panic: uhci_abort_xfer: not in process context (was Re: uplcom / ucom problems on RELENG_5)

[Ian Dowse]

In message <6.2.1.2.0.20050331074641.04f72eb8 at 64.7.153.2>, Mike Tancsa writes:
>panic: uhci_abort_xfer: not in process context
...
>#6  0xc04d2c1f in usbd_abort_pipe (pipe=0xc19c7e00)
>#7  0xc04c3cf5 in ucomstopread (sc=0x0)
>#8  0xc04c38ba in ucomstop (tp=0xc171c000, flag=1)
>#9  0xc054b393 in ttyflush (tp=0xc171c000, rw=1)
>#10 0xc054974d in ttyinput (c=26, tp=0xc171c000)

In this case I wonder if the transfer needs to be aborted at all,
since it is just restarted immediately afterwards. Mike, maybe you
could try the following patch? Sorry, I haven't tested this, so I
may be missing something obvious.

Ian

Index: dev/usb/ucom.c
===================================================================
RCS file: /dump/FreeBSD-CVS/src/sys/dev/usb/ucom.c,v
retrieving revision 1.51.2.2
diff -u -r1.51.2.2 ucom.c
--- dev/usb/ucom.c	30 Jan 2005 01:00:10 -0000	1.51.2.2
+++ dev/usb/ucom.c	2 Apr 2005 13:10:27 -0000
@@ -929,11 +929,13 @@
 
 	DPRINTF(("ucomstop: %d\n", flag));
 
+#if 0
 	if (flag & FREAD) {
 		DPRINTF(("ucomstop: read\n"));
 		ucomstopread(sc);
 		ucomstartread(sc);
 	}
+#endif
 
 	if (flag & FWRITE) {
 		DPRINTF(("ucomstop: write\n"));