bisecting fixing commit since ae83d0b416db002fe95601e7f97f64b59514d936
building syzkaller on 347a5dc3c7886bfe3ce784eabc5ee30100f13e0a
testing commit ae83d0b416db002fe95601e7f97f64b59514d936 with gcc (GCC) 8.1.0
kernel signature: d9410648f6f6d50cda2e9c4c8a57e0d37db60a0db71287613b87e6bd0123c59d
all runs: crashed: WARNING in kcm_write_msgs
testing current HEAD 3d5e28bff7ad55aea081c1af516cc1c94a5eca7d
testing commit 3d5e28bff7ad55aea081c1af516cc1c94a5eca7d with gcc (GCC) 8.1.0
kernel signature: 4049506cd6bd9ba9a7fc6b5aa9c9cb759b855c5e2f5100e181e1b283e8b6dbe1
all runs: crashed: WARNING in kcm_write_msgs
revisions tested: 2, total time: 17m26.104042166s (build: 10m59.13177063s, test: 5m47.965785117s)
the crash still happens on HEAD
commit msg: Merge branch 'stable/for-linus-5.10-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
crash: WARNING in kcm_write_msgs
------------[ cut here ]------------
WARNING: CPU: 1 PID: 8472 at net/kcm/kcmsock.c:628 kcm_write_msgs+0x481/0x570 net/kcm/kcmsock.c:661
Modules linked in:
CPU: 1 PID: 8472 Comm: syz-executor.1 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kcm_write_msgs+0x481/0x570 net/kcm/kcmsock.c:628
Code: 24 1c 00 00 00 00 e9 4c fe ff ff 48 8b 74 24 30 31 d2 0f b7 44 24 10 44 89 3e 44 89 56 08 89 46 04 4c 89 66 10 e9 ae fc ff ff <0f> 0b ba ea ff ff ff e9 a2 fc ff ff 0f 0b e9 44 fd ff ff 44 89 7c
RSP: 0018:ffffc90000efbcc8 EFLAGS: 00010246
RAX: 00000000000000c0 RBX: ffff8881220d1200 RCX: 0000000000000000
RDX: 0000000000008000 RSI: ffff8881220d12c0 RDI: 0000000000000000
RBP: ffff8881233ccb40 R08: 0000000000000001 R09: ffff88810a507d00
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8881010958c0 R14: ffff88810e215700 R15: 0000000000198000
FS:  00007ff26cff3700(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055daff494970 CR3: 00000001223c2000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 kcm_sendmsg+0x799/0x7e0 net/kcm/kcmsock.c:1034
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0x2b/0x40 net/socket.c:671
 sock_write_iter+0x95/0xf0 net/socket.c:998
 call_write_iter include/linux/fs.h:1887 [inline]
 new_sync_write+0x18e/0x1a0 fs/read_write.c:518
 vfs_write+0x195/0x230 fs/read_write.c:605
 ksys_write+0xb9/0xd0 fs/read_write.c:658
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c8a9
Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ff26cff2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000509ec0 RCX: 000000000045c8a9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000c4e R14: 00000000004ca108 R15: 00007ff26cff36d4