 10+ messages in thread
From: Kurt Kanzenbach @ 2024-02-21  9:21 UTC (permalink / raw)
  To: Stanislav Fomichev, Maciej Fijalkowski
  Cc: Serge Semin, netdev, Sebastian Andrzej Siewior, Song Yoong Siang,
	Alexei Starovoitov

[-- Attachment #1: Type: text/plain, Size: 6659 bytes --]

On Wed Feb 21 2024, Kurt Kanzenbach wrote:
> On Tue Feb 20 2024, Stanislav Fomichev wrote:
>> On Tue, Feb 20, 2024 at 6:43 AM Maciej Fijalkowski
>> <maciej.fijalkowski@intel.com> wrote:
>>>
>>> On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
>>> > Hi Kurt
>>> >
>>> > On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
>>> > > Hello netdev community,
>>> > >
>>> > > after updating to v6.8 kernel I've encountered an issue in the stmmac
>>> > > driver.
>>> > >
>>> > > I have an application which makes use of XDP zero-copy sockets. It works
>>> > > on v6.7. On v6.8 it results in the stack trace shown below. The program
>>> > > counter points to:
>>> > >
>>> > >  - ./include/net/xdp_sock.h:192 and
>>> > >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
>>> > >
>>> > > It seems to be caused by the XDP meta data patches. This one in
>>> > > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
>>> > >
>>> > > To reproduce:
>>> > >
>>> > >  - Hardware: imx93
>>> > >  - Run ptp4l/phc2sys
>>> > >  - Configure Qbv, Rx steering, NAPI threading
>>> > >  - Run my application using XDP/ZC on queue 1
>>> > >
>>> > > Any idea what might be the issue here?
>>> > >
>>> > > Thanks,
>>> > > Kurt
>>> > >
>>> > > Stack trace:
>>> > >
>>> > > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
>>> > > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
>>> > > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
>>> > > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
>>> > > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
>>> > > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
>>> > > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
>>> > > |[  255.822602] Mem abort info:
>>> > > |[  255.822604]   ESR = 0x0000000096000044
>>> > > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
>>> > > |[  255.822613]   SET = 0, FnV = 0
>>> > > |[  255.822616]   EA = 0, S1PTW = 0
>>> > > |[  255.822618]   FSC = 0x04: level 0 translation fault
>>> > > |[  255.822622] Data abort info:
>>> > > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
>>> > > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
>>> > > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
>>> > > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
>>> > > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
>>> > > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
>>> > > |[  255.822655] Modules linked in:
>>> > > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
>>> > > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
>>> > > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>>> > > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
>>> > > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
>>> > > |[  255.822696] sp : ffff800085ec3bc0
>>> > > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
>>> > > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
>>> > > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
>>> > > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
>>> > > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
>>> > > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
>>> > > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
>>> > > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
>>> > > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
>>> > > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
>>> > > |[  255.822764] Call trace:
>>> > > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
>>>
>>> Shouldn't xsk_tx_metadata_complete() be called only when corresponding
>>> buf_type is STMMAC_TXBUF_T_XSK_TX?
>>
>> +1. I'm assuming Serge isn't enabling it explicitly, so none of the
>> metadata stuff should trigger in this case.
>
> The only other user of xsk_tx_metadata_complete() in mlx5 guards it with
> xp_tx_metadata_enabled(). Seems like that's missing in stmmac?

Well, the following patch seems to help:

commit e85ab4b97b4d6e50036435ac9851b876c221f580
Author: Kurt Kanzenbach <kurt@linutronix.de>
Date:   Wed Feb 21 08:18:15 2024 +0100

    net: stmmac: Complete meta data only when enabled
    
    Currently using XDP sockets on stmmac results in a kernel crash:
    
    |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
    |[...]
    |[  255.822764] Call trace:
    |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
    
    The program counter indicates xsk_tx_metadata_complete(). However, this
    function shouldn't be called unless metadata is actually enabled.
    
    Tested on imx93.
    
    Fixes: 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC")
    Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 9df27f03a8cb..77c62b26342d 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2678,9 +2678,10 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue,
                                        .desc = p,
                                };
 
-                               xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
-                                                        &stmmac_xsk_tx_metadata_ops,
-                                                        &tx_compl);
+                               if (xp_tx_metadata_enabled(tx_q->xsk_pool))
+                                       xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
+                                                                &stmmac_xsk_tx_metadata_ops,
+                                                                &tx_compl);
                        }
                }

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 861 bytes --]

^ permalink raw reply related	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-21  9:21         ` Kurt Kanzenbach
@ 2024-02-21 15:59           ` Maciej Fijalkowski
  2024-02-21 17:20             ` Serge Semin
  0 siblings, 1 reply; 10+ messages in thread
From: Maciej Fijalkowski @ 2024-02-21 15:59 UTC (permalink / raw)
  To: Kurt Kanzenbach
  Cc: Stanislav Fomichev, Serge Semin, netdev,
	Sebastian Andrzej Siewior, Song Yoong Siang, Alexei Starovoitov

On Wed, Feb 21, 2024 at 10:21:04AM +0100, Kurt Kanzenbach wrote:
> On Wed Feb 21 2024, Kurt Kanzenbach wrote:
> > On Tue Feb 20 2024, Stanislav Fomichev wrote:
> >> On Tue, Feb 20, 2024 at 6:43 AM Maciej Fijalkowski
> >> <maciej.fijalkowski@intel.com> wrote:
> >>>
> >>> On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
> >>> > Hi Kurt
> >>> >
> >>> > On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
> >>> > > Hello netdev community,
> >>> > >
> >>> > > after updating to v6.8 kernel I've encountered an issue in the stmmac
> >>> > > driver.
> >>> > >
> >>> > > I have an application which makes use of XDP zero-copy sockets. It works
> >>> > > on v6.7. On v6.8 it results in the stack trace shown below. The program
> >>> > > counter points to:
> >>> > >
> >>> > >  - ./include/net/xdp_sock.h:192 and
> >>> > >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
> >>> > >
> >>> > > It seems to be caused by the XDP meta data patches. This one in
> >>> > > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
> >>> > >
> >>> > > To reproduce:
> >>> > >
> >>> > >  - Hardware: imx93
> >>> > >  - Run ptp4l/phc2sys
> >>> > >  - Configure Qbv, Rx steering, NAPI threading
> >>> > >  - Run my application using XDP/ZC on queue 1
> >>> > >
> >>> > > Any idea what might be the issue here?
> >>> > >
> >>> > > Thanks,
> >>> > > Kurt
> >>> > >
> >>> > > Stack trace:
> >>> > >
> >>> > > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
> >>> > > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
> >>> > > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
> >>> > > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
> >>> > > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
> >>> > > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
> >>> > > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> >>> > > |[  255.822602] Mem abort info:
> >>> > > |[  255.822604]   ESR = 0x0000000096000044
> >>> > > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
> >>> > > |[  255.822613]   SET = 0, FnV = 0
> >>> > > |[  255.822616]   EA = 0, S1PTW = 0
> >>> > > |[  255.822618]   FSC = 0x04: level 0 translation fault
> >>> > > |[  255.822622] Data abort info:
> >>> > > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
> >>> > > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
> >>> > > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> >>> > > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
> >>> > > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
> >>> > > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
> >>> > > |[  255.822655] Modules linked in:
> >>> > > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
> >>> > > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
> >>> > > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> >>> > > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
> >>> > > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
> >>> > > |[  255.822696] sp : ffff800085ec3bc0
> >>> > > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
> >>> > > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
> >>> > > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
> >>> > > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
> >>> > > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
> >>> > > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
> >>> > > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
> >>> > > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
> >>> > > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
> >>> > > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
> >>> > > |[  255.822764] Call trace:
> >>> > > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
> >>>
> >>> Shouldn't xsk_tx_metadata_complete() be called only when corresponding
> >>> buf_type is STMMAC_TXBUF_T_XSK_TX?
> >>
> >> +1. I'm assuming Serge isn't enabling it explicitly, so none of the
> >> metadata stuff should trigger in this case.
> >
> > The only other user of xsk_tx_metadata_complete() in mlx5 guards it with
> > xp_tx_metadata_enabled(). Seems like that's missing in stmmac?
> 
> Well, the following patch seems to help:
> 
> commit e85ab4b97b4d6e50036435ac9851b876c221f580
> Author: Kurt Kanzenbach <kurt@linutronix.de>
> Date:   Wed Feb 21 08:18:15 2024 +0100
> 
>     net: stmmac: Complete meta data only when enabled
>     
>     Currently using XDP sockets on stmmac results in a kernel crash:
>     
>     |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
>     |[...]
>     |[  255.822764] Call trace:
>     |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
>     
>     The program counter indicates xsk_tx_metadata_complete(). However, this
>     function shouldn't be called unless metadata is actually enabled.
>     
>     Tested on imx93.
>     
>     Fixes: 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC")
>     Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 9df27f03a8cb..77c62b26342d 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -2678,9 +2678,10 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue,
>                                         .desc = p,
>                                 };
>  
> -                               xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
> -                                                        &stmmac_xsk_tx_metadata_ops,
> -                                                        &tx_compl);
> +                               if (xp_tx_metadata_enabled(tx_q->xsk_pool))

every other usage of tx metadata functions should be wrapped with
xp_tx_metadata_enabled() - can you address other places and send a proper
patch?

> +                                       xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
> +                                                                &stmmac_xsk_tx_metadata_ops,
> +                                                                &tx_compl);
>                         }
>                 }



^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-21 15:59           ` Maciej Fijalkowski
@ 2024-02-21 17:20             ` Serge Semin
  2024-02-22  8:35               ` Kurt Kanzenbach
  0 siblings, 1 reply; 10+ messages in thread
From: Serge Semin @ 2024-02-21 17:20 UTC (permalink / raw)
  To: Maciej Fijalkowski, Kurt Kanzenbach
  Cc: Stanislav Fomichev, netdev, Sebastian Andrzej Siewior,
	Song Yoong Siang, Alexei Starovoitov

[-- Attachment #1: Type: text/plain, Size: 7987 bytes --]

On Wed, Feb 21, 2024 at 04:59:10PM +0100, Maciej Fijalkowski wrote:
> On Wed, Feb 21, 2024 at 10:21:04AM +0100, Kurt Kanzenbach wrote:
> > On Wed Feb 21 2024, Kurt Kanzenbach wrote:
> > > On Tue Feb 20 2024, Stanislav Fomichev wrote:
> > >> On Tue, Feb 20, 2024 at 6:43 AM Maciej Fijalkowski
> > >> <maciej.fijalkowski@intel.com> wrote:
> > >>>
> > >>> On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
> > >>> > Hi Kurt
> > >>> >
> > >>> > On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
> > >>> > > Hello netdev community,
> > >>> > >
> > >>> > > after updating to v6.8 kernel I've encountered an issue in the stmmac
> > >>> > > driver.
> > >>> > >
> > >>> > > I have an application which makes use of XDP zero-copy sockets. It works
> > >>> > > on v6.7. On v6.8 it results in the stack trace shown below. The program
> > >>> > > counter points to:
> > >>> > >
> > >>> > >  - ./include/net/xdp_sock.h:192 and
> > >>> > >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
> > >>> > >
> > >>> > > It seems to be caused by the XDP meta data patches. This one in
> > >>> > > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
> > >>> > >
> > >>> > > To reproduce:
> > >>> > >
> > >>> > >  - Hardware: imx93
> > >>> > >  - Run ptp4l/phc2sys
> > >>> > >  - Configure Qbv, Rx steering, NAPI threading
> > >>> > >  - Run my application using XDP/ZC on queue 1
> > >>> > >
> > >>> > > Any idea what might be the issue here?
> > >>> > >
> > >>> > > Thanks,
> > >>> > > Kurt
> > >>> > >
> > >>> > > Stack trace:
> > >>> > >
> > >>> > > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
> > >>> > > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
> > >>> > > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
> > >>> > > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
> > >>> > > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
> > >>> > > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
> > >>> > > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> > >>> > > |[  255.822602] Mem abort info:
> > >>> > > |[  255.822604]   ESR = 0x0000000096000044
> > >>> > > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
> > >>> > > |[  255.822613]   SET = 0, FnV = 0
> > >>> > > |[  255.822616]   EA = 0, S1PTW = 0
> > >>> > > |[  255.822618]   FSC = 0x04: level 0 translation fault
> > >>> > > |[  255.822622] Data abort info:
> > >>> > > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
> > >>> > > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
> > >>> > > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> > >>> > > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
> > >>> > > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
> > >>> > > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
> > >>> > > |[  255.822655] Modules linked in:
> > >>> > > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
> > >>> > > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
> > >>> > > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> > >>> > > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
> > >>> > > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
> > >>> > > |[  255.822696] sp : ffff800085ec3bc0
> > >>> > > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
> > >>> > > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
> > >>> > > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
> > >>> > > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
> > >>> > > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
> > >>> > > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
> > >>> > > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
> > >>> > > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
> > >>> > > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
> > >>> > > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
> > >>> > > |[  255.822764] Call trace:
> > >>> > > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
> > >>>
> > >>> Shouldn't xsk_tx_metadata_complete() be called only when corresponding
> > >>> buf_type is STMMAC_TXBUF_T_XSK_TX?
> > >>
> > >> +1. I'm assuming Serge isn't enabling it explicitly, so none of the
> > >> metadata stuff should trigger in this case.
> > >
> > > The only other user of xsk_tx_metadata_complete() in mlx5 guards it with
> > > xp_tx_metadata_enabled(). Seems like that's missing in stmmac?
> > 
> > Well, the following patch seems to help:
> > 
> > commit e85ab4b97b4d6e50036435ac9851b876c221f580
> > Author: Kurt Kanzenbach <kurt@linutronix.de>
> > Date:   Wed Feb 21 08:18:15 2024 +0100
> > 
> >     net: stmmac: Complete meta data only when enabled
> >     
> >     Currently using XDP sockets on stmmac results in a kernel crash:
> >     
> >     |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> >     |[...]
> >     |[  255.822764] Call trace:
> >     |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
> >     
> >     The program counter indicates xsk_tx_metadata_complete(). However, this
> >     function shouldn't be called unless metadata is actually enabled.
> >     
> >     Tested on imx93.
> >     
> >     Fixes: 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC")
> >     Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
> > 
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > index 9df27f03a8cb..77c62b26342d 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> > @@ -2678,9 +2678,10 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue,
> >                                         .desc = p,
> >                                 };
> >  
> > -                               xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
> > -                                                        &stmmac_xsk_tx_metadata_ops,
> > -                                                        &tx_compl);
> > +                               if (xp_tx_metadata_enabled(tx_q->xsk_pool))
> 

> every other usage of tx metadata functions should be wrapped with
> xp_tx_metadata_enabled() - can you address other places and send a proper
> patch?

AFAICS this is the only place. But the change above still isn't enough
to fix the problem. In my case XDP zero-copy isn't activated. So
xsk_pool isn't allocated and the NULL/~NULL dereference is still
persistent due to xp_tx_metadata_enabled() dereferencing the
NULL-structure fields. The attached patched fixes the problem in my
case.

Kurt, are you sure that xp_tx_metadata_enabled() is required in your
case? Could you test the attached patch with the
xp_tx_metadata_enabled() invocation discarded?

Maciej, do we need xp_tx_metadata_enabled() guarding the
xsk_tx_metadata_complete() call even if the problem is fixed without
it?

-Serge(y)

> 
> > +                                       xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
> > +                                                                &stmmac_xsk_tx_metadata_ops,
> > +                                                                &tx_compl);
> >                         }
> >                 }
> 
> 

[-- Attachment #2: 0001-net-stmmac-Complete-meta-data-only-when-enabled.patch --]
[-- Type: text/x-patch, Size: 1539 bytes --]

From fffab4a5d012875ff6e842901e5bb7db00d9d0ed Mon Sep 17 00:00:00 2001
From: Kurt Kanzenbach <kurt@linutronix.de>
Date: Wed, 21 Feb 2024 17:24:25 +0300
Subject: [PATCH] net: stmmac: Complete meta data only when enabled

Currently using XDP sockets on stmmac results in a kernel crash:

|[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
|[...]
|[  255.822764] Call trace:
|[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38

The program counter indicates xsk_tx_metadata_complete(). However, this
function shouldn't be called unless metadata is actually enabled.

Tested on imx93.

Fixes: 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC")
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 8000fa256dfc..f6c86478a820 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -2634,7 +2634,8 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue,
 			}
 			if (skb) {
 				stmmac_get_tx_hwtstamp(priv, p, skb);
-			} else {
+			} else if (tx_q->xsk_pool &&
+				   xp_tx_metadata_enabled(tx_q->xsk_pool)) {
 				struct stmmac_xsk_tx_complete tx_compl = {
 					.priv = priv,
 					.desc = p,
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-21 17:20             ` Serge Semin
@ 2024-02-22  8:35               ` Kurt Kanzenbach
  2024-02-22 10:06                 ` Serge Semin
  0 siblings, 1 reply; 10+ messages in thread
From: Kurt Kanzenbach @ 2024-02-22  8:35 UTC (permalink / raw)
  To: Serge Semin, Maciej Fijalkowski
  Cc: Stanislav Fomichev, netdev, Sebastian Andrzej Siewior,
	Song Yoong Siang, Alexei Starovoitov

[-- Attachment #1: Type: text/plain, Size: 8363 bytes --]

On Wed Feb 21 2024, Serge Semin wrote:
> On Wed, Feb 21, 2024 at 04:59:10PM +0100, Maciej Fijalkowski wrote:
>> On Wed, Feb 21, 2024 at 10:21:04AM +0100, Kurt Kanzenbach wrote:
>> > On Wed Feb 21 2024, Kurt Kanzenbach wrote:
>> > > On Tue Feb 20 2024, Stanislav Fomichev wrote:
>> > >> On Tue, Feb 20, 2024 at 6:43 AM Maciej Fijalkowski
>> > >> <maciej.fijalkowski@intel.com> wrote:
>> > >>>
>> > >>> On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
>> > >>> > Hi Kurt
>> > >>> >
>> > >>> > On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
>> > >>> > > Hello netdev community,
>> > >>> > >
>> > >>> > > after updating to v6.8 kernel I've encountered an issue in the stmmac
>> > >>> > > driver.
>> > >>> > >
>> > >>> > > I have an application which makes use of XDP zero-copy sockets. It works
>> > >>> > > on v6.7. On v6.8 it results in the stack trace shown below. The program
>> > >>> > > counter points to:
>> > >>> > >
>> > >>> > >  - ./include/net/xdp_sock.h:192 and
>> > >>> > >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
>> > >>> > >
>> > >>> > > It seems to be caused by the XDP meta data patches. This one in
>> > >>> > > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
>> > >>> > >
>> > >>> > > To reproduce:
>> > >>> > >
>> > >>> > >  - Hardware: imx93
>> > >>> > >  - Run ptp4l/phc2sys
>> > >>> > >  - Configure Qbv, Rx steering, NAPI threading
>> > >>> > >  - Run my application using XDP/ZC on queue 1
>> > >>> > >
>> > >>> > > Any idea what might be the issue here?
>> > >>> > >
>> > >>> > > Thanks,
>> > >>> > > Kurt
>> > >>> > >
>> > >>> > > Stack trace:
>> > >>> > >
>> > >>> > > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
>> > >>> > > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
>> > >>> > > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
>> > >>> > > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
>> > >>> > > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
>> > >>> > > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
>> > >>> > > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
>> > >>> > > |[  255.822602] Mem abort info:
>> > >>> > > |[  255.822604]   ESR = 0x0000000096000044
>> > >>> > > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
>> > >>> > > |[  255.822613]   SET = 0, FnV = 0
>> > >>> > > |[  255.822616]   EA = 0, S1PTW = 0
>> > >>> > > |[  255.822618]   FSC = 0x04: level 0 translation fault
>> > >>> > > |[  255.822622] Data abort info:
>> > >>> > > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
>> > >>> > > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
>> > >>> > > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
>> > >>> > > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
>> > >>> > > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
>> > >>> > > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
>> > >>> > > |[  255.822655] Modules linked in:
>> > >>> > > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
>> > >>> > > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
>> > >>> > > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
>> > >>> > > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
>> > >>> > > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
>> > >>> > > |[  255.822696] sp : ffff800085ec3bc0
>> > >>> > > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
>> > >>> > > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
>> > >>> > > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
>> > >>> > > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
>> > >>> > > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
>> > >>> > > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
>> > >>> > > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
>> > >>> > > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
>> > >>> > > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
>> > >>> > > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
>> > >>> > > |[  255.822764] Call trace:
>> > >>> > > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
>> > >>>
>> > >>> Shouldn't xsk_tx_metadata_complete() be called only when corresponding
>> > >>> buf_type is STMMAC_TXBUF_T_XSK_TX?
>> > >>
>> > >> +1. I'm assuming Serge isn't enabling it explicitly, so none of the
>> > >> metadata stuff should trigger in this case.
>> > >
>> > > The only other user of xsk_tx_metadata_complete() in mlx5 guards it with
>> > > xp_tx_metadata_enabled(). Seems like that's missing in stmmac?
>> > 
>> > Well, the following patch seems to help:
>> > 
>> > commit e85ab4b97b4d6e50036435ac9851b876c221f580
>> > Author: Kurt Kanzenbach <kurt@linutronix.de>
>> > Date:   Wed Feb 21 08:18:15 2024 +0100
>> > 
>> >     net: stmmac: Complete meta data only when enabled
>> >     
>> >     Currently using XDP sockets on stmmac results in a kernel crash:
>> >     
>> >     |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
>> >     |[...]
>> >     |[  255.822764] Call trace:
>> >     |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
>> >     
>> >     The program counter indicates xsk_tx_metadata_complete(). However, this
>> >     function shouldn't be called unless metadata is actually enabled.
>> >     
>> >     Tested on imx93.
>> >     
>> >     Fixes: 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC")
>> >     Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
>> > 
>> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> > index 9df27f03a8cb..77c62b26342d 100644
>> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
>> > @@ -2678,9 +2678,10 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue,
>> >                                         .desc = p,
>> >                                 };
>> >  
>> > -                               xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
>> > -                                                        &stmmac_xsk_tx_metadata_ops,
>> > -                                                        &tx_compl);
>> > +                               if (xp_tx_metadata_enabled(tx_q->xsk_pool))
>> 
>
>> every other usage of tx metadata functions should be wrapped with
>> xp_tx_metadata_enabled() - can you address other places and send a proper
>> patch?
>
> AFAICS this is the only place. But the change above still isn't enough
> to fix the problem. In my case XDP zero-copy isn't activated. So
> xsk_pool isn't allocated and the NULL/~NULL dereference is still
> persistent due to xp_tx_metadata_enabled() dereferencing the
> NULL-structure fields. The attached patched fixes the problem in my
> case.

