Re: CVS commit: src/sys/arch/x86/x86

[Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost>]

Hi maxv@n.o,

"intrctl affinity" in NetBSD-current causes panic. Here is the backtrace
====================
panic: kernel diagnostic assertion "mutex_owned(&cpu_lock) || !mp_online" failed: file "/disk4/home/k-nakahara/repos/netbsd-src/sys/arch/x86/x86/idt.c", line 122
fatal breakpoint trap in supervisor mode
trap type 1 code 0 rip 0xffffffff802249e5 cs 0x8 rflags 0x246 cr2 0x72ca08412d98 ilevel 0 rsp 0xffffe4010e898dc0
curlwp 0xffffe4010e88a0c0 pid 0.22 lowest kstack 0xffffe4010e8952c0
Stopped in pid 0.22 (system) at netbsd:breakpoint+0x5:  leave
db{1}> bt
breakpoint() at netbsd:breakpoint+0x5
vpanic() at netbsd:vpanic+0x140
ch_voltag_convert_in() at netbsd:ch_voltag_convert_in
idt_vec_set() at netbsd:idt_vec_set+0x82
intr_activate_xcall() at netbsd:intr_activate_xcall+0x8a
xc_thread() at netbsd:xc_thread+0xd4
====================

ozaki-r@n.o bisects and finds the following commit causes this panic.

On 2017/08/01 3:54, Maxime Villard wrote:
> Module Name:	src
> Committed By:	maxv
> Date:		Mon Jul 31 18:54:40 UTC 2017
> 
> Modified Files:
> 	src/sys/arch/x86/x86: intr.c
> 
> Log Message:
> Use idt_vec_set instead.
> 
> 
> To generate a diff of this commit:
> cvs rdiff -u -r1.101 -r1.102 src/sys/arch/x86/x86/intr.c
> 
> Please note that diffs are not public domain; they are subject to the
> copyright notices on the relevant files.

I think setgate() must be called with kpreempt_disable() and
x86_disable_intr(). However, I don't know why setgate() must be called
with mutex_onwed(&cpu_lock). Could you tell me why mutex_onwed(&cpu_lock)
is required?

BTW, do you have any idea to fix this panic?


Thanks,

-- 
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Internet Initiative Japan Inc.

Device Engineering Section,
IoT Platform Development Department,
Network Division,
Technology Unit

Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost>