On 21/03/2019 15:25, Jens Axboe wrote: > On 3/21/19 8:23 AM, Johannes Thumshirn wrote: >> On 21/03/2019 15:21, Jens Axboe wrote: >>> On 3/21/19 8:15 AM, Jens Axboe wrote: >>>> You also haven't solved the issue of now having an extra bit, 2/2 uses >>>> the last bit which the other patch already took... >>> >>> Here's one way - kill BIO_SEG_VALID. We should just use >>> ->bi_phys_segments to tell if it's valid or not. This patch uses -1 to >>> signify it's not. >>> >>> Totally untested... >> >> >> That sounds like an idea, I'll trow some testing at it and report back. > > That'd be great, thanks. If we can do that as a prep patch for you, then > you can just use an enum and not worry about initializing since I'll just > shove BIO_PAGE_NO_REF at the end. > > And this is simpler than having to shift the masks around. > OK it survived xfstests on BTRFS and XFS(on zram) but blktests block/002 runs into this: [ 7.730469] WARNING: CPU: 1 PID: 283 at drivers/scsi/scsi_lib.c:1018 scsi_init_io+0x132/0x160 [scsi_mod] [ 7.732062] Modules linked in: scsi_debug(E+) scsi_mod(E) zram(E) [ 7.733094] CPU: 1 PID: 283 Comm: modprobe Tainted: G E 5.1.0-rc1-default+ #943 [ 7.735046] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.0-0-g63451fc-prebuilt.qemu-project.org 04/01/2014 [ 7.737504] RIP: 0010:scsi_init_io+0x132/0x160 [scsi_mod] [ 7.738408] Code: 39 c5 7c 47 48 8b 55 00 0f b7 92 78 04 00 00 39 d0 7f 36 4c 89 a3 10 01 00 00 41 89 44 24 08 31 c0 5b 5d 41 5c 41 5d 41 5e c3 <0f> 0b b8 0a 00 00 00 eb 98 0f 0b b8 09 00 00 00 eb 8f 0f 0b 41 be [ 7.741442] RSP: 0018:ffffb35a402eb6d8 EFLAGS: 00010246 [ 7.742296] RAX: 0000000000000002 RBX: ffff8d805f4d0118 RCX: 0000000000000024 [ 7.743451] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8d805f4d0118 [ 7.744637] RBP: ffff8d805f4d0000 R08: 0000000000000000 R09: ffff8d805f4d0150 [ 7.745819] R10: 0000000000000024 R11: ffffb35a402eb7b8 R12: ffff8d805f4d0000 [ 7.746977] R13: ffff8d8052fbd000 R14: ffff8d805f4d0118 R15: ffff8d805fbe4c00 [ 7.748132] FS: 00007ffa8a26e700(0000) GS:ffff8d805cb00000(0000) knlGS:0000000000000000 [ 7.749438] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 7.750366] CR2: 00007ffa899c39b2 CR3: 00000000137d6000 CR4: 00000000000006e0 [ 7.751520] Call Trace: [ 7.751940] scsi_queue_rq+0x72a/0x9a0 [scsi_mod] [ 7.753358] blk_mq_dispatch_rq_list+0x80/0x4b0 [ 7.754100] ? dd_dispatch_request+0x21/0x220 [ 7.754815] blk_mq_do_dispatch_sched+0x64/0xd0 [ 7.755575] blk_mq_sched_dispatch_requests+0xe9/0x160 [ 7.756417] __blk_mq_run_hw_queue+0x5f/0xf0 [ 7.757108] __blk_mq_delay_run_hw_queue+0x106/0x150 [ 7.757913] blk_mq_run_hw_queue+0x51/0x100 [ 7.758595] blk_mq_sched_insert_request+0xa2/0x130 [ 7.759383] blk_execute_rq+0x3b/0x80 [ 7.759981] __scsi_execute+0xb5/0x1e0 [scsi_mod] [ 7.760754] scsi_probe_and_add_lun+0x270/0xd60 [scsi_mod] [ 7.761641] ? scsi_alloc_target+0x274/0x340 [scsi_mod] [ 7.762487] __scsi_scan_target+0xcc/0x220 [scsi_mod] [ 7.763307] scsi_scan_channel.part.14+0x52/0x70 [scsi_mod] [ 7.764210] scsi_scan_host_selected+0xe3/0x190 [scsi_mod] [ 7.765098] ? __pm_runtime_resume+0x48/0x60 [ 7.765807] scsi_scan_host+0x16a/0x1b0 [scsi_mod] [ 7.766580] sdebug_driver_probe+0x159/0x2c0 [scsi_debug] [ 7.767442] ? driver_sysfs_add+0x71/0xd0 [ 7.768101] ? driver_allows_async_probing+0x50/0x50 [ 7.768893] really_probe+0x229/0x420 [ 7.769492] ? driver_allows_async_probing+0x50/0x50 [ 7.770287] driver_probe_device+0x115/0x130 [ 7.770976] ? driver_allows_async_probing+0x50/0x50 [ 7.771770] bus_for_each_drv+0x54/0x80 [ 7.772398] __device_attach+0xb2/0x130 [ 7.773016] bus_probe_device+0x8a/0xa0 [ 7.773639] device_add+0x496/0x670 [ 7.774209] sdebug_add_adapter+0xf1/0x1b0 [scsi_debug] [ 7.775049] scsi_debug_init+0x6e3/0x1000 [scsi_debug] [ 7.775888] ? 0xffffffffc011a000 [ 7.776430] do_one_initcall+0x4e/0x1d4 [ 7.777048] do_init_module+0x5a/0x21d [ 7.777652] load_module+0x1926/0x1f00 [ 7.778255] ? m_show+0x1c0/0x1c0 [ 7.778794] __do_sys_finit_module+0x83/0xc0 [ 7.779482] do_syscall_64+0x5b/0x180 [ 7.780079] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 7.780882] RIP: 0033:0x7ffa89959969 [ 7.781459] Code: 00 f3 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ef 64 2b 00 f7 d8 64 89 01 48 [ 7.784402] RSP: 002b:00007ffca3d05938 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 7.785602] RAX: ffffffffffffffda RBX: 00000000010e6400 RCX: 00007ffa89959969 [ 7.786740] RDX: 0000000000000000 RSI: 000000000042ac19 RDI: 0000000000000004 [ 7.787858] RBP: 000000000042ac19 R08: 0000000000000000 R09: 00000000010e6310 [ 7.788985] R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000040000 [ 7.790107] R13: 0000000000000000 R14: 00000000010e6530 R15: 0000000000000000 1013 blk_status_t scsi_init_io(struct scsi_cmnd *cmd) 1014 { 1015 struct request *rq = cmd->request; 1016 blk_status_t ret; 1017 1018 if (WARN_ON_ONCE(!blk_rq_nr_phys_segments(rq))) 1019 return BLK_STS_IOERR; Looking into it now. -- Johannes Thumshirn SUSE Labs Filesystems jthumshirn@xxxxxxx +49 911 74053 689 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: Felix Imendörffer, Mary Higgins, Sri Rasiah HRB 21284 (AG Nürnberg) Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850