suspend/resume does not work in qemu (qemu-devel)

[Andriy Gapon]

On 19/04/2018 11:54, Andriy Gapon wrote:
> 
> Not sure if this really matters and on what end the problem might be, but
> resuming from S3 in qemu is stuck forever here:

It seems that the same issue _might_ affect real hardware if sc (syscons)
console is used.  What I see is that a system suspends and resumes fine with vt.
If I switch to sc then I see the following message during suspend (never seen
with vt):
	vga0: saving 1024 bytes of video state
And the system fails to resume.
Of course, it is much harder to tell with the real hardware where the resume
fails.  So, I am not sure.

> #3  x86emu_exec_one_byte (emu=0xffffffff81eac618 <x86bios_emu>) at
> /usr/devel/git/cpu-pause/sys/contrib/x86emu/x86emu.c:4655
> #4  0xffffffff8106c398 in x86emu_exec (emu=0xffffffff81eac618 <x86bios_emu>) at
> /usr/devel/git/cpu-pause/sys/contrib/x86emu/x86emu.c:246
> #5  0xffffffff8106b8d4 in x86bios_intr (regs=0xfffffe002e1933f0, intno=16) at
> /usr/devel/git/cpu-pause/sys/compat/x86bios/x86bios.c:634
> #6  0xffffffff80fb7cd2 in vesa_bios_save_restore (code=2, p=0xfffff8000365e004)
> at /usr/devel/git/cpu-pause/sys/dev/fb/vesa.c:551
> #7  vesa_load_state (adp=<optimized out>, p=<optimized out>) at
> /usr/devel/git/cpu-pause/sys/dev/fb/vesa.c:1535
> #8  0xffffffff810632e0 in vga_resume (dev=0xfffff800039eb100) at
> /usr/devel/git/cpu-pause/sys/isa/vga_isa.c:112
> #9  0xffffffff8106311e in isavga_resume (dev=0xfffff800039eb100) at
> /usr/devel/git/cpu-pause/sys/isa/vga_isa.c:243
> #10 0xffffffff80ac2de4 in DEVICE_RESUME (dev=<optimized out>) at ./device_if.h:305
> ...
> 
> Using -vga none works around the problem, of course.
> Maybe it's buggy video BIOS in the emulation.
> 


-- 
Andriy Gapon