Hi Li, On 1/11/19 3:08 AM, Li Qiang wrote: > When it is zero, it causes segv. Backtrack: > Thread 5 "qemu-system-x86" received signal SIGSEGV, Segmentation fault.
Can you add the relevant part of the command line you used here? > [Switching to Thread 0x7fffc6c17700 (LWP 51808)] > 0x0000555555acbd90 in nvme_start_ctrl (n=0x6240000c8100) at > hw/block/nvme.c:820 > warning: Source file is more recent than executable. ^ drop this line > 820 if (unlikely(n->cq[0])) { > (gdb) bt > 0 0x0000555555acbd90 in nvme_start_ctrl (n=0x6240000c8100) at > hw/block/nvme.c:820 > 1 0x0000555555accdbc in nvme_write_bar (n=0x6240000c8100, offset=20, > data=4587521, size=4) at hw/block/nvme.c:964 > 2 0x0000555555acdd2b in nvme_mmio_write (opaque=0x6240000c8100, addr=20, > data=4587521, size=4) at hw/block/nvme.c:1158 > 3 0x00005555558973ed in memory_region_write_accessor (mr=0x6240000c89e0, > addr=20, value=0x7fffc6c14428, size=4, shift=0, mask=4294967295, attrs=...) > at /home/liqiang02/qemu-upstream/qemu/memory.c:500 > 4 0x0000555555897600 in access_with_adjusted_size (addr=20, > value=0x7fffc6c14428, size=4, access_size_min=2, access_size_max=8, > access_fn=0x555555897304 <memory_region_write_accessor>, mr=0x6240000c89e0, > attrs=...) at /home/liqiang02/qemu-upstream/qemu/memory.c:566 > 5 0x000055555589a200 in memory_region_dispatch_write (mr=0x6240000c89e0, > addr=20, data=4587521, size=4, attrs=...) at > /home/liqiang02/qemu-upstream/qemu/memory.c:1442 > 6 0x0000555555835151 in flatview_write_continue (fv=0x6060000e6fc0, > addr=4273930260, attrs=..., buf=0x7fffc8a18028 "\001", len=4, addr1=20, l=4, > mr=0x6240000c89e0) at /home/liqiang02/qemu-upstream/qemu/exec.c:3233 > 7 0x000055555583529b in flatview_write (fv=0x6060000e6fc0, addr=4273930260, > attrs=..., buf=0x7fffc8a18028 "\001", len=4) at > /home/liqiang02/qemu-upstream/qemu/exec.c:3272 > 8 0x00005555558355a1 in address_space_write (as=0x55555683ade0 > <address_space_memory>, addr=4273930260, attrs=..., buf=0x7fffc8a18028 > "\001", len=4) at /home/liqiang02/qemu-upstream/qemu/exec.c:3362 > 9 0x00005555558355f2 in address_space_rw (as=0x55555683ade0 > <address_space_memory>, addr=4273930260, attrs=..., buf=0x7fffc8a18028 > "\001", len=4, is_write=true) at > /home/liqiang02/qemu-upstream/qemu/exec.c:3373 > 10 0x00005555558b66ac in kvm_cpu_exec (cpu=0x631000014800) at > /home/liqiang02/qemu-upstream/qemu/accel/kvm/kvm-all.c:2031 > 11 0x000055555587c3ac in qemu_kvm_cpu_thread_fn (arg=0x631000014800) at > /home/liqiang02/qemu-upstream/qemu/cpus.c:1277 > 12 0x0000555555e54ae6 in qemu_thread_start (args=0x60300002c170) at > util/qemu-thread-posix.c:504 > 13 0x00007fffdadbd494 in start_thread () from > /lib/x86_64-linux-gnu/libpthread.so.0 > 14 0x00007fffdaaffacf in clone () from /lib/x86_64-linux-gnu/libc.so.6 > (gdb) q > > Signed-off-by: Li Qiang <liq...@gmail.com> > --- > hw/block/nvme.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/hw/block/nvme.c b/hw/block/nvme.c > index f206391e8e..0ded74fa9a 100644 > --- a/hw/block/nvme.c > +++ b/hw/block/nvme.c > @@ -1223,6 +1223,11 @@ static void nvme_realize(PCIDevice *pci_dev, Error > **errp) > error_setg(errp, "serial property not set"); > return; > } > + > + if (!n->num_queues) { > + error_setg(errp, "num_queues can't be zero"); > + return; > + } I'd add this as the first check, to avoid the blk_getlength() call. > blkconf_blocksizes(&n->conf); > if (!blkconf_apply_backend_options(&n->conf, > blk_is_read_only(n->conf.blk), > false, errp)) { > With command line comment: Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>