On Mon, 2015-02-02 at 11:37 -0500, Marc-André Lureau wrote: > Hi > > ----- Original Message ----- > > This fixes Spice's smart card support and is related to > > commit 697f3214fd16adcd524456003619f7f44ddd031b. > > > > Reported-by: Swapna Krishnan <skrishna@xxxxxxxxxx> > > > > Recursion is now possible starting with spice_char_device_wakeup calling > > spice_char_device_write_to_device that later (after going through qemu) > > calls spice_char_device_wakeup. Actually, it's the other way: spice_char_device_write_to_device -> (calling) (other functions) -> spice_char_device_wakeup -> spice_char_device_write_to_device > > > > The protecting code is the same to the one in the read path. > > > > This function call loop makes the program to abort with the following > > messages: > > > > usb-ccid: chardev: unexpected message of type 3000000 > > qemu: qemu_mutex_lock: Resource deadlock avoided > > --- > > > > Should I attach the backtrace in the commit message ? > > Yes, please. I'll post it here for now, and later add it to the commit message. (gdb) bt #0 0x00007ffff3fc78c7 in raise () from /lib64/libc.so.6 #1 0x00007ffff3fc952a in abort () from /lib64/libc.so.6 #2 0x0000555555969a95 in error_exit (err=35, msg=0x5555559f8c90 <__func__.5119> "qemu_mutex_lock") at util/qemu-thread-posix.c:48 #3 0x0000555555969b82 in qemu_mutex_lock (mutex=0x5555562c4d60) at util/qemu-thread-posix.c:79 #4 0x0000555555714771 in qemu_chr_fe_write (s=0x5555562c4d60, buf=0x7fffffffd2a0 "", len=12) at qemu-char.c:219 #5 0x000055555586be49 in ccid_card_vscard_send_msg (s=0x5555565c5f80, type=VSC_Error, reader_id=0, payload=0x7fffffffd2e0 "", length=4) at hw/usb/ccid-card-passthru.c:75 #6 0x000055555586bf00 in ccid_card_vscard_send_error (s=0x5555565c5f80, reader_id=0, code=VSC_GENERAL_ERROR) at hw/usb/ccid-card-passthru.c:91 #7 0x000055555586c559 in ccid_card_vscard_handle_message ( card=0x5555565c5f80, scr_msg_header=0x5555565c6008) at hw/usb/ccid-card-passthru.c:254 #8 0x000055555586c72f in ccid_card_vscard_read (opaque=0x5555565c5f80, buf=0x5555565034b0 "", size=12) at hw/usb/ccid-card-passthru.c:289 #9 0x00005555557149db in qemu_chr_be_write (s=0x5555562c4d60, buf=0x5555565034b0 "", len=12) at qemu-char.c:305 #10 0x000055555571cde5 in vmc_write (sin=0x5555562c4e78, buf=0x5555565034b0 "", len=12) at spice-qemu-char.c:41 #11 0x00007ffff4fa86aa in spice_char_device_write_to_device ( dev=0x55555657f210) at char_device.c:462 #12 0x00007ffff4fa9b48 in spice_char_device_wakeup (dev=0x55555657f210) at char_device.c:862 #13 0x00007ffff4ff7658 in spice_server_char_device_wakeup (sin=0x5555562c4e78) at reds.c:2955 #14 0x000055555571d1d2 in spice_chr_write (chr=0x5555562c4d60, buf=0x7fffffffd560 "", len=12) at spice-qemu-char.c:189 #15 0x0000555555714789 in qemu_chr_fe_write (s=0x5555562c4d60, buf=0x7fffffffd560 "", len=12) at qemu-char.c:220 #16 0x000055555586be49 in ccid_card_vscard_send_msg (s=0x5555565c5f80, type=VSC_Error, reader_id=0, payload=0x7fffffffd5a0 "", length=4) at hw/usb/ccid-card-passthru.c:75 #17 0x000055555586bf00 in ccid_card_vscard_send_error (s=0x5555565c5f80, reader_id=0, code=VSC_SUCCESS) at hw/usb/ccid-card-passthru.c:91 #18 0x000055555586c4fc in ccid_card_vscard_handle_message ( card=0x5555565c5f80, scr_msg_header=0x5555565c6008) at hw/usb/ccid-card-passthru.c:242 #19 0x000055555586c72f in ccid_card_vscard_read (opaque=0x5555565c5f80, buf=0x5555565034b0 "", size=12) at hw/usb/ccid-card-passthru.c:289 #20 0x00005555557149db in qemu_chr_be_write (s=0x5555562c4d60, buf=0x5555565034b0 "", len=12) at qemu-char.c:305 #21 0x000055555571cde5 in vmc_write (sin=0x5555562c4e78, buf=0x5555565034b0 "", len=12) at spice-qemu-char.c:41 #22 0x00007ffff4fa86aa in spice_char_device_write_to_device ( dev=0x55555657f210) at char_device.c:462 #23 0x00007ffff4fa8d37 in spice_char_device_write_buffer_add ( dev=0x55555657f210, write_buf=0x555556501f70) at char_device.c:597 #24 0x00007ffff501142d in smartcard_channel_write_to_reader ( write_buf=0x555556501f70) at smartcard.c:669 #25 0x00007ffff501034c in smartcard_char_device_notify_reader_add ( st=0x55555657ef00) at smartcard.c:335 #26 0x00007ffff50112b3 in smartcard_add_reader (scc=0x555556493ee0, name=0x5555565023cc "E-Gate 0 0") at smartcard.c:642 #27 0x00007ffff50118d2 in smartcard_channel_handle_message ( rcc=0x555556493ee0, type=101, size=22, msg=0x5555565023c0 "\003") at smartcard.c:757 #28 0x00007ffff4fbc168 in red_peer_handle_incoming (stream=0x555556588250, handler=0x555556497ff0) at red_channel.c:308 #29 0x00007ffff4fbc231 in red_channel_client_receive (rcc=0x555556493ee0) at red_channel.c:326 #30 0x00007ffff4fc0019 in red_channel_client_event (fd=59, event=1, data=0x555556493ee0) at red_channel.c:1574 #31 0x00005555558b6076 in watch_read (opaque=0x5555565002f0) at ui/spice-core.c:101 #32 0x00005555558e8d48 in qemu_iohandler_poll (pollfds=0x5555562b7630, ret=2) at iohandler.c:143 #33 0x00005555558e89a4 in main_loop_wait (nonblocking=0) at main-loop.c:495 #34 0x00005555557219b0 in main_loop () at vl.c:1794 #35 0x0000555555729257 in main (argc=40, argv=0x7fffffffddc8, envp=0x7fffffffdf10) at vl.c:4350 (gdb) _______________________________________________ Spice-devel mailing list Spice-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/spice-devel