219648 – Losetup Direct I/O breaks BACK-FILE filesystem on CIFS share (Appears in Linux 6.10 and reproduced on mainline)

Bug 219648 - Losetup Direct I/O breaks BACK-FILE filesystem on CIFS share (Appears in Linux 6.10 and reproduced on mainline)

Summary: Losetup Direct I/O breaks BACK-FILE filesystem on CIFS share (Appears in Linu...

Status:	RESOLVED CODE_FIX

Alias:	None

Product:	File System
Classification:	Unclassified
Component:	Other (show other bugs)
Hardware:	All Linux

Importance:	P3 blocking
Assignee:	fs_other

URL:
Keywords:

Depends on:
Blocks:

Reported:	2025-01-01 10:34 UTC by Nicolas BARANGER
Modified:	2025-01-20 16:02 UTC (History)
CC List:	2 users (show)

See Also:
Kernel Version:	from Linux 6.10 to mainline
Subsystem:
Regression:	Yes
Bisected commit-id:	not before kernel 6.9.12 but present from kernel 6.10 to mainline

Attachments
Add an attachment (proposed patch, testcase, etc.)

Description Nicolas BARANGER 2025-01-01 10:34:45 UTC

Dear maintener,

Since I upgrade 1 server from Linux 6.9.12 to Linux 6.10, I encountered the following problem : 

Backups of one server are made by writing a dd copy of each LVM volumes snapshots into a BACK FILE (LUKS + BTRFS formated) which reside on a big SAMBA share (SMB 3.1.1).

The BACK FILE is mounted on the server using 'losetup --sector-size 4096 --direct-io=on /dev/loop2046 /path/to/back-file/on/samba/share'

It has work very fine since years and years and this methode is it still working on the same share ( and different back-files ) from other servers using respectively Linux 6.1.25 and Linux 6.5.10 and Linux 6.9.12

But since I update kernel to Linux  6.10, when I mount the BACK-FILE, at the first write the BACK-FILE becomes read-only  and I have this error in kernel logs :

[lun. 23 déc. 10:08:49 2024] loop2046: detected capacity change from 0 to 8589934592
[lun. 23 déc. 10:08:51 2024] BTRFS: device fsid a2c979e6-2c6e-4308-a238-55e417a3bcd9 devid 1 transid 395 /dev/mapper/bckcrypt (253:30) scanned by mount (3643571)
[lun. 23 déc. 10:08:51 2024] BTRFS info (device dm-30): first mount of filesystem a2c979e6-2c6e-4308-a238-55e417a3bcd9
[lun. 23 déc. 10:08:51 2024] BTRFS info (device dm-30): using crc32c (crc32c-intel) checksum algorithm
[lun. 23 déc. 10:08:51 2024] BTRFS info (device dm-30): disk space caching is enabled
[lun. 23 déc. 10:08:51 2024] BTRFS warning (device dm-30): space cache v1 is being deprecated and will be removed in a future release, please use -o space_cache=v2
[lun. 23 déc. 10:08:51 2024] BTRFS info (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 15, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:08:54 2024] blk_print_req_error: 62 callbacks suppressed
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014676032 op 0x1:(WRITE) flags 0x8800 phys_seg 6 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014675776 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014688456 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014688968 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014689224 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014689736 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014688200 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014689480 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014688712 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] I/O error, dev loop2046, sector 7014690248 op 0x1:(WRITE) flags 0x8800 phys_seg 2 prio class 0
[lun. 23 déc. 10:08:54 2024] btrfs_dev_stat_inc_and_print: 54 callbacks suppressed
[lun. 23 déc. 10:08:54 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 16, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:08:54 2024] BTRFS warning (device dm-30): direct IO failed ino 361 op 0x8801 offset 0x611000 len 2138112 err no 10
[lun. 23 déc. 10:08:54 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 17, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:08:54 2024] BTRFS warning (device dm-30): direct IO failed ino 361 op 0x8801 offset 0x81b000 len 2129920 err no 10
[lun. 23 déc. 10:08:54 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 18, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:08:54 2024] BTRFS warning (device dm-30): direct IO failed ino 361 op 0x8801 offset 0xa23000 len 2088960 err no 10
[lun. 23 déc. 10:08:54 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 19, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:08:54 2024] BTRFS warning (device dm-30): direct IO failed ino 361 op 0x8801 offset 0x0 len 4190208 err no 10
[lun. 23 déc. 10:08:54 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 20, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:08:54 2024] BTRFS warning (device dm-30): direct IO failed ino 361 op 0x8801 offset 0x3ff000 len 2170880 err no 10
[lun. 23 déc. 10:09:24 2024] blk_print_req_error: 82 callbacks suppressed
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 183168 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 182912 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 21, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 180864 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 181120 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 22, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 181120 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 180864 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 23, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 180864 op 0x1:(WRITE) flags 0x800 phys_seg 4 prio class 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 185216 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 24, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 184960 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 25, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:24 2024] I/O error, dev loop2046, sector 183680 op 0x1:(WRITE) flags 0x800 phys_seg 2 prio class 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 26, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 27, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:24 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 28, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:25 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 29, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:25 2024] BTRFS error (device dm-30): bdev /dev/mapper/bckcrypt errs: wr 30, rd 15, flush 0, corrupt 0, gen 0
[lun. 23 déc. 10:09:25 2024] BTRFS: error (device dm-30) in btrfs_commit_transaction:2524: errno=-5 IO failure (Error while writing out transaction)
[lun. 23 déc. 10:09:25 2024] BTRFS info (device dm-30 state E): forced readonly
[lun. 23 déc. 10:09:25 2024] BTRFS warning (device dm-30 state E): Skipping commit of aborted transaction.
[lun. 23 déc. 10:09:25 2024] BTRFS error (device dm-30 state EA): Transaction aborted (error -5)
[lun. 23 déc. 10:09:25 2024] BTRFS: error (device dm-30 state EA) in cleanup_transaction:2018: errno=-5 IO failure


