Re: rename ->make_request_fn and move it to the block_device_operations

Jens Axboe
2020-06-30T15:43:31Z

On 6/30/20 7:57 AM, Jens Axboe wrote:
> On 6/29/20 1:39 PM, Christoph Hellwig wrote:
>> Hi Jens,
>>
>> this series moves the make_request_fn method into block_device_operations
>> with the much more descriptive ->submit_bio name. It then also gives
>> generic_make_request a more descriptive name, and further optimize the
>> path to issue to blk-mq, removing the need for the direct_make_request
>> bypass.
>
> Looks good to me, and it's a nice cleanup as well. Applied.

Dropped, insta-crashes with dm:

[ 10.240134] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 10.241000] #PF: supervisor instruction fetch in kernel mode
[ 10.241666] #PF: error_code(0x0010) - not-present page
[ 10.242280] PGD 0 P4D 0
[ 10.242600] Oops: 0010 [#1] PREEMPT SMP
[ 10.243073] CPU: 1 PID: 2110 Comm: systemd-udevd Not tainted 5.8.0-rc3+ #6655
[ 10.243939] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1 04/01/2014
[ 10.245012] RIP: 0010:0x0
[ 10.245322] Code: Bad RIP value.
[ 10.245695] RSP: 0018:ffffc900002f7af8 EFLAGS: 00010246
[ 10.246333] RAX: ffffffff81c83520 RBX: ffff8881b805dea8 RCX: ffff88819e844070
[ 10.247227] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff88819e844070
[ 10.248112] RBP: ffffc900002f7b48 R08: ffff8881b6f38800 R09: ffff88818ff0ea58
[ 10.248994] R10: 0000000000000000 R11: ffff88818ff0ea58 R12: ffff88819e844070
[ 10.250077] R13: 00000000ffffffff R14: 0000000000000000 R15: ffff888107812948
[ 10.251168] FS: 00007f5c3ed66a80(0000) GS:ffff8881b9c80000(0000) knlGS:0000000000000000
[ 10.252161] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 10.253189] CR2: ffffffffffffffd6 CR3: 00000001b2953003 CR4: 00000000001606e0
[ 10.254157] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 10.255279] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 10.256365] Call Trace:
[ 10.256781] submit_bio_noacct+0x1f6/0x3d0
[ 10.257297] submit_bio+0x37/0x130
[ 10.257780] ? guard_bio_eod+0x2e/0x70
[ 10.258418] mpage_readahead+0x13c/0x180
[ 10.259096] ? blkdev_direct_IO+0x490/0x490
[ 10.259654] read_pages+0x68/0x2d0
[ 10.260051] page_cache_readahead_unbounded+0x1b7/0x220
[ 10.260818] generic_file_buffered_read+0x865/0xc80
[ 10.261587] ? _copy_to_user+0x6d/0x80
[ 10.262171] ? cp_new_stat+0x119/0x130
[ 10.262680] new_sync_read+0xfe/0x170
[ 10.263155] vfs_read+0xc8/0x180
[ 10.263647] ksys_read+0x53/0xc0
[ 10.264209] do_syscall_64+0x3c/0x70
[ 10.264759] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 10.265200] RIP: 0033:0x7f5c3fcc9ab2
[ 10.265510] Code: Bad RIP value.
[ 10.265775] RSP: 002b:00007ffc8e0cf9c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[ 10.266426] RAX: ffffffffffffffda RBX: 000055d5eca76c68 RCX: 00007f5c3fcc9ab2
[ 10.267012] RDX: 0000000000000040 RSI: 000055d5eca76c78 RDI: 0000000000000006
[ 10.267591] RBP: 000055d5eca44890 R08: 000055d5eca76c50 R09: 00007f5c3fd99a40
[ 10.268168] R10: 0000000000000008 R11: 0000000000000246 R12: 000000003bd90000
[ 10.268744] R13: 0000000000000040 R14: 000055d5eca76c50 R15: 000055d5eca448e0
[ 10.269319] Modules linked in:
[ 10.269562] CR2: 0000000000000000
[ 10.269845] ---[ end trace f09b8963e5a3593b ]---

--
Jens Axboe