Re: [FOUND] kernel 9.0 crash on amd64

[tlaronde%polynum.com@localhost]

Hello,

On Sun, Apr 19, 2020 at 08:17:06PM +0200, tlaronde%polynum.com@localhost wrote:
> Hello,
> 
> On Sun, Apr 19, 2020 at 05:10:37PM +0000, maya%NetBSD.org@localhost wrote:
> > On Sun, Apr 19, 2020 at 05:29:40PM +0200, tlaronde%polynum.com@localhost wrote:
> > > Hello,
> > > 
> > > Mainly in order to be able to test wine, I'm compiling a NetBSD kernel
> > > from netbsd-9-0-RELEASE sources on an amd64 (Intel bicore).
> > > 
> > > My config has very minimal changes from NetBSD 8.* config, the only important
> > > modification being USER_LDT (and I'm not putting option SVS).
> > > 
> > > When it crashes, keyboard is unavailable and the information repeated is:
> > > 
> > > prevented execution of 0x18 (SMEP)
> > > fatal page fault in supervisor mode
> > > trap type 6 code 0x10 rip 0x18 cs 0x8 rflags 0x10246 cr2 0x18 ilevel 0x8
> > > rsp 0xffffcc00ae0cbb40
> > > 
> > > The last bit registered and shown by dmesg (when rebooting with the 8.0
> > > kernel) is about enumerating ahcisata0.
> > > 
> > > Does this ring some bell to somebody?
> > > 
> > > TIA,
> > 
> > SMEP is a hardware method to stop execution user-memory.
> > It tried to execute a function pointer that isn't initialized, most
> > likely.
> > 
> > It would be interesting to see what the backtrace is
> > sysctl -w ddb.onpanic=2 will print the backtrace and reboot, which
> > should make it visible in the back of the dmesg.
> > 
> > Also, if a kernel core dump is done, it should be in /var/crash, gunzip
> > and crash -M netbsd.12 -N netbsd.12.core
> > crash> bt
> > 
> > should print a backtrace.

This the option DIAGNOSTIC that crashes the kernel.

Since the console is frozen and I have no core dump in /var/crash, I set
DDB so that it bt and reboots.

It goes too quick for me to get a full vision of the bt but it
chokes when wandering in usb_event.

If that may have something with it (since all USB attached devices are
keyboard and mouse), PCKBD_CNATTACH_MAY_FAIL is not set.

Best,
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                     http://www.kergis.com/
                       http://www.sbfa.fr/
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