BUG: using __this_cpu_read() in preemptible [00000000] code: syz-executor6/13699 caller is __this_cpu_preempt_check+0x1c/0x20 lib/smp_processor_id.c:62 CPU: 0 PID: 13699 Comm: syz-executor6 Not tainted 4.9.78-g7be1985 #24 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801bb7b76d8 ffffffff81d94409 0000000000000000 ffffffff83c18800 ffffffff83f45480 ffff8801bf3e9800 0000000000000003 ffff8801bb7b7718 ffffffff81dfb9d4 ffff8801bb7b7730 ffffffff83f45480 dffffc0000000000 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] check_preemption_disabled+0x1d4/0x200 lib/smp_processor_id.c:46 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 13717 Comm: syz-executor0 Not tainted 4.9.78-g7be1985 #24 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff8801d82c6000 task.stack: ffff8801c44c8000 RIP: 0010:[] [] __read_once_size include/linux/compiler.h:243 [inline] RIP: 0010:[] [] atomic_read arch/x86/include/asm/atomic.h:26 [inline] RIP: 0010:[] [] page_ref_count include/linux/page_ref.h:66 [inline] RIP: 0010:[] [] put_page_testzero include/linux/mm.h:450 [inline] RIP: 0010:[] [] __free_pages+0x21/0x80 mm/page_alloc.c:3903 RSP: 0018:ffff8801c44cf9b0 EFLAGS: 00010a07 RAX: dffffc0000000000 RBX: dead4ead00000000 RCX: ffffffff8266775b RDX: 1bd5a9d5a0000003 RSI: 0000000000000001 RDI: dead4ead0000001c RBP: ffff8801c44cf9c0 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: ffff8801d82c6000 R12: 0000000000000004 R13: 0000000000000020 R14: ffff8801c4384200 R15: dffffc0000000000 FS: 00007f15e1e7e700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020dc8000 CR3: 00000001bd60e000 CR4: 0000000000160670 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Stack: ffffffff838b37a9 ffff8801c4384358 ffff8801c44cfa20 ffffffff82667781 ffff8801c4384370 ffffed003887086b ffffed003887086e ffff8801c4384368 dead4ead00000000 ffff8801c4384340 0000000000000000 0000000000000000 Call Trace: [] sg_remove_scat.isra.19+0x1c1/0x2d0 drivers/scsi/sg.c:1944 [] sg_finish_rem_req+0x2b5/0x340 drivers/scsi/sg.c:1825 [] sg_new_read.isra.20+0x356/0x3e0 drivers/scsi/sg.c:566 [] sg_read+0x8b7/0x1440 drivers/scsi/sg.c:455 [] do_loop_readv_writev.part.17+0x141/0x1e0 fs/read_write.c:714 [] do_loop_readv_writev fs/read_write.c:880 [inline] [] do_readv_writev+0x520/0x750 fs/read_write.c:874 [] vfs_readv+0x84/0xc0 fs/read_write.c:898 [] do_readv+0xe6/0x250 fs/read_write.c:924 [] SYSC_readv fs/read_write.c:1011 [inline] [] SyS_readv+0x27/0x30 fs/read_write.c:1008 [] entry_SYSCALL_64_fastpath+0x29/0xe8 Code: e9 27 fc ff ff 0f 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 53 48 89 fb 48 83 c7 1c 48 89 fa 48 83 ec 08 48 c1 ea 03 <0f> b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 3d RIP [] __read_once_size include/linux/compiler.h:243 [inline] RIP [] atomic_read arch/x86/include/asm/atomic.h:26 [inline] RIP [] page_ref_count include/linux/page_ref.h:66 [inline] RIP [] put_page_testzero include/linux/mm.h:450 [inline] RIP [] __free_pages+0x21/0x80 mm/page_alloc.c:3903 RSP ---[ end trace fdddf2228d87ae7d ]---