So First I thought that BTRFS and the fifteen READ / WRITE errors "bdev /dev/mapper/bckcrypt errs: wr 15, rd 15" was responsible of the issue, so I recreate 100% of the back file on the CIFS share the following way : 

dd if=/dev/urandom of=/mnt/FBX24T/bck0crypt2044 bs=1G count=4096 oflag=direct status=progress
losetup --sector-size 4096 --direct-io=on loop2044 /mnt/FBX24T/bck0crypt2044
cryptsetup luksFormat /dev/loop2044 

and normally after (but it didn't work here as the back-file becomes read-only)
cryptsetup open /dev/loop2044 bck0crypt2044
mkfs.btrfs /dev/mapper/bck0crypt2044
mount  /dev/mapper/bck0crypt2044 /mnt/bck0crypt

But I cannot do the last part, it breaks at the first write of 'cryptsetup luksFormat /dev/loop2044'

When testing to directly format the loop device with BTRFS and XFS and EXT4, I get the same failiure, ie: at the first write IO the loop device become read-only with the provided errors.

So I decide to test again, removing --direct-io=on from losetup command and I was able to format with cryptsetup and btrfs (I also tried xfs and ext4, all with same result: broken with --direct-io=on and working without, same after mounting the loop device whatever filesystem it contains)  

So this is the  '--direct-io=on' which breaks (from Linux 6.10 to mainline) when the back-file is on a CIFS share.
To validate, I did try  '--direct-io=on' on a local filesystem with no issue (same process with cryptsetup and brtfs or xfs or ext4)

And to be sure, I did umount the read-only device from the server and remove the losetup device too and I go to my Debian 12 laptop with kernel 6.9.12 and I mount the CIFS share on which the 'broken' back-file reside, creating a loop device (with  '--direct-io=on' ) and I open it with cryptsetup and mount it (as previously described).
After that I did issue about 1TB of write from my laptop to this loop device with no issues.

One of the biggest problem here removing the '--direct-io=on' from losetup command is the read/write performance of the loop device: about 150Mib/s without '--direct-io=on' (which make it unusable for backuping a server every day) and more than 3Gib/s with '--direct-io=on' option.
So with  '--direct-io=on' , the write speed is between 25 to 50 times the speed I constat without the option (making this solution viable for an 'every day' full backup of 2TB+)

When having a deeper look in the kernel logs, I find that the issue is always precede by the following 'netfs:' error: 

[mer.  1 janv. 10:58:53 2025] ------------[ cut here ]------------
[mer.  1 janv. 10:58:53 2025] WARNING: CPU: 2 PID: 109 at fs/netfs/iterator.c:50 netfs_extract_user_iter+0x170/0x250 [netfs]
[mer.  1 janv. 10:58:53 2025] Modules linked in: dm_crypt(E) cmac(E) nls_utf8(E) cifs(E) cifs_arc4(E) nls_ucs2_utils(E) cifs_md4(E) dns_resolver(E) netfs(E) snd_seq_dummy(E) snd_hrtimer(E) snd_seq(E) snd_seq_device(E) rfkill(E) qrtr(E) binfmt_misc(E) nls_ascii(E) nls_cp437(E) vfat(E) fat(E) ext4(E) crc16(E) mbcache(E) jbd2(E) intel_rapl_msr(E) intel_rapl_common(E) intel_uncore_frequency_common(E) kvm_intel(E) kvm(E) ghash_clmulni_intel(E) sha512_ssse3(E) sha256_ssse3(E) sha1_ssse3(E) snd_intel8x0(E) snd_ac97_codec(E) ac97_bus(E) aesni_intel(E) crypto_simd(E) cryptd(E) snd_pcm(E) joydev(E) rapl(E) snd_timer(E) snd(E) vboxguest(OE) pcspkr(E) soundcore(E) ac(E) sg(E) serio_raw(E) evdev(E) msr(E) parport_pc(E) ppdev(E) lp(E) parport(E) loop(E) configfs(E) efi_pstore(E) efivarfs(E) ip_tables(E) x_tables(E) autofs4(E) btrfs(E) blake2b_generic(E) xor(E) raid6_pq(E) libcrc32c(E) crc32c_generic(E) dm_mod(E) hid_generic(E) usbhid(E) hid(E) nvme(E) sr_mod(E) cdrom(E) nvme_core(E) t10_pi(E) vmwgfx(E) ahci(E) xhci_pci(E) drm_ttm_helper(E)
[mer.  1 janv. 10:58:53 2025]  virtio_net(E) ttm(E) libahci(E) net_failover(E) crc64_rocksoft(E) crc32_pclmul(E) drm_kms_helper(E) xhci_hcd(E) failover(E) crc64(E) libata(E) crc32c_intel(E) psmouse(E) crc_t10dif(E) dimlib(E) crct10dif_generic(E) crct10dif_pclmul(E) crct10dif_common(E) scsi_mod(E) usbcore(E) drm(E) scsi_common(E) usb_common(E) i2c_piix4(E) video(E) wmi(E) button(E)
[mer.  1 janv. 10:58:53 2025] CPU: 2 PID: 109 Comm: kworker/u35:1 Tainted: G        W  OE      6.10.0-amd64 #1
[mer.  1 janv. 10:58:53 2025] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[mer.  1 janv. 10:58:53 2025] Workqueue: loop2046 loop_rootcg_workfn [loop]
[mer.  1 janv. 10:58:53 2025] RIP: 0010:netfs_extract_user_iter+0x170/0x250 [netfs]
[mer.  1 janv. 10:58:53 2025] Code: 00 29 fb 31 ff 89 5a f8 4c 39 d9 75 c2 4d 85 c9 0f 84 c2 00 00 00 45 39 f2 0f 83 b9 00 00 00 4d 89 cd 44 89 d3 e9 35 ff ff ff <0f> 0b 48 c7 c3 fb ff ff ff 48 8b 44 24 28 65 48 2b 04 25 28 00 00
[mer.  1 janv. 10:58:53 2025] RSP: 0018:ffffa44f00887c10 EFLAGS: 00010202
[mer.  1 janv. 10:58:53 2025] RAX: 0000000000000000 RBX: ffff937da084b200 RCX: 0000000000000000
[mer.  1 janv. 10:58:53 2025] RDX: ffff937da084b340 RSI: 0000000000100000 RDI: ffffa44f00887d10
[mer.  1 janv. 10:58:53 2025] RBP: ffff937da0837920 R08: ffffffffc13f7bc0 R09: 0000000000000000
[mer.  1 janv. 10:58:53 2025] R10: ffff937da084b200 R11: ffff937b81149100 R12: 0000000000100000
[mer.  1 janv. 10:58:53 2025] R13: ffffa44f00887d10 R14: ffffffffc0dbbeb0 R15: 0000034702500000
[mer.  1 janv. 10:58:53 2025] FS:  0000000000000000(0000) GS:ffff937e8fb00000(0000) knlGS:0000000000000000
[mer.  1 janv. 10:58:53 2025] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[mer.  1 janv. 10:58:53 2025] CR2: 00007efe292cb9f0 CR3: 00000001c53f4001 CR4: 00000000000706f0
[mer.  1 janv. 10:58:53 2025] Call Trace:
[mer.  1 janv. 10:58:53 2025]  <TASK>
[mer.  1 janv. 10:58:53 2025]  ? __warn+0x80/0x120
[mer.  1 janv. 10:58:53 2025]  ? netfs_extract_user_iter+0x170/0x250 [netfs]
[mer.  1 janv. 10:58:53 2025]  ? report_bug+0x164/0x190
[mer.  1 janv. 10:58:53 2025]  ? handle_bug+0x41/0x70
[mer.  1 janv. 10:58:53 2025]  ? exc_invalid_op+0x17/0x70
[mer.  1 janv. 10:58:53 2025]  ? asm_exc_invalid_op+0x1a/0x20
[mer.  1 janv. 10:58:53 2025]  ? __pfx_lo_rw_aio_complete+0x10/0x10 [loop]
[mer.  1 janv. 10:58:53 2025]  ? netfs_extract_user_iter+0x170/0x250 [netfs]
[mer.  1 janv. 10:58:53 2025]  ? __pfx_lo_rw_aio_complete+0x10/0x10 [loop]
[mer.  1 janv. 10:58:53 2025]  netfs_unbuffered_write_iter_locked+0x97/0x3a0 [netfs]
[mer.  1 janv. 10:58:53 2025]  netfs_unbuffered_write_iter+0x177/0x230 [netfs]
[mer.  1 janv. 10:58:53 2025]  lo_rw_aio.isra.0+0x2ad/0x2d0 [loop]
[mer.  1 janv. 10:58:53 2025]  loop_process_work+0xae/0x980 [loop]
[mer.  1 janv. 10:58:53 2025]  ? psi_task_switch+0xd6/0x230
[mer.  1 janv. 10:58:53 2025]  ? _raw_spin_unlock+0xe/0x30
[mer.  1 janv. 10:58:53 2025]  ? finish_task_switch.isra.0+0x88/0x2d0
[mer.  1 janv. 10:58:53 2025]  ? __schedule+0x3f3/0xb40
[mer.  1 janv. 10:58:53 2025]  process_one_work+0x17c/0x390
[mer.  1 janv. 10:58:53 2025]  worker_thread+0x265/0x380
[mer.  1 janv. 10:58:53 2025]  ? __pfx_worker_thread+0x10/0x10
[mer.  1 janv. 10:58:53 2025]  kthread+0xd2/0x100
[mer.  1 janv. 10:58:53 2025]  ? __pfx_kthread+0x10/0x10
[mer.  1 janv. 10:58:53 2025]  ret_from_fork+0x34/0x50
[mer.  1 janv. 10:58:53 2025]  ? __pfx_kthread+0x10/0x10
[mer.  1 janv. 10:58:53 2025]  ret_from_fork_asm+0x1a/0x30
[mer.  1 janv. 10:58:53 2025]  </TASK>
[mer.  1 janv. 10:58:53 2025] ---[ end trace 0000000000000000 ]---
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038117888 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038187520 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038185472 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038183424 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038181376 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038179328 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038177280 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038175232 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038173184 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] I/O error, dev loop2046, sector 7038171136 op 0x1:(WRITE) flags 0x8800 phys_seg 16 prio class 0
[mer.  1 janv. 10:58:53 2025] BTRFS error (device dm-7): bdev /dev/mapper/bckcrypt errs: wr 16, rd 15, flush 0, corrupt 0, gen 0
[mer.  1 janv. 10:58:53 2025] BTRFS warning (device dm-7): direct IO failed ino 360 op 0x8801 offset 0x0 len 268435456 err no 10


