Re: kern/46737: ucom SMP problem

[Martin Husemann <martin%duskware.de@localhost>]

The following reply was made to PR kern/46737; it has been noted by GNATS.

From: Martin Husemann <martin%duskware.de@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/46737: ucom SMP problem
Date: Tue, 24 Jul 2012 17:30:14 +0200

 An example of a backtrace (on amd64) is (manually transcribed):
 
 uvm_fault(0xffffffe8107334a10, 0x0, 1) -> e
 fatal page fault in supervisor mode
 trap type 6 code 0 rip ffffffff80688977 cs 8 rflags 10202 cr2 0 ilevel 6 rsp 
fffffe80011919f0
 curlwp 0xfffffe8136a65680 pid 11 lid 1 lowest kstack 0xfffffe800117e000
 kernel: page fault trap, code=0
 Stopped in pid 11.1 (cu) at   netbsd:getc+0x24:   movzbl 0(%rdx),%r12d
 db{3}> bt
 getc+0x24
 ttread+0x1ac
 ucomread+0x72
 cdev_read+0x5d
 spec_read+0x1cd
 VOP_READ+0x37
 vn_read+x0xa0
 dofilread+0x71
 sys_read+0x62
 syscall+0x94
 
 
 All other cpus were in the idle loop.
 
 Martin