Re: [PATCH] target/m68k: implement fmove.l #<data>,FPCR

[John Paul Adrian Glaubitz]

Hi Laurent!

On 5/31/20 1:02 PM, Laurent Vivier wrote:
> The immediate value mode was ignored and instruction execution
> ends to an invalid access mode.
> 
> This was found running 'R' that set FPSR to 0 at startup with
> a 'fmove.l #0,FPSR' in qemu-system-m68k emulation and triggers a
> kernel crash:
> (...)
> Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
> ---
>  target/m68k/translate.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
Thanks for the fix.

I applied the patch, but I'm getting a lock-up now as you previously reported
in the other discussion on the Linux/m68k mailing list:

root@pacman:~# R
[   68.420000] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [R:650]
[   68.420000] Modules linked in: sg evdev mac_hid ip_tables x_tables 
sha1_generic hmac ipv6 nf_defrag_ipv6 autofs4 ext4 crc16 mbcache jbd2 
crc32c_generic sd_mod t10_pi crc_t10dif sr_mod cdrom crct10dif_generic 
crct10dif_common mac_esp macsonic esp_scsi
[   68.420000] Format 00  Vector: 0064  PC: 0002df9c  Status: 2008    Not 
tainted
[   68.420000] ORIG_D0: ffffffff  D0: 00000000  A2: c02e239a  A1: ffa10000
[   68.420000] A0: 3c9adf29  D5: 0000000d  D4: 8002ce30
[   68.420000] D3: 8002b418  D2: 8002b4b4  D1: 00000000

Is this related or a different bug?

I have not seen these lockups on real hardware.

Adrian

-- 
 .''`.  John Paul Adrian Glaubitz
: :' :  Debian Developer - glaubitz@debian.org
`. `'   Freie Universitaet Berlin - glaubitz@physik.fu-berlin.de
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