NB: I'm able to reproduce it everytime on Virtual Machines + on physical hardware (server, laptop, pc ...) and while trying to bissect the regression, I build and test nearly all kernels from Linux 6.9.6 to mainline with the exact same result: still working from Linux 6.9.6 to 6.9.12 and failing from Linux 6.10(.0) to mainline

I'm not a kernel developer but I stay availiable for help or to reproduce and give traces of this issue (having now some VM in my lab dedicated to build new kernel + to tests and reproduce this particular issue, and if needed a public IPv6 access to those lab machines could be privately share with the maintener and a live demo of the issue can be organised).


Thanks for help
Kind regards
Nicolas Baranger

Comment 1 David Disseldorp 2025-01-03 10:40:04 UTC

Thanks for the report. Can you provide your cifs.ko mount options?

It looks as though the netfs is module throwing I/O errors, which results in the higher level device / Btrfs error messages:

 36 ssize_t netfs_extract_user_iter(struct iov_iter *orig, size_t orig_len,
 37                                 struct iov_iter *new,
 38                                 iov_iter_extraction_t extraction_flags)
 39 {
 40         struct bio_vec *bv = NULL;
 41         struct page **pages;
 42         unsigned int cur_npages;
 43         unsigned int max_pages;
 44         unsigned int npages = 0;
 45         unsigned int i;
 46         ssize_t ret;
 47         size_t count = orig_len, offset, len;
 48         size_t bv_size, pg_size;
 49 
 50         if (WARN_ON_ONCE(!iter_is_ubuf(orig) && !iter_is_iovec(orig)))
 51                 return -EIO;
                           ^^^^---- here

Comment 2 Nicolas BARANGER 2025-01-03 11:09:34 UTC

Hi 

Here are information you asked : 

$ lsmod | grep cifs
cifs                 1474560  2
cifs_arc4              12288  1 cifs
nls_ucs2_utils          8192  1 cifs
cifs_md4               12288  1 cifs
dns_resolver           12288  1 cifs
netfs                 569344  1 cifs

$ grep cifs /proc/mounts 
//10.0.10.100/FBX24T /mnt/FBX24T cifs rw,nosuid,nodev,noexec,relatime,vers=3.1.1,cache=none,username=fbx,domain=HOMELAN,uid=0,noforceuid,gid=0,noforcegid,addr=10.0.10.100,file_mode=0666,dir_mode=0755,iocharset=utf8,soft,nounix,serverino,mapposix,mfsymlinks,reparse=nfs,rsize=65536,wsize=65536,bsize=16777216,retrans=1,echo_interval=60,actimeo=1,closetimeo=1 0 0


Don't you think the new way CIFS makes its IO in Linux 6.10 through NETFS could be part of the issue ?

$ git log --pretty=oneline v6.9.12..v6.10 | grep cifs: | grep netfs
3ee1a1fc39819906f04d6c62c180e760cd3a689d cifs: Cut over to using netfslib
69c3c023af25edb5433a2db824d3e7cc328f0183 cifs: Implement netfslib hooks
dc5939de82f149633d6ec1c403003538442ec9ef cifs: Replace the writedata replay bool with a netfs sreq flag
ab58fbdeebc7f9fe8b9bc202660eae3a10e5e678 cifs: Use more fields from netfs_io_subrequest
a975a2f22cdce7ec0c678ce8d73d2f6616cb281c cifs: Replace cifs_writedata with a wrapper around netfs_io_subrequest
753b67eb630db34e36ec4ae1e86c75e243ea4fc9 cifs: Replace cifs_readdata with a wrapper around netfs_io_subrequest

Thanks again for help
Kind regards
Nicolas Baranger

Comment 3 Nicolas BARANGER 2025-01-20 16:02:53 UTC

Hi

This regression had been fixed and patch had been merged to mainline (Linux 6.13-rc7).

You can follow the story here:
https://lore.kernel.org/all/14271ed82a5be7fcc5ceea5f68a10bbd@manguebit.com/T/

I'm switching this issue status to "RESOLVED"

Again thanks everyone for help
Nicolas Baranger

Note You need to log in before you can comment on or make changes to this bug.