Sure about that? In my case without ZC the else path is not executed,
because skb is set.

>
> Kurt, are you sure that xp_tx_metadata_enabled() is required in your
> case?

Yes, I'm sure it's required, because I do use ZC without using any
metadata.

> Could you test the attached patch with the xp_tx_metadata_enabled()
> invocation discarded?

Well, it works. But, the xp_tx_metadata_enabled() is not discarded in
the ZC case:

|RtcRxThread-790     [001] b...3   202.970243: stmmac_tx_clean.constprop.0: huhu from xp_tx_metadata_enabled

Let's go with your version of the patch. It works without XDP, with XDP
and XDP/ZC. I'll send it upstream.

Thanks for the help :).

Thanks,
Kurt

[-- Attachment #2: signature.asc --]
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^ permalink raw reply	[flat|nested] 10+ messages in thread

* Re: stmmac and XDP/ZC issue
  2024-02-22  8:35               ` Kurt Kanzenbach
@ 2024-02-22 10:06                 ` Serge Semin
  0 siblings, 0 replies; 10+ messages in thread
From: Serge Semin @ 2024-02-22 10:06 UTC (permalink / raw)
  To: Kurt Kanzenbach
  Cc: Maciej Fijalkowski, Stanislav Fomichev, netdev,
	Sebastian Andrzej Siewior, Song Yoong Siang, Alexei Starovoitov

