syzbot


uvm_fault: savectx

Status: upstream: reported on 2022/11/25 10:19
Reported-by: syzbot+f512bb1e97d86ff17e36@syzkaller.appspotmail.com
First crash: 73d, last: 73d

Sample crash report:
uvm_fault(fffffd8066a202e0,20028000,0,1) at uvm_fault+0x238
end trace frame: 0xffff80002e497200, count: 0
ddb{0}> trace
x86_ipi_db(ffffffff8292eff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393
x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106
Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23
x86_bus_space_io_read_4(b008,0) at x86_bus_space_io_read_4+0x28 sys/arch/amd64/amd64/bus_space.c:663
acpitimer_delay(1) at acpitimer_delay+0x61 acpitimer_read sys/dev/acpi/acpitimer.c:143 [inline]
acpitimer_delay(1) at acpitimer_delay+0x61 sys/dev/acpi/acpitimer.c:121
comcnputc(800,7c) at comcnputc+0x1d7 sys/dev/ic/com.c:1269
cnputc(7c) at cnputc+0x4b sys/dev/cons.c:218
db_putchar(7c) at db_putchar+0x3fc sys/ddb/db_output.c:155
kprintf() at kprintf+0x20ec sys/kern/subr_prf.c:1064
db_printf(ffffffff82625b51) at db_printf+0x85 sys/kern/subr_prf.c:498
panic(ffffffff825ab8ec) at panic+0xd7 sys/kern/subr_prf.c:216
__assert(ffffffff8261fb71,ffffffff8259cbed,4dc,ffffffff825cbaa2) at __assert+0x25 sys/kern/subr_prf.c:157
uvm_fault_lower(ffff80002e4970c0,ffff80002e4970f8,ffff80002e497040,0) at uvm_fault_lower+0xb34 sys/uvm/uvm_fault.c:1245
uvm_fault(fffffd8066a202e0,20028000,0,1) at uvm_fault+0x238
kpageflttrap(ffff80002e497260,20028000) at kpageflttrap+0x22e sys/arch/amd64/amd64/trap.c:277
kerntrap(ffff80002e497260) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:332
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
copyin() at copyin+0x53
dofilewritev(ffff8000212fc2a0,4,ffff80002e497540,0,ffff80002e497630) at dofilewritev+0x397 sys/kern/sys_generic.c:396
sys_writev(ffff8000212fc2a0,ffff80002e4975e8,ffff80002e497630) at sys_writev+0xa7 sys/kern/sys_generic.c:322
syscall(ffff80002e4976b0) at syscall+0x4c2 mi_syscall sys/sys/syscall_mi.h:101 [inline]
syscall(ffff80002e4976b0) at syscall+0x4c2 sys/arch/amd64/amd64/trap.c:599
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xd5cc3892b20, count: -22
ddb{0}> machine ddbcpu 1
Stopped at      savectx+0xae:   movl    $0,%gs:0x540
savectx() at savectx+0xae
end of kernel
end trace frame: 0xd5d4107f6a0, count: 14
ddb{1}> trace
savectx() at savectx+0xae
end of kernel
end trace frame: 0xd5d4107f6a0, count: -1

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci-openbsd-multicore 2022/11/25 10:19 openbsd 2a4e68fdcb09 75740b3f .config console log report [disk image] [bsd.gdb] [kernel image] uvm_fault: savectx
* Struck through repros no longer work on HEAD.