On Mon, 13 Feb 2023, Peter Xu wrote:
On Mon, Feb 13, 2023 at 03:47:42PM +0100, BALATON Zoltan wrote:
On Mon, 13 Feb 2023, Peter Xu wrote:
On Mon, Feb 13, 2023 at 12:41:29PM +0100, Thomas Huth wrote:
On 07/02/2023 17.33, BALATON Zoltan wrote:
On Tue, 31 Jan 2023, BALATON Zoltan wrote:
On Thu, 19 Jan 2023, BALATON Zoltan wrote:
Currently -d guest_errors enables logging of different invalid actions
by the guest such as misusing hardware, accessing missing features or
invalid memory areas. The memory access logging can be quite verbose
which obscures the other messages enabled by this debug switch so
separate it by adding a new -d memaccess option to make it possible to
control it independently of other guest error logs.
Signed-off-by: BALATON Zoltan <[email protected]>
Ping? Could somebody review and pick it up please?
Ping?
Patch makes sense to me and looks fine, so:
Reviewed-by: Thomas Huth <[email protected]>
... I think this should go via one of the "Memory API" maintainers branches?
Paolo? Peter? David?
Paolo normally does the pull, I assume that'll still be the case. The
patch looks good to me if Phil's comment will be addressed on merging with
the old mask, which makes sense to me:
Keeping the old mask kind of defies the purpose. I've tried to explain that
in the commit message but now that two of you did not get it maybe that
message needs to be clarified instead?
I think it's clear enough. My fault to not read carefully into the
message, sorry.
However, could you explain why a memory_region_access_valid() failure
shouldn't belong to LOG_GUEST_ERROR?
commit e54eba1986f6c4bac2951e7f90a849cd842e25e4
Author: Peter Maydell <[email protected]>
Date: Thu Oct 18 14:11:35 2012 +0100
qemu-log: Add new log category for guest bugs
Add a new category for device models to log guest behaviour
which is likely to be a guest bug of some kind (accessing
nonexistent registers, reading 32 bit wide registers with
a byte access, etc). Making this its own log category allows
those who care (mostly guest OS authors) to see the complaints
without bothering most users.
Such an illegal memory access is definitely a suitable candidate of guest
misbehave to me.
Problem is that a lot of machines have unimplemented hardware that are
valid on real machine but we don't model them so running guests which
access these generate constant flow of unassigned memory access log which
obscures the actual guest_errors when an modelled device is accessed in
unexpected ways. For an example you can try booting MorphOS on
mac99,via=pmu as described here:
http://zero.eik.bme.hu/~balaton/qemu/amiga/#morphos
(or the pegasos2 command too). We could add dummy registers to silence
these but I think it's better to either implement it correctly or leave it
unimplemented so we don't hide errors by the dummy implementation.
Not to mention Phil always have a good point that you may be violating
others using guest_error already so what they wanted to capture can
misterious going away without noticing, even if it may service your goal.
IOW it's a slight ABI and I think we ned justification to break it.
Probably this should be documented in changelog or do we need depracation
for a debug option meant for developers mostly? I did not think so. Also I
can't think of other way to solve this without changing what guest_erorrs
do unless we change the name of that flag as well. Also not that when this
was originally added it did not contain mem access logs as those were
controlled by a define in memory.c until Philippe changed it and added
them to guest_errors. So in a way I want the previous functionality back.
Regards,
BALATON Zoltan
