On 9/14/22 10:40, Jay Vosburgh wrote:
Jonathan Toppins <jtoppins@xxxxxxxxxx> wrote:
This bonding selftest causes the following kernel oops on aarch64 and
possibly ppc64le architectures. This was reproduced on net/master commit
64ae13ed478428135cddc2f1113dff162d8112d4 net: core: fix flow symmetric hash
[ 329.805838] kselftest: Running tests in drivers/net/bonding
[ 330.011028] eth0: renamed from link1_2
[ 330.220846] eth0: renamed from link1_1
[ 330.387755] bond0: (slave eth0): making interface the new active one
[ 330.394165] bond0: (slave eth0): Enslaving as an active interface with an up link
[ 330.401867] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[ 334.586619] bond0: (slave eth0): Releasing backup interface
[ 334.671065] bond0: (slave eth0): Enslaving as an active interface with an up link
[ 334.686773] Unable to handle kernel paging request at virtual address ffff2c91ac905000
[ 334.694703] Mem abort info:
[ 334.697486] ESR = 0x0000000096000004
[ 334.701234] EC = 0x25: DABT (current EL), IL = 32 bits
[ 334.706536] SET = 0, FnV = 0
[ 334.709579] EA = 0, S1PTW = 0
[ 334.712719] FSC = 0x04: level 0 translation fault
[ 334.717586] Data abort info:
[ 334.720454] ISV = 0, ISS = 0x00000004
[ 334.724288] CM = 0, WnR = 0
[ 334.727244] swapper pgtable: 4k pages, 48-bit VAs, pgdp=000008044d662000
[ 334.733944] [ffff2c91ac905000] pgd=0000000000000000, p4d=0000000000000000
[ 334.740734] Internal error: Oops: 96000004 [#1] SMP
[ 334.745602] Modules linked in: bonding tls veth rfkill sunrpc arm_spe_pmu vfat fat acpi_ipmi ipmi_ssif ixgbe igb i40e mdio ipmi_devintf ipmi_msghandler arm_cmn arm_dsu_pmu cppc_cpufreq acpi_tad fuse zram crct10dif_ce ast ghash_ce sbsa_gwdt nvme drm_vram_helper drm_ttm_helper nvme_core ttm xgene_hwmon
[ 334.772217] CPU: 7 PID: 2214 Comm: ping Not tainted 6.0.0-rc4-00133-g64ae13ed4784 #4
[ 334.779950] Hardware name: GIGABYTE R272-P31-00/MP32-AR1-00, BIOS F18v (SCP: 1.08.20211002) 12/01/2021
[ 334.789244] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 334.796196] pc : bond_rr_gen_slave_id+0x40/0x124 [bonding]
[ 334.801691] lr : bond_xmit_roundrobin_slave_get+0x38/0xdc [bonding]
What line in the source code is that? Looking at the function,
I don't really see anything that's arch specific, unless perhaps the
rr_tx_counter assignment isn't visible for some ARM cache reason (i.e.,
the dcache on the relevant cpu already had a populated cache line that's
out of date, and wasn't flushed).
$ printf "%#x\n" $((0x$(nm drivers/net/bonding/bonding.ko | grep
bond_rr_gen_slave_id | awk '{print $1}') + 0x40))
0x47d0
$ eu-addr2line -e drivers/net/bonding/bonding.ko 0x47d0
/home/jtoppins/projects/linux/./arch/arm64/include/asm/percpu.h:130:1
It appears to be a percpu arch specific issue. The cache line idea is a
thought, not sure how to go about debugging on arm. I also have a report
with a similar stack trace on ppc64le, but do not have a box to test on
at this moment. I mention this as maybe someone else might see a generic
non arch specific issue.
I could not reproduce the issue on x86_64 using a Fedora 36 kernel and
this same test-case, I have not tested this specific upstream hash on
x86_64. That was the plan for today.
[ 334.807962] sp : ffff8000221733e0
[ 334.811265] x29: ffff8000221733e0 x28: ffffdbac8572d198 x27: ffff80002217357c
[ 334.818392] x26: 000000000000002a x25: ffffdbacb33ee000 x24: ffff07ff980fa000
[ 334.825519] x23: ffffdbacb2e398ba x22: ffff07ff98102000 x21: ffff07ff981029c0
[ 334.832646] x20: 0000000000000001 x19: ffff07ff981029c0 x18: 0000000000000014
[ 334.839773] x17: 0000000000000000 x16: ffffdbacb1004364 x15: 0000aaaabe2f5a62
[ 334.846899] x14: ffff07ff8e55d968 x13: ffff07ff8e55db30 x12: 0000000000000000
[ 334.854026] x11: ffffdbacb21532e8 x10: 0000000000000001 x9 : ffffdbac857178ec
[ 334.861153] x8 : ffff07ff9f6e5a28 x7 : 0000000000000000 x6 : 000000007c2b3742
[ 334.868279] x5 : ffff2c91ac905000 x4 : ffff2c91ac905000 x3 : ffff07ff9f554400
[ 334.875406] x2 : ffff2c91ac905000 x1 : 0000000000000001 x0 : ffff07ff981029c0
[ 334.882532] Call trace:
[ 334.884967] bond_rr_gen_slave_id+0x40/0x124 [bonding]
[ 334.890109] bond_xmit_roundrobin_slave_get+0x38/0xdc [bonding]
[ 334.896033] __bond_start_xmit+0x128/0x3a0 [bonding]
[ 334.901001] bond_start_xmit+0x54/0xb0 [bonding]
[ 334.905622] dev_hard_start_xmit+0xb4/0x220
[ 334.909798] __dev_queue_xmit+0x1a0/0x720
[ 334.913799] arp_xmit+0x3c/0xbc
[ 334.916932] arp_send_dst+0x98/0xd0
[ 334.920410] arp_solicit+0xe8/0x230
[ 334.923888] neigh_probe+0x60/0xb0
[ 334.927279] __neigh_event_send+0x3b0/0x470
[ 334.931453] neigh_resolve_output+0x70/0x90
[ 334.935626] ip_finish_output2+0x158/0x514
[ 334.939714] __ip_finish_output+0xac/0x1a4
[ 334.943800] ip_finish_output+0x40/0xfc
[ 334.947626] ip_output+0xf8/0x1a4
[ 334.950931] ip_send_skb+0x5c/0x100
[ 334.954410] ip_push_pending_frames+0x3c/0x60
[ 334.958758] raw_sendmsg+0x458/0x6d0
[ 334.962325] inet_sendmsg+0x50/0x80
[ 334.965805] sock_sendmsg+0x60/0x6c
[ 334.969286] __sys_sendto+0xc8/0x134
[ 334.972853] __arm64_sys_sendto+0x34/0x4c
[ 334.976854] invoke_syscall+0x78/0x100
[ 334.980594] el0_svc_common.constprop.0+0x4c/0xf4
[ 334.985287] do_el0_svc+0x38/0x4c
[ 334.988591] el0_svc+0x34/0x10c
[ 334.991724] el0t_64_sync_handler+0x11c/0x150
[ 334.996072] el0t_64_sync+0x190/0x194
[ 334.999726] Code: b9001062 f9403c02 d53cd044 8b040042 (b8210040)
[ 335.005810] ---[ end trace 0000000000000000 ]---
[ 335.010416] Kernel panic - not syncing: Oops: Fatal exception in interrupt
[ 335.017279] SMP: stopping secondary CPUs
[ 335.021374] Kernel Offset: 0x5baca8eb0000 from 0xffff800008000000
[ 335.027456] PHYS_OFFSET: 0x80000000
[ 335.030932] CPU features: 0x0000,0085c029,19805c82
[ 335.035713] Memory Limit: none
[ 335.038756] Rebooting in 180 seconds..
Signed-off-by: Jonathan Toppins <jtoppins@xxxxxxxxxx>
---
.../selftests/drivers/net/bonding/Makefile | 1 +
.../bonding/bond-arp-interval-causes-panic.sh | 46 +++++++++++++++++++
2 files changed, 47 insertions(+)
create mode 100755 tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh
diff --git a/tools/testing/selftests/drivers/net/bonding/Makefile b/tools/testing/selftests/drivers/net/bonding/Makefile
index ab6c54b12098..79bb06fd386a 100644
--- a/tools/testing/selftests/drivers/net/bonding/Makefile
+++ b/tools/testing/selftests/drivers/net/bonding/Makefile
@@ -2,5 +2,6 @@
# Makefile for net selftests
TEST_PROGS := bond-break-lacpdu-tx.sh
+TEST_PROGS += bond-arp-interval-causes-panic.sh
include ../../../lib.mk
diff --git a/tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh b/tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh
new file mode 100755
index 000000000000..0c3e5d486193
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/bonding/bond-arp-interval-causes-panic.sh
@@ -0,0 +1,46 @@
+#!/bin/sh
+
+# cause kernel oops in bond_rr_gen_slave_id on aarch64 and ppcle
+# architectures
+DEBUG=${DEBUG:-0}
+
+set -e
+test ${DEBUG} -ne 0 && set -x
+
+function finish()
+{
+ ip -all netns delete
+ ip link del link1_1 || true
+}
+
+trap finish EXIT
+
+client_ip4=192.168.1.198
+server_ip4=192.168.1.254
+
+# setup kernel so it reboots after causing the panic
+echo 180 >/proc/sys/kernel/panic
+
+# build namespaces
+ip link add dev link1_1 type veth peer name link1_2
+
+ip netns add "server"
+ip link set dev link1_2 netns server up name eth0
+ip netns exec server ip addr add ${server_ip4}/24 dev eth0
+
+ip netns add "client"
+ip link set dev link1_1 netns client down name eth0
+ip netns exec client ip link add dev bond0 down type bond mode 1 miimon 100 all_slaves_active 1
+ip netns exec client ip link set dev eth0 down master bond0
+ip netns exec client ip link set dev bond0 up
+ip netns exec client ip addr add ${client_ip4}/24 dev bond0
+ip netns exec client ping -c 5 $server_ip4 >/dev/null
+
+ip netns exec client ip link set dev eth0 down nomaster
+ip netns exec client ip link set dev bond0 down
+ip netns exec client ip link set dev bond0 type bond mode 0 arp_interval 1000 arp_ip_target "+${server_ip4}"
+ip netns exec client ip link set dev eth0 down master bond0
+ip netns exec client ip link set dev bond0 up
+ip netns exec client ping -c 5 $server_ip4 >/dev/null
+
+exit 0
--
2.31.1