On Thu, Feb 22, 2024 at 09:35:02AM +0100, Kurt Kanzenbach wrote:
> On Wed Feb 21 2024, Serge Semin wrote:
> > On Wed, Feb 21, 2024 at 04:59:10PM +0100, Maciej Fijalkowski wrote:
> >> On Wed, Feb 21, 2024 at 10:21:04AM +0100, Kurt Kanzenbach wrote:
> >> > On Wed Feb 21 2024, Kurt Kanzenbach wrote:
> >> > > On Tue Feb 20 2024, Stanislav Fomichev wrote:
> >> > >> On Tue, Feb 20, 2024 at 6:43 AM Maciej Fijalkowski
> >> > >> <maciej.fijalkowski@intel.com> wrote:
> >> > >>>
> >> > >>> On Tue, Feb 20, 2024 at 04:18:54PM +0300, Serge Semin wrote:
> >> > >>> > Hi Kurt
> >> > >>> >
> >> > >>> > On Tue, Feb 20, 2024 at 12:02:25PM +0100, Kurt Kanzenbach wrote:
> >> > >>> > > Hello netdev community,
> >> > >>> > >
> >> > >>> > > after updating to v6.8 kernel I've encountered an issue in the stmmac
> >> > >>> > > driver.
> >> > >>> > >
> >> > >>> > > I have an application which makes use of XDP zero-copy sockets. It works
> >> > >>> > > on v6.7. On v6.8 it results in the stack trace shown below. The program
> >> > >>> > > counter points to:
> >> > >>> > >
> >> > >>> > >  - ./include/net/xdp_sock.h:192 and
> >> > >>> > >  - ./drivers/net/ethernet/stmicro/stmmac/stmmac_main.c:2681
> >> > >>> > >
> >> > >>> > > It seems to be caused by the XDP meta data patches. This one in
> >> > >>> > > particular 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC").
> >> > >>> > >
> >> > >>> > > To reproduce:
> >> > >>> > >
> >> > >>> > >  - Hardware: imx93
> >> > >>> > >  - Run ptp4l/phc2sys
> >> > >>> > >  - Configure Qbv, Rx steering, NAPI threading
> >> > >>> > >  - Run my application using XDP/ZC on queue 1
> >> > >>> > >
> >> > >>> > > Any idea what might be the issue here?
> >> > >>> > >
> >> > >>> > > Thanks,
> >> > >>> > > Kurt
> >> > >>> > >
> >> > >>> > > Stack trace:
> >> > >>> > >
> >> > >>> > > |[  169.248150] imx-dwmac 428a0000.ethernet eth1: configured EST
> >> > >>> > > |[  191.820913] imx-dwmac 428a0000.ethernet eth1: EST: SWOL has been switched
> >> > >>> > > |[  226.039166] imx-dwmac 428a0000.ethernet eth1: entered promiscuous mode
> >> > >>> > > |[  226.203262] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-0
> >> > >>> > > |[  226.203753] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_PAGE_POOL RxQ-1
> >> > >>> > > |[  226.303337] imx-dwmac 428a0000.ethernet eth1: Register MEM_TYPE_XSK_BUFF_POOL RxQ-1
> >> > >>> > > |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> >> > >>> > > |[  255.822602] Mem abort info:
> >> > >>> > > |[  255.822604]   ESR = 0x0000000096000044
> >> > >>> > > |[  255.822608]   EC = 0x25: DABT (current EL), IL = 32 bits
> >> > >>> > > |[  255.822613]   SET = 0, FnV = 0
> >> > >>> > > |[  255.822616]   EA = 0, S1PTW = 0
> >> > >>> > > |[  255.822618]   FSC = 0x04: level 0 translation fault
> >> > >>> > > |[  255.822622] Data abort info:
> >> > >>> > > |[  255.822624]   ISV = 0, ISS = 0x00000044, ISS2 = 0x00000000
> >> > >>> > > |[  255.822627]   CM = 0, WnR = 1, TnD = 0, TagAccess = 0
> >> > >>> > > |[  255.822630]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
> >> > >>> > > |[  255.822634] user pgtable: 4k pages, 48-bit VAs, pgdp=0000000085fe1000
> >> > >>> > > |[  255.822638] [0000000000000000] pgd=0000000000000000, p4d=0000000000000000
> >> > >>> > > |[  255.822650] Internal error: Oops: 0000000096000044 [#1] PREEMPT_RT SMP
> >> > >>> > > |[  255.822655] Modules linked in:
> >> > >>> > > |[  255.822660] CPU: 0 PID: 751 Comm: napi/eth1-261 Not tainted 6.8.0-rc4-rt4-00100-g9c63d995ca19 #8
> >> > >>> > > |[  255.822666] Hardware name: NXP i.MX93 11X11 EVK board (DT)
> >> > >>> > > |[  255.822669] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
> >> > >>> > > |[  255.822674] pc : stmmac_tx_clean.constprop.0+0x848/0xc38
> >> > >>> > > |[  255.822690] lr : stmmac_tx_clean.constprop.0+0x844/0xc38
> >> > >>> > > |[  255.822696] sp : ffff800085ec3bc0
> >> > >>> > > |[  255.822698] x29: ffff800085ec3bc0 x28: ffff000005b609e0 x27: 0000000000000001
> >> > >>> > > |[  255.822706] x26: 0000000000000000 x25: ffff000005b60ae0 x24: 0000000000000001
> >> > >>> > > |[  255.822712] x23: 0000000000000001 x22: ffff000005b649e0 x21: 0000000000000000
> >> > >>> > > |[  255.822719] x20: 0000000000000020 x19: ffff800085291030 x18: 0000000000000000
> >> > >>> > > |[  255.822725] x17: ffff7ffffc51c000 x16: ffff800080000000 x15: 0000000000000008
> >> > >>> > > |[  255.822732] x14: ffff80008369b880 x13: 0000000000000000 x12: 0000000000008507
> >> > >>> > > |[  255.822738] x11: 0000000000000040 x10: 0000000000000a70 x9 : ffff800080e32f84
> >> > >>> > > |[  255.822745] x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000003ff0
> >> > >>> > > |[  255.822751] x5 : 0000000000003c40 x4 : ffff000005b60000 x3 : 0000000000000000
> >> > >>> > > |[  255.822757] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000000
> >> > >>> > > |[  255.822764] Call trace:
> >> > >>> > > |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
> >> > >>>
> >> > >>> Shouldn't xsk_tx_metadata_complete() be called only when corresponding
> >> > >>> buf_type is STMMAC_TXBUF_T_XSK_TX?
> >> > >>
> >> > >> +1. I'm assuming Serge isn't enabling it explicitly, so none of the
> >> > >> metadata stuff should trigger in this case.
> >> > >
> >> > > The only other user of xsk_tx_metadata_complete() in mlx5 guards it with
> >> > > xp_tx_metadata_enabled(). Seems like that's missing in stmmac?
> >> > 
> >> > Well, the following patch seems to help:
> >> > 
> >> > commit e85ab4b97b4d6e50036435ac9851b876c221f580
> >> > Author: Kurt Kanzenbach <kurt@linutronix.de>
> >> > Date:   Wed Feb 21 08:18:15 2024 +0100
> >> > 
> >> >     net: stmmac: Complete meta data only when enabled
> >> >     
> >> >     Currently using XDP sockets on stmmac results in a kernel crash:
> >> >     
> >> >     |[  255.822584] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000
> >> >     |[...]
> >> >     |[  255.822764] Call trace:
> >> >     |[  255.822766]  stmmac_tx_clean.constprop.0+0x848/0xc38
> >> >     
> >> >     The program counter indicates xsk_tx_metadata_complete(). However, this
> >> >     function shouldn't be called unless metadata is actually enabled.
> >> >     
> >> >     Tested on imx93.
> >> >     
> >> >     Fixes: 1347b419318d ("net: stmmac: Add Tx HWTS support to XDP ZC")
> >> >     Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
> >> > 
> >> > diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> >> > index 9df27f03a8cb..77c62b26342d 100644
> >> > --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> >> > +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> >> > @@ -2678,9 +2678,10 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue,
> >> >                                         .desc = p,
> >> >                                 };
> >> >  
> >> > -                               xsk_tx_metadata_complete(&tx_q->tx_skbuff_dma[entry].xsk_meta,
> >> > -                                                        &stmmac_xsk_tx_metadata_ops,
> >> > -                                                        &tx_compl);
> >> > +                               if (xp_tx_metadata_enabled(tx_q->xsk_pool))
> >> 
> >
> >> every other usage of tx metadata functions should be wrapped with
> >> xp_tx_metadata_enabled() - can you address other places and send a proper
> >> patch?
> >
> > AFAICS this is the only place. But the change above still isn't enough
> > to fix the problem. In my case XDP zero-copy isn't activated. So
> > xsk_pool isn't allocated and the NULL/~NULL dereference is still
> > persistent due to xp_tx_metadata_enabled() dereferencing the
> > NULL-structure fields. The attached patched fixes the problem in my
> > case.
> 
> Sure about that? In my case without ZC the else path is not executed,
> because skb is set.

Absolutely. Don't know why you haven't got the NULL-dereference bug as
I have. I was able to track the bug up to not having the
stmmac_rx_queue::xsk_pool allocated. Maybe your case is different in a
aspect that the pool had been pre-allocated someway before the ZC was
disabled. Anyway I agree it will be safer to keep the xsk_pool pointer
sanity check as it's done in the rest of the places in the driver.

> 
> >
> > Kurt, are you sure that xp_tx_metadata_enabled() is required in your
> > case?
> 
> Yes, I'm sure it's required, because I do use ZC without using any
> metadata.

Ok.

> 
> > Could you test the attached patch with the xp_tx_metadata_enabled()
> > invocation discarded?
> 
> Well, it works. But, the xp_tx_metadata_enabled() is not discarded in
> the ZC case:
> 
> |RtcRxThread-790     [001] b...3   202.970243: stmmac_tx_clean.constprop.0: huhu from xp_tx_metadata_enabled
> 
> Let's go with your version of the patch. It works without XDP, with XDP
> and XDP/ZC. I'll send it upstream.
> 
> Thanks for the help :).

Thanks for posting the patch. Here is the link for the lore archive:
https://lore.kernel.org/netdev/20240222-stmmac_xdp-v1-1-e8d2d2b79ff0@linutronix.de

-Serge(y)

> 
> Thanks,
> Kurt



^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2024-02-22 10:06 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-02-20 11:02 stmmac and XDP/ZC issue Kurt Kanzenbach
2024-02-20 13:18 ` Serge Semin
2024-02-20 14:43   ` Maciej Fijalkowski
2024-02-20 21:57     ` Stanislav Fomichev
2024-02-21  7:13       ` Kurt Kanzenbach
2024-02-21  9:21         ` Kurt Kanzenbach
2024-02-21 15:59           ` Maciej Fijalkowski
2024-02-21 17:20             ` Serge Semin
2024-02-22  8:35               ` Kurt Kanzenbach
2024-02-22 10:06                 ` Serge Semin

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