On Fri, Apr 9, 2021 at 2:41 PM Paweł Wiejacha <pawel.wiejacha@xxxxxxxxxxxx> wrote: > > Hello, > > Two of my machines constantly crash with a double fault like this: > > 1146 <0>[33685.629591] traps: PANIC: double fault, error_code: 0x0 > 1147 <4>[33685.629593] double fault: 0000 [#1] SMP NOPTI > 1148 <4>[33685.629594] CPU: 10 PID: 2118287 Comm: kworker/10:0 > Tainted: P OE 5.11.8-051108-generic #202103200636 > 1149 <4>[33685.629595] Hardware name: ASUSTeK COMPUTER INC. KRPG-U8 > Series/KRPG-U8 Series, BIOS 4201 09/25/2020 > 1150 <4>[33685.629595] Workqueue: xfs-conv/md12 xfs_end_io [xfs] > 1151 <4>[33685.629596] RIP: 0010:__slab_free+0x23/0x340 > 1152 <4>[33685.629597] Code: 4c fe ff ff 0f 1f 00 0f 1f 44 00 00 55 > 48 89 e5 41 57 49 89 cf 41 56 49 89 fe 41 55 41 54 49 89 f4 53 48 83 > e4 f0 48 83 ec 70 <48> 89 54 24 28 0f 1f 44 00 00 41 8b 46 28 4d 8b 6c > 24 20 49 8b 5c > 1153 <4>[33685.629598] RSP: 0018:ffffa9bc00848fa0 EFLAGS: 00010086 > 1154 <4>[33685.629599] RAX: ffff94c04d8b10a0 RBX: ffff94437a34a880 > RCX: ffff94437a34a880 > 1155 <4>[33685.629599] RDX: ffff94437a34a880 RSI: ffffcec745e8d280 > RDI: ffff944300043b00 > 1156 <4>[33685.629599] RBP: ffffa9bc00849040 R08: 0000000000000001 > R09: ffffffff82a5d6de > 1157 <4>[33685.629600] R10: 0000000000000001 R11: 000000009c109000 > R12: ffffcec745e8d280 > 1158 <4>[33685.629600] R13: ffff944300043b00 R14: ffff944300043b00 > R15: ffff94437a34a880 > 1159 <4>[33685.629601] FS: 0000000000000000(0000) > GS:ffff94c04d880000(0000) knlGS:0000000000000000 > 1160 <4>[33685.629601] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > 1161 <4>[33685.629602] CR2: ffffa9bc00848f98 CR3: 000000014d04e000 > CR4: 0000000000350ee0 > 1162 <4>[33685.629602] Call Trace: > 1163 <4>[33685.629603] <IRQ> > 1164 <4>[33685.629603] ? kfree+0x3bc/0x3e0 > 1165 <4>[33685.629603] ? mempool_kfree+0xe/0x10 > 1166 <4>[33685.629603] ? mempool_kfree+0xe/0x10 > 1167 <4>[33685.629604] ? mempool_free+0x2f/0x80 > 1168 <4>[33685.629604] ? md_end_io+0x4a/0x70 > 1169 <4>[33685.629604] ? bio_endio+0xdc/0x130 > 1170 <4>[33685.629605] ? bio_chain_endio+0x2d/0x40 > 1171 <4>[33685.629605] ? md_end_io+0x5c/0x70 > 1172 <4>[33685.629605] ? bio_endio+0xdc/0x130 > 1173 <4>[33685.629605] ? bio_chain_endio+0x2d/0x40 > 1174 <4>[33685.629606] ? md_end_io+0x5c/0x70 > 1175 <4>[33685.629606] ? bio_endio+0xdc/0x130 > 1176 <4>[33685.629606] ? bio_chain_endio+0x2d/0x40 > 1177 <4>[33685.629607] ? md_end_io+0x5c/0x70 > ... repeated ... > 1436 <4>[33685.629677] ? bio_endio+0xdc/0x130 > 1437 <4>[33685.629677] ? bio_chain_endio+0x2d/0x40 > 1438 <4>[33685.629677] ? md_end_io+0x5c/0x70 > 1439 <4>[33685.629677] ? bio_endio+0xdc/0x130 > 1440 <4>[33685.629678] ? bio_chain_endio+0x2d/0x40 > 1441 <4>[33685.629678] ? md_ > 1442 <4>[33685.629679] Lost 357 message(s)! > > This happens on: > 5.11.8-051108-generic #202103200636 SMP Sat Mar 20 11:17:32 UTC 2021 > and on 5.8.0-44-generic #50~20.04.1-Ubuntu > (https://changelogs.ubuntu.com/changelogs/pool/main/l/linux/linux_5.8.0-44.50/changelog) > which contains backported > https://github.com/torvalds/linux/commit/41d2d848e5c09209bdb57ff9c0ca34075e22783d > ("md: improve io stats accounting"). > The 5.8.18-050818-generic #202011011237 SMP Sun Nov 1 12:40:15 UTC > 2020 which does not contain above suspected change does not crash. > > If there's a better way/place to report this bug just let me know. If > not, here are steps to reproduce: > > 1. Create a RAID 0 device using three Micron_9300_MTFDHAL7T6TDP disks. > mdadm --create --verbose /dev/md12 --level=stripe --raid-devices=3 > /dev/nvme0n1p1 /dev/nvme1n1p1 /dev/nvme2n1p1 > > 2. Setup xfs on it: > mkfs.xfs /dev/md12 and mount it > > 3. Write to a file on this filesystem: > while true; do rm -rf /mnt/md12/crash* ; for i in `seq 8`; do dd > if=/dev/zero of=/mnt/md12/crash$i bs=32K count=50000000 & done; wait; > done > Wait for a crash (usually less than 20 min). > > I couldn't reproduce it with a single dd process (maybe I have to wait > a little longer), but a single cat > /very/large/file/on/cephfs/over100GbE > /mnt/md12/crash is enough for > this double fault to occur. > > More info: > This long mempool_kfree - md_end_io - * -md_end_io stack trace looks > always the same, but the panic occurs in different places: > > pstore/6948115143318/dmesg.txt-<4>[545649.087998] CPU: 88 PID: 0 Comm: > swapper/88 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6948377398316/dmesg.txt-<4>[11275.914909] CPU: 14 PID: 0 Comm: > swapper/14 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6948532816002/dmesg.txt-<4>[33685.629594] CPU: 10 PID: 2118287 > Comm: kworker/10:0 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6948532816002/dmesg.txt-<4>[33685.629595] Workqueue: > xfs-conv/md12 xfs_end_io [xfs] > pstore/6948855849083/dmesg.txt-<4>[42934.321129] CPU: 85 PID: 0 Comm: > swapper/85 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6948876331782/dmesg.txt-<4>[ 3475.020672] CPU: 86 PID: 0 Comm: > swapper/86 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6949083860307/dmesg.txt-<4>[43048.254375] CPU: 45 PID: 0 Comm: > swapper/45 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6949091775931/dmesg.txt-<4>[ 1150.790240] CPU: 64 PID: 0 Comm: > swapper/64 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6949123356826/dmesg.txt-<4>[ 6963.858253] CPU: 6 PID: 51 Comm: > kworker/6:0 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6949123356826/dmesg.txt-<4>[ 6963.858255] Workqueue: ceph-msgr > ceph_con_workfn [libceph] > pstore/6949123356826/dmesg.txt-<4>[ 6963.858253] CPU: 6 PID: 51 Comm: > kworker/6:0 Tainted: P OE 5.11.8-051108-generic > #202103200636 > pstore/6949123356826/dmesg.txt-<4>[ 6963.858255] Workqueue: ceph-msgr > ceph_con_workfn [libceph] > pstore/6949152322085/dmesg.txt-<4>[ 6437.077874] CPU: 59 PID: 0 Comm: > swapper/59 Tainted: P OE 5.11.8-051108-generic > #202103200636 > > cat /proc/cmdline > BOOT_IMAGE=/vmlinuz-5.11.8-051108-generic > root=/dev/mapper/ubuntu--vg-ubuntu--lv ro net.ifnames=0 biosdevname=0 > strict-devmem=0 mitigations=off iommu=pt > > cat /proc/cpuinfo > model name : AMD EPYC 7552 48-Core Processor > > cat /proc/mounts > /dev/md12 /mnt/ssd1 xfs > rw,noatime,attr2,inode64,logbufs=8,logbsize=32k,sunit=1024,swidth=3072,prjquota > 0 0 > > Let me know if you need more information. Hi Pawel, Thanks for the report. Could you please try whether the following change fixes the issue? Song diff --git i/drivers/md/md.c w/drivers/md/md.c index bb09070a63bcf..889e9440a9f38 100644 --- i/drivers/md/md.c +++ w/drivers/md/md.c @@ -5648,7 +5648,7 @@ static int md_alloc(dev_t dev, char *name) */ mddev->hold_active = UNTIL_STOP; - error = mempool_init_kmalloc_pool(&mddev->md_io_pool, BIO_POOL_SIZE, + error = mempool_init_slab_pool(&mddev->md_io_pool, BIO_POOL_SIZE, sizeof(struct md_io)); if (error) goto